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COMMONWEALTH OF PENNSYLVANIA Department of Labor and Industry RALPH M. BASHORE, Secretary Special Bulletin 7V[o. 43 A Preliminary Report OF THE Dermatological and Systemic Effects of Exposure to Hexachloro^Naphthalene and Chloro-Diphenyl BUREAU OF INDUSTRIAL STANDARDS RAYMOND J. NICAISE, Director Harrisburg, Pennsylvania March 16, 1936 DSW 254920 STLCOPCB4060611 COMMONWEALTH OF PENNSYLVANIA Department op Labor and Industry A Preliminary Report of the Dermatological and Systemic Effects of Exposure to Hexachloro- Naphthalene and Chloro'Diphenyl By WILLIAM B. FULTON, M. D. Chief of Industrial Hygiene JULIA L. MATTHEWS, Ph. D. Chemist Industrial Hygiene Section Bureau of Industrial Standards DSW 254921 STLCOPCB4060612 A Preliminary Report of the Dermatological and Systemic Effects of Exposure to Hexachloro-naphthalene and Chloro-diphenyl. Introduction The demand in industry for electric insulation with fire-resistant and water-proof qualities has led to the use of increasing quantities of chlorinated naphthalenes and chloro-diphenyl. While the dermatological effects of other closely related organic chlorine substitution compounds have been studied, there is little mention in the literature of hexachloro- naphthalene and chloro-diphenyl. As early as 1918 VVauer (1) de scribed a condition which he termed "Pernakrankheit," resulting from exposure to perchloro-naphthalene. Teleky (2) found that the gravity of `the injuries and the clinical symptoms would appear to depend, in direct proportion, on the halogen content of the chlorinated derivatives. In 1929, J. Nicolas and J. Lacassagen (3) reported a man suffering from chlor-acne of the greater part of the body. These investigators were able to distinguish it from ordinary acne as a result of the localiza tion of the former. ' At the last meeting of the American Public Health Association at Milwaukee, Louis Schwartz (4) reported the 'occurrence of "an acne like condition of the exposed parts and sometimes of the covered parts, if the fumes penetrate the clothing, of 'workers exposed to the volatile fumes of these substances." In his paper he stated that patch tests with these substances give negative results. Chemical and Physical Properties Chlorinated naphthalene and chloro-diphenyl are organic substitution products. Under trade names they are sold to industry either in the solid or liquid form, combined with other plasticizers such as resins, waxes, and pitch compounds. The base of the products encountered in this investigation was hexa chloro-naphthalene with chloro-diphenyl present in amounts not over ten per cent. The addition of the latter to the synthetic wax tends to lower the melting point of the compound. Synthetic dyes, added in quantities of less than one per cent, give the desired color to the different products. The compounds have a faint aromatic odor, are insoluble in water and are unaffected by dilute acid and alkaline solutions. They are, however, soluble in organic solvents, such as carbon tetrachloride, naphtha, benzol, acetylene tetrachloride, acetone, gasoline, etc. The melting and boiling points of these compounds are dependent on the nature and amount of the different ingredients present and vary between 140-275 F. and 500-752 F., respectively. In their fluid or molten state the waxes have a very low viscosity and readily impregnate textile fabrics. Some of the chlorinated products contract only slightly 'during solidification, have a low coefficient of expansion as compared with natural waxes, and are non-inflammable. 3 DSW 254922 STLCOPCB4060613 Plant Process The fabric covering of wire and cable in the plant studied was im pregnated by passing the wire to be insulated through the melted wax or by immersion of the material in a solution of the wax. In the former method the operating temperature of the wax was maintained at 270 F. at which temperature volatilization and condensation of the wax oc curred. In the latter method impregnation was effected by passing the wire through a solution of the wax, in either toluene or a mixture of carbon tetrachloride and ethylene dichloride, at room temperature. Medical Findings Little mention is made in the literature concerning the systemic ef fect as a result of exposure to hexachloro-naphthalene and chlorodiphenyl. That the dermatitis resulting from exposure to these chlor inated derivatives can be produced by skin contact with them, mav best be illustrated in the presentation of Case Number 26 (See P. 12). What role the effect of the absorption, ingestion, and inhalation of these com pounds has, in combination or separately, deserves more detailed study. Whether they mav be considered as etiological factors to the production of acute yellow atrophy of the liver has not been determined. TABLE 1. NUMBER AND PERCENTAGE OP PERSONS SHOWING CHLOR-ICNE ACCORDING TO DEGREE OF SEVERITY Degree of Severity Number of Persons j Per cent of Persons Male Female Male Female Negative . Doubtful . Mild ......... Slight ... Moderate Advanced Totals 21 2 17.6 35.0 -- 2 -- 25.0 41 2 34.4 23.0 30 2 25.2 25.0 7 -- 5.9 -- 19 - 16.0 .... 