Document M4K8XYVRKkdME5GBOzwyBGbK7

Reprinted From The Journal of The American Medical Association August SI, 1*97, Vol SOI, pp. 577*582 Copyright 2967, by American Medical Association Occupational Acroosteolysis Report of 31 Cases Rex H Wilson, MD, William E. McCormick, MS, Caroll F. Tatum, MD, and John L. Creech, MD In 31 cases of acroosteolysis of the hands of workmen derma. Some have clubbing of the fingers. Only a few associated with vinyl chloride (CHjCHCI) polymerization of the cases have sought medical attention because processes, the osteolysis was specific to the distal pha of symptomatic complaints; the majority have been langes of hands and was frequently associated with Ray found through x-ray examinations of the hands. naud's symptoms. Affected personnel ranged in age from A summary of the physical findings of the ob 26 to 47. The disorder is believed to have resulted from served cases is shown in Table 1, and a detailed de a combination of physical insult, chemical insult, and scription of the two predominantly common symp personal idiosyncrasy. The specific causes are unknown. toms follows: The prevalence was found to be less than 3% among Raynaud's Phenomenon.--This symptom com employees performing similar work. No cases were found plex has occurred in varying degrees, with one or in workmen using or processing the polymer or manu both hands involved. Generally, its effect is observed facturing commercial resins. as marked discomfort on exposure to cold. None of the cases have exhibited vascular changes of the feet. uring mid-1964, several complaints came to our A unilateral sympathectomy performed on one of D attention of soreness and tenderness of the the most seriously affected cases relieved most of fingertips of workmen in a manufacturing plantthe symptoms on that side. The acroosteolysis was polymerizing vinyl chloride (CHsCHCl). Compre not altered by the sympathectomy. hensive examinations of these individuals revealed Roentgenological Changes.--The most unique nothing of significance except a "Raynaud-like phe characteristic of this syndrome is the unusual roent nomenon" of the hands, and in some cases, definite genological findings. These are described as acroos changes of the distal phalanges were apparent on teolysis and are illustrated in Fig 1. It may be present roentgenograms of the hands. Since then we have in all of the fingers and readily observable, or only in observed additional cases of this unusual syndrome. one finger and barely discernible, as illustrated in It is the purpose of this manuscript to summarize Fig 2. X-ray films of the feet, as well as those of the our observations. long bones and of the skull have been made in some of these cases, with no osteolysis found other than Description of Syndrome in the distal phalanges of the hands. To date we have observed 31 cases of hand dis orders among 3,000 personnel involved in vinyl chloride manufacturing and polymerization. All have been men, between the ages of 26 and 47. We have not observed any ethnic or racial tendency for the syndrome. The great majority have been char acterized by two common factors: symptoms likened to those ascribed to Raynaud's phenomenon and acroosteolysis of the distal phalanges. A few have had no symptoms but have the roentgenographic evidence of acroosteolysis. Several of the patients have external skin lesions on the dorsal surfaces of the hands and forearms, with a rope-like appear ance resembling changes sometimes seen in sclero- From the Medical Division. B F. Goodrich Co.,. Akron, Ohio. Reprint requests to 600 S Main St, Akron Ohio 44318 (Dr. Wileon). Acroosteolysis is a rare clinical entity, with only 72 cases of the familial type reported up to 1965, ac cording to Cheney in ids excellent review.1 The diagnosis of acroosteolysis requires expert roent genological technique and knowledge. It has been our observations that early cases of acroosteolysis will be missed by the roentgenologist not familiar with this condition. All of the cases on which we are reporting have been confirmed by at least two ex perienced roentgenologists working independently. We established the following roentgenographic criteria for our diagnoses. These are the result of our having viewed several thousand x-ray films of the hand in our search for the cause of the syn drome. 1. General: Roentgenographically, acroosteolysis, as found in workers who are exposed to vinyl AP00001899 578 ACROOSTEOLYSIS--Wl LSON ET AL chloride and polyvinyl chloride manufacturing processes, is somewhat different from that found in familial osteoporosis with acroosteolysis and in fa milial osteosclerosis with acroosteolysis. In osteopo rosis with acroosteolysis there may be compression fractures in the spine, and basilar impression of the skull, along with destruction of the midpha langes. None of these findings have been seen in these workers. The changes in the distal phalanges are similar in both conditions. Osteosclerosis acroosteolysis observed by Andren et al1 (University Hospital, Malmo, Sweden) in twins showed diffuse sclerosis, with cortical thick ening of the shafts of the long bones and clubbing of the metaphyseal ends. The phalanges of the hands and metacarpals were foreshortened, and the distal phalanges showed acroosteolytic changes. The feet showed the same changes, except that the distal phalanges were not fragmented. There has been no evident destruction in the mid or proximal phalanges of the thumbs or fingers of these individuals and no evidence of a lytic, destruc tive lesion in the feet. We have not observed any loss of calcium salt in the bones of the wrist and remaining bones of the hand and phalanges in any of these individuals, and there has been no evident sclerosis of the wrist and hand bones. 2. Mild stage: The earliest change found in acroosteolysis in these workers has been a loss of the cortex of one or more of the tufts of the distal pha langes, with no destruction of the tuft or shaft of the distal phalanx. The next more advanced stage may be a small, half-moon cut in the cortex of the tuft of one or more Table 1.--Summary of Symptoms and Findings Symptoms Acroocteolysls without Raynaud's symptoms, on* hand Acroestaelysls without Raynaud's symptoms, both hands Acroostsolyiis with Raynaud's symptoms, ons hand Acroosteolysis with Raynaud's symptoms, both hands No. of Cases 4 S 5 17 Total 31 Clubbing of fingsit Skin nodules 8 8 2. Mild stage of acroosteolysis with half-moon de fect of distal phalanx of mid finger. JAMA, Aug 21,1967 Vol 201, No 8 AP00001900 ACROOSTEOLYSIS--WILSON ET AL 579 distal phalanges, or a so-called dice effect along one or more of the tofts. Figure 2 illustrates the small, half-moon cut in the cortex of the distal phalanx of the mid-finger. 3. Advanced stage: A more severe lytic destruc tion may be a complete loss of the tuft and a por tion of the shaft of one or more distal phalanges as illustrated in Fig 1 in which the tuft of the distal phalanx of the right thumb and the tuft of the distal phalanx of the left fifth finger are completely absent. Additionally, there may be in the same hand a portion of the distal rim of the tuft remaining, with loss of the proximal portion of the tuft and a portion of the shaft of the phalanx, which can also be identified in the remaining phalanges in Fig 1. This loss may be of a transverse nature through the shaft and the tuft, or of an oblique type loss of bone structure. 4. Healing stage: In this phase, there is often definite fragmentation of the remaining tuft and of the filled-in area where the previous destruction Was noted through the shaft of the distal phalanx. This may go on to a complete bony union or remain as a fibrous union with fragmentation. In Fig 3 and 4, x-ray films of the same individual well demon strate this. This employee had almost complete reunion of the multiple fragments when first seen in November 1965 and again in November 1966 (Fig 3). In the latter, the completely healed shafts and tufts of the distal phalanges are indicated by no residual fragmentation with fibrous union. There is a definite shortening of the shaft and a widening of i i 3. Above, Aeroosteolysis with marked fragmentation of distal phalanges in November 1965. Below, Same individu al in November 1966. AP00001901 580 ACROOSTEOLYSIS--WILSON ET AL the shaft and tuft, both in the transverse and the anteroposterior diameter. This is most likely due to a combination of constant pressure, and by the nor mal tension of the soft tissues, particularly the ten dons to the distal phalanges. Occupational Aspects of Syndrome Based upon our observations of these 31 cases, it appears as if this syndrome may be of occupational origin and is somehow related to the process of vi nyl chloride polymerization. Its specific cause if not presently known. We are performing extensive re search in an effort to find the cause. Two other pa pers referring to the condition have appeared in the literature. The publication by Suciu et aF contains no specific information, and merely alludes to some hand problem. That of Cordier et aF presents case histories with symptoms similar to many of the cases we describe. This syndrome differs from idiopathic and familial acroosteolysis in that only the hands are involved. Vinyl Chloride Polymerization Process Polyvinyl chloride is a widely used synthetic resin. It has been manufactured commercially for more than 30 years and is used in upholstery fabric, floor and wall tile, wire insulation, phonograph records, and many other commonly used commodities. For many of these uses, the resin (CH-CHClh is mixed with other materials to achieve the desired physical characteristics. The hand syndrome occurs apparent ly only in those people exposed to vinyl chloride or to other chemicals used in the manufacturing process of the resin itself or both. In addition to our exami- Table 2.--Age Distribution of Cases______ Acroestwlytlt Acroosteelytls Without With Aft Group Raynaud'* Symptoms Raynaud's Symptoms 20-29 1 4 30-S9 4 12 4049 4 6 nations of 3,000 personnel performing vinyl chloride manufacturing and polymerization, we have exam ined more than 1,000 individuals who handle the finished resin ot who process it into plastic prod- ducts. No eases of acroosteolysis have been found in these 1,000 persons. Basically, the manufacture of polyvinyl chloride consists of polymerizing vinyl chloride. The reac tion is accomplished in closed containers (polymerizers) with suitable catalysts and emulsifiers. Copolymers, formed by combining vinyl chloride with other monomers, create variations of the homopolymer. These are commercially produced. Following polymerization, the resin is washed, dried, and sold as a finely divided white powder. The polymerization operations are carried out in closed processes and provide little opportunity for employee exposure. Following the completion of the polymerization reaction, periodic cleaning of the walls and agitator of the polymerizer is necessary. The frequency of this cleaning and its method varies with the type of material used in these vessels and with different manufacturers. The most common practice has been to accomplish the cleaning man ually by using hand scraping techniques, with work ers spending several hours each day on this job assignment. Personnel performing this job are com monly referred to as "polycleaners." 4. Left, Healed acroosteolysis with only minor roentgenographlc changes. Right, Same individual one month after crushing injury to midflnger. JAMA, Aug 21,1967# Vol 201, No 8 APOOOOt 902 ACROOSTEOLYSIS--WILSON ET AL 881 Epidemiology We bave attempted to study the relationship of job history to the occurrence o! the disease. Twen ty-seven of our 31 cases have either been on the "polydeaner'' job assignment at the time the syndrome appeared or have, had that assignment at some time in the past. 'This job assignment is the only one showing any positive correlation with the occurrence of the syndrome. Attack Rate.--The syndrome has a low attack rate. Our experience indicates it occurs only in less than 3% of all production employees who at one time have had polycleaning experience. Age Distribution.--The youngest of our cases is 26 years old, and the oldest is 47, with the majority falling in the 30 to 39 age group. The complete dis tribution is shown in Table 2. The appearance of the syndrome among younger employees may be influenced by the fact that the polycleaning job is one of the initial job assign ments into which employees in such plants are hired. Incubation Period.--If this syndrome is related to occupational factors, as we believe, then the time of exposure to these factors should be significant. We have investigated the time spent on polyclean ing and, although accurate job-time assignment in formation is difficult to develop, it appears as if none of these cases has had less than 12 months polycleaning experience. Comment To our knowledge, this is a unique and, with the exception of references 3 and 4, previously unre ported disorder. The spedfic cause is presently unknown, although it appears to be related to the manufacture of vinyl chloride and polyvinyl chlo ride. Not only are the x-ray findings of themselves unique, but when accompanied by the symptoms of Raynaud's phenomenon, the syndrome becomes ex tremely spedfic. As far as we are aware, this has not been an observed response to any toxicant in any of the animal species. We have attempted to arrive at an explanation of its cause, as well as the physio logical mechanism whereby the extreme specificity for the distal phalanges of the hands occurs, but have been unsuccessful. We believe the condition is the result of three factors, all of which must be present for occurrence: (1) a chemical insult, (2) a physical insult, and (3) a personal idiosyncrasy. The chemical insult could occur from one or more of the monomers, catalysts, and intermediate reaction products existing in polymerizers. A low degree of exposure to these could occur from contact with the solid, slightly moist, residue in the polymerizer or to small quantities of vapor, absorbed either percutaneously or by inhalation. Research studies are In progress in an attempt to verify the chemical in sult factor theory. The physical insult is present in all "polydean- ers" to some degree through the prolonged hand scraping operations as well as the occasional use of hammers to remove the residues. In support of the physical insult factor, we have quite recently ob served the effects of a finger injury to an existing case of this syndrome. Figure 4 (.left) . shows an x-ray film of the left hand of the first of these cases ofacroosteolysis (accompanied by Raynaud's symp toms and skin nodules on the dorsal surfaces of the hands). The bone damage is quite limited. Figure 4 (right) shows the same hand with the roentgeno gram taken four months after a crushing injury to the mid finger, with lysis having resulted to the tuft of the distal phalanx. We believe this activity was stimulated by the trauma. Personal idiosyncrasy appears to be an important factor because of the low incidence of occurrence of the disorder. This is especially significant because, although all polydeaners are subjected to essential ly similar chemical and physical insults, the inci dence of this syndrome is very low, and the explana tion for this can only be made on the basis f person al idiosyncrasy. We suspect pertinent factors here are related to the individual's vascular system, the nerves controlling the blood supply to the fingers, and to the spedfic type of collagen in the individ ual's hands. We are in the process of investigating these factors. We have observed no serious disability in any of these cases. A few have been partially disabled be cause of hand soreness, to the extent that some restriction in manual activity was necessary. Im provement in the symptoms, as well as in the roent genological findings, has occurred in many cases without adequate explanation. We wish to emphasize that no cases have been found, after extensive search, in individuals either working with the finished polyvinyl chloride or its copolymers, or in processing the polymer into plastic products. In these processes, more exposure to the polymer occurs than does in the manufacturing of the polymers themselves. We presently believe that personnel assigned to polycleaning should be evaluated, prior to assign ment, for any evidence of collagen disease, oste olysis of the hands, or abnormal response of the hands to cold insult. Any evidence of the existence of any of these factors should contraindicate the as signment of an individual to "polycleaning," and thus remove, or at least minimize, the personal idio syncrasy factor. References 1. Cheney, WJX: Acttvoateolyeia, Amer J Roentgen M:S95-617 (July) 1965. 2. Andren, L., et al: Ostoopetroeil Aerooeteolytiea: Syndrome of Osteopetrosis, Acroosteolysis and Open Sutures of Skull, Acta Chir Samd 124496-507 (Dec) 1962. 3. Suciu, I.; Drejman, I.; and Valsskai, M.: Contributil Studio! Imolnavirilor Produse de Clorura de Vinil, Med intern 16:967978 (Aug) 1963. 4. Cordier, JJL, et el: Acrooeteolyse et Lnidti Cutanees Asaodees Chez Deux Ouvriers. Affectes au Nettoyage D'Antodavea, Cah Med Travail 4: (Jen) 1966. JAMA, Aug 21. 1967 Vo! 201, No 8 AP00001903 y./TT AL sarrttrs. It appears that rites smoked fairly nccunctu.il grams of tohacm differences in CO level* n this study cannot isis of their characterisi iIced different cigarette tKit differences in inhaL. well as factors such as i arc also of some impor- efcronccs uttfu Report of the Adcis^rv Tceorx General of the Puhtf iratioo 2103. Public Health irquences of Smoking: A l*nU. mew: 1967, publication li^. 