Document 3enB775DX0NxxBM8YDNxR1vKx

o> {RECTORS 1RSR-7R MAfcCUi, V. REV, M.C., Chairman Buru of Occupational Safety 8 Health U. S- Pubhc Health Service .12720 Tw inbrook Parkway Rockville, Md, 20852 el. 301 - 496-89J5 rEDWARD J. BAIEK, Pa** Cheirman Division of Occupational Health Pennsylvania Department of Health Harrisburg, Pennsylvania 17120 Tel. 717 - 787*5237 ANDREW 0. HOSEY, Vice Chairman Bureau of Occupational Safety 8 Health U. 5- Public Health Service 1014 Broadway, Cincinnati, Ohio 45202 Tel. 513 - 684*2692 HOWARD E. AYER, Vice Chairman-elect Bureau of Occupational Safety 8 Health U- S. Public Health Service 1014 Broadway, Cincinnati, Ohio 45202 Tel. 513 -- 684-2688 AMERICAN CONFERENCE of GOVERNMENTAL INDUSTRIAL HYGIENISTS tOARO Of DIRECTORS 1WS-7S IRVING H. DAVIS Division of Occupational Health Michigan Department of Health 3900 `North login Street Laruing, Michigan 48924 HURON L. VAUGHAN Mississippi Division of Occupational Health P. 0. Box 1700 Jaduon, Mississippi 39205 JEREMIAH R. LYNCH Bureau of Occupational Safety 8 'Health U. S. Public Health Service 1014 Brotdwey, Cincinnati, Ohio 45202 VERNON E. ROSE, Secretary-Treasurer Bureau of Occupational Safety 8 Health U. S. Public Health Service 1014 Broadway, Cincinnati, Ohio 45202 Tel. 513 - 684-3557 Mr. Richard Henderson Manager, Environmental Hygiene Services Olin Research Center 275 Winchester Avenue New Haven, Connecticut 06504 Dear Dick; The TLV Committee met last week with V. K. Rowe present and final decision for the TLV fo*'"VINYL CHLORIDE was 200 ppm. This, as you will note, was the essential recommenda^iiL_af--MCCTiier at the Gordon Conference in 1968. Apparently, Dow hasn't seen any new evidence to alter this tentative reconmendation. Yours sincerely, HESTOKINGER: em Herbert E. Stokinger, Ph.D. Chairman Threshold Limits Committee OLI 1560 Reprinted From The Journal of The American Medical Annexation Aufiut 2J, 1967, Vol. 80J, **>. 577SS1 Copvright 1967, be American Medical Amciation Occupational Acroosteoly 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 workman derma. Some have clubbing of the fingers. Only a few associated with vinyl chloride (CH2CHCI) 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 (CH2CHC1). 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. Keprint requests to 500 S Main St, Akron, Ohio 44318 (Dr. Wil son). Acroosteolysis is a rare clinical entity, with only 72 cases of the familial type reported up to 1965, ac cording to Cheney in his 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 OLI 1561 578 ACROOSTEOLYSIS--WILSON 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 al2 (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 Finding* Symptom* Acroostaolysi* without Raynaud's symptoms, ona hand Acroostaolysis without Raynaud'a symptoms, both hands Acroostaolysis with Raynaud's symptoms, on* hand Acroostaolysis with Raynaud's symptoms, both hands No. of Casas 4 5 5 17 Total 31 Clubbinc of Angara Skin nodulaa 8 8 2. Mild stage of acroosteolysis with half-moon de fect of distal phalanx of mid finger. 1. Acroosteolysis with involvement of distal phalanges of all fingers. OLI 1562 JAMA, Aug 21, 1967 Vol 201, No 8 ACROOSTEOLYSIS--WILSON ET AL 579 istal phalanges, or a so-called slice effect along one r more of the tufts. 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 tire 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 3. Above, Acroosteolysis with merited fragmentation of diatal phalange* in November 1965. Below, Same individu al in November 1966. JAMA, Aug 21, 1967 Vol 201, No 8 __ OLI 1563 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 aT contains no specific information, and merely alludes to some hand problem. That of Cordier et al* 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 (CH2CHC1)* 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 tafMMNMi 4croo*t--lyil* . ,, _ mttout With fc*P Raynaud1* Symptom* Raynaud1* Symptom* 20-29 1 * 30-39 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 or who process it into plastic prodducts. No coses 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 (polymerizen) 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 roentgenographic changes. Right, Same individual one month after crushing injuiy to midfinger. ! AM A A ACROOSTEOLYSIS--WILSON ET AL 881 Epidemiology We have attempted to study the relationship of job history to the occurrence of the disease. Twen ty-seven of our 31 cases have either been on the "polycleaner" job assignment at the time the syn drome 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.--It 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 poly cleaning experience. Comment To our knowledge, this is a unique and, with the exception of references 3 and 4, previously unre ported disorder. The specific 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 specific. 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 "polyclean- 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 Byndrome. Figure 4 (left) shows an x-ray film of the left hand of the first of these cases of acroosteolysis (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 polycleaners 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 of 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 specific 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, W.D.; Acro-oeteolysis, Amer J Roentgen 94:595-617 (July) 1965. 2. Andren, L., et al: Osteopetrosis Acroosteolytica: Syndrome of Osteopetrosis, Acroosteolysis and Open Sutures of Skull, Acta Ckir Scand 124:496-507 (Dec) 1962. 3. Suciu, I.; Drejman, I.; and Valaakai, M.: Contributii Studiul Imolnavirilor Produse de Clorurs de Vinil, Med Intern 15:967978 (Aug) 1963. 4. Cordier, J.M., et al: Acroosteolyse et Lesides Cutanees Associees Cbez Deux Ouvriers, Affects* au Nettoyage D'Antoclaves, Cah Med Travail 4; (Jan) 1966. JAMA, Aug 21, 1967 Vol 201, No 8 OLI 1565