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PLAINTIFF'S EXHIBIT MET-302 Potential Jleattk Jfafondi the Jd&atlteA. PnduAtny W. J. McConnell, J. Wm. Fehnel and John J. Ferry Preprinted by permission of Journal of Industrial Hygiene end Toxicology Introduction are cut and stamped and either washed in drums to remove This report presents the results of a cross section study dirt or tied together and soaked for at least 24 hours in of the physical environment of the leather industry "soaking vats" containing water, or in pits in which a from the viewpoint of real and potential health hazardspaddle stirs the hides in the water. Germicides are used incident to manufacturing processes, and of practical meas in the water to further disinfect the hides and prevent ures of control. A total of 62 plants distributed in 10 putrefaction. They are then trimmed and green fleshed states was visited during 1939 and 1940, and inspected and run through the lime vats for the purpose of loosening Jy: possible health hazards. In the preliminary inspection, che epidermis or outer layer of skin in which the hair is samples of material handled or air analyses made at isolated embedded. There are several variations in the liming operations disclosed no significant hazard in some of the method. In some tanneries the solution used is a mixture plants, while in others extensive surveys were not possible of hydrated lime and dimethylamine which is added directly for some reason. In 38 plants, however, surveys with air and sodium sulfide which may be piped into or added analyses were subsequently conducted, the findings of directly to the vats. In others, a small quantity of arsenic which are recorded in this report. Included in the plants sulfide is used. This it weighed out by hand and added studied completely were 4 tanneries, 22 shoe factories, to the lime while it is being slaked. In some instances the 3 sole and heel plants, and 9 plants manufacturing mis hides are moved from one vat to the next by means of a cellaneous goods in connection with the leather industry. reel, thereby minimizing personal contact with the solution. In a few instances, where studies were conducted during After 3 to 10 days, the hides are removed, washed, and the summer months, a recheck, was made during the winter passed through the dehairing and defleshing machines. The months when the windows and doors were closed, so that hides are chen rewashed and beamed. In beaming, the fine a comparison in fume and dust concentration could be hair which escaped the machine is removed by means of made. a two-handled knife. The older method, which consisted of sweating the hides Leather Manufacturing Processes by means of slow decomposition of the surface for the Products Used purpose of loosening the hair and then removing it with With the exception of skins from kangaroos, reptiles, and marine animals, che majority of hides and skins used in the industry are by-products of animals raised for their value to man as beasts of burden and as dairy producers, or slaughtered for their meat. These include the hides and skins from cattle, goats, calves, sheep, horses, water buffaloes deer, and elk--all having marked differences and suitable for a variety of purposes. Since these skins and hides may come from every country across the earth, they must be preserved from decay, and therefore are shipped already treated with some one of the preservatives. In some cases, arsenic compounds are used. The hides re ceived at the tanneries are usually either dry-salted or green-salted, the latter being the more generally used method. Many chemical agents are used in modern tanning methods. In one plant, for example, more than 230 dif ferent materials are used in the production of the leather. These include alkalies, acids, chromates, vegetable and synthetic tanning materials, oils, finishes and dyes. While a blunt knife, was not encountered in the tanneries studied, although this method of removing the hair and flesh is said still to exist. After the hides have been properly dehaired and fleshed, they are placed in a bating solution, in either drums or paddle vats, to remove the lime. The bating solution contains usually ammonium chloride and an enzyme com pound. They are then pickled in vats containing a 1 to 2% sulfuric acid solution, to which sodium chloride has been added. They are again washed thoroughly in prepara tion for tanning operations and processes which convert them into leather. All hides and skins, whether they are to be tanned by vegetable or chrome agents, receive about the same treat ment up to this point. As a rule, the heavy leathers, such as harness leather and the majority of leathers used for luggage, as well as certain kinds of gloves and garment leather, are vegetable tanned. Chrome tanning is em ployed usually for shoe-upper leather made of cattle hides, goatskins and calfskins, and certain glove and garment certain of the dyes are derived from trees and plants, most of them are chemical products from the coal-tar com pounds. Petroleum, tallow, wool grease, neatsfoot, linseed and other oils and greases, properly treated, are used in making a variety of types of leather and for replacing the leather. Vegetable tanning consists of placing the hides and skins in tanning liquors of progressively increasing strength. Depending upon the desired results, this process may re quire from 2 to 6 months or longer. After passing through natural oil removed in the hides