1908. M, Goldsmith JR* Gttlxm 1 from myocardial infarction 19:510*517,1969. Inmmorid C, Gurfinkcl I.: Jiip to atherosclerosis of the rtr Eng J Med 273;775*77i*. ;ill HC, Richards ML. et al* cigarette smoking habits and is in autopsied males. Circtifo1900. ibson KW, Bross DJ. et ni* lie atherosclerosis and (he i*e hoi. New Eng J Med 279:1-1 l.'J- raiinfr and Atherosclerosis. Co* ikxgnitrd, 1969. arlmn monoxide and coronurv tern Med 71:199-201,1909. Mplan MA. Jacob D: Tobacco: r in anpna pectoris. Ann 7n/crn i. Swanson AJ: Non-nlcotinlzed na pectoris. Ann Jn tern Med Swanson AJ: The effect of Iow an angina pectoris. Ann Intern it, Ilirott MF, Cadlpan JB, e( si .ween alveolar and blood carbon lions during breathholdin*. J 1..V4.1938. okUmllh JR Helwig HU et al: arimn monoxide exposures. Ann H-aiA, 1902. ITastir bags for collection of gas yon Is5f&.fil9, 1967. 'he Analysts of Variance. New Sons. Inc, 1939. /fanIt Correlation Methods, el Publishing Co Inc, 1962. 7. Thompson WA Jr: Rank sum ns in one* and twe>usv cUs>i* JH: 1*7-498. 'A Jr, WHlke TA: On an extreme Riometriha 50^7fV:iA*. tfvnjhnok nf Statistical Tables. bk^m-WesIcy Publishing Co Int*. 61 -SEARCH 4 JAN 2 7 J97; Occupational Acroosteolysis I. An Epidemiological Study wm^ * "* SM/':" Bertram 13. Dinman. MD: Warren A. Cook; Walter M. Whitehouse. MD; and Harold J. Magnuson, MD, Ann Arbor, Mich; and Theodore Ditchech, MD, Phoenix, Ariz Antpidemleloglcsl study wat performed cover* prietary information associated with details log 5,011 employees with 21,510 man.yeart ex* of manufacture, some disinterested group perlence in various phases of vinyl chloride (VC) and polyvinyl chloride (PVC) manufacturing in 32 plants throughout ths United States and Can ada. The total number of definitive cases of acroosteolysis (AOL) was 25; 16 other indi viduals were under suspicion. This condition Is clearly associated with the hand cleaning ot poly* merizers. Workers engaged In cither phases ol VC or PVC manufacturing do not appear to be at was needed to evaluate operating processes, as these might relate to the causation of AOL. Accordingly, the Manufacturing Che mists' Association requested the Institute of Industrial Health (Institute of Environmen tal and Industrial Health as of Jan 1, 1970) to conduct an epidemiological survey of the PVC industry in. the United States and risk of developing AOL. The importance of Ray Canada to meet their responsibility to the naud's phenomenon as a concomitant of AOL workers and the public. is emphasized. Several statistical approaches for The institute was requested to determine rapid medical survey are suggested. Aeroosteolysis appears to be a systemic rather than local disease. Presently, neither the etiological agent nor its portal of entry is known. the extent of the problem among PVC work ers. By establishing a specific job association with AOL, it was hoped to determine where the risk of incurring AOL arose within the PVC process. It was important to determine w whether AOL was associated only with the ITH THE emergence ot a new clinical synthesis stage or if those handling the entity, occupational acroosteolysis (AOL),1 finished polymer also might be affected. it became a manifest responsibility of the polyvinyl chloride (PVC) industry' to define more doarly the character, extent, and pos sible causes of this disorder. Though indi vidual corporations might survey their em The primacy of this consideration stems from the widespread use.of the polymer in the fabrication of a multitude of manufac tured goods that enter general commerce. While the number of workers engaged in the ployees, a statistically.valid construction of chemical synthesis of PVC is relatively the problem could not be developed without collation of the health experience of all PVC small, there are thousands of small manufac turers engaged in the fabrication of products producers. To maintain the privacy of pro- ' derived from this versatile plastic. Submitted for publication Feb 9. 1970; accepted March 24. From the Institute of Environmental and Indus- (rial Health (Dr. Dinman). the Department ot Environmental and Industrial Health, School of iHililie Health (Mr. Cook), the Deputnient of Ra diology, School ot Medicine (Dr. Whltehou>e>, and the School of Public Health (Dr. Macmwom, Uni versity of Michigan. Ann Arbor, and the Doimtm\t of Itadiotogv, Good Samaritan Hospital, I'hoc/iixR. eAprriiznt(Drer.qDuedsrthscctok).Institute of Environmental V*` e*nd Industrial Health, University of Michigan, Anti Arbor.4810*1 (Dr. Dinmrui). Further, it was hoped that the epidemio logical and industrial hygiene2 investigation might define more precisely how variations in manufacturing processes might relate to variations in the prevalence of AOL among PVC producers. Medical and industrial hy giene studies might furnish some clues to the precise etiological agent is) as well as suggest preventive measures that might be applied in the industry. In addition, it was planned that a small, Areh Environ Health--Vot 22, Jan 1971 APOOOOf904 62 OCCUPATIONAL ACtiOOSTEOLYSIS--DINMAN ET At KJW_______ _:------------Soc* SeCf N' 1sri5) RACE w S Other------- ^ Do Not Write in This Box | Corp-_-------^T2) 1COMPANY SERVICE DATE_____ t. --rlsi5) (20-21) (22-23} ARE YOU (RIGHT) (LEFT) HANDED? (24) TO ANSWER THE FOLLOWING QUESTIONS, PUT- A CIRCLE AROUND YOUR ` ANSWER. FOR EXAMPLE: MONDAY IS THE DAY AFTER SUNDAY (YES) (NO) Have you noticed SUDDEN whiteness. blanching, or paleness of the fingers of your RIGHT HAND LEFT HAND (YES) (YES) (NO) (NO) 25 Have you noticed a sudden redness or blueness of the fingers of your RIGHT HAND LEFT HAND (YES) (YES) (NO) (NO) 26 IF YOU HAVE NOTICED ANY OF THE ABOVE, are these changes brought on by cold (YES) (NO) - (DON'T KNOW) 27 HAVE YOUR HANDS OR FINGERS BEEN BOTHERED WITH ANY OF THE FOLLOWING : Tingling or pins-and-needles RIGHT HAND feeling LEFT HAND (YES) (YES) (NO) tNO) 28 Warm feeling in hands or fingers RIGHT HAND (YES) LEFT HAND (YES) 5O2 fOt 29 oft fot Cold feeling in hands or fingers RIGHT HAND (YES) LEFT HAND (YES) 30 Numbness, fingers fall asleep RIGHT HAND LEFT HAND (YES). (YES) (NO) (NO) 31 Stiffness, fullness, or tightness RIGHT HAND of fingers LEFT HAND (YES) (YES) (NO) (NO) 32 Frequent tenderness, soreness. or RIGHT HAND pain at fingertips LEFT HAND (YES) (YES) (NO) (NO) 33 0C( Have you not; your hands, . Thick enii); White, rai ! Whitish pi; Shiny skin Snail, rai; less than 1 (NOT inclut Have you been Pits or sea Ridges or c Have you used at work in the (DAILY) ( Have you ever crushed a fin If yes, was Which f inge Arch Environ Health--Vol 22, Jan I97J wr I AP00001905  *1 r aa Ite In This Box "P^Sj (3-4) :OUND YOUR YES) (NO) YES) (NO) 25 YES) (NO) YES) (NO) YES) (NO) K)N'T KNOW) 27 YES) :yesj (NO) (NO) 28 :yes) :yes) (NO) (NO) 29 :yes) (YES) (NO) (NO) 30 (YES) (NO) (YES) (NO) 31 YES) (NO) (YES) (NO) 32 (YES) (YES) (NO) (NO) 33 A iiVMftfa%M111,1 OCCUPATIONAL ACltOOSTEOLYSlS--DINMAN ETAL rt ^a'rfarr ail 63 Have you not iced any of the following changes of the skin of your hands, wrists, or arms: Thickening of the skin (YES) (NO) 34 If yes, is it on (HANDS) (WRISTS) (ARMS) White, raised patches of skin (YES) (NO) 35 If yes, is it on (HANDS) (WRISTS) (ARMS) Whitish pimples (YES) (NO) 38 If yes, is it on (HANDS) (WRISTS) (ARMS) Shiny skin patches (YES) (NO) 37 If yes, is it on (HANDS) (WRISTS) (ARMS) Small, raised areas, or lumps less than 1/2 inch around (NOT including warts) If yes, is it on (YES) (NO) (HANDS) (WRISTS) (ARMS) 38 Have you been bothered by these fingernail troubles : Pits or scars of the fingernails (YES) (NO) Ridges or cracking of the fingernails (YES) (NO) 39 40 Have you used hand-held power tools or air-driventools at work in the past six years: (DAILY) (ONCE A WEEK) (LESS THAN ONCE A WEEK) (NEVER) 41 Have you ever broken, fractured, or crushed a finger? (YES) (NO) 42 If yes, was it the (RIGHT) or (LEFT) hand? Which finger was injured (Thumb) (Index) (Middle)i (Ring) (Little]| (Thumb) (Index) (Middle) (Ring) (Little) 43 Arch Environ Health--Vol 22, Jan 1971 my; ,l| .1. I.")1' 1 ll.l.pii i IH|J|,II wji u.l i|.W)|i >rrs APOOOOf906 61 OCCVPATIOSAL ACIIOOSTEOLYSIS--DINMAN ET At Oct Selected sample of workers affected with concerning film type, exposure factors, tech follow amputation, AOL be studied in the clinical research unit o( the University ot Michigan Medical Center.* Previously. Kousch and co-workers4 performed an extensive clinical evaluation of a croup of such workers. Subsequent ex aminations here were designed to determine whether any new clinical features had de veloped since those prior studies. nique, nnd identification were sent to each plant. The x-my films, when forwarded to the institute, were coded nnd transmitted without identification to two radiologists for indepen dent interpretation. The findings were recorded on a specifically designed checklist which was then returned for statistical collation. Hand x-ray films that served as controls were drawn front 2,407 men over age 18; this represented enpd phalanges i consistent with n o defect. Defects suc| rosis ot the shafts, of the tufts, and <clubbing were each ble to subjective error. Furthermore, Polyvinyl Chloride Manufacturing: A Brief Review the entire mnle population of the town of Tecumseh. Mich. Work history questionnaires were completed these defects con from other bony ci injury. Even multi; A more definitive description of the proc ess whereby PVC is synthesized, finished, by each individual emptoyee or by the person nel department ot each plant or both. These forms recorded work assignments between Jan arid compounded is reported elsewhere in. I, 1061. through Dec 31, 1966; each worker this issue.* A brief review of the operation is noted the first and Inst month of assignment for appropriate to the premises underlying the each specific assignment during that period. At i involvement could sistent with these c possibilities. Becai problems did exis icant divergencies epidemiological considerations. each piant, a team of investigators converted film irterpretatio Vinyl chloride (VC), together with water, local job designations to standard job titles. found (Table 2). peroxide catalysts, and other additives, are These are listed in the paper on the industrial Because of these placed in a reactor where polymerization is hygiene aspects.* poses of first appr; completed after ten to 16 hours. Unreacted VC is exhausted from the reaction vessel Pilot Run the phalangeal tuft sidered as indicat and the suspension or emulsion of the plas tic transferred to equipment for dewatering and drying. Following ventilation of the re actor, one or two workers enter the vessel to remove the residue from its surfaces, using putty knives or chisels. Sixteen plants, in addition to synthesiz ing, also compound PVC while five plants In order to determine the reliability of survey techniques and recording methodo logical patterns, a pilot run was carried out at one large plant. Following this, minor modification of procedures and forms was accomplished. Epidemiological Design.--Acroosteolysfs appeared to consist of characteristic x-Tay j \ i | '? j roentgenologists in to the presence c existence of margi fragment(s) (defe (defect 3), transvc mentation (defect distal portion of considered as po are engaged only in compounding the resin. film abnormalities and Raynaud's phenome Methods non. Sinco the latter would be expected to occur only infrequently in a population not j j bony defect of At radiologist and if defects could not l Survey Techniques.--Nineteen corporations at risk of developing AOL, it could be used known to be engaged in tho polymerization of as a prime indicator of the existence of AOL. VC were assessed. The workers who served as Thus, wo hoped to establish an initial dis- ; with any of these lowed up subsequi there was a histor. the study populations were employed in 32 - plants in the United Stales and Canada. All employees who worked at the time of tho .survey, or in the past. In any capacity in plants manufacturing VC, PVC. or in rompounding such resin were surveyed.! In multiple-product plants, all workers tuning any prwsiblexpo tinotion between two populations, ie, one having AOL and the other not having it. Comparison of prevalence of defects with the Tecumseh control population of 2,407 men suggested that all defects occurred In the PVC population with s greater frequen- j 1 ! ; i ; involved finger or x-ray film lesions' trauma, these ind from suspicion. Other x-ray filn specific nature an sure to the PVC process were studied. (This cy than in the control population fTnblo 1). { with tho later stag f population underwent medical surveyf^work However, the significance- of this finding was - themselves consul- i 1 history questionnaires, nnd hand x-rny Aiming, clouded by an unavoidable bias which mini The self-completion medical questionnaire mized the value of the Tecumseh population ray film findings phalanges (defect i was designed to probe for signs of Raynaud's as a control group, ie,'identification marks phenomenon or symptoms associated with pe which could not be readily obliterated were { (defect 8) or of : soft-tissue dubbin ripheral vascular insufficiency. In addition, questions were posed to disclose skin or dermal appcmtngo abnormalities, uso of power tools, and hand-injury history. X-rny Alms of both hands were requested from the cooperating plants; specific directions present on these control films. Furthermore, as is apparent from previous discussions of the x-rny film abnormalities. linear rndioluccnt defects could be confused. with old trauma, the absence of a tuft might i j | I ( looked with suspic involving multip' whether they wen 2 to 5). In addition to Arch Enuiron Health--Vef 22, Jan 1971 'iviymr w- i v AP00001907 . P AL xpoture factors, techm wet* **t to each when forwarded to the vl transmitted without diokigist* for indepenfitxCng* wore recorded il checklist which was Mica! collation. Hand aa controls were drawn w 18: this, represented ation ot the town of | j j -| moires were completed oyee or by the pononi plant or both. These ngnments between Jan 31, 1966; each worker nonth of assignment for : during that period. At investigators converted to standard job titles. paper on the industrial j ! i i ( Bun iine the reliability of 1 recording methodoit run was carried out following this, minor dures and forms was i t esign.--Acrooefeolysis if characteristic x-ray I Raynaud's phenomewould be expected to iy in a population not AOL, it could be used the existence of AOL. iablish an initial dis- populalions, ie, one ther not having it. lcnce of defects with 1 population of 2,407 ill defects occurred in rith a greater frequenpopulation (Table 1). nce of this finding was dablo bias which roini Tccuniseh population , identification marks adily obliterated were ol films. ipiiarent from previous ay film abnormalities.- ects could be confused ibsencc of a tuft might i j I | I OCCUPATIONAL ACItOOSTEOLYMS--DINMAN ET AL 65 follow amputation, or short ened phalanges could lie Table l.--Prevtlenct of X-flay Film Oefacls In Control end PVC Populations consistent with a congenital defect. Defects such os scle Control, PVC Population, N - 3.407 N-5.011 rosis of the shafts, widening of tlie tufts, and soft-tissuo Marginal defect Defect No. No. % No. 1 44 1.63 321 % 6.41 rluliiing were cadi suscepti Marginal defect, with residua) ble ' to subjeclive reader fragment z S 0.21 35 0.70 eiror. Furihermore, each of Transverse defeet 3 0.25 40 0.80 these defects could arise from other bony disease or injury. Even multiple finger involvement could he con Transverse defect, with distal fragmentation Total resorption of distal ' portion phalanx Sclerosis, with recsieifteatton 4 s 6 0 21 0.42 3 0.08 9 0.18 I 0.004 15 0.30 sistent with these etiological Shortening 7' 11 0.46 63 1.26 possibilities. Because these problems did exist, signif icant divergencies in x-ray film interpretations were Widening of tuft Widening ol shaft Soft-tissue dubbing Total s 4 0.17 43 0.66 9 t 0.004 7 O.U 10 3 0.06 40 0.80 55 76 3.16 594 11.87 found (Table 2). Because of these complexities, for the pur reported to occur in conjunction with AOL, poses of first appraisal, marginal defects of those x-ray film abnormalities unrelated to the phalangeal tutt (defect 1) were not con AOL were grouped as defect 11. sidered as indicative of AOL unless both Combining the x-ray film findings and roentgenologists independently concurred as Raynaud's; several diagnostic criteria were to the presence of this abnormality. The set up (Table 3). The diagnostic criteria for existence of marginal defects with residual category 0 consisted ot essentially normal fragment(s) (defect 2), transverse defects workers while category 1 included individu (defeet3), transverse defect with distal frag als having x-ray film abnormalities which by mentation (defect 4), and total resorption of history or radiographic evaluation or both distal portion of phalanx (defect 5) were were found to be consistent with old trauma, considered as possibly diagnostic of the disease other than AOL, congenital or famil bony defect of AOL if found by only one ial defects, etc, Tho history of persons in radiologist and if other causes for these diagnostic category 3 disclosed cold-induced defects could not be eliminated. Every man finger blanching unassociated with x-ray with any of these five abberations was fol film abnormalities, clearly meeting our crite lowed up subsequent to the field survey. If ria for AOL. Category 4 consisted of persons there was a history of trauma involving the without Raynaud's phenomenon and sugges involved finger or if the appearance of these tive, though not diagnostic, x-ray films for x-ray film lesions was clearly consistent with AOL. Category 5 included those with classi trauma, these individuals were eliminated cal AOL x-ray film defects (2 to 5 and 1, 6, from suspicion. and 7 without and with concurrence, respec Other x-ray film defects of an even less tively) and Raynaud's phenomenon. Cate specific nature are known to bo associated gory 6 had typical AOL bone abnormalities with the later stages of AOL but are not in (as diagnosed in category 5) but without themselves considered diagnostic. These x- Raynaud-positive replies to the medical ray film findings included sclerosis of the questionnaire. phalanges (defect 7), widening of the tuft Computational and Statistical Analysis. (defect 8) or of the shaft (defect 91. and --Medical and work questionnaires and x- soft-tissue clubbing (defect 10). Finally, we ray film reports were checked for complete looked with suspicion upon any bony defects ness. They wore then coder!, verified, involving multiple fingers regardless of punched, and stored in an electronic com whether they were AOL-spccific (ie, defects puter. Quality control checking of the punch 2 to 5). cards, using a 25% sample, revealed an er- In addition to those defects previously 'ror of 0.1% among these cards. Arch Environ Health--l'of 22. Jan 1971 !PJJ i HII nil. il AP00001908 66 OCCUPATIONAL ACllOOSTEOLYSIS--DINMAN ET AL Tab!