118 99.1 100.0 Physical Examination--A partial physical examination was made on one hundred and one persons, who were exposed to either the solid, liquid, or vapor state of the wax. Of this number seventy-eight per cent were found to be affected with the dermatitis. A second group with well defined dermatoses was selected for complete physical examination in an attempt to determine, the presence of any systemic effect. In the latter group were twenty-three men (two of whom were controls) and two women. Table I shows the occurrence and degree of severity of the dermatitis in both groups. Any correlation of the incidence of the dermatitis according to operations in the plant studied w'as found to be impractical, as a result of frequent transfer of the workers from one op eration to another. Those persons having the greatest exposure con ' '4 DSW 254923 STLCOPCB4060614 stituted only twenty-six per cent of the total group examined and may account for the relatively low percentage of those having a moderate or advanced dermatitis. In the group of twenty-five selected for complete physical examina tions only those persons with a well defined dermatitis were chosen. An attempt was made to obtain those individuals with long exposure and those with exposure of shorter durations. The average length of ex posure of this group was 24.3 months. Table II shows their age dis tribution and it will be noted that eighty-seven per cent of the total group examined were under forty years of age. TABI.E II. PERCENTAGE DISTRIBUTION BY AGE OF THE GROUP GIVEN COMPLETEPHYSICAL EXAMINATIONS Exposed Controls Aee Group (Years) Male Female Male Female i Number Per cent Number ; Per cent Number j Per cent Number Percent Under 20 ......... . .... 20--20 ................ . 30--39 .................. 40--49 .................... Total1* ....... 1 4.S 11 52.4 6 28.6 3 14.3 21 100.1 ___ i 2, __ 100 2 1 100 i. 1 j 50 1 J 50 2 1 100 ___ ___ ___ .... .... ___ The length of exposure before the appearance of the dermatitis, which factor was found to be somewhat dependent on the severity of the ex posure, is shown in Table III. In only one person, who was in direct contact with the vapors of the hot wax, did the chlor-acne appear before two months exposure. Fifteen months were required for the earliest manifestation of the dermatitis in two other cases, each of whom had a more remote exposure, while the average length of exposure for the en tire group was approximately 5.9 months. TABLE III. NUMBER AND PERCENTAGE OF PERSONS SHOWING THEIR LENGTH OF EXPOSURE BEFORE FIRST APPEARANCE OF THE DERMATITIS Months of Exposure Male | Number I Per cent l .................... o 3--6 _________ 7--12 ________ Over 12 _____ Undetermined Totals ... .............................! 1 5 6 5 2 2 21 5 4.S 23.8 23.6 23.8 9.5 9.5 100.0 Female Number Per cent __ __ 1 50 ---- ---- ~1 50 2 100 DSW 254924 / / it V-3 STLCOPCB4060615 A complete history, which included chief complaints, objective symp toms, previous illnesses, family, personal, and occupational histories, was obtained' from each individual. Particular attention was given, in ob taining the history, to the individual's susceptibility to skin diseases. A preexisting acne vulgaris was present in one person, who noted as a re sult of his exposure, an accentuation of his symptoms. Symptoms refer able to the skin were usually given as chief complaints. Table IV gives the percentage frequency of objective symptoms as compared with the degree of involvement. Pruritis, remissions, and pro gressiveness of the dermatitis, were the objective symptoms most fre quently elicited. Sensory disturbance of the skin was present in only one individual. A small area on the anterior thigh of this worker showed a loss of heat and cold sensations. Two men, included in the group given a partial physical examination, complained of the rancid odor associated with sebaceous secretions. TABLE IV. NUMBER AND PERCENTAGE OP PERSONS1 HAVING SYMPTOMS INDICATED, AS COMPARED WITH THE DEGREE OP INVOLVEMENT Degree of Involvement Symptoms Advanced Moderate Slight i Number Per cent Number Per cent Numb .r | Per cent Remissions ...............................-.............. Pruritfs of Skin .................................. Progressive Dermatitis ........... .............. Lassitude --........-................-.................Burning of Skin ...... ............................... Pustular Stage Painful Constipation Polyuria -......................... ........................ Insomnia ............................ .................... Abdominal Pain ....................... --..........Diarrhea .... ............................................... Headache ........... ............................... ........ Sensory Skin Disturbance .................. 12 12 5 4 3 5 2 -- 1 -- -- 1 - 92.3 1)2.3 38.5 30.8 23.1 38.5 15.4 .-- 7.7 -- 7.7 .... 2 0 1 1 ~ __ ... 1 1 - i 100 7' .5 100 0 75.0 50 5 62.5 50 3 31 5 3 37.5 -- -- - 1 12.5 50 I 12.5 50 -1 "' i 50 : - .... .... 12.5 .... .... 1 Two male controls had none ol the above symptoms. Two females, with slight dermatitis, are Included. Evaluation of symptoms referable to other systems and regions, as a result of'additional exposure of the group to organic solvent vapors (tol uene or a mixture of carbon tetrachloride and ethylene dichloride), is difficult. Each person given a complete physical examination was at work on the day of the examination. Data was obtained on present and greatest weight and showed practically no variation. Five minute oral tempera tures were found to be normal. Examination of the head and neck was 6 DSW 254925 STLCOPCB4060616 essentially negative in the entire group except for the presence of cervicle adenopathies in a few cases. In one individual a small pedunculated tumor, which developed following trauma to a papule, was found in the region of the right temple. The tumor was spherical in shape, about the size of a large pea, and was attached to the skin by a pedicle. Its surface, devoid of hair, was marked with indefinite convolutions. The tumor was reddish in appearance and showed signs of inflammation of one of its lobulations, the result of an injury produced by scratching. Physical examination of the chest was essentially negative in the en tire group. The pulse and respiratory rates, obtained with the indivi dual at rest, and blood pressures, recorded with a standard mercury svphgnomanometer, were found to be within normal limits. Observations were made particularly for evidence of tenderness or muscular rigidity over the region of the liver during abdominal exam ination. This condition was found to be present in one individual, whose liver margin could not be palpated. Other clinical and laboratory find ings in this case failed to indicate additional evidence of liver damage. TABLE V. NUMBER AND PERCENTAGE OP PERSONS HAVING CHI,OR-ACNE OV THE INDICATED BODY SURFACES `' Body Surfaces Number of Persona Per cent of Persons PACE ......................... Cheeks .................. Forehead _______ Angle of the Jaw Cheek Prominence All above Surfaces NECK .................. Posterior __ Anterior ____ Both Surfaces ARMS ____ Extensor Plexor . FOREARMS ____ Extensor ____ Plexor ______ Both Surfaces OTTFST ._ . Upper Sternum -------- ----------- ----------- ------------------------------ Pectoral Region ________ _______ ________________________ Both Surfaces ______ ____ ____ __________ ABDOMEN ___________________________________ -.................. Recti ...........-____ _______________ Planks ___________ _____________________________________ back Scapulae Thoracic Lumbar All above ............................................................ ______ _____ ______ _________________________ Surfaces ----- ----- ----------------- ------------------------- BUTTOCK ______ ____ ___________________ _________________ THIGHS ........-............-............................... --........................... Extensor --------------------------------------------------------------------- Flexor ....................... ........................---------------------- ----------Both Surfaces _________________________ _____________ -- Extensor ................ ............................--------- ----------------------Flexor ...______________________ _______ ---------- ---------- 7 22 19 19 11 6 5 18 16 12 10 19 19 15 14 21 12 10 4 2 9 9 - 18 18 2 2 i 6 16 12 8 4 7 7 -- DSW 254926 95.5 82.5 82.5 47.7 20.0 21.7 78.1 69.4 52.1 43.4 82.5 82.5 65.1 60.8 8.7 4.3 52.1 43.4 17.4 8.7 39.1 39.1 --- 78.1 78.1 3.7 8.7 4.3 26.0 69.4 52.1 34.7 17.4 30.4 30.4 -- -1 J ilia STLCOPCB4060617 Examination of the skin was made with the subject stripped and ex posed to an excellent source of light. Of the entire group, thirteen, or tifty-six per cent, were found to be in the advanced stage of the derma titis, while the remainder had it to a less marked degree. Four distinct lesions of the chlor-acne were noted, all of which were present at the same time in the moderate and advanced cases. However, in the early stages, comedones and small papules made their appearance, while at later stages, pustules and sebaceous cysts of the skin occurred. Healing, following the pustular