and skins as a result of the tanning process. Leather Making Processes the series of vats, the liquor of each increasing in strength, they are placed flat in lay-away vats into which the liquor solution is then pumped until the hides are covered. The hides then pass through a scrubbing machine to remove In order to convert the raw hides and skins into leather the last traces of sediment or excess liquor. The finishing they must first be restored to their original flexible condi operations vary depending upon the use for which the tion and the hair and flesh removed. The hides and skins leather is intended, but usually consist of restoring the are washed, fleshed, limed, bated, pickled, and tanned. They oiliness which has been removed by che tanning process. Reprinted from Shoe and Leather Reporter, August IS and September 19, 1492. The oil, or mixture of oils, is added to the leather while moist. The leather is then hung up to dry, generally in a darkened room, conditioned -with moisture and good air circulation. All chrome tanning processes are similar, but the solu tions used and the method of treatment may vary. There are two methods in common use, the "two bath" system and the more recently developed "one bath" system. In the "two bath" process the hides are placed in a solution of sodium bichromate and hydrochloric acid and milled, either in a drum or paddle vat, until the chromate has thoroughly penetrated the hide. They are then re moved from the solution, allowed to drain, and placed in a solution of sodium thiosulfate (hypo) and hydrochloric add for about 2 hours. The first bath saturates the hide with chromic oxide (chromic acid anhydride), and the second bath reduces the chromic oxide to basic chromic chloride, which, by the action of a sodium bicarbonate solution, forms chromic hydroxide, in which condition it will combine with the hide substance to form leather. It is while handling the hides saturated with chromic acid that formation of chrome sores or ulcers is most likely to occur. In the "one bath" process the dichromate is reduced directly, usually by means of sulfuric acid, sodium thio sulfate and sugar. The hides are then milled in this colloidal solution of basic sulfate of chromium until tan ning is complete. The "one bath" method is by far the more rapid, and, as it eliminates the handling of the hides saturated with chromic acid, is the less hazardous method. The syntanning method is one of the latest developments in the tanning industry. It is simply canning by means of the use of synthetic tanning agents. In one case the material used was an organic material prepared from sul fonic acid, caustic soda, Glaubers salt, formaldehyde, and water. The tanned hides or skins are then washed, drained and milled in the drums with fat liquor and pigments. The fat liquor consists chiefly of an emulsion of cod and neats- foot oil, either raw or sulfonated, and glycerine. The pigments are prepared in the pigment room and are carried in tubs and dumped into the drums. The leather is stuffed with oil which is done by wringing the hides or skins to remove excess water, sammying to the correct moisture condition and stuffing in drums. The stuffing material may include mineral grease, cod-liver oil, wool grease, tallow and a small amount of sulfonated codliver oil, or other similar materials. The mixture is heated to about 140F. with steam. The leather is placed in the drum and milled until saturated. The leather is then set, which consists of stretching the hide either by machine or hand to remove wrinkles and smooth out the grain, coated with an emulsion of wool grease and dried at 100F. in an air tunnel. Following these operations, the leather is worked by machine to break down the fibers and render it more pliable, known as jacking, and the outer grain side of the leather is scoured, usually by means of a car borundum paper covered drum, although revolving blades may be used. This latter operation is called buffing. Finishing may be done entirely by machine. The leather is passed through revolving rolls and contacts the finishing solution, which is fed into the trough of the machine and agitated continuously by an automatic stirrer. As the leather leaves the rolls, it passes over a conveyor belt where it is swabbed by a hand brush to secure even coating, racked, and placed in the drying chamber. A recent de velopment in finishing the leather is that of spraying. The finish solution may be applied either by a hand-operated spray gun or by a machine in which the leather is sprayed automatically as it moves along on an endless belt. From the viewpoint of health and safety, the machine spray is to be preferred. In this, the hides enter one end of a completely enclosed unit, and are sprayed and dried before being removed. The finish solution may contain one or more solvents, waxes and resins, soap, milk, Irish moss, formaldehyde and small amounts of fusel oil. Organic dyes and the mineral pigments also are used. After finish ing, the leather is burnished on wheels coated with car borundum paper, glazed, rolled and pressed. Large hy draulic presses usually are employed for leather pressing . Where the quality of luster in the leather is desired, the leather is subjected to a glazing process by being rubbed with a glass cylinder. By still further varying the finishing process, the bright surface of patent leather is obtained. This consists of coating the grain surface of the leather with a varnish or