* Agrcinttnl and Number of Fingers Showing X-ftay Film DeleeIs In 1402' PVC Workers No. ol Fingers Involved Negative .Marginal dalact Marginal defect. rts residual fragment Transverse dafaet Detect fcw Specific % ho. 1 2 3 4 5 6 7 8 9 10 Total Oefeet Agrea 1 Agree 30 3 0 1 0 0 0 -- -- -- 34 Oisegree 237 30 11 4 3 1 1 287 981 10.6 Total 267 33 31 5 3 1 1 -- -- 321 2 Agree 6 1---- -- -- -- -- -m : 7 Disagree 27 1 -- -- -- -- -- 28 1467 20.0 Told 33 2 35 3 Agree 9 0 --. - 2 0 0 -- -- -- 1 12 Disagree 25 1 -- 0 1 1 -- -m -- 0 28 1462 e 30.0 Total 34 1 -- 2 1 1 -- -- -- 1 40 Transverse dalact. with distal fragmentation 4 Agree 1 -- 1----_---- -- Oisagrec 17 -- 1 Total 18 -- 1 2 18 1.281 20 9.5 Total rasportion 1 distal portion phalanx $ Agrea 21 Oisagraa 5 1 -- -- -- -- -- -- **! -- Total 72 3 6 1.293 33.3 9 Sckrosif, with ^calcification 6 Agree 0 1 0 1 -- 0-------- 2 Disagree 1 2 O -- 1 -- -- mm _ 18 ToUl 9 2 2 1 -- ' 1 -- -- -- -- 20 1.287 13.3 Shortening 7 . Agree 2 1 0 -a 1 -- 1 1 0 Oisagraa 39 6 1 1 -- 1 -- 2 1 1 Total 45 8 2 1 -- 2 -- 3 2 1 12 52 64 1438 18.9 Shortening 7 Agree 6 2 1 0 -- 1 -- 1 l 0 12 Disagree 39 6 1 1 -- 1 --* 2 1 1 52 1.238' 18.9 Tote! 45 8 2 1 -- 2 3 2 1 64 Widening of hilt a Agree 0 3 -- _ _ 0 do 0 -- -- 1 Disegree 35 3 -- -- -- 2 --* 2 -- e- 42 Total 35 . 4 -- -- -- 2 -- 2 -- -- 43 1459 24 Widening of eheft 9 Agrae 0 0-- 0 0 0-------- Disegree 3 1 l 1 1 -- -- -- -- Total 3 1 -- t 1 1 -------- 0 7 1.259 7' 2.3 Soft-tissue dubbing Total* 10 Agrea 3 0_ 0 0 0 0-- 1 -- S. Disegree 26 3 -- 2 2 1 2 -- 1 -- 35 1.295 Total 29 1 -- 2 2 1 2 -- 2 -- 40 Agree 57 9 2 4 O 2 0 1 2' 1 78 Dleegree 423 45 15 8 7 9 3 4 2 1 517 Total 480 54 17 12 7 11 3 5 4 2 595* m The difference between these two figures and those in the defect 11 category, ie. other defects. Is not shown here. Frequently, workers performed several ence on each of the standard jobs could be different duties during a period spent on one computed in terms of months or fractions assignment. Where this existed, an estimate- thereof. was made at each plant of the fraction of The computer was utilized to perform col time spent in each segment of the job lation and statistical manipulations of data. assignment Since the fraction 1/12 was Clinical Evaluation of Positive Cases.-- used for each month a worker spent full Four employees with active disease were time in various jobs during the year, it was admitted to the Clinical Research Unit of convenient to use this fraction of 12ths the University of Michigan Medical Center. where his daily or weekly work was divided Extensive clinical, laboratory, and physio- between two or more jobs. Thus, if a worker logical tests and radiographic, isotopic, nu- spent one halt his time performing one spe tritional, and metabolic balance studies were cific component of his assignment, the value performed. The findings are reported in of 6/12 was assigned ^to our standard job detail.-'1 title for tlint time period on assignment. The remaining 50%. or 6/12, of his Results -time was distributed over one or more applicable job components during the period General Population Statistics.--The study of assignment By this method, job experi population consisted of 5,011 workers, of 1! j ! ! ; j t l j i Arch Environ Health--Vol 22, Jan 1971 OC which 96.4% w. 95.7% were wlii Negro, and 0.2% ,, mean ago was 3: with the median a range being 35 to These workers v ployed by 19 corixi 32 plants in tin States and Cnnnd 32 plants, nil hut engaged in PVC This number of p resented 92% of synthesis industry country. The popi risk represented a 21,510 man years. Population Ann order to construi population groups bute comparisons, plied our diagnost for AOL (ic, x-rn; fects 2 to 5 plus 2 phenomenon). U approach, we four clearly defined cstswere limited to se\ Using these same criteria (Table 31. of 21 plants which gory 0 and 1, or Icviduals in diagnos without bone chan 4 ("AOL qucstioi Raynaud's) or bo there was a risk c those working wit extracted for furtl lation group, com whose employees the finished PVCucts. These three vidual plants in question of AOL' tion of diagnosti four populations r The reason for of x-ray film nb phenomenon to > AOL becomes ap of the three indiv; ry 5 (Ie, x-ray fi wamwav AP00001909 AL 7,302* PVC Work'*/* Negilivi lor Specific % Total Pelect Agree " 34 287 l - 981 10.6 ________ -- 28 1267 20.0 as 12 28 1.262 30.0 40 2 18 1281 9.5 20 . .____________ 3 6 1293 33.3 r________________ .2 18 1287 13.3 20 _______ 12 62 1238 18.9 64 ________________ 12 62 1238 18.9 64____________________ 1 42 1259 43 2.3 0 7 7 6 35 40 ' 78 517 595* 1,259 1295 2.3 other defects, is not shown ctnndard jobs could be if months or fractions iitilhcd to perform colmanipulations of data, n of Positive Cases.-- h active disease were *iral Research Unit of thipnn Medical Center, shorntory, and physioKn*rn|>hic, isotopic, nuJie Utlance studies were Hines arc reported in 9UltS a Statistic!.--The study I of 6,011 workers, of OCCUPATIONAL ACROOSTEOLYSIS--OINMAN ET AL 67 . which 96.4% were men; 95.7% were while, 4.1% Table 3.-- Roentgenographic and Symptomatic Criteria for Diagnostic Categorias 0 to Negro, and 02% other. The mean age was 35.8 years, with the median and modal range being 35 to 39 years. These workers were em ployed by 19 corporations at 32 plums in the United States and" Canada; of the Hand X-Ray: Specific X-Ray Oefeet. Raynaud's Abnormal. Consistent With AOL Diagnostic Phenom* Consistent 'Category non With AOL 1 2 3 4 5 6 7 B 9 10 0 _------ -------- 1 * 3+ t t 4 -- -- i : 5 + +++ ++ + + ++ 6-- + +++ + + + + -4- + 32 plants, all but six were engaged in PVC synthesis. This number of plants rep Indicates only those lesions that may be seen in AOL (delects 8 to 11 though not diagnostic of AOL. t Single finger involved, no concurrence between readers, t No concurrence between reader*. resented 92% of the PVC synthesis industry in this country. The population at Table .--Distribution of Diagnostic'Categories Among Four Subpopulations With PVC Study Group risk represented .a total of Diagnostic Categories 21,510 man years. Population Analysis.--In order to construct several population groups for attri bute comparisons, we ap plied our diagnostic criteria for AOL (ie, x-ray film de fects 2 to 5 plus Raynaud's phenomenon). Using this approach, we found that the clearly defined cases of AOL were limited to seven plants. . Population 0-1 V 4t 5t 6t 7 plants with cases of AOL 9 1.673 1.598 41 9 22 3 3 plants with questionable AOL 17 plants-without AOL 910 1,873 893 14 3 0 0 1,851 17 3 0 0 S plants compounding only Totals 557 5.013 554 2 1 0 0 4,896 74 16 22 3 Raynaud's phenomenon only. t Questionable x-ray, no Raynaud's phenomenon. j X-rays characteristic of AOL. with Raynaud's phenomenon. I X-rays characteristic of AOL. without Raynaud's phenomenon at time of survey. Using these same diagnostic criteria (Table 3), we detected another group but without Raynaud's phenomenon at time of 21 plants which had all employees in cate of survey). We determined by follow-up that gory 0 and 1, or less than a total of two indi of these three workers, two had manifested viduals in diagnostic category 3 i Raynaud's Raynaud's phenomenon during the 1050's without bone change) or diagnostic category prior to any preexposure. The third subject 4 ("AOL questionable" x-ray film without was re-x-rayed subsequent to the survey and Raynaud's) or both. To determine whether demonstrated progressive changes character there was a risk of developing AOL among' istic of AOL; however, he has never noted those working with the finished polymer, we Raynaud's disorder. In view of this finding extracted for further analysis a third popu that 24 of 25 workers with severe AOL-type lation group, constituted by the five plants x-ray film defects had associated Raynau'd's whose employees worked exclusively with phenomenon, we believe it is appropriate to the finished PVC-producing consumer prod link these two abberations in order de ucts. These three groupings left three indi finitively to diagnose AOL. Thus, using as vidual plants in which there remained a our criteria Raynaud's phenomenon or question of AOL's existence. The distribu finger defects qualified as above or both. 25 tion of diagnostic categories among these men were found to have clearly established four populations appears in Table 4. cases of AOL. The reason for requiring the coexistence of x-ray flint abnormality and Raynaud's Intrapopulation phenomenon to establish the diagnosis of Differences AOL becomes apparent upon consideration of the three individuals in diagnostic catego Signs and Symptoms.---We determined ry 5 (ic, x-ray films characteristic of AOL the number of workers in each of the four Arch Environ Health--Vol 22. Jan 1271 -**T* V,|I|II emrr AP00001910 uob. "*v > 68 OCCUPATIONAL ACItOOSTEOLYSIS--DINMAN ET AL Table S.--Inletgroup Prevalence of Raynaud*! Phenomenon Mol Associated IVit/i AOL (Corrected lor Malt Populations Only) seero symptoms, tlio Figure) was difTcrrnt in ixipulntions Diacwitie Category 3 Alone believed to -be free of AOL as contrasted with those % Male Categories No. Population 3*2 Total probably having coses of AOL (see above): This ob plant! with dies o( AOL Plants without cast* of AOL Plants with questionable eases of AOL Plants compounding only servation could be used to 41 3.S0 1.SS2 1.623 screen a group of workers at 19 0.82 2.294 . 2.313 unknown risk of AOL de velopment by simply deter mining how many individu 14 1.70 17 * 831 als reported only a single 3 0.23 438 439 symptom. In order to deter* mine whether more intensive Tsbte 6.--Abnormal Number o1 Cases of Raynaud's Phenomenon Occurring In Various Size PVC-Planl Populations' scrutiny of a group of 25 or more workers at unknown risk of developing AOL is Population Range . - 25-44 45-82 83*120 121-180 181-220 221-280 282*340 341*400 401-460 451-500 Abnormal No. of Raynaud's Phenomenon 3 or meret 4 or more 8 or more or more 7 or more 8 or more 9 or more 10 or more 11 or more 12 or more P-0.01. t Raynaud's, ss detined, is cold, whits fingers brought on by hand or body chilling or both. warranted, one can use a test based upon the normal ap proximation of the binomial, with l-r 1 I \3'3n where n is the number of employees questioned, where n is 24 and p is the fraction of population free of symp plant groups having one, two, three, etc, toms. Should the value obtained exceed 1.65, through 26 positive responses to questions further investigation of the population in concerning signs and symptoms. A graphical question should be considered. representation of the frequency with which The foregoing analyses do not'relate to respondents noted bilateral hand symptoms any individual symptom sought by our med In those plants where AOL was believed to ical questionnaire. These statistical ap occur and in those free of AOL is provided proaches only considered the absence or In the Figure. presence of any one symptom. While thes6 The one-tailed Kolmogorov-Smirnov fK- findings suggest the possibility of asking a S) two-sample test'1 was applied to the two single question to screen a population at distributions. The same analysis was direct- risk of developing AOL. is there any one ' ed to the compounding plant population question that might be used as a more perti AOL-free plant group (see above!. The dis nent screening device? tribution of positive signs and symptoms Focusing once more upon- Raynaud's phe were found similar in both groups. Accord nomenon, we found, by the use of factor ingly, lor tlie "AOL-free" population in the analysis. that this peripheral vascular disor Figure, we have included the employees of der was significantly related to AOL. That the compounding plants. On the basis of is, those questions which npi>ear to be con affirmative responses concerning the pres sistently answered positively as a group con ence of any symptoms, this test Indicated stitute a cluster of symptoms or a factor. In that these two distributions did not stem addition, each symptom is associated with from a common population pool < P < 0.0011. factors by scores called "loadings." which This K-S test indicates that the' frequency weigh the association."!! strength of the fac of Occurrence of the asymptomatic state (ie, tor to the question at hand, ie, the occur- Arth Environ Health--Vol 22, Jan 1971 Oi rence of AOL. Tht clusterings of symi factor analysis, q (questionnaire for naud's phenomenc stitutes one reason lence of this part among any group mont This logically k the relative preva nontenon in our subgroupings. Ho\ phenomenon is m APOOOOf9f 1 \jb. lL ptoms, the Figure) rent in imputations to be free of AOL tasted with those having cases of e obovo). This ob- i could be used to group of workers at i risk of AOL de- at by simply deter- *ow many Individu- rted only a single a. In order to deter- ethor more intensive of a group of 25 or orkers at unknown I developing AOL is d, one can use a test pon the normal api tion of the binomial, v 2`i \ h ' if n n is the number of pcs questioned, where and p is (he traction ilation free of symj> attained exceed 1.65, f the population in :dcrcd. H>s do not relate to 1 sought by our medirse statistical aprod the absence or mplom. While these *ribility of asking a -t*n a population at I* is there any one used as a more perti- upon Raynaud's phov the use of factor alwrnl vascular disorLitcd to AOL. That eh nj>i>car to be con:i\ely as n group con1>tonis or a factor. In in is associated with d "loadings," which i strength of the fachand, ie, the occur- CA4 OCCUPATIONAL ACltOOSTEOLYSiS--UlNilAN ET AL 69 rencc of AOL The most significant of these clusterings of symptoms was found to be, by factor analysis, questions 25, 26, and 27 (questionnaire form 1, ic, indicators of Ray naud's phenomenon. Accordingly, this con stitutes one reason for examining the preva lence of this particular symptom complex among any group at risk of AOL develop ment. This logically leads to an examination of tho relative prevalence of Raynaud's phe nomenon in our various plant-population subgroupings. However, because Raynaud's phenomenon is more frequently associated with women and since that sex represented a relatively small part of the total study population, we first removed tho female re spondents from our data pool. Applying ^ analysis, wo found that the prevalence of Raynaud's phenomenon was significantly different in the plants believed to be free of AOL (P < 0.01) while no difference- was found between the "AOL-free" plants and the compounding locations (Table 5), If indeed the "AOL-freo" plants represent a population at no significant risk of develop ing this disorder, one might infer that Ray naud's phenomenon may occur nmong tho Arch Environ Health--Val 22, Jail 1971 I i APOOOOf9f2 70 OCCUPATIONAL ACIIOOSTEOLYSIS--DINMAN ET AL Tiblt 7.--Intergroup Differences Between Four Groups of PVC Plants Question No. 25 36 ' 2< 29 30 31 32 33 34 35 36 37 35 39 40 7 Plants With Cases of AOL. * 1,673 VS 17 Plants Without Cases Of AOL, O ar 2.873 + + 4- + + + -- + -- +- +. -- -- -- 7 Plants With Cases of A01. n 1.673 vs 5 Plants Compounding, n-557 + -- -- -- -- -- + -- -- + -- -- Significant difference, P < 0.01. x* analysis, f He significant difference, P > 0.01. x* nalysls* * 27 Plants Without Cases f AOL. n 1,373 vs 8 Plants Compounding, -557 -t -- -- -- + -- -- -- -- -- -- -- --. -- 3 Plants * With Cates of? AOL, n -- 910 vs 17 Plants With Cases of AOL. n --1.673 -- -- + -- + + 4-- + -- + -- -- -- + 3 Plants With Cases Of? AOL, n*910 vs 17 Plants Without Cases of AOL. n - 1.373 -- `-- -- -- -- + -- -- -- .-- -- -- -- -- general papulation in eight of 1,000 men. occurrence of AOL appeared to be some We are unaware Of any epidemiological data what more like the AOL-frce group than the confirming this impression. AOL-affected population. Extending our screening approach, could One predict the number of cases of Ray Work History Analysis naud's phenomenon which might indicate the need for further investigation? Since it A detailed review of the 25 clearly estab appears that the general male population lished cases of AOL revealed that 18 persons incidence of this circulatory disorder is less had worked in reactor cleaning at some time than 1% (Table 51, by application of the during the study; additionally, six others, by cumulative probability distribution of the follow-up, were found to have worked at this binomial with P * 0.01, one can determine, task prior to the study. The one man who for various sizes of plant population, the had no history of production-line polydean- minimum number of positive responses in ing was a laboratory technician. However, dicative of a possible AOL problem. Table 6 detailed review of his work history indicated indicates the number of cases of Raynaud's experience with bench-scale reactor oi>era- phenomenon which would only rarely occur tion; this job included hand cleaning of by chance (P < 0.01) in various size popu small reactor vessels. Thus, the association lations. of hand cleaning of reactors and AOL dis All signs and symptoms believed to be ease was striking. Because of job progres associated with AOL were compared as to sion practices, practically all persons suf their intergroup prevalences (Table 7). fering from AOL had worked at other PVC There were considerable differences in the production jobs at one time or another. prevalence of most signs and symptoms be Since the lowest paying jobs, ie, reactor tween the plants with and without AOL cleaning and bagging-packing, arc given to while the compounding plants appeared not newcomers, most production workers were to be dissimilar from the population be given these jobs before progressing upward lieved to be tree of AOL By contrast, the into the skilled jobs. The- fact of this upward group about which doubt existed as to the progression is underlined by work histories Arch Environ Health--Vol 22, Jan 1071 ITWU. T TT OCCUi Table t.