stage, usually occurred in a similar manner as the same process in acne vulgaris. At this stage dried serum was found over the pustules which had been 'traumatized. As healing progressed, slight scaling of the skin was noted over the site of the pustule. The scales were usually very small and dry in character. Tendency to in creased oiliness of the skin was not evident. Pitting of the skin was found in fourteen persons, or 60.8 per cent of the group, and the site most frequently affected was the posterior lateral neck. In these cases there was evidence of depigmentation in the cicatricial tissue. A predilection of the dermatitis for the extensor surfaces was especial ly evident on the arms and forearms, and to a lesser extent, on the thighs and legs in the group given complete physical examinations. Table V shows the percentage frequency of the chlor-acne for various regions of the body. When tire dermatitis occurred on the face and neck it terminated at the hair line and in no instance was the scalp in volved. Gross involvement of the sebaceous glands of the nose was absent, a tendency to diminution in the intensity being apparent at the mid-line of the face. In a few cases comedones were present on the dorsal surfaces of the hands and feet. In the group 'examined differences of complexion apparently had little effect on the susceptibility. The influence of age and sex on the indi vidual's susceptibility was not determined, for the greater number 'of those examined were between the ages of twenty and thirty years, and only two women were found working in the plant who had definite ex posure. Laboratory Findings--Appreciable changes were not evident in the erythrocyte and haemoglobin determinations. The total average leucocyte count was unchanged except for a slight increase in the group having an advanced chlor-acne. In this group the average leucocyte count was 11,130 cells per cubic millimeter, without a corresponding average increase in the polymorphonuclear leucocytes. Routine examination showed albumin in the urine of three persons, who were twenty-five years of age or less, as the only evidence of 'renal pathology. The icterus index and Van den Bergh determinations were made with a Klett colorimeter and the results are given in Table VI. Coincident with the time the first tests were made, all operations 'of the plant were stopped, so that those persons (10 in the exposed group and 2 controls) showing an icterus index greater than the upper normal limit, were per mitted a week's rest at home. At the end of this period, a second deter mination was made, and in practically every case the icterus index had returned to normal. 8 DSW 254927 STLCOPCB4060618 STLCOPCB4060619 TABLE VI. RESULTS OP ICTERUS INDEX AND VAN DEN BERGH DETERMINATIONS J First Determination 1 1Second Determination Case Icterus 1i Index Van don Bergh-- mgs. bilirubin per 100 e.c. Icterus Index Van den Bergh-- mgs. bilirubin per 100 c.e. 1 .................................... 3 ________ ___________ 4 ........... .................... -- 5 -______ G .................................... 7 ...............-................... 8 .................................... 9 .................................... 10 -----------------------------11 .................................... 12 .................................... 13 .................................... 14 -------- -------- -.............. 15 .................................... 1G .................................... 17 (Control) _________ 18 (Control) ............. -- 10 3 .................................. 20 .................................... 21 ...............................-- 22 .................................... 23 ..........-........................ 24 -........... .................... 25 .................. ...............- 6-1 5f?.1 6.6 5.4 7.5 6.5 6.2 5.0 5.3 7.3 5.6 5.4 5.1 6.4 9.2 6.6 9.4 5.5 10.0 4.6 6.2 4.0 5.6 0.35 0.34 ___ 0_._33 0.37 0.32 6.36 ___ ____ 0.32 0.46 0.33 0.47 .... 0.50 --0.31 ___ -- 5.2 __5._2 __5.0 6.8 5.0 ___ 7.5 ___ _____ 4.5 5.5 _3.9_ ___ 4.8 ____ ___ ___ ' _____ __ 6_.3_4 _____ ___ 0.36 ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ -- 1 Second determination made after an Interval of seven days. * Determinations not made. * Second determination not made. Figures 1, 2, and 3, and a brief summary of the clinical and laboratory findings of three advanced cases are presented to show the nature of the dermatitis encountered in this study. Case Number 4--White male; complexion brunette; aged 26 years. Chief Complaint--"Pimples." Analysis of Chief Complaint--First noted the dermatitis about twelve months following first exposure. Eruption first noted on cheeks and then gradually spreading to forehead and neck. The dermatitis next made its appearance on the arms and