lacquer, which, when dry, forms a bright, hard material, flexible enough to bend with the leather. In this process the colored leather is passed through a degreasing operation in which naphtha removes the sur face grease. It is then stretched on frames and coated by hand with special paints or colors, usually a mixture of linseed oil and ocher materials, and the leather is either baked or exposed to sunlight and rubbed with pumice. This operation is repeated several times to ensure a finish which is bright and hard. Where suede surfaces are desired, the flesh side of the leather is buffed against a large rounded emery wheel which gives the leather the characteristic nap and soft texture of suede. Shoe Manufacturing Processes A variety of methods have been introduced and as many as 2,000 operations may be employed in making an ordinary shoe. Therefore, the processes observed in this survey can be described only in very general terms. Cutting Department The cutting of linings and upper parts of the shoe may be done by hand or by machine. Hand cutting is done on a hard wooden block, made especially for that purpose. The material is placed on the block and the pattern, which is made of metal or metal-bound template, is laid on the material, and the operator draws a short-bladed knife around the metal edge of the pattern. Machine cutting is done on a machine called the clicking machine. The leather is placed on the block and the operator sets a die upon the leather. He swings the beam of the machine over the die which is automatically pressed through the leather. The beam then returns to its original posicion.' The edges of the uppers are sanded or roughed, and may be sprayed with a lacquer before being sent to the fitting room. Fitting Department The upper leather, lining, tongue and fittings are sewed or cemented together. Sewing is done almost entirely by machine, while cement is applied by both machine and by hand brushing. Ornamental perforations are backed by means of a lacquered tape which is moistened in a solvent, usually butyl acetate. It was noticed that in many plants petroleum naphtha rubber cement is being replaced by latex cement. , Stock Fitting Department In this department the heeb, soles, insoles, and other shoe parts are prepared for use. The sole is rounded, or 2 cut co the desired shape, and sanded. It may be channeled, and, for certain type shoes, may be cemented, using either a rubber or a pyroxylin cement. Insoles are trimmed, sanded, and channeled. They are frequently stiffened by dipping in a solution of stiffening material in alcohol. The sock linings, slip soles, and leafs are cemented. In many plants, wooden heels are covered. The wooden heel is sanded and covered with either a leather or a celluloid cover. The leather covers are cemented in place with a rubber cement. The celluloid covers are soaked in a solu tion containing usually methyl alcohol, ethyl alcohol, ace tone, ethyl acetate, or a mixture of these and other solvents, dried between cloths and applied to a heel which has been previously covered with celluloid cement. The covered heel is then sprayed with lacquer. Listing Department In the lasting department, the uppers are joined to the insoles. The insole is tacked to the wooden last or, in some lasts, to lead "spots." These spots muse be renewed from time to time by scraping out the old lead and re filling from a pot of molten lead. The last and the upper are then placed together, and by passing along a series of lasting machines, the upper is drawn firmly over the last and held in place by wire or tacks. A box toe may be inserted to give stiffness to the toe. This is usually made of leather or composition, and before use must be softened by steaming, soaking in water, treating with solvents, or in the latest development by the use of phosphoric acid. Latex cement is frequently applied to the upper to aid in holding it firmly in place. Bottoming Department The rough bottom of the insole is ground to remove excess upper leather, and sanded to prepare it for cementing. The shank is nailed or cemented in place, and the bottom evened by applying a filler, usually consisting of ground cork and coal tar pitch. The outsole is then attached. This may be done by sewing, by cementing or by a com bination of the two methods. In some cases the outsole is attached to a welt which is fastened to the insole. The cement used may be either a petroleum naphtha rubber cement, or a pyroxylin cement. In making cripe soled shoes, a benzol cement is still widely used. The heel is then tacked in place and is trimmed and sanded. The sole edges are trimmed, sanded and set. Finishing Department The rough shoe is finished, polished, inspected and packed. The soles and heels are sanded and buffed. Stains and wax finishes are applied. Scratches are repaired when possible, and dirt is removed by soap and water, ammonia or any one of several solvents. Some shoes are sprayed with lacquer. The finished shoe is then polished and is ready for shipment. In this department, as many as several hundred different waxes, polishes, dyes, stains and solvents may be used. Sole and Heel Plants In only a few cases did the shoe factories produce their own soles and heels. These were usually purchased, or in the case of larger companies, prepared in a separate factory. The leather is dampened in water and the soles are cut out by machine. The soles are automatically cut or skived to an even thickness, and stamped to designate