--Prtnfence Definitive cate* ~ (ie, diagnostic categoric* 5 end 6) of AOL. 25 * Total workers t risk, reactor eftaning, 1,047 Total man-years, rector etaaning experience. i.< Definitive end possible eas* (diagnostic categories 3, 6, and 6). 41 Total workers at risk, reactor cleaning, ],047 Total man-years, reactor cleaning, 1,082 Total PVC work force, male Men at risk, 4,751 Total man-years in PVC population, 21,510 By analysis of survey : t Based on postsurvey reactor cleaning expenenc 1 Assumes that six work of men with AOL; c ger-packer or reactc the frequency of expi ing. . Reactor cleaning 1 with AOL. The prov tor cleaning was on< risk ftotal populatic all workers having experience. For job 500 men, the prevail was greatest for bag AOL per 86 worker population of 860) fone case per 69 population of 893). months at risk, the AOL was even mo with reactor cloanet lence rate of one c at risk C 12,984 lot. Among those jobs man-months at ri.4 approached this pre AP000019I3 T At. C !* * 1 ' 1 3 Plants Willi ClI IT AOL. n --910 V* 17 Plants Without Cates of AOL, -.1.873 t I speared to be someL-frce group than the m. y Analysis ' the 25 dearly estabrnled that 18 persons .'leaning at some time ionally, six others, by o have worked at this The one man who jction-linc polycleantechnician. However, rk history indicated -Kale reactor opera<1 hand cleaning of fhus, the association arlors and AOL disausc of job progresilly all persons sufvnrkrd at other FVC a* time or another, ntf jolw. ie, reactor ticking, are given to uction workers were progressing upward * fact of this upward ed by work histories OCCUPATIONAL ACIIOOSTEOLYSIS--DINAIAN ET AL 71 Table t.--Prevalence of AOL by Diagnostic Category and Reactor Cleaning Exposure (Job 17f Prevalence Reporting Reactor Cltening Experience. 1961 >1966 Reporting Any Reactor Cleaning Experience, by Follow-up Questionable or no History. Reactor Cleaning Definitive eases (! dietnostic categories S and 6) of AOL, 25 Total workers at risk. MMlor (leaning. 1.047 I*' _ 1 -- ceseper. 1.047 58 worker* t . 24 i. 1 n *** P*r 4.047 41 workers _1 _ _ ease per 1*047 workers Total man-yeirs. reactor cleaning experience. 1.032 18* m 1 use per 1,082 60 worker* 24 1 use per 1 use per 1.082 " S " workers . 1^082 * workers gkeJwtitive *rd.po&ctble cases (diagnostic categories 3, 5. end 6), 41 Tetel workers et risk, * reactor cleaning, 1,047 O3*+10#). 1 case oer 1.047 " 37 " workers - Tot*t man-years. reactor cleaning. 1.082 (18-+10-) 1 use 1.082 " 39" workers . Totel FVC work force, male Men at risk, 4,751 # Total man-year* in PVC population, 21,510 28 I 4,751 170 ease per male employees in PVC study population 1 768" case per man-years In FVC study populition (28+6t) 1 4.751 140 este per male employees in PVC study population 34 . 1 21,510 " 633 " esse per man-years in fvc study population 71 1 m 4,751 679 employees In PVC study population 71 21.510 " 3.073 ' man-years In PVC study population By ana lysis of survey data. f Based on po*t*urvey follow-up: six workers in diagnostic categories 5 and 6 were determined to have had reactor cleaning experience; similar data not available for diagnostic category 3 population. % Assumes that six workers in diagnostic category 3 had had no reactor cleaning experience. of men with AOL; only experience as bag ger-packer or reactor operator approached the frequency of experience of reactor clean ing. Reactor cleaning has a strong association with AOL. The prevalence of AOL of reac tor cleaning was one case per 72 workers at risk (total population at risk, 1,047) among all workers having a history of such job experience. For job categories larger than 500 men, the prevalence rate of AOL by job was greatest for bagger-packers tone case of AOL per 86 workers at risk out of a total population of S60) and reactor operators (one case per 69 at risk out of n total population of $93). On the basis of manmonths at risk, the prevalence of dear-cut AOL was even more strikingly associated wjth reactor cleaners; this job had a preva lence Rite of one case per 721 man-months ut risk 112.9S-1 total man-months at risk). Among those jobs reporting 5.(XX) or more man-months at risk, no other job category approached this prevalence mtc. The question might be asked whether plants with AOL differed from plants free of this disorder in regard to the duration of duty tours in reactor cleaning. Analysis did not indicate that men in the former group of plants worked longer tours on this high-risk job. In addition to the 25 clear-cut cases of AOL, there remained some question whether individuals demonstrating Raynaud's phe nomenon with nondescript or borderline x-ray films might have represented early or minimal cases of this disorder. Review of the x-ray films and medical questionnaires of the 74 men in diagnostic category 3 i ie. Raynaud's phenomenon) revealed 1$ men who might have been manifesting an early phase or minimal degree of AOL. Eight of these men had marginal defects, about whoso presence the radiologists could not agree, and two more had widening of the tuft and shaft, with soft-tissue clubbing tom; of the latter subsequently developed multi ple osteolytic lesions). The other eight had Arch Environ Health--Vol 22, Jan 1971 J.1HI II null I.*. 1,1 wr im. qip i1"-- AP00001914 Mb rtLi--LW.nn. <-f 72 OCCUPATIOSAL ACHOOSTEOLYSiS--DlNMAN ET Ah throe, five, six. or. eight other symptoms of diagnosis occurred with a prevalence of one AOLon history but no bony abnormalities. case ]x>r 721 mon-months exposure. Compar Antons there 16 individuals about whom ing those plants with cases of AOL with there is suspicion of AOL, we found that ten comtxmnding plants by \* analysis, signif of them reported cx|ieriencc in reactor icant symptoms <vsl occurred considerably cleaning. This reported exiterience in reactor more frequently in the plants with cases cleaning was somewhat similar to the work (P < 0.01) or loss than In those compound history found among those men with clcar- ing only. Jn this group of compounders, Ait AOL, ie, 18 men of the 25 cases. It there were no persons showing x-ray film would be of interest to determine the proba- . defects of a questionable nature without bility of finding that among 16 men chosen Raynaud's phenomenon (diagnostic catego at random from the study population, ten or ry 4). In summary, it would appear that more would report such work 'experience. manipulation of the finished PVC resin is Among 5,011 individuals surveyed, 1,047, or probabiy not associated with a risk of con 21%, reported experience in this specific job.. tracting AOL. Considering this entire study population, -r the probability that within a random sample Comment of 16 men we would find by chance ten or more reporting experience in reactor The disease acroosteolysis appears to be. cleaning is only 0.00038 fie. 38 chances in dearly associated with hand cleaning of poly- 100,000). This determination is based uixnt merizers. In these plants using high-pres 'application of the cumulative probability sure water lances or solvents for cleanup of distribution, where . polymerizers, there were possible cases in flC!) ro.21') 10.79)"-* 2 - ftvl. x! (. -x!) ; where ii *= lfi. only one. There appeared to be a correlation between the extent of degassing prior to entry into the reactor.1 It is apparent that time alone will tell At this time, work practices, rather than whether these last eight individuals will de any one specific ingredient or combination velop AOL. Nevertheless, because we know in the. process, appear to determine whether that at least one individual in this suspi this disease will occur. In view of the low cious group subsequently has developed prevalence, the.probability of the occurrence dear-cut AOL, we believe that 25 cases un of AOL is correspondingly low in a small derestimates the total number of AOL cases plant. However, smaller plants without cases in the population study. Therefore, we have at the time of the survey should not consider considered that in addition to the 25 clear- themselves immune to this problem. cut cases, these 16 might also be categorized Indeed, several plants with relatively in the AOL group for statistical purposes, small populations do have this disease providing a total number of 41. On this among their workers. An examination of the . basis, the prevalence of cases in the .general intimate details of their work practices plant population of AOL is calculated in might clarify these ambiguities. While Table 8. plants with cases of AOL provided gloves Experience Among Compounding Work- for their reactor cleaners, we observed in eis.--One of the reasons for performing this consistent usage. Furthermore, while the Study was to determine whether fabricators standard procedures used to "air out" the handling PVC polymer risked development reactor before entry are well designed to of AOL. None of the cases of clcar-cut AOL minimize exposure, these were frequently occurred among this group of 1,257 employ found, upon worker inquiry, to liave been ees despite there being 57,657 man-months experience. Among the 557 men working as compounders, there was only one case of Raynaud's phenomenon. The prevalence of . Raynaud's phenomenon among compound ers was one case per 6.406 man-months "short-cut." That host characteristics may be determi nant of the pathogenesis of AOL is suggest ed by the low prevalence of this condition, ic, idiosyncratic "sensitization" or "suscep tibility" must be' seriously considered. It experience while in reactor cleaners, this will he recalled- that a number of inade- Areh Environ Health--Val 22,.Jan 1971 OC quatoly defined U tinlly polymerized reside in Uic re connection, the s dextranpoiyvinyl ] era should be roc, to see how a hicl 10,000) compound taneously, the po* absorption and k> remain open. In ; pears to be a sy.st( inclined toward t entry rather than absorption. The possibility i this disease is caus, one producing a s picture. In this cot a report of Plesitzi notes the occurrcnc non resulting from ble that the Rayn; stems from residue ated with the PVC walls? Contrariwis. animals produced Viola9 did not app. vasomotor lability. To answer some data are required, cal characterizatioi which remains on 1 tial. Animal exposti ble components are Finally, medical toms of Raynaud's ] ic hand x-ray films present It may trar man-years experienc manufacturers now: workers wiil, as tin ment of some cases. ^i|im wm.i m.wi .i i II" u.wif i i uj,' w.w i.. iwwwwpieMwwiinjiLw a nyn.ii AP00001915 A -AL v prevalence of one t exposure. Compar3i!M of AOL with _^s analysis, signifxurred considerably ' plants with cases in those compoundip of compounders, showing x-ray film ble nature without . (diagnostic categowould appear that lished PVC resin is with -a risk of con- j J ; j j i J j ent olysis appears to be and cleaning of polynts using liigh-prcsIvcnts for cleanup of to possible cases in rd to be a correlation ! degassing prior to imctices, rather than iiont or combination to determine whether . In view of the low lity of the occurrence ingly low' in a small r plants without cases y should not consider this problem, ants with relatively > have this disease In examination of the their work practices ambiguities. While AOL provided gloves w*rs, we observed inrthermore, while the lied to "air out" the arc well designed to h>-se were frequently inquiry, to have been Isti<s may be ilclcmunk of AOL is KUggPSl-nee of this condition, -iti/ntion" or `\suscc|>riuusly considered. It t n mttnbrr of inadc- j j i < OCCUPATIONAL ACIiOOSTEOLYS1S--DINMAN ET AL 73 quately defined low molecular weight, .par tially polymerized nmleriuls are bc-lieved to reside in tlic rcucior scrapings. In this connection, the sensitizing proixTOilies of dextranpolyvinyl pyrrolidine plasma extend ers should be recalled.7 While it is difficult to see how a high molecular weight (MW 10,000; compound could be absorbed pcrcutoncously, the possibility of respiratory tract absorption and systemic distribution must remain open. In addition, because this ap pears to be tt systemic disease, we are more inclined toward the pulmonary portal of entry rather than the transdcniial route of absorption. The possibility might be considered that this disease is caused by several agents, each one producing a specific component of the picture In this connection, there is existent a report of Piesitzer and co-workers5 which notes the occurrence of Raynaud's phenome non resulting from VC exposure. Is it possi ble that the Raynaud's component of AOL stems from residual, unreacted VC associ ated with the PVC remaining on the reactor walls? Contrariwise, the hone changes in animals produced by VC monomer by Viola5 did not appear to be associated with vasomotor lability. To answer some of these questions, more data are required. A more complete chemi cal characterization of the residual PVC which remains on the reactor walls is essen tial. Animal exposure to these various possi ble components are desirable. Finally, medical surveillance for 'symp toms of Raynaud's phenomenon and period ic hand x-ray films appear indicated for the present. It may transpire, as more men and man-years experience accumulate, that those manufacturers now free of AOL among their workers will, as time goes by, see develop ment of some cases. This caution particular ly applies to employees in the PVC synthe sis are.-t. It must be emphasized tliat tho limitations of any rclrosiioctive epidemiolog ical study make impossible any definitive prediction.of future consequences of PVC manufacture. Since such studies can only describe events of the past and up to instant of the survey, the recommendations as to work practices and medical surveillance be come especially pertinent for the safety of those workers. This investigation was su|>t>orted by a grant from the Manufacturing Chemists' Association. A portion ot the su))port (or use ot computational facilities was made available by grant 1-P07-RR 00417-01 from the Department of Health, education, and Welfare. Mary E. Patno, PhD, and Leigh S. Whitlock, PhD, aided in the statistical analyses, and Horace J. Dodge, MD, provided the hand~x-ray films that served ss controls. References 1. Wilson RE, McCormick WE, TAtum CF. et si; Occupational acn>osteol>sia. JAMA 201:577-581, 1907. 2. Cook WA, Gievcr PM, Dinman BD. et al: Occupational aeroosteolysis: If. An industrial hy giene study. Arch Environ Health 22:74-82, 1971. 3. Dodson VN, Dinman 111), Whltchouse WM, et al: Occupational aeroosteolysis: III. A clinical study. Arch Environ Health 22:&i4>t, 1971. 4. Rousch G Jr. rolycloaner's disease: Clinical aspects. Read before the 22nd annual meeting ot the American Academy o Occupational Medicine, Cin cinnati. 1970. 5. Siepel S: Nonparamelric Statistics, New York, McGraw-Hill Book Co Inc, pp 127-180. 6. Harmon HH: Factor analysis, in Mathematical Methods for Digital Computers. New York, John Wiley & Sons Inc, 1959. chap 18. 7. Thompson \VL, Walton RP: Elevation of plas ma histamine levels in the doc foUowjnc adminis tration of muscle reluxants, opiates and niacroraole- cular polymers. J Pharmacol Exp Ther 143:131-180, 1904. 8. Daniahevski SL. Eporov MN: Gig Tr Prof Zohbl 20:9, Ifltfl. 9. Viola PL: Pathology of yinylchloride, in Pro ceedings of the 16th International Congress on Occupational Health, Tokyo, 1969, to be published. Arch Environ llruHh--Vol 22, Jan J97I PW* `i WffW1* iaewnini.i.ei j am I ) ! AP0000!916 74 Occupational Acroosteolysis II. An Industrial Hygiene Study Warren A. Cost-; Paul M. Gievcr, MPH; Bertram D. Dinman, MD, ScD; and Harold J. Magmmon, MD, MPH, Aim Arbor, Mich An industrial hygiene survey was conducted in respect to occupational acroosteolysis (AOL) in 92 plants engaged in production and compound* ing of polyvinyl chloride. This survey was limited to inspection ot facilities, interrogation of tech* nleal personnel, and statistical analyses. All manufacturing processes and chemicals utilized were explored. A major objective was the iden tification el.variables in processes and chemicals that were peculiar to those plants affording known oases of AOL. No such processat or chemicals were found. The survey brought to light a num ber of situations suspected of relationship to the precise cause of AOL, some of which require additional exploration. Most positive ot these was the finding that essentially all of the persons who developed AOL had served as reactor cleaners using manual methods. Polyvinyl chloride (PVC) has been in production and widespread use for more than 80 years. An extensive account of the chemistry, methods of production, materials utilized, properties, and uses of the PVC resins was recently published in a scries of technical articles by Albright.1-' Uses in dude such diverse products as floor tiles, films for food wrappings, sheeting for show, er curtains, phonographic records, and coat ings for cables. As an indication of the magnitude of the PVC industry, the average operating capaci ty in this country for the year 1969 was about 3 billion lb.' Much PVC is produced in other countries. Even with this extensive production involving thousands of operators, the occurrence of occupational acroosteolysis (AOL) among these workers was not recog nized until about 1961.1 Submitted tor publication Feb S, 1970; accepted April 16,1970. From the Institute of Knvironmental and Indus trial Health. University of Michigan. Ann Arbor. Head before the American Industrial Hygiene Conference. Denver. May 15,1969. Iteprint rec;uests to School of Public Henllh. University ot Michigan, Ann Arbor. Mich 4810-t (Dr. Dinman). The clinical and epidemiological aspects of this condition are discussed in separate papers in this issue of the archives.6- Industrial Hygiene Survey Surveys were made of 32 plants by the authors of this paper, most of the plants being visited by a team of one physician nnd one industrial hygienist. Twenty-six of these were polymer production plants. Vinyl chloride mon omer production plants nml plants engaged in compounding and fabricating of fhc polymer ized resin were .n part of the manufacturing complex nt a number of these locations. Five plants conducted compounding end fabricating operations only, and one plant produced only the vinyl chloride monomer. These plants were located throughout the United States and one in Canada. This survey was designed to obtain informa tion on equipment used, procedures followed, materials involved, extent of exposure to these, and names and descriptions of johs in order to compare practices in the plants where coses of AOL occurred with those in plants experienc ing no cases. The extent of exitoxures was estimated on the basis of general observation, a knowledge of fhe physical, chemical, and physiological prop- Arch Environ Health--Vol 23, Jan 1971 erties of the mat technically inform. setting up three 1 and of relative sc\ quantitative cstlm. rials responsible : absorbed either thr through the skin c made for each of tl Produi Vinyl Chlorid processes for pre described by Albi current use. One tion of hydrogen the presence of a In the other proc pyrolyzed in the catalyst for the p | and HC1. In some ! used, with the H( | these processes bt ! Polyvinyl Chi vinyl chloride co i ance with four p i variations among { ' polymer may hnv } . ing from 50,000 conditions under production procc: pension, emulsio and solvent. A tv ed in the flow-sh steps of these ope paper. For more may be made to 1! f*T ,1IJ j .B.II V.IMIWII" III JJL;SUJU111 |I nuini iu.l.mUJSU r*r AP0000I9J7 OCCUPATIONAL ACROOSTEOLYS1S--COOK ET AL 75 giant* affording known wccsscs or chemicals ought to light a numof relationship to the ime of which require >st positive of these tally all of the persons d served' as reactor rthods. j j. } j ! j dcmiologieal aspects liscussed in separate tlrC AKCHJVES.