anterior chest. Pruritis present particularly during hot weather. Notices remissions of two or three days. Notes persistence of papules for a period of six months. Burning sensation not present. States that the pustules are painful. Past Medical History--Essentially negative. - Family History--Negative. Occupational History--Negative. Physical Examination--Apparently healthy adult male. Height 67 inches. Weight 152 pounds (greatest weight 155 pounds). Pulse rate at rest: 78. Respiratory rate: 14. Blood pressure 142/94. Head and Neck: chronic right otitis media; cervicle lymph glands not palpable. Chest: normal shape; percussion normal; breath and voice sounds normal; no rales. Heart: apical impulse, 5th interspace midclavicular line; no murmurs. Abdomen: flat; no areas of tenderness or rigidity; no masses. Skin: comedones; papules; pustules; pitting of the skin especially prominent posterior lateral neck. Lesions especially prominent over cheeks, forehead, and posterior 10 DSW 254929 STLCOPCB4060620 STLCOPCB4060621 lateral neck. Upper Lip and Nose: clear. Arms: all stages of dermatitis present over extensor surfaces. Forearms: relatively unaffected except for a few comedones over extensor surfaces. Chest and Back: occasional comedo, papule, and pustule, particularly over upper portion of the sternum and over scapulae. Abdomen: all stages of dermatitis over both recti. Thighs: distribution on extensor surfaces. Buttock: dermatitis present and uniform both sides. Legs: rare comedones over extensor surfaces. Scalp: clear. Hands, Feet, and Nails: negative. Laboratory Findings--Blood Examination: erythrocytes 4,940,000; leucocytes 9,050; haemoglobin 100. Differential Count: polymorphonuclear leucocytes 66 per cent; small lymphocytes 12 per cent; large lymphocytes 20 per cent; basophiles 0.5 per cent; eosinophiles 1.5 per cent. Icterus Index 5.1. Urinaly sis: reaction acid; specific gravity 1.020; albumin negative; sugar negative; microscopic examination, many pus cells in small clumps; no casts; no erythrocytes. Case Number 5--White male; complexion blonde; aged 24 years. Chief Complaint--'"Pimples." Analysis of Chief Complaint--Dermatitis developed about three months after first exposure. Eruption first noted on face at the angle ot the jaw. Noted gradual extension of the condition over the rest of the face during a period of one month's time. Dermatitis next involved the arms and neck. Pruritis noted at times especially after hot bath or in warm weather. Burning sensation not present. Remissions of two or three days. Past Medical History--Usual childhood diseases. Family History--Essentially negative. Occupational History--Negative. Physical Examination--Apparently healthy adult male. Height 68 inches. Weight 132 pounds (greatest weight 140 pounds). Pulse rate at rest: 70. Respiratory rate: 16. Blood pressure 140/80. Chest: normal shape; per cussion normal; breath and voice sounds normal; no rales. Heart: apical impulse, 5th interspace midclavicular line; no murmurs. Abdomen: flat; no areas of tenderness or rigidity; no masses. Skin: comedones; papules; pustules; pitting of the skin. Face: dermatitis pronounced over the angle of the jaw and cheeks. Neck: posterior lateral neck most markedly in volved. Chest and Back: essentially negative. _ Arms and Forearms: dis tribution of dermatitis noted over extensor surfaces but less marked on the forearms. Thighs : small patches present anteriorly above the knees. Legs : essentially negative. Hands, Feet, and Nails: negative. Scalp: clear. Laboratory Findings--Blood Examination: erythrocytes 5,190,000; leucocytes 9,050; haemoglobin 100. Differential Count: polymorphonuclear leucocytes 67 per cent; small lymphocytes 25 per cent; large lymphocytes 4.5 per cent; eosinophiles 3 per cent; basophiles 0.5 per cent. Icterus Index 6.6; Van den Bergh 0.33 mgs. bilirubin per 100 c. c.; icterus index (7 days later) 5.0. Urinalysis: reaction acid; specific gravity 1.015; albumin 3 +; sugar negative; microscopic examination negative. Case Number 26--Infant male; complexion blonde; aged 2y2 years. History Obtained from Mother--Child's father had been working at the plant for about two months when the mother first noticed development of the dermatitis. Mother stated that the child's father returned home in his soiled working clothes and that it was his habit to play and romp with his son, without changing to clean clothing. She also stated that father and son slept together, the father always sleeping in his underwear. The dermatitis made its first appearance on the child's anterior thighs above the knees. She next noticed small patches on the flexor surfaces of the forearms which gradually extended to the extensor surfaces. Finally, the dermatitis 12 DSW 254931 STLCOPCB4060622 Figure 