size and thickness. Heels are cut out by machine or by hand dies and mallets. The soles and heels are frequently water proofed by immersion in an oil bath. Some heels are pre pared from logs. The scrap leather is cut into sections and glued together under pressure in the form of a log which is then cue to the desired thickness. Rands, shanks and counters are cut from scraps, usually by hand mallet. The final scrap is baled and sold. Other Manufacturing Processes Shoe manufacturers frequently conduct a variety of other manufacturing processes which may involve addi tional health hazards. A number of companies operate their own tanneries. Some maintain a chemical plant en gaged in the production of materials used in the plants. These materials include rubber cements, dyes, polishes, soaps, rubberized cloth, and other materials. One company produces wooden lasts for use in various shoe plants. An other is engaged in the tanning and preparation of approxi mately 0 kinds of leather and operates a large harness and leather belt manufacturing plant, as well as a shoe manu facturing plant. A few of the plants included in the survey confine their operations to special manufacturing processes. One com pany manufactures leather goods, such as men's belts, gar ters, braces, etc. This company also operates a metal de partment where various ornaments and fastenings are stamped from metal, assembled, in some instances by soldering, and then plated and buffed. Copper, brass, nickel, bronze, gold, and silver plating are done. The buffing compounds used include one containing a high percentage of silica. A second company confines leather work to the manufacture of shoe writs, a leather strip used to attach the shoe uppers to the soles, and conducts a branch busi ness which involves the weaving of wool cloth and the manufacture of wearing apparel. A third purchases its leathers in the finished state and confines its operations to the manufacture of ladies' handbags from both natural and artificial leather. A fourth produces only upholstery leather. This company uses a variety of lacquers which are mixed in the plant. The hides, which are received tanned, are buffed and sanded to secure a smooth surface and even thickness, after which they are dyed in drums and tacked out for stretching and drying. A heavy dope coating is applied by hand. After drying, a color coating and a finish coat are sprayed on the hides. The various alcohols and acetates are the solvents used in the materials. Small quantities of methyl alcohol and benzol and larger quantities of toluol were found in the thinner and stock lacquer. Three other plants included could hardly be classified among leather manufacturers, since one is en gaged in the manufacture of leather and woolen clothing, and the second in the manufacture of rubber heels and soles and canvas shoes, and the third in the sizing and finishing of cotton cloth. Plant Conditions and Sanitary Facilities The tanneries inspected in this survey are housed for the most part in series of one and two-story frame or brick buildings. The ground floor usually is concrete and upper floors are of wood construction. Natural ventilation by means of windows and doors is utilized and results fre quently in drafty conditions during the winter months and high temperatures in summer. High relative humidities are usually present in the tanneries. A few of the tan neries, however, were of modern construction, well venti lated by mechanical means. 'While a number of tanneries inspected had artificial illumination consisting of incandescent bulbs, many of which were improperly hung and unshaded, resulting in annoying glare and substandard intensity, the four tan 3 t neries in which complete studies were made (See Table A on Page 5) were adequately illuminated, utilizing both windows and skylights for natural illumination and aug mented with well-shaded incandescent lamps of ample in tensity. In a few plants, fluorescent type lamps were used, particularly in inspection departments. Tanneries necessarily are odorous due to the nature of the materials handled. "While objectionable to the casual visitor, workers employed in the tanneries soon becomes accustomed to the odors and apparently are not affected by them. Much of the tannery odor is caused by de composing material which collects in cracks and corners. This odor can be reduced by frequent washing down of the floors and machines and by the prevention of accum ulation of hide trimmings. The chief agencies of injury in tanneries are the staking and fleshing machines, presses, beam cutters, moulding and embossing machines, and slippery floors. The types of accidents reported are those due to being "caught in or between" machinery, injuries to hands and fingers caught between moving parts, injuries due to striking against sharp objects, burning and scalding. Improper guarding of tanks is an important mechanical cause of serious acci dents, and may result in a worker falling into the tank and being scalded to death. Tanks should be entirely en closed. While safety devices have been installed and are maintained in some of the tanneries inspected, others have failed to avail themselves of these safeguards. Only a few of the tanneries studied maintain a plane dis pensary with a nurse in attendance and with adequate medi cal supervision. Others maintain a first-aid room made available to the management or certain employes having some knowledge of first-aid work for rendering