*-" dene Survey or 32 plants by the oat of the plants being np physician nnd one nty-six of these were it*. Vinyl chloride monnnd plnnts engaged in eating of the polymer- of tlvc manufacturing >f these locations. Five winding and fabricating se plant produced only mer. These plants were United States and one j l j j J igned to obtain informa nt. procedures followed, *nt of exposure to these, <iuns of jobs in order to sr plants where cases of nse in plants experien.cwire* whs estimated on crvntion. n knowledge of . and physiological prop- i | I | | j> Fig 1.--Flow diagram for production of PVC from vinyl chloride monomer. erties of the materials, and discussion with technically informed persons at the plants. By setting up three broad categories of duration and of relative severity of the exposure, semiquantitative estimates were made. Since mate rials ies|>on$ihle for causing AOL might be absorbed either through the respiratory tract or through the skin or both, such estimates were' made for each of these avenues of absorption. Production Operations Vinyl Chloride Production.--The two processes for production of vinyl chloride described by Albright' - were found to be in . current use. One of these involves the reac tion of hydrogen chloride with acetylene in the presence of a mercuric chloride catalyst In the other process, 1, 2-dichloroethane is pyrolyzod in the presence of chlorine as a catalyst for the production of vinyl chloride and HC1: In some plants, both methods were used, with the HC1 produced in the latter of these processes being used in the former. Polyvinyl Chloride Production.--Poly vinyl chloride can be produced in accord ance with four processes, each with many variations among different plants. The final polymer may have a molecular weight vary ing from 6f),000 to 150.1XX), depending on conditions under which it is produced. The production processes are designated as susponsion, emulsion, bulk <or nonsolvcntt, and solvent. A typical procedure is present ed in the flow-sheet (Fig lh The essential steps of these operations are outlined in this paper. For more complete details, reference may be made to the pajiors by Albright.11-3 In the widely used suspension process, deion ized water is first introduced into a large auto clave. usually glass-lined, followed by a wide variety of additives. These include suspending agents such as polyvinyl alcohol, methyl cellu lose. and gelatin, emulsifying agenls such as sulfonated oils, surfactants such as sormtan monotnurate, and buffers such asTodlum bicar bonate. Trichloroethylene may be added to pro duce the lower molecular weight polymers. Cat alysts are added to initiate the polymerization. These are nearly all organic peroxides, with lanrnvl neroxide and diisoprop.vlporoxydicarbonate tfPP) being used at the greater number of"pTfinfS The reactor is then closed, evacuated to remove oxygen, and vinyl chlo ride, normally a gas, is piped in as a liquid under pressure from the tank farm or the vinyl chloride plant. In some plants, the catalyst is added to a charge tank from which it is intro duced into the closed reactor following addition of the vinyl chloride. The mixture is agitated with rotating propel ler blades, and steam initially is directed into the reactor jacket to raise the temperature to 50 or 55 C. Since the polymerization reaction is exothermic, cooling water must be run into the jacket after the reaction has begun to avoid excessive heating. After ton_to 16 hours, the polymerization is essentially complete, and the reactor is brought down to atmospheric pres sure. In most plants, it is placed under vacuum for removal of unpolymerized vinyl chloride monomer and transfer to the monomer recov ery area. The suspension of PVC is then dis charged into a blowdnwn tank below the reac tor. This tank is placed under vacuum for transfer of remaining vinyl chloride to the recos'cry area. In some plants, tho blowdown tank is eliminated. The general np|ienrnnce of the cluirging floor of n polymer plant is shown Arch Environ Health--Vat 22, Jan 1971 i HU H SI'S. I H"lf " w.lMAiaW; > 1 AP000019I8 76 OCCUPATIOSAL ACItOOSTEOLYSIS--COOK ET AL in Re 2. The reactors extend for ten feet or so Water-soluble initiators such as ammonium down to the floor below. persulfate and hydrogen peroxide are used as The polymer slurry is pumped to blend catalysts. Since the fine polymer particles can tanks, then to centrifuges for removal oT much not be readily separated from the emulsion by of the water. The dewatered polymer is passed centrifuging or filtering, a spray dryer Is em through a rotary dryer with heated air, the ployed in this process. temperature of the polymer being kept hoiow The bulk process is similar to suspension HO F to avoid degradation. The dried granular polymerization, but is characterized by the pre polymer is pneumatically conveyed into n cy cipitation of the polymer from the liquid phase, clone separator, with finer particles being re as about 10% of the vinyl chloride becomes moved from the air stream by means of a polymerized. filter-type collector. The polymer particles are Solution polymerization is much the same as ' sized by vibrating screens, then bagged for susiienslon polymerization, but no water is in transfer to compounding and fabricating plants troduced. Instead, the polymerization is con or shipped in bulk. In some plants, the polymer ducted in such solvents as cyclohexane, acetone, is stored in bins prior to being shipped. or n-butano. In the emulsion process, the equipment and Copolymer and Terpolytner Production. . process is essentially the same as in the suspen --In addition to the production qf the homo- sion process up to the drying operations. In order to produce the finer polymer particles characteristic of the emulsion process, a wide polymer PVC, many of the plants also produce copolymer and terpolymcrs, includ y- variety of emulsifying agents is used. These ing vinyl chloride. The greater percentage of S may he soaps such as ammonium or sodium the monomer tends to be the vinyl chloride S laurafc, surfactants such ns salts of naphthalene in all of these. The copolymer vinyl chlor / sulfonic acid, or various synthetic detergents. ide-vinyl acetate is in highest production Arch Environ Health--Vol 22, Jan J97I 1 1 I i*i ! f l OT among this group ) minor product in o son to the liutwv Other copolymers :ir cWoride-vinyUiii'iii' i and vinyl chloride, vinyl ether. An ex;u a tcrpolynicr is vm\ rlde-n-butyl nuileiiumaleate. Processes, odditis, catalysts essentially cal to those used homopolymer are vt In the production of polymers and terr with the addition to action mixture of tl tional monomers. Vinyl Chloride Il The unpolyineriz.-l chloride removed ir batch following comp polymerization is con a vinyl chloride rerr. by the suction pm places the reactor stripping tank under pressure. Here the vi ride gas that is re placed under pressur dense It together wi vapor to a liquid. 1 and the vinyl chloral miscible, permitting t aration. In some i inhibitor, usually p added to the vinyl to prevent spontonemerization during it used for its purifier: chloride, with the hi: ing in the still, is tr reuse. Reactor CIcanin. polymer has been d and the pressure hi -reactor is aerated, dropping a flexible i blower to the botn> charge normally 'h: the top of the re." area. The loose n water, after which reactor to remove < ing on the reactor is by manual scrap igiwi";u mu ip> i .nnio.jii m ieni.'iwwiT.runi'e.w!< ii.w.ii... AP0000I919 t h such as ammonium peroxide aro used as olymer particles canram the emulsion by spray dryer is emimilar to suspension cterized by the pre ram the liquid phase, >yl chloride becomes is much the same as . Iiut no water is iniymerization is conryrlohcxnne, acetone, olymer Production, tuction of the homo>f the plants also **n*>lymcrs, includrcater percentage of * Iho vinyl chloride olymer vinyl chlorhighest production OCCUPATIONAL ACROOSTEOLt'SIS--COOK ET AL 77 among this group but is a Table 1.--Absolute Pressure-Time Values minor product in cmntmrison to tlx> hontoinlvinrr. Absolute Preasurc`Tim Values Below 10 Absolute Pressure-rune Values af 10 or Above Other copolymers am vinyl ehloridc-vinylidono chloride and vinyl chloride-lauryl- Plant Cod* No. et No. of Reactor Expected Cleaners AOL Cases Plant Codo No. of No. cf Reactor Espcr.tn 1 Ctesnars AOL C?- * vinyl ether. An example of a lerpolytner is vinyl chloride-jt-butyl *mo Icate-dibutyl maleatc. Processes, additives, and catalysts essentially identi Plants With AOL Cases EE 31 0.B B E f * R Plants With Possible AOL Casts cc 32 0.9 Totals 63 1.7 216 5.8 165 4.5 ie 0.4 39 ` 1.1 436 11.8 cal to those used for the homopolymer are employed in the production of the co polymers and terpolymers with the addition to the re action mixture of the addi tional monomers. Vinyl Chloride Recovery.-- The unpolymerized vinyl chloride removed from the P 0 V W Totals DD Totals 30 22 91 SO * 193 * Plants With No AOL Cases 0.8 o 0.6 H 2.5 - L 1.4 S T z AA 5.3 27 26 28 17 *9 17 8 132 Plants Started in Operation in 196$ or 1966 21 0.6 C 54 J 13 21 0.G 67 0.7 0.7 0.8 0.5 0.2 0.5 0.2 3.6 *1.5 0.4 1.9 . batch following completion of polymerization is conveyed to a vinyl chloride recovery area Table 2.--Classification oif Standard Job Titles by the suction pump that places the reactor and the stripping tank under reduced pressure. Hero the vinyl chlo ride gfll that is removed is placed under pressure to con dense it together with water vapor to a liquid. The water and the vinyl chloride are im miscible, permitting their sep aration. In some plants, an inhibitor, usually phenol,' is added to the vinyl chloride Job Title Code Additive makeup (other 1 than catalyst) Bagging and shipping operator 2 Catalyst makeup man Clericals other offices staff 3 4 Compounding and fabricating 5 Dryer operator 6 General laborer, custodial 7 Laboratory supervisor 8 Laboratory technician 9 Maintenance, electrical 10 Maintenance, mechanical 11 Monomer maintenance operator 12 Monomer operator 13 Job Title Monomer recovery operator Monomer supervisor Plant guard, security officer Reaetor cleaner Reactor cleaner, solvent Reactor operator Slurry blender Supervisor, polymer Tank farm operator Utilities area operator (water treatment, etc) Warehouse operator Transfer operator Other than PVC Coi 15 r 17 if< 20 21 ?.Z 23 L'4 25 ?0 to prevent spontaneous poly merization during its distillation, the method due on the agitator blades may require hnmni, ' used for its purification. The recovered vinyl and chisel for removal and sometimes e-.v chloride, with the higher boiling phenol remain ing in the still, is then pumped to storage for reuse. Reactor Cleaning Operations.--After the polymer has been discharged from the reactor and the pressure brought to atmospheric, tho reactor is aerated. This is accomplished by Four plants use water lets with pressure* . from. 300 to 3,000 ll>/sq in for the clontii.operation. UHc omJeS^USPd water jets unlv one of two production buildings, os the ?>,- tional features interfered with movement o; ?. portable high-pressure water unit nlxiui dropping a flexible duct connected to a portable building. Three other plants have been u-i blower to the bottom of the reactor, with dis solvents for reactor^ cleaning. One of t: charge normally through the open manhole at the top of tlic reactor into the charging-floor area. The loose residue is washed out with water, after which one or two men enter the reactor to remove the skin of polymer remain ing on the reactor surfaces. The usual method is by manual scraping witir putty knives. Resi started to use this method late in 1 !V. I second in 1008, and the third from the hr. . ning of plant operation in 15)86. The react"' filled with the solvent which must lie h- .c. and agitated for a prolonged period, as : PVC Is difficulty soluble. Polyvinyl Cltlorido Compounding.--CVa Arch Environ Hcaith--Vof 22. Jan 1071 AP00001920 78 OCCUPATIONAL ACROOSTKOLYMS--COOK XT AL Table 3.--Magnitude of Dotage Expressed at Single Concept at a weekly, monthly; or Seventy/Ouration Exposure Parameters! other jxriod. A classification of 26 job Magnitude* of Dosage Less Than l hr/Wcek 1*8 hr/Week More Then 8 hr/Week Highl 1 2' s 4 s C Negligible Moderate Moderate Moderate None Negligible None Negligible None * None Negligible None None Negligible Intermediate 7 *s 10 11 12 Appreciable Appreciable Appreciable None Negligible Moderate Moderate None * None Negligible None Negligible Moderate Major 19 14 IS 16 17 18 Appreciable Appreciable Moderate Appreciable Appreciable Appreciable None Moderate Nop* Negligible Moderate Appreciable Expressed in order of increasing dosage received from exposure, which it the summation of the three columns to the right. t Severity of exposure is estimated as none, negligible, moderate* or appreciable (or indicated durations. titles for tin* statistical i>urposcs of this study was pre pared (Table 1J>. These job titles corresponded to com parable operations in all the plants and to a common group of types of exposures to production materials. Ev ery job in each of the plants wns given its fraction of time related to tlie job title as defined for the study. De tails of the manner in which this was done are discussed in the accompanying paper on epidemiological aspects of AOL.* Job Progression.--Often the first job assignment of the new employee .is that of reactor cleaner. Unless there pounding consists of mixing PVC with a multi are many reactors, this work docs not require plicity of plasticizers, antioxidants, pigments, emulsifiers, stabilizers, and other special com pounds in ribbon blenders nnd mills. The mix tures are then passed through roll mills or mixers, such as nre used in the rubber industry, where the temperature may rise sufficiently to vaporize some of the plasticizer and other vola tile constituents. The com|>ounrled polymer is then extruded through rolls or dies to form sheets, films, or pellets. These are used in fabricating operations. the entire time of the employee. Part of his time may be spent in bagging or shipping finished polymer or in the handling of cata lysts and other additives. As job openings arise and with accretion of seniority, this employee may progress to higher skilled jobs such as reactor, monomer recovery or dryer operator, or any combina tion of these at any one time. In plants producing other products in ad Job Classification ,' dition to vinyl chloride polymers, employees may transfer between these product areas - Many variables were introduced in the either as full time for a period of months or plants surveyed and even in different units dividing their time within a given week or of the same plant In regard to nearly every even day. The latter occurs particularly phase of the ojrcrations. Investigation of among maintenance personnel. unit jobs in the plants disclosed a wide Where production of vinyl chloride is part assortment of job titles. In fact, a job title as of the operation, operators may rotate be used by the technical supervisors often dif fered from that for the .same job in the same plant as listed by the personnel de partment Furthermore, a job assignment in one tween jobs in the production of the mono mer and those associated with the produc tion of the polymer. The length of time spent at various jobs is a function of production needs, economic plant might include a different group of unit conditions, plant growth rates, and activity operations than in another plant. Also, the of other product lines. proportion of time devoted to the several unit operations often differed. To compound Occupational Exposures to Materials the difficulties of classification, workers Extent of Exposures.