3--Case Number 26. DSW 254932 STLCOPCB4060623 developed on the neck and face. Mother stated that she noted child scratch ing occasionally. She has noticed a diminution in his appetite. Constipa tion not present. No vomiting. Stools normal in color and consistency. No jaundice. No haematuria. No polyuria. Mother staled that child has been active, sleeps well, and is apparently unchanged except for the anorexia. Past Medical History--Pertussis at age of six months. Family History--Father suffering from generalized chlor-acne as result of ex posure to hexachloro-naphthalene and chloro-diphenyl. Mother shows der matitis : cheeks; buttock; and extensor surfaces of thighs. Sister, 11 months old, with chlor-acne in the comedo stage over both cheeks. Physical Examination--Well developed infant male. Weight 35 pounds. Axil lary temperature: 101. Pulse rate at rest: 140. Respiratory rate: 26. Head and Neck: essentially negative except for acute left otitis media; ante rior cervicle lymph glands palpable. Chest: normal shape; breath and voice sounds normal; no rales. Heart: no apparent enlargement; no murmurs. Abdomen: convex; no tenderness or rigidity; liver edge not palpable. Ex tremities : negative. Skin: comedones; papules; pustules; slight pitting of the skin. Face: comedones and papules abundant over cheeks and forehead. Nose and Upper Lip: relatively unaffected. Neck: anterior and posterior neck involved with occasional pustule. Arms and Forearms : all stages of the dermatitis present particularly on the extensor surfaces. Chest: few comedones over superior portion of the sternum. Back: few comedones and papules over scapulae. Abdomen : essentially negative. Thighs: dermatitis present on both lateral and anterior surfaces. Legs: occasional comedones over extensor surfaces. Scalp: clear. Hands, Feet, and Nails: negative. Prevention The production of industrial dermatoses is partially dependent upon the nature and severity of the exposure and upon individual susceptibil ity. The relatively high percentage of those individuals affected, follow ing exposure to hexachloro-naphthalene and chloro-diphenyl, in a total group of one hundred and twenty-six persons examined, indicates a need for the adoption of preventive measures where these compounds are used in industry. Prevention of skin contact with these substances would depend somewhat upon the process employed. In those processes where the compounds are heated to a temperature sufficient to cause volatiliza tion and subsequent condensation in air, either closed methods, operating under partial vacuum, or exhaust ventilation should be instituted. In those processes where the compounds are handled in the solid or liquid form, other means of prevention must be adopted. When the operation is such that contamination of the exposed portions of the body and clothing is unavoidable, adequate protective clothing, lockers, and other sanitary facilities, should be provided. Further prevention of skin con tact with these substances, for persons handling the finished product in the plant and for the consumers, could be had by application of pro tective coatings applied to the finished product. Summary 1. Hexachloro-naphthalene and chloro-diphenyl produce, on contact with the skir. of some individuals, an acne-like dermatitis after varying degrees of exposure. 14 DSW 254933 STLCOPCB4060624 2. From one to fifteen months exposure to varying amounts of hexachloro-naphthalene and chloro-diphenyl on the group examined was required before the onset of the dermatitis. 3. The dermatitis, in the group of twenty-three persons examined, resulting from exposure (average length of exposure approximately 24.3 months ) to hexachloro-naphthalene and chloro-diphenyl had a predilec tion for the face and the extensor surfaces of the body. 4. Systemic effects produced as a result of exposure to hexachloronaphthalene and chloro-diphenyl should be further studied. AC K N 0 W LEDGM E N TS The Department of Labor and Industry of the Commonwealth of Pennsylvania wishes to thank the management and employes of the plant studied for their cooperation and interest which made the success of this study possible and the laboratory technicians of the York Hospital for the icterus index and Van den Bergh determinations. Bibliography 1. Wauer: Ztrbl. f. Gewerbehyg., P. 100, 1918. Berlin. 2. Teleky, L.: Klin. Woch., Nos. 18 and 19, pp. 845; 897, 1927. Berlin. 3. Nicolas, T- and Lacassagne, J.: Bull. Soc. franc, de dermat, et syph., P. 223, March 1929; abstr. J. Ind. Hyg., 11, 187, 1929. 4. Schwartz, Louis: Unpublished paper--"Dermatitis from Syn thetic Resins and Waxes." Read October 8, 1935 at the Sixty Fourth Annual Meeting of the American Public Health Asso ciation in Milwaukee, Wisconsin. 15 25A93A STLCOPCB4060625