emergency first aid to the injured. A number of these first-aid rooms, however, are not supplied with running water or with sufficient equipment, and are inadequately maintained. Shoe factories and other leather manufacturing plants usually are housed in multistory buildings constructed of brick, stucco, or wood. They frequently are built in the shape of a U or an H, which provides a minimum width of floors for good natural illumination and ventilation. The majority of plants maintain a good standard cff illumination and advantage is taken of natural daylight by frequent cleaning of windows. Shades, Venetian blinds, or awnings are used to control excessive glare. Natural illumination is augmented, where needed, by both general and localized lighting units. While natural ventilation by means of win dow control usually is utilized, air movement by means of electric fans is created during the summer months. Washing and toilet facilities are provided and as a rule are well maintained; but the equipment, though adequate, was outmoded in a number of plants. Drinking water is provided in most instances by iced bubbler fountains, elec trically cooled in several instances. It was noticed, how ever, in a few scattered plants that common drinking cups were in use. Housekeeping generally is good and the man agement is to be commended for the orderliness of material maintained in the various departments. Plant dispensaries, adequately equipped and with a nurse in attendance, are more in evidence in shoe manufacturing plants than in tanneries. The injuries reported consist largely of injuries to the hands and fingers from machinery and needles in sewing machines. Electric shock from oper ating cutters and clicking machines is always a possibility in cutting departments. Methods of Sampling and Analysis Atmospheric dust samples were taken at the breathing level of workmen at various operations, using the impinger1 and the midget impinger** for collecting the samples. The sampling solution used was either distilled water, alcohol or a mixture of the two, depending upon the type of dust present. Alcohol acts as a preservative to inhibit solucion of the fine particles and to prevent the formation of aggre gates of the fine particles by clumping. In taking the sample, the apparatus was set up at the desired location, and air was pulled through the impinger at a rate of 1 cfm., or 1/10 cfm. for the midget impinger. The source of suction was either an electrically driven or a hand-operated vacuum pump. The sampling period usually lasted from 30 minutes to an hour to obtain a sample showing representative conditions. Dust counts were made by the technique and methods developed and used by the U. S. Public Health Service. The organic solvent vapors were determined by the inter ferometer or the combustible gas indicator. These instru ments will show the total concentration of organic materials present in the air, but will not show what substances are present. Where the material being used was not known, or where there were several different solvents present, as in the case of lacquer, it was necessary to take a sample of the material being used for chemical analysis. Tests for hydrogen sulfide or hydrogen cyanide were made by instruments designed specifically for these two materials. Where it was necessary to determine the quantity of some toxic material present, as, for example, chromates, ammonia, formaldehyde etc. the sample was collected by bubbling the air through a suitable absorbing solution, using either the impinger or the fritted glass bubbling tube, and the material was determined by chemical analysis. Health Hazards Tanneries Anthrax, a relatively rare yet serious infection when it occurs, may be contracted by workers from handling hides and skins imported from countries where anthrax among animals is prevalent. In a survey of anthrax reported by the several states, Smyth,' secured a record in the years 19341938 of 375 cases of which SI were fatal. Workers in hides and skins accounted for 93 cases and 6 fatalities; the largest for any of the industrial groups listed. The anthrax organisms enter the body usually through skin abrasions, such as cuts, scratches, or minor injuries, forming a malignant pustule of the skin at the point of entrance. Any small pimple, boil, or eruption appearing on the skin of the tannery worker should be seen imme diately by the plant physician, and any worker with open cuts or sores on the exposed parts of the body should be kept out of contact with hides, hair, and wash water until completely healed. Antiserum should be employed if anthrax is suspected. LU. S. Public Health Service, Public Health Bulletin No. 217, ! 9s r, J. J. Bloomfield and J. M. Dallavalle, Determination and Control of Industrial Dusts. * U. S- Bureau of Mines, Report of Investigations 3)60. December, 19)7, Bureau of Mines Midget Impinger for Dust Sampling. 'American Public Health Assoc., Pittsburgh, Pi.. Anthns (A Twenty-year Survey of Anthrax in the U. S.)