--Information was would frequently rotate through several jobs obtained not only on each of the materials Arch Environ Health--Vol 22, Jan 1571 I used or product exposure to eacl botli duration factors was cstii sure was record week, from one more than eight as" negligible, Since it was not als might be spiralory tract, the extent of ex these avenues of For statistica to combine the into a single do.ly the effect of differing physio somewhat with i grees of duratio ble combinatior were listed in ir classified in thn ignated as slig These combinat 2. Materials Invc material* were u tion of PVC, the acetate, and othi incorporating vii included monomc sants, inorganic c ulation, emulsify ganic solvents t aliphatic nnd a chlorinated, hydi materials does nr in the compound A computer a materials was ur ent time, this ha materials introd plants exhibiting used in plants u consideration vva ttrials and also t< Vinyl Chloric the role of vin; fluence in the mates of the e actor cleaners reviewed. Since analyses, they 1 vinyl chloride principally on w*pi .iev i j'm,i m wr"'" AP00001921 tiUlidrfiiaaaMUtfaiUfai iL ' rrrkty, monthly, or mud. tKiCiGitfon of 26 Job r the statistical pur' this study was preTable 1). These job (responded to comopcralions in all the and to common f types of exposures ction materials. Evin each of the plants ten its fraction of ated to the job title d for the study. De lia manner in which (done arc discussed ecompanying paper emiological aspects at Progression.--Often job assignment of employee is that of leaner. Unless there Drk docs not require nployee. Part of his uggtng or shipping k* handling of cats- nnd with accretion re may progress to * reactor, monomer r. or any combinaimc. her products in adolymers, employees we product areas eriod of months or in a given week or ceurs particularly snncl. *iyl chloride is part rs may rotate bertion of the mono* 1 with the produc- U at various jobs is a needs, economic rates, and activity '** to Materials --Information was ^ of tlir materials j | j j j ; j [ j OCCUPATIONAL ACROOSTEOLYS1S-COOK ET AL 79 used or produced but also on the extent of Table 4.--t/sa of Inhibitors With Vinyl CMorldo exposure to each. Since this is a function of both duration and severity, each of tliesc factors was estimated. The duration of cx{x>sure was recorded as less than one hour a week, from ono to eight hours a week, or Plants with Use of Inhibitors In Virgin Vinyl Chloride In Vinyl Chloride Recovery more than eight hours a week; the severity as negligible, moderate, or appreciable. Since it was not known whether the materi als might *be absorbed through the re AOL eases or possible cases Plants without AOL eases 2 3 2 4 spiratory tract, through the. skin, or both, .the extent of eximsure as related to each of these avenues of absorption was recorded. For statistical purposes, it was desirable to combine these two factors of exposure into a single dose value. Although admitted ly the effect of exposure to materials with differing physiological responses would vary somewhat with different combinations of de grees of duration and severity, the IS possi ble combinations of duration and severity were listed in increasing order of dosage and classified in three groups of dose values des ignated as slight, intermediate, or major. These combinations are presented in Table 2. Materials Involved.--A total of 227 different materials were used or produced in the forma tion of PVC, the copolymer vinyl chloride-vinyl acetate, and other copolymers and terpolymers incorporating vinyl chloride. Those materials included monomers, polymers, catalysts, disper sants, inorganic compounds for coalescence reg ulation, emulsifying agents, surfactants, and or ganic solvents (including hydrocarbons, both tion provided and odor observed. The odor of vinyl chloride could be detected in the immediate vicinity of reactors as they were first opened and also when they were first being vented into the cliarging room area. Air analyses conducted by others have shown vinyl chloride concentrations in the reactor prior to ventilating to be in the prder of 3,000 ppm. The lower limit of detection of vinyl chloride by odor is accept ed as 400 ppm. Except under the foregoing conditions, the odor of vinyl chloride was not observed in the general room air. The reactor cleaner enters the reactor af ter the aeration has reduced the vinyl chlor ide exposure to what is considered satisfac tory limits, normally 15 or 20 minutes. The test is either by sniffing at the manhole opening or by use of a flammable vapor indicator. With the lower explosive limit of vinyl chloride at 4%, it requires 400 ppm for the usual type of flammable vapor indi cator to give a positive reading. Where air analyses have been made in a aliphatic and aromatic, ketones, esters, and chlorinated hydrocarbons). This total of 227 materials does not include the many more used in the compounding and fabricating plants. A computer analysis of exposures to these materials was undertaken, but up to the pres, nt time, this has disclosed no constellation of materials introduced into the batch at the plants exhibiting cases of AOL that was not used in plants without cases. However, special consideration was given to certain suspect ma small number of plants with more sensitive instruments, such as the gas chromatograph, it has been found that the vinyl chloride concentration inside the reactor during scraping operations tends to be below 100 ppm and usually about 50 ppm. With the residue containing some unpolvmerized vi nyl chloride, small amounts of this gas are released as scraping is carried on. Air anal yses have shown vinyl chloride concentra terials and also to errtain details of procedure. tions close to the hand during scraping in Vinyl Chloride Exposures.--Ill evaluating the range of 6CX) to 1.000 ppm. the role of vinyl chloride as a possible in Although this study provided no evidence fluence in the causation of AOL. the esti to suggest that vinyl chloride per sc is the mates of the extent of the exposure of re etiological agent, the measurement of vinyl actor cleaners and reactor operators were chloride concentrations may serve as a use reviewed. Since the authors conducted no air ful index to the adequacy of reactor ventila- analyses, they had to judge the presence ol tion. vinyl chloride in the charging floor area Inhibitors In Vinyl Chloride.--An inhibi principally on the basis of general vcntila- tor, usually phenol, may be added to the Arch Environ Health--Vol 22, Jan J971 X'.' " . .............................. "S'llMa.U AP00001922 'ifk. so OCCUPATIONAL ACIiOOSTEOLYSiS--COOK ET AL Table 5.--Reactor Cleaning Procedures ns a possible factor in the Hand Scrpi(ts Plant After Every Coda Batch Less Than Every Cycle Plants with AOL cases X. cX FX K X. ^ R U (through 1964) , X Every 5-12 cycles (building A) CE X by W*t?r Jet From 1965 From 1962 (building B) Cte**tinz by Solvent causation of AOL. Contact with these inorganic and orpiuiic peroxides occurs as they are kindled prior to their introduction into the reactor and also during re actor cleaning if any unre acted catalyst remains in the residue. Twenty-two. _flL-lhe26 plants used lauroy\ perox_'ide. Eight of these were . plants with AOL cases or Plants with possible AOL cases BB Every -`several" cyclas Plants with no AOL cases AX (to September 1964} CX D From 1962 HX J Every 2V4 cycles l Every 4-8 days NX P Weekly From 1965 through 2964. very 2 weeks/ 1965*1966 v qX sX T X Every 1-3 cycles (emulsion) (suspension) , V Every 10 cycles \/ zX AA t Every 4 or more cycles DO X GG On gtass'lined. Intermittently Jn 1966. entirely 'by December 1966 possible AOL cases, and 14 were plants without AOL cases. The next most com mon organic peroxide was *. the IPP, and it, too, was in from September 1964 use in both the positive and the negative plants, in four of the former and in eight of the latter. No catalyst or group of catalysts was used - in all positive plants and in no negative plants. Constituents of Scrapings. --Other suspect materials are constituents of scrapings removed from the reactors during manual cleaning. These are believed to include Come partially polymerized. resins, along with some un reacted catalysts and addi from start of operations tives, and unpolymerized vinyl chloride. Little specif ic information is currently vinyl chloride to prevent spontaneous poly available concerning these constituents. It hssj j_ merization in storage. An inhibitor may also been reported that lnurovl peroxide is definite- /* be added to the vinyl chloride recovered ly associated with residual 1>VC particles. from the reactor. The phenol is removed by whereas lime ul`IIt."TIT1 ri rn.nns_unTC;iyigo \ treatment with caustic soda prior to its in the polymer.4 transfer to the reactor. The practice over the iurilier investigation of the scrapings years covered by the study is presented in from the reactor may be expected to furnish Table 3. The use of the inhibitor in the information that may lead to a better under virgin vinyl chloride at two of the positive standing of the factors involved in causation plants and three of the negative plants, with of AOL. A difficulty in such investigation is Inhibitor being added in the vinyl chloride that the composition of the scrapings is recovery operation in two positive plants continually changing from the time they are and four negative plants, leads to the con removed from the surfaces of the reactor. It clusion that inhibitors probably arc not a is obvious that comparatively small mole factor in AOL causation. cules of partially polymerized vinyl chloride Catalyst Exposures.--Since the catalysts are increasing in size with passage of time, are all active compounds, they were suspect and active constituents such as residual cat- Arch. Environ Jlenlth--Vol 22, Jan 1971 r i mu MB Table 6.-- Method Manuil scraping (i every rcoetor *yci Manual scraping t, 2-3 cycles Manual scraping i( 4-12 cyelts Watrr-jet cleaning Organic-solvent clt, alyst and vinyl creasing or may Prtx Exposure Since all bu diagnosed as pc as reactor deai had cleaned lab inquiry was ma affect the exposi Reactor Clean of man hours r< depended not on but also on the f: the 26 production ly cleaned after sir of the seven | plants with poasii the 17 plants wit manually scraped The procedur plants appears i. the types of pro. tive plants in Tc Procedures Fo mentation.--Sine atile components the reactor surfo^ batch might he f:i motion was olilai vacuum applied t it and the length under this redu. 'volatile materials the reactor suri roughly proper! innd inversely pro the time. Since t material would t< logarithm of thi* an absolute press: hypothesized Ihm APOOOOf 923 UJJUM able factor In the a of AOL. Contact inorganic and orrroxidcs occurs ns ! handled prior to reduction into the ind also during ro sining If any unretalyst remains in the Twenty-two of the : used lauroyl perox;ht of these were .-ith AOL eases or AOL-eases, and 14. ants without AOL he next most cornante peroxide was . suid it, too, was in >th the positive and itive plants, in four ormcr and in eight ittcr. Ho catalyst or catalysts was used tdtivc plants and in ive plants, ituents of Scrapings. suspect materials tituents of scrapings from the reactors manual cleaning, o boliovrd to include irtially polymerized long willi some unentnlysts and addimd unjwlymerized loride. Little specifnation is currently constituents. It has IK-roxido Is definiteual l`VC particles, remains unreacted of the scrapings o*I>ccled to furnish i to a better undertxilvrd in causation u4i investigation is f the scrapings is m the time they are >* of the reactor. It lively small molerimi vinyl chloride *li passage of time, uch as residual cat- OCCUPATIONAL ACllOOSTEOLYSIS--COOK ET AL 81 Table $.--Reactor Cleaning Procedures Method Ucnucl sereping ifter vtr/ reactor cycle Manual scraping altar 2-3 cycle< Manual acreping alter 4-12 cycles Positive Plants 7 0 2 Negative Plants 9 X 4 tile materials remaining in the residue follow ing application of vacuum would approximate a nondimcnsional value obtained by dividing the , absolute pressure in inches of mercury by the logarithm of the time in minutes during which the vacuum was applied. Thus, the lower the AP-T value, the less is the amount of volatile ' materials remaining in tho residue. Another factor affecting removal of vola Watered cleaning Organic80lv*nt cleaning 2 1 2 tile materials is the temperature range over 2 the period that the reactor is under vacuum. Hie variables in temperature control were so diverse that this factor defied classi alyst and vinyl chloride monomer are de fication and could not be incorj^orsted in the creasing or may no longer be present parameter under consideration. Actually, Procedures Affecting Exposures of Reactor Cleaners variations in degree of vacuum and timing of its application were such that meaningful calculation of an AP-T value could be ac complished only for five of the seven posi Since ail but one of the 25 operators tive plants, one of the two with possible diagnosed as positive for AOL had worked cases, and 14 of the 17 negative plants. as reactor cleaners and the one exception .In the subsequent discussion of these val had cleaned laboratory reactors, additional ues, the three plants that started in opera inquiry was made of procedures that might tion as recently as 1965 and 1966, all with affect the OXTKwnre^ of this groan of workers. no AOL cases, are not included as it is not Ju-aelor Cleaning Procedure__The number known whether sufficient time had elapsed of man hours required to clean the reactors . depended not only on the number, of reactors (jfilb but also on the frequency of cleTtlifligrTn 10 of. v' the 2G production nl.int*. renctor< \ycr`< innii'iaU. `Q'c!eancci attef ever*-ffitchjTMs was true of suEeTtli sfct^n positive pliGits and on* of two plants with possible AOL cases. In only nine of the 17 plants with no AOL cases were reactors manually scraped after every batch. The procedures followed in each of these plants appears in Table 4 and an analysis of the types of procedure by positive and nega tive plants in Table 5. Procedures Following Completion of Poly merization.--Since vinyl chloride and other vol atile components of the residue remaining on the reactor surfaces following discharge of the batch might be factors in AOL causation, infor mation was obtained concerning the degree of vacuum applied to the reactor prior to opening it and the length of lime that the reactor was under this reduced pressure. The amount of volatile materials remaining in the residue on the reactor surfaces wur considered to bo roughly proportional to the nlisolute pressure and inversely proportional to some function of the time. Since the rate of removal of volatile material would tend to decrease with time, the logarithm of this factor was used in calculating n absolute pressure-time (Ar-T) value. It was for cases to have developed by the terminal date of the study period. These plants are listed separately in Table 6. The AP-T values ranged from 0.5 to 21. The AP-T values were 10 or above fan entirely arbitrary division line) for four of the five positive plants and for one of the two plants with possible AOL cases. Four of the negative plants gave AP-T values below 10, and seven gave values of 10 or above. Consideration is directed to the number of reactor cleaners and the corresponding num ber of expected AOL cases in the two groups of positive plants as compared with those in the negative plants. The total number of reactor cleaners at risk in the positive or possibly positive plants with an AP-T value of less than 10 is 63; that in such plants with an AP-T value of 10 or more is 436. The relation of these two totals is to be compared with that of the negative plants in which 193 reactor clean ers at risk arc in the four plants with an AP-T of less than 10 and 132 are in the seven plants with an AP-T ahovc (hat value. The number of expected cases of AOI. for each plant is also listed in 'Fable 6. These values were obtained by dividing the num- hypothesized that the relative amount of vola Iw of reactor cleaners at risk by 3S. This Arch Environ Health--Vol 22. Jan 1971 "TT" APOOOOf924 82 OCCUPATIONAL AC1100STEOLYSIS--COOK ET AL figure derives from the paper on epklrmio- Preventive Measures logical aspects of AOI> which reports the The present knowledge as to AOL is such prevalence of AOL or possible AOL as one that categoric statements as to preventive case per 37 reactor cleaners at risk. measures are not justified. However, on a Of the negative plants with an AP-T val somewhat sj>eculativc basis, some measures ue of 10 or more, none of those in operation arc indicated that nuty bo conducive to AO' earlier than 1965 had enough reactor clean prevention: ers at risk to expect an AOL case, whereas 1. Although some manual removat of resi two of the four plants with an AP-T value due from reactor surfaces may be required under 10 have enough workers to expect whim solvents or high-pressure water jets cases. Cases would be expected from the are used for cleaning, the more extensive total population of reactor cleaners in the employment of these methods would greatly entire .group of the seven negative plants reduce the number of man hours required with AP-T values of 10 or more, but the for conducting this operation by manual total number' would be 3.6, as compared methods. with 5.3 expected cases from the entire * 2. The adequacy of ventilation of reactors group of four negative plants with an AP-T prior to entry should be checked with value of less than 10. This contrasts with flammable vapor indicator equipped with a expected cases in the group of positive scale of greater sensitivity than 1% of the plants with an AP-T value of less than 10 as lower explosive limit of vinyl chloride or 1.7, compared with 11.8 in such plants with with other instruments of such sensitivity. on AP-T value of 10 or more. 3. Further investigation of the constituen-, The proportion of the number of reactor cy of the scrapings from the reactor sur/acea cleaners in the negative plants with an AP-T- should be considered, as such information value of less than 10 to the total number might disclose the factor responsible for the in such plants was 193 to 325. This propor causation of the disease. tion for the positive plants was 63 to 499. A X* test demonstrated that the probability of References tills difference between the negative and the 1. Albright I.F: Vinyl chloride processes* positive plants occurring by chance is less Eng 7-1:123-130. 1967. It. Albright LF: Marufseture of vinyl chloride. than 0.001. Chrm Eng 74:219-220. 1967. In order to make this comparison between 3. Albright 1.F: 1'oK rnerfaation ot vinyl chloride. the positive and negative plants with AP-T Ch/m Eng 74il51-156.1967. /4. Albright I.F: Vinyl chloride polymerization by values below and above 10, it was necessary Vsuspension processes vieltls polwiny] chloride res to oversimplify a multiplicity of varying de tails of operational procedures from the time - ins. Chtm Eng 74:145452. 1907. S. Albright LF: Vinyl chloride polymerization by emulsion, bulk end solution processes. Chtm Eng . the polymerization is completed to the time 74:85-92, 1907. the cleaner enters the reactor. Accordingly, 6. PV'C producers. Chrm Eng Newt 47:18-19, 1969. any interpretation of the findings that re 7. Wilson RH. McCormick WE. Tatum CF. et at: duction of the AP-T value below 10 by Occupational erroosteolvsis: Report ot 31 cases. reducing the absolute pressure or keeping JA AM 201:577-581, liXiT.' 8. Einman HD. Cook WA. Whitehouse \VM, it tire reactor at reduced pressure for a longer el: Occupational nrroosioolycU: L An epidemiologi time or both may results in reduction in development of AOL cases should be ap cal study. Arch Enrimn Health 22:111-7.7. lull. 9, TAkIsor VN. Dinman Hi*. Whitehouse \VM. et el: Occupational nrroosteolysis: lit. A clinical proached with great caution. study. Arch Environ Health 22:83.91. 197i, Arch Environ Health--Vol 22, Jan 1971 o. Ill, Ver. Aht Mir Poor subjects vt Clinically. All had the distal phalangi phenomenon. Ail h reactor-vessel clee the common mod: nomenon anteeede subjects was in ne balance. Plelhysn present in three. E Scintiscans of the labelled with radi' variable uptakes i: with the radiosrap clinical laboratory Occupation consists primaril non and osteolvsi the hands. Suciu naud's phenonien 1963.1 Osteolytic other cases.5-7 Ot tures such as he; stigmata of scicri eters, end nurr.c tests have been cally, patients wit the manufacture more specifically the polymerizatio This papeT Tepi clinical investiga AOL. These foe from those emplo in the msnufactu mers throughout 1 Submitted lor pul: March 24. Vrom the section mental Medicine nn Medlrine (Dr. Dod** runmental end InduN*Hr>t the Dcpartm. i)u*trial Health, Sthf* mtHon), and the 1> Whitehouse), Univcr* Keprint request* t and Industrial Henltl Arbor* Mich 48101 `h AP00001925  AOL is such to preventive fowever, on a ome measures lucivc to AOL nnoval of resior be required ire water jets ore extensive would greatly hours, required n by manual don of reactors chocked with tripped with a un \% of the jyi chloride or h sensitivity. the const]tuenreactor surfaces di information Jonsible for the ! : < J ; j i j I j ! j processes. Chtm at vinyl chloride. . of vinyl chloride. polymerization by vinyl chloride rea- polymeriiion by cesses. Chem Eng V Newt 47:18-19. v. Tatum CF. et et: port ot 31 coses. ftritehouse 1VM, et 1. An epuleintologi22*11-73. 1971. Vtiitetuxwe WM. et V 111. A rlinivnl 0-91. 1971. 83 Occupational Acroosteolysis III. A Clinical Study Vernon N. Dadmn, El/); Bertram />. Dirtman. AID; Walter Af. Whileltouse. AID; Ahmed N. M. Nasr, Ml), PhD; and tlarald J. Magnuxon. MD. MPII. Ann Arbor, Mich four subjocte with acrootleolysis were studied Clinically. All had osteolytic lesions, especially in Methods the distal phalanges el the hands, and Raynaud's phenomenon. All had worked as polyvinyl chloride reactor-vessel cleaners, with nand scraping being the common mode ol operation. Raynaud's phe nomenon anlecedcd osteolytic lesions. One of the subjects was in negative calcium and phosphorus balance. Plethysmographic abnormalities were preeent in three. Esophageal motility was normal. Scintiscans ol the hands using sodium fluoride labelled with radioactive fluorine' (.' F) revealed variable uptakes in the lingers which correlated with the radiographic lesions. A wide variety of clinical laboratory parameters were normal. Occupational acroosteolysis CAOL) Each patient was admitted to the Clinical Research Unit. University of Michigan Hospi tal. for a two-week period where detailed medi cal histories were investigated and physical examinations performed. Details of tho work historic* and environmental exposures were de rived from in-plant epidemiological studies car ried out jointly bv the Institute of Environ mental and Industrial Health of the- University of Michigan and the Manufacturing Chemists' Association. Table 1 lists the lalwratory param eters applied. In addition, calcium and phos phorus balance studies were carried out, using a dietary' history to establish a constant cal cium-phosphorus intake to which each patient consists primarily of Raynaud's phenome non and osteolysis of the distal phalanges in the hands. Suciu et al first described Ray naud's phenomenon in polyvinyl workers in 1963.1 Osteolytic lesions were reported in other cases.*'7 Other associated clinical fea- was accustomed. Dnilv 24-hour urine specimens were collected, and stool specimens were pooled every three days for calcium nnd phosphorus determinations. Appropriate correctional com putations for uneaten foods were made. Cate cholamines and 5-hydroxyindole acetic' acid were determined on 24-hour urine collections. tures such as hepatomegaly, the cutaneous often partitioned by six-hour units and usually stigmata of scleroderma, hypothroic! param eters, and numerous abnormal laboratory tests have been reported.'-7 Epidentiologically, patients with AOL are associated with the manufacture of vinyl chloride polymers, more specifically with the hand cleaning of the polymerization reactors. This paper reports the results of intensive clinical investigation of four patients with AOL. These four patients were selected from those employees of 32 plants engaged in the manufacture of vinyl chloride poly collected on days of provocative cold stresses during plethysmographic determinations. Numerous roentgenographic techniques were introduced, ranging from skeletal survey films to barium swallow radiographs and bone xerog raphy. Scans of the hands and sacral regions, using sodium floride labelled with radioactive fluorine (,SF). were undertaken in two of the patients. Plethysmography of the forearms and hands, using the method of Zucifier et al, was employed." Esophageal motility studies were made, using Salndin et al's technique.9 mers throughout the United States. Results Submitted for publication Feb 9, 1970; Accepted March 24. From the ecclion of Omipation.it nnd Envitontnentnl Medicine and die llcp-irlmcnt ot Internal Medicine (!)r. Ond-nn), nnd the fnaiitute of Envi ronmental nnd Indu-iri.il Health fUrs. tlinmnn and Naar), the I)c|i:irtiiieiit of Knvironmcntnl nnd Induviriaf Health, School of I'uldir Health 11 Jr. Mngnuson), nnd the Department of Hadiidtafy Il)r. Whilchmirol, Univcrsitv of Midiit-an. Ann Aitior. Iteprint request, to Inatittne of Environmental nnd Industrial Health. University of Michigan, Ann Arbor, Mich 48104 tDr. Dittman). History.--Blanching of the hands was the first sign of AOL. In two of the men. the onset was gradual over a few weeks, and in two it was abrupt, as shown in Table 2. Cold was the inciting factor in all cases. The blanching was associated with either tin gling of the hands or tenderness of the fingertips. The polyvinyl work exposure-tofirst-blanching ranged from one to 23 Arch Environ Health--Vol 22, Jan 107/ -X "v.'--i--7.H i n.ivrifp. vi'v1'1"' n1**"'1 j *1 ' ' s'j'-nji AP00001926 iSHuttiMil jrr.**. i. ounces of whiskey .Three of Hip t drank milk, and (case 4) averapn rs each day. 11i( les indicated cult- between 1,000 m, rng/day except f tient (case 2) v, intake was 518 patient's normal Fig 1.--Not* transverse defects in distil phalanges of fingers one to four on left hand and Ungers one to three on right hand. Marginal defect is present in distal portion of distal phalanx of right fifth linger (ease 1). take of phosphon 2,400 mg/day w) , ers took in boh Table 1.--Laboratory fnveaffgaffen of AOL Patltnt* Biochemistry Sodium Calcium Potassium Phosphorus Carbon dioxide Cholesterol Chloride , Glucose (fasting) BiUrubln tiirect/totat Urea nitrogen Creatinine Total sarurn protein Electrophoresis serum Albumin *2 T Magnesium lipids Phospholipids Triglycerides Catecholamines Norepinephrine Epinephrine Serum Enzymes Alkaline phosphatase Threonine aldolase Acid phosphatase Malic dehydrogenase Serum glutamic oxaloacetic Glutamic dehydrogenase transaminase Serum glutamic pyruvre transaminase Leucine aminopeptidajse lactic de hydrogenase isogram Aldolase $ 'Nucleotidase Creatine phosphokinase Serine dehydrotase Isocitrate dehydrogenase Immunological Tests Venereal Disease Research Antinuclear factor - Laboratory Cryoglobulins LE cell tmmunophoresfs Direct Coomb's IgA lstex>rhumatoid factor IgM Cold agglutinins lao and 1,800 mg/da\ unusual food c aversions. Some details of tory ore recorded A- firm history of sion was present u father or the moil of the four patien half also had irom. ily members wit mellitus though sonally evidence! ease. Notably, the all four men had eases. The associated and signs of jolt months. The length of the interval bore no (case 1), 15 (case 4), and 25 (case 2) ment are listed it relationship to the mode of onset oi the pack-years. Half drank coffee (three or nino Intermittent trans severity of the symptoms. cups per day). All were casual tea drinkers. static tinnitus was A summary of the habits and dietary Three drank between three and 18 bottles of by three of the foi history of these patients is detailed in Table beer each month. Ono (case 4) drank 120 This occurred ui 3. Three of the four men were cigarette cans of beer per month but no whiskey from sitting or rc- smokers with smoking histories of nine while the others consumed less than four The one patient r tinnitus (case 3) 1 . Fig 2.--Hands show further resorption of bone, resulting In shortening of terminal phalanges of II fingers except left fifth end right fourth, letter having developed transverse defect. Right fifth finger his' shown additional resorption of distal phalangeal tip. Soft-tissue clubbing is ralalcd to shortened phalanges (case 1). ; nasal stuffiness, a; i I hood bronchial nst 1 Physical Exam! f cal findings were joints, as shown i t skin thickening v more clinicians in i contractures were patient (case 1).'. I i the wrist were lit 2). The distal phn: patient (case 3) w. Laboratory Pat r AP00001927 4 l 4 n left hand and af distal phalanx > _______ threonine aldolase Malic dehydrogenase Glutamic dhydrot*na*a IvtfdM minopeptidase Aldolase Creatine phosphakinate Uocitr.te dehydrogenase cats Antinuclear factor Cryoglobulins tmmunophoresls left IgM IgG >, and 25 (case 2) codec (three or nine c casual tea drinkers, hrcc and 18 bottles of (case 4) drank 120 nth but no whiskey aimed less than lour terminal phalanges of rse defect. Right fifth clubbing is related to OCCUPATIONAL ACnOOSTEOLYSIS--DODSON ET AL 85 ounces of whiskey per month. Table 2.--Clinical Features of Patients With AOL at Onset Three of the men rarely drank milk, and the other (ease 4) averaged two glass es each day. Dietary histor ies indicated calcium intakes between 1,000 mg nnd 1,300 mg/day except for one pa tient (case 2) who^e usual Intake was 518 mg/day. This patient's normal dietary in take of pliosphorus averaged 2,400 mg/day while the oth ers took in between 1,500 and 1,800 mg/day. None had unusual food cravings or aversions. Clinical Features Case 1 Case 2 Case 3 Case 4 Blanching* Onset precipitated by eeld Sudden Gradual Gradual Sudden ++++ Associated symptoms: Fingertip tenderness# +++-- Tingling of the hands* -- -- -- + Joint pain Joint stiffness Subcutaneous nodules Elbows Coccyx -- Lew beck Hands. Hands ' ease Knees Hand Knees + 1 hip. 1 wrist. 1 knee. hands Low bsek Saero-itiac -- Muscle swelling Expesure-to-lirst blsneh interval 1 mo Intermittent tinnitus + 6 mo + 18 mo 23 mo --+ Palpitations with exertion ++-- Some details of family his tory are recorded in Table 4. Table 3.--Habits and Dietary Histories of Patients With AOL A firm history or hyperten sion was present in cither the father or the mother in three of the four patients, and one half also had immediate fam ily members with diabetes roellitus though none per Features Cigarette smoking (pack*yr> Average coffee consumption (eups/tiay) Alcohol per month Beer (12-oz unit) Whiskey <oz) Milk (glasses/day) -Case 1 9 9 3 1 Rarely Case 2 25 3 13 4 Rarely Case 3 0 0 8 0 Rarely Case 4 15 0 120 8 2 sonally evidenced the dis Calcium intake (mg/day) 1.045 518 1.327 1.096 ease. Notably, the fathers of Phosphorus intake (mg/day) 1.519 1.587 2.457 1.797 all four men had heart dis eases. Table 4.--Diseases In family Member el Petlent With AOL The associated symptoms and signs of joint involve ment are listed in Tabic 5. Intermittent transient ortho static tinnitus was mentioned by three of the four patients. This occurred upon rising from silting or recumbency. Member Case 1 Father Diabetes meliitus Mother Brother Emphysema Case 2 Heart disease Hypertension* Obesity ... Case 3 Heart disease. Chronic lung disease Hypertension Case 4 Congestive heart failure. Hyperlipemia. Hypertension Obesity ... ... The one patient not having tinnitus (case 3) had chronic postnasal drip, nasal stuffiness, and a prior history of child hood bronchial asthma. Physical Examination.--The major physi cal findings were restricted to the skin and joints, as shown in Table 5. Synovial and skin thickening were observed by two or more clinicians independently. Dupuytrcn's contractures were present bilaterally in one patient (case 1). The extensor ligaments of the wrist were thickened in another (case 2). The distal phalanges of the hands of one patient (case 3/ were shortened. Laboratory Parameters.--The numerous clinical laboratory parameters depicted in Table 1 were found to be essentially normal. All four men vacillated between negative and positive calcium balances day-to-day during the two-week period. Except for one patient (case 2), all averaged a positive balance ranging from 33 to 246 mg/day. This patient managed a deficit of 27 mg/ day, which was primarily a function of renal excretion. AH had positive phosphorus balances except this patient, whose phosphoturin always accounted for more than his stool losses. Five-hydroxyindole acetic acid determina tions were performed on 24-hour urine spoc- Arth Environ Health--V'oi 33, Jan IST1 AP00001928 85 OCCUPATIONAL ACnOOSTKOLYRlS--nOnSON ET At Table S.--Physical Findings cn Pattsnls With AOL intent: which were sometimes Physicsl Findings Skin Oorts Mhicke ning bands Case 1 + Blanching Without cold With cold -- + Joints Synoriat thickening Incidental PIPt MPJ Knees Dupuytrtn's contracture Finger R 2 and 3 L 3 and 4 a Alls fingers, t Proximal interphslangesl. ! Metacarpophalangeal. . Case 2 Case 3 + + ++ PIPt -- -- -- Thickening Shorten* of wrist ing of txtensors finger tips Case 4 . -- + + - -- jvirlilioned in six-hour incre ment* (Table 6). One pa tient's third-period value of 2.8 occurred during n cold stress while plethysmogra phy was being glum* < case 1). Another patient's third value of 1.6 did not increase under similar cold stress fcase 2). Plcthysmographic studies revealed normal pulse vol umes in all but one patient tease 2). All patients ex cept one (case 3) showed di minished pulse volumes with nvrr * - Kfmv '* M V cold stress typical of the Raynaud's phenomenon observed in other dis eases. Esophageal motor activity was normal in all subjects as shown by barium fluoro scopy and Saladin's et al motility technique. Radiological Findings.--The radiographic findings of the four patients analyzed are - ' summarized in the case reports. fS ' T .< no 3.--Erosive and sclerotic changes in sacro-illee joints bilaterally (case 1). ' Fig 4.--Erosive lesions of os calcis posterior to bony spur (case 1). Report of Cases Case I.--X-ray films made elsewhere prior to the patient's hospitalization at the University of Michigan exhibited normal hands on Oct 20, lfIGG, and. in 19G7, showed marginal bono de fects of the right third and left second, third, and fourth distal phalanges and distal fragmen tation of the distal phalanx of the left first digit. On Aug 8. 1967. transverse "defects were noted on the distal phalanges of the left fingers one to four and right one to three, with resorp tion of the distal portion of the distal phalanx of the right fifth finger. The appearance of the hands on Oct 13. 1967. when the patient was first seen, is shown ill Fig 1. Some reparative changes were noted in comparison with the previous films, with persistent transverse de fects in fingers one to four on the left and one to three on the right, with a marginal defect in the distal portion of the distal phalanx of the right fifth finger. Further check-up examination was obtained on Jan 9. 1969. and Oct 24, 1969, the latter being shown In Fig 2. During (his period of time, there has been further resorption of hone, resulting in shorten ing of the terminal phalanges of all fingers except the left filth, which has remained uninvoiced, and the right fourth, which hits main tained its length but has developed a transverse Arch Environ Health--VqI 22, Jan 797/ rp W i.ii ww [i ihp'9i Fig 5.--L' defect in <tis SSCond end Scintigram s r- 11 .. J .. 1 -T-.. . . I i :-|U Villa' 1 AP00001929 i L ch were sometimes ] in six-hour mere* able 6). One paid-period value of rd during a cold tie plothypmogra- ring done (case 1). atient's third value not increase under id stress (case 2). orographic studies normal pulse volill but otic patient All patients exease 3) showed dipulse volumes with typical of the served in other disctivity .was normal by barium fluorootiiity technique." -The radiographic nte analyzed are ports. ASCS dflwhori prior to a at the University sit hands on Oct 20, marginal bone dei left second, third, and distal fragmennx of the left first Hvetsc defects were as of the left fingers a three, with rcsorpf the distal phalanx appearance of the M-n the iiatient was 1. Some reparative wnp.irison with the lent transverse de. on the left and one a marginal defect in itnl phalanx of the heck-up examination and Oct 24. 