--Sixth Report of the Committee on Anthrax, Industrial Hygiene Section, October >1 published in American Public Health Assoc. Year Book. im t*o 4 Other skin infections, caused by the leu dangerous pusproducing organisms, following skin injuries, are hazards present in all tannery jobs. An analysis of the number and cost of compensated infected injuries in 1932 by the Divi sion of Statistics and Information of the New York State Department of Labor, showed that 2J% of the compen sated cases in the leather industry were infected injuries, where the proportion of workers thus infected in all in dustries was only 1J.3%. The proportion in the leather industry was the third highest among the 3 6 groups reported upon. Skin irritations from contact with a variety of chemical substances are frequent complaints among tannery em ployes. Since tanning processes are not completely stand ardized and vary with the manufacturer and with the type of leather manufactured, the chemicals used likewise vary as indicated elsewhere in the report. It is impossible in many instances to determine the particular chemical or mechani cal agent responsible for initiating the skin irritation. The usual site of these skin irritations is first on parts of the body most exposed to direct contact with the irritating substance. Other parts of the body may be affected when the clothes are penetrated by the material. Caustic and acid bums are common. In chrome dermatitis the site of the lesion is practically always where the skin has been broken or injured. The lesions may appear as single or multiple ulcers, called "chrome holes" which may extend to the underlying tissues. Occasionally, irritation of the mucous membranes of the throat and nose, and even per foration of the nasal sepcum, may occur from inhaling chromic add fumes liberated in the chrome tanning process or from direct contact with the chromates. Other tanning agents, such as oak, sumac, and synthetic tannins may cause skin affections, as may also the various solvents, dyes, soaps, and oils used in certain processes. Some merely produce a redness of the skin, while others cause swelling and blisters in the early stages followed by peeling, crusting, and thickening of the skin in the later stages. The appearance of the lesion, however, seldom suggests a clue to the responsible irritant. Skin affections as well as systemic poisoning may result from handling hides and skins which are treated with arsenic or mercury as preservatives. Arsenic also is sometimes used in dehairing processes. Harmful amounts of hydrogen sul phide may be present in box can bringing skins and hides to the tannery and in cellars and hide houses in which they are stored. Workers engaged in cleaning sewer traps and sump tanks which collect waste material have been affected by hydrogen sulphide gas liberated from putrefaction of the fleshy materials. TABLE A (See Page 4) Grouping op Plants Number of Employees Per cent Female Pleat Sinication Plants According to Type of Total 100 200 100 Housekeeping Personal facilities Lighting Product Manufactured Less and and end Under 10% than under under over 30%and Excel- Can- Excel- Excel- 100 200 100 over lentGood Fear gesced lent Good FairPoor lent Good Fair Poor Tanneries .................-........ 4....................................................................................................................................................... UpperLeather ............ 2.................. 2 1 1 1 1.. .. 1 1.. .. 1 1 ......... Leather ........................... Leather, calf, miscellaneous ................ Shoe factories .....--........... Women's Shoes ................ Men's Shoes ................... 1 1 .. .. 1.. '1 1 .................... 1 1 11 1 1 .................... 1 22....................................................................................................................................................... 14 ... . 6 8 .. 14 3 8 2 1 1 12* .. .. 212.... 4.. .. 2 2 3 1.. 4 2 2.. .. 35 .. .. Canvas Shoes ................. 4 f t t Children's and Infants' Shoes ...._..................... 1 .. .. I . . t t .. 1 .. 1 .................... 1 .................... 1 .................... 1 .................... 1 1 .. .. Partial Survey .............. Sole and heel factories____ Leather Soles, Heels and Counters ............ Miscellaneous ................ .. Rubber Soles and Heels Sized and Finished Cotton Cloth ......... -- Leather and Wool Clothing Beltj and Straps ............ Finished Upholstery Leather ....................... Welting and Textiles .... Handbags ......... .............. Dyes, Polishes, Cements 2 t t t t tt t t t t t t t t 3....................................................................................................................................................... 3 .................... 3 3 3 .................... 2 1 411 9....................................................................................................................................................... 1 .................... 1 1 1 .................... 1 .................... 1 1 1 ............................. 11 1 .................... 1.. 1 11 1.. 1 .................... ............................. 1 .................... 1 .................... 1 1 1 .................... 1 ... . 1 .................... 1 1 .................... 1.................. 1 1. .. 1. 1 1 .................... $ .. .. 1. 1.. . 1 .................... 1 .................... 1 ............................. 1.. .. 1 .................. 1 .................... 1 .... 1 .................... 1 1.. 1.. 1.. .. .. .. Lambskin ..................... 1 t Grand total plants ....... 