1960, xne. there has liecn icMilting in shorten<n- of nil fingers has remained unin*h. which hits main-eln|M-d n transverse ; i j i j ' ' j j -I :'L Fig 5.--Left hand shows marginal defect at tip of distal phalanx of second finger, with transverse defect in distal phalanx of third finger. Right hand shows transverse delects in distal phalanges of second and third fingers and an additional distal marginal defect of second finger (top [case .2]). Scintigram shows uptake of sodium fluoride '"F (bottom). Fig 6.--Sacro-iliae joints show? erosive and sclerotic Changes, more marked on left (case 2). eaeuni'v?^! 4* - ;/ I Ilrtl X-iArch Environ Health--Vol 22, Jan 1971 AP00001930 rf.uitmii AnBiiSure mwiiwiitH^ ` '-,-* - -r\ m gg. , OCCVPATIONAL ACHOOSTKOLYSIS--DODSOS ET At. Table C.--Flrt-hydroxylndole Acetic Acid and Catecholamine Stadias In Patients With AOL Casa 1 Cax 2 Calf 3 Cue 4 Urinary Secretion Fiv**hydrexyin<tote ceticacid 6anv2pre Spm-api* Spm>2a 2sm4an Total(1) Tbtal (2) Total a) Cetecholemine Epinephrine Norepinephrine Urine Croat. Urine Creat Urine Croat* Urine Creat Mg Volume (nine Mg Volume inine Mg Volume inine Mg Volume inine 0.7S 390 0.36 2.0 265 0.69 0.92 460 0.42 2.2 240 0.54 2.80 730 0.62 1.2 300 0.69 0.89 140 0.12 1.6 210 0.48 5.39 1.720 1.52 7.0 1.015 2.30 5.8 2.170 1.47 ... ... ... 4.0 1,720 J.46 ... ... ... 7.6 23.6 6.1 390 1,205 416 430 2.444 0.30 0.97 0.33 0.34 1.94 * ... ... defect. The right fifth finger has shown nddi- tional resorption of the phalangnl tip. Soft* tissue dubbing is noted in the shortened phalanges. Some sclerosis is noted along the margins adjacent to the transverse defects. This patient also showed extensive erosive and scle rotic changes in the sacro-iiiac joints, as seen in Fig S. An erosive lesion was also found in the plantar surface of the os calvis.'as depicted in Fig 4. CISC 2.--This putient had an extensive skele tal survey on Fob 8, 1968, with positive findings limited to the hands and pelvis. As shcavn in Fig 5, the left hand revealed a marginal defect at the tip of the distal phalanx of the second finger while the third finger showed a transverse defect in the distal pha lanx. At the same time,' the right hand present. ed transverse lytic defects in the distal phalanges of the second and third fingers and an additional distal marginal defect of the second finger. Figure 5 compares a typical sodium fluo ride >SF scintiscan of the bands and the corre sponding roentgenograms. A slight increase in sodium fluoride *F uptake is seen in the distal phalanges of the left third and right second and third fingers while the uptake is diminished over the distal phalanges of the left fifth and right fourth and fifth fingers. Generally, up takes over the remaining bones of the hands are uniform. The sacro-ilinc joints also displayed extensive erosive and sclerotic change, more marked on the left, as shown in Fig 6. Case 3.--Extensive skeletal survey on this patient on Mart and widening ol fingers (Fig ?). soft tissues. Thethe end stagi-s <>( iae joints shone: more ntnrkcd on Review of pn where indicated changes were ptt the hands had n< October I9G5. Case 4.--Rev; made of this pa mality of the h. 1967, or Jan 23. : the sacro-iiiac jo: rotic changes, an defect of the dis and the right fm of distal phalun.t transverse defect thumbs bilateral!; Skeletal survey ration of the tip right ulna, mar changes of the t some progression transverse defer phalanges of the Fig 10.--Hands phalanges of left fr one and four, wittleft second finger - Areh Environ flrnlth--Vnf 22. Jnn 1971 i,,s.u rap n,i,i,gennriww r 1 AP00001931 If* With AOL Case 4 Urine CrestHe Volume (nine 1.329008 00..3907 416 2<44340 0.33 01..3944 ... eee # in the distal phaird fingers and an feet of (he second pical sodium fiuonds and the corre. alight increase in a seen in the distal id right second and take is diminished F the left fifth and fis. Generally, upmnes of the hands displayed extensive % more marked on tal survey on this arsvltsnt clubbing of rf.HU itim'ria OCCUPATIONAL ACROOSTF.OLYSlfi--DODSON ET AL 89 patient on March 18. 1088, showed shortening and widening of the distal phalanges of nil fingers (Fig 7), with resultant dubbing of tlie soft tissues. These rhnnges were interpreted nsr the end stages of healing of AOL. The sucro-illac joints showed erosive and sclerotic: changes, more marked on the right (Fig 81. Review of previous x-ray films made else where indicated that some sacro-iliac joint changes were present on April 8, 1959, and that the hands had not changed in appearance since October 19G5. Case 4.--Review of previous x-ray -films made of this patient indicated that no abnor mality of the hands was present on Feb 20, 1967, or Jan 23. 1908. On July 15, 19GS, films of the sacro-iliac joints exhibited erosive and scle rotic changes, and the hands revealed marginal defect of the distal phalanges of the left third and the right fourth fingers, slight irregularity ef distal phalanx of the right fifth finger, and transverse defects of the distal plialanges of the thumbs bilaterally. Skeletal survey on Oct 20. 1968. noted sepa ration of the tip of the styloid process of the right ulna, mnrkod rcsorptive and sclerotic changes of the sacro-iliac joints (Fig. 9). and some progression of the hand involvement, with transverse defects now involving the distal phalanges of the left digits one to three and 1 J Fig 8.--Sacro-iliac joints snow erosive anu sclerotic changes, more marked on right (case 3). ->ser' gi . i .vi'j. ' 'V-iT: L .Fig 10.--Hands show transverse defects In distal phalanges of left fingers one to three and tight fingers 4 ne and four, with an additional marginal defect of Fig $aero-ili*c joints show erosive and sclerotic Arch Environ Health--Vol 22. Jan 1071 AP0000I932 so OCCUPATIONAL ACROOSTEOLYSIE--DODSON ET AL right digits one and. four and nn additional At first glance, it appeared that there was marginal dcfcrt of the left second digit (Fig a rich history of heart disease or hyperten 10). Imgularity of the lower pole of the right sion or both in the parents of these men. patella was also noted. Comparison of them with healthy male Comments chemical workers not involved in polyvinyl chloride manufacture and matched in age Raynaud's phenomenon was the first suggests a significant correlation by the x manifestation noted by these subjects and in test, using Ya te's correction. Whether such the majority of the cases reported. Harris an observation suggests a hereditary frailty and Adams1 reported one case in which to explain the susceptibility of those individ distal digit shortening occurred first, while uals developing AOL is speculative. The Wilson et al* noted this in five of his 31 number, of observations is too small to sup cases. This suggests that the vascular lesion port seriously such a contention at this time. tends to antocede the bone changes in most The extent and character of other muscu individuals. None of these patients exhibited lar skeletal findings such as tendon and Raynaud's phenomenon of the feet, which synovia] thickening confirm the findings of confirms Wilson et al's experience. All of others. these individuals had been ``reactor clean We are able to offer no suitable explana ers" fe, they spent some hours each week tion for the frequent episodes of intermittent , cleaning the polyvinyl chloride polymeriza orthostatic tinnitus described by three of tion kettles shortly prior to or at the time of these men. the onset of their disease. No consistent Suciu et al described liver enlargement, relationship was found between the occur- various vague asthenic symptoms, and mani-. 1 renee of severity of either Raynaud's phe festations of hypothyroidism. Such findings nomenon or the osteolytic lesions and those were not present in these men or had they habit patterns which have been shown to been in the past. influence vascular reponses, eg, cigarette The radiological findings in occupational smoking and the ingestion of alcohol, coffee, AOL have been reviewed recently on the or tea. Likewise, neither the bone lesions basis of the epidemiological investigation of nor Raynaud's phenomenon seemed to cor the polyvinyl chloride industry. Workers in relate with the daily consumption of milk or other countries .have described lytic lesions dietary calcium. Dallas and Nordin,u have in the distal phalanges of the hands, styloid shown that while dietary deficiencies or cal processes of the ulna and radius, and the cium may or may not potentiate osteoporo sacro-iliac joints.1-9-* sis of various types, an adequate calcium These four patients demonstrate the en intake of 15 mg/kg is protective. Only one tire spectrum of radiographic hand changes patient (case 2) had less than this amount in occupational AOL from the earliest mar (5.8 mg/kg). Since such dietary histories ginal erosion of the distal phalanx through have been shown to be quite reliable.'1 their the extensive transverse defect, with ulti habitual calcium intakes do not appear to be mate healing resulting in a short and wide a consistent causative factor in their cases. phalanx. The fact that all four showed sac Likewise, the calcium-phosphorus balance ro-iliac involvement suggests that the inci studies on these men reveal no clear-cut dence of involvement at this site is probably abnormality or pattern. This result might be higher than previously suspected. anticipated since these men have been away The additional smaller abnormalities from reactor cleaning for several months, found in the ulnar styloid, os calcis, and and the mass of involved bone is slight lower pole of the patella suggest that these compared to the entire skeleton. However, it areas might well be evaluated in other cases should be pointed out that a two-week bal as they appear in order to get a more accur ance period is a short observation period ate estimate of their incidence. though they wore placed on calcium and The sodium fluoride *F scintiscan data phosphorus intakes comparable to their usu suggests that the more advanced osteolytic al eating habits to obviate disruption of changes with transverse defects at this time their "steady state." were picking up more fluorine and probably Arch Environ Health--Vol 22, Jan 1971 isimw calcium, indiem That the digits up less than the type of uptake ! tion. If the latt interesting that pear to be mint in the same inti The etiological and the pathot obscure. Medical Pre tween the begin the onset of A( ie, one to 23 in quemy with w cleaners has no the occurrence should serve as ther inquiry. This is not to cal practice does nation of reacto of workers in groups should t use of hand rc questionnaires, take has been di cal segment in emphasize that quires the coopi group should be significance of relation to AOL. Upon the disi among workers should be remov. of the hand, b obtained. A me. similar to those survey reported cured. A medical of Raynaud's pi view of the unpr APOOOOf933 *r . J--'-i.-.-f-Jg- -- - --r.- iit.-vV i `Ini I Hi'-'--'tx"*1-2'ii3 4 5 6 7 8 9 10 d that there was jixc or hypcrtentii of these men. h healthy male Ived in pol>-vinyl matched in age lation by the *! m. Whether such hereditary frailty r of those individspeculative. The too small to sup* ition at this time, r of other muscui as tendon and n the findings of suitable explanales of intermittent ibed by three of iver enlargement, iptoms, and manism. Such findings men or had they s in occupational l recently on the al investigation of .uslry. Workers in ribed lytic lesions the hands, styloid d radius, and the monstrate the en[hic hand changes i the earliest mar1 phalanx through defect, with ultl- a short and wide 1 four showed saersts that the ineihis site is probably speclcd. ler abnormalities id, os calcis, and suggest that these nted in other cases gpt a more accurenee. "F scintiscan data dvnnrixl osteolytic tefects at this time" urine and probably j , j ' j 5 j ! : OCCUPATIONA L ACUOOSTEOLYSIS--DODSON ET AL 91 ealcium, indicating active rcmincralizntion. would be wise, to exclude any individual That the digits with marginal defects picked with Raynaud's phenomenon from reactor up less than the normal bones implies some denning. Since seniority practices usually type of uptake block or active demineraliza remove workers from reactor deaning with tion. If the latter is true, it is all the more the passage of time, such excluded workers interesting that different bone lesions ap probabfy would not return to this particular pear to be mineralizing and demineralizing job. Ill view of tho low prevalence of this in the same individual, even the same hand. disease, we believe that permanent restric The etiological agent or agents responsible tion of these few workers from this job does and thu pathogenicnl mechanisms remain not pose any undue administrative burden. obscure. Until more is known of the natural history ' Medical Prevention.--The Interval be of this disease, prudence would dictate the tween the beginning of reactor cleaning and course as here recommended. the onset of AOL appears highly variable, ie, one to 23 months. Accordingly, the frequency with which one examines reactor This investigation was supported bv Public Health i Service grant 2MU1 RR-42 and a grant from me iVijnuiaciuidtifChemists' Association. cleaners has no rational basis. By contrast, the occurrence of Raynaud's phenomenon References " should serve as a sufficient warning for fur ther inquiry. This is not to suggest that prudent medi cal practice does not require periodic exami nation of reactor cleaners and other groups of workers in whom AOL occurs. These groups should be surveyed periodically by use of hand roentgenograms and medical questionnaires. The form the latter might take has been discussed in the epidemiologi cal segment in this series. But we would emphasize that prevention of AOL also re quires the cooporation of supervision. This group should be alerted as to the possible significance of Raynaud's phenomenon in relation to AOL. Upon the discovery of any case of AOL among workers at risk, such individuals should be removed from the job. X-ray films of the hand, back, and knees should be obtained. A medical history questionnaire, similar to those used in the epidemiological survey reported here, should also be pro cured. A medical evaluation for other causes of Raynaud's phenomenon is in order. In view of the unpredictable course of AOL, it 1. Sueiu l, Drojmsn I, -Valeskai: Investigation of the diseases caused by vinyl chloride, jlfed Intern 15:967-978.1963. 2. Cordier JM, Ftevcz C, LeFcvre M*T, et al: Acroosleoiysi* and akin lesions among workers en gaged in cleaning reactors. Cali Med Travail 4:14- 10, 1906. 3. Chatclam A, Motilon F: A syndrome of arroos- teolysis of occupational origin: Heretofore not iden tified in France. J Radiol Klectr 46:277-260, 15*07. 4. Wilson RE, McCovmielc \VJ$, Tatum CF. et al: Occupational acroosteolysis. JAMA 201:577-561, 1907. 5. Harris DK, Adams WGF: Acroosteolysis oc curring in man engaged in tlse polymerization Of vinyl chloride. Brit Med J 3:712-714.1907. 6. Benoit JI': Acroosteolysis of occupational ori gin. thesis. Lyon, 19(56. 7. Hess EV. Schneider H. Roush G: Clinical studies in occupational acroosteolysis: A new dis ease. Read bofore the 40lh meeting of the Central Society for ClinicAl Research, Chicago, 1967. 8. Zweiflcr AT, Cushing 0. Conway FT: The relationship between pulse volume and blood flow in the finger. Ancialngy 16:591-596.19*37. 9. Salndin TA, French Alt, Znrafoniti* CJ. et al: Ksophugenl motor abnormalities in scleroderma and related diseases. Amtr J Die Dit 2:522-535,3966. 10. Dallas I. Norriin BEC: The relation between calcium intake and roentgenologic osteoporosis. Amer J Clin Sutr 11:263-2(59. 1962. 11. Becker BC, Indik Hr. Beeuwkes AM: Dietary Intake Methodnlociex: A Review, technical igport. Ann Arbor. Mich, University of Michigan, l9iK), up 55-57. Arch Environ Health--Vol 32, Jan 1271 APOOOOf934 LIBERTY MUTUAL INSURANCE COMPANY 1718 PEACHTREE ROAD, N.W. ATLANTA, GEORGIA 30302 1 1V r / *-- *i Itec^bw m 1973 Hr* A* HeHillan. Plant Kanager .Air Products Chemicals, Inc* S715 P. O. Box 467 Pensacola, Florida 32502 ws ,o' /y"> \` /n % t*i'A) Bear Hr. HcMlltnt On December 4, 1973* I visited your Pensacola Flant to review l'th 0/ nadical aspects of ycur plant safety and health prograa. /ifter * touring tht> plant, I sut with you, Hr* Odom, ilra* Pulaski, and $y'/ Hr* Calkins. I viU not attempt to coaaent on the many positive aspects of your A,(' plant safety progr&a but will simply state that you appear to have a (m) very high quality program at your*location. All those interviewed J/ were obviously dedicated to improving the safety ana health of your 1 x employees. As a result of ay visit, X would like to reeoaaiend the following! 1. Add pulaonary function testing (spirometry) to your preplacecient and periodic lusJical eurveillanco program. Cpironutry is brconing increasingly accepted in industry as on3 tool to help monitor t-aployee health where irritant dusts or vapors are prgr-r.it. A review of your Workmen's Compensation, cases fron 9/3C772 to 9/30/73 revealed a total of seven cases of irritation to the rcr.piratory tract fron irritant fusts. Claims alleging aggravation of pre-exicting lung disease froa irritant custa or fuses are becoming iccreaeinrly coupon in industry today. Wa rocomecd that only tvo simple testa, th9 i'VC (forced Vital capacity) and l'i//i#o (forced expiratory voluae in cno tjcond) be used on the preplaceaeat evaluation and an nually cn all tuployeos. `fhcsw tests nru cir.ole, relatively inexpensive, and could be done in your own nzdical facility by the plant nurse* While not diagnostic, these t<53ts would bo a valuable) tool to the examining chysiciaa in monitoring the pulcanary health of your employees. AP00001935