38 t t t t t t t t t t ttt *One plant not recorded under personal facilities. $One plant not recorded under lighting. ?Not recorded. None. J Varying Temperatures, Humidities, and 'Wetness Until complete mechanization of all wet processes in tan neries is attained, exposure of certain workers to wetness is unavoidable. Other workers whose duties necessitate enter ing the hot drying rooms are exposed to high temperatures, and processes in which steam is used add moisture to the air. During cold weather low temperatures and drafts are common in sections of the plant. Some foreign observers have reported that rheumatic af fections are especially prominent among those working in wet processes and that illnesses due to chills and respiratory diseases are above average. Preventive Measures A program of preventive measures against skin affections among tannery workers include a minimum of handling hides as they are transferred from vat to tank, and from tank to rack, and the maintenance of clean work places, floors, and equipment. Frequent mopping of soiled work places is necessary. The importance of adequate general ventilation and efficient local exhaust ventilation, where indicated, as preventive measures cannot be overstressed. The application of dope and lacquer-containing solvents always should be conducted under exhausted hoods. Protective clothing includes rubber gloves, aprons, and boots. Where rubber gloves are worn, they must be kept in good repair, as any fluid between the rubber and the skin aggravates the hazard. Men should wear washable work clothing or overalls which can be kept clean. Ample toilet and washing facilities should be provided, and men should be required to take showers and change to clean clothing before leaving the plant. Men handling lime, soda, chrome, and other irritant substances should wash their hands fre quently in running water, and clothing which has become saturated with solutions of these irritants or impregnated with dyes should be washed and dried before rewearing. The application of protective ointments, such as lanolin, castor oil, or a mixture of the two, may be effective in protecting exposed surfaces of the skin. Workers should be instructed in the proper care of the skin, and be examined at frequent intervals by the plant physician for early evidence of skin diseases in order that they may be promptly cared for. Workers exposed to ex tremes of temperatures and high humidities should be pro vided with suitable protective clothing, and every effort should be made to maintain temperate air conditions through adequate heating and ventilation. Shoe end Miscellaneous Luther Goods Persistent forms of occupational dermatitis, particularly among polishers and finishers, are not at all unusual among workers of this group. The materials, many of them irri tating, which are used in these processes, are so numerous that it is frequently difficult to determine the offending agent As is the case among tannery workers, the usual rite of the skin lesion appears first on parts of the body most ex posed to direct contact with the irritating substance, or on parts of the body covered with clothing which permits penetration by the material. Although the various solvents used in the processes are responsible for many instances of skin irritation among these workers, alkalies, such as ammonia, and oxalic acid, also, are irritating agents. Leather dusts, more noticeable in the naumkeging departments where sanding and dusting are conducted, are mildly irritant to the skin as well as to the respiratory mucous membranes. An occasional individ ual may become sensitized to leacher proteins and develop allergic reactions, such as skin affections and asthma. It is important that sanding and dusting be conducted under exhaust hoods large enough to be effective in exhausting the dusts. Despite the relatively little dyeing of leather which is carried out in shoemaking, it should be remembered that leather pressers have been known to contract dermatitis from the fumes given off when the hot iron comes in con tact with the leather. It is possible for the heat of the iron to decompose some of the dyes used on leather into their intermediates, or into other irritating compounds which are volatilized and are carried off in fumes. Blackening of heels and soles, as part of the finishing process, may give rise to skin irritation. Good housekeeping, adequate ventilation (local and gen eral), and protective clothing, discussed in the section on tanneries, are equally applicable to plants engaged in the making of shoes and miscellaneous leather goods. Toxic Substances Of interest from the point of view of this report, which is concerned with health hazards encountered in the indus try, is the variety of chemical agents encountered in plants during this survey. These include lacquers, naphtha, gaso line, acetone, ethyl ether, ammonia, methanol, benzol, amyl acetate, ethyl alcohol, ethyl acetate, butyl acetate, butyl alcohol, carbon disulfide, carbon tetrachloride, cellosolve, toluol, coal tar pitch, dyes, lead, and phosphoric add. The latter may release formaldehyde from the shoe. It is not to be inferred that all of these substances are used in every plant. In many instances only a few may be employed. Plants have been grouped in Table A (See Page S) accord ing to the type of goods manufactured, approximate number of employes with percentage of female workers, and a gen eral evaluation of housekeeping, personal facilities, and lighting. It is found that the industry engages a fairly high percentage of women workers, and, if this survey can be considered representative of the industry, that management generally appreciates the importance of good housekeeping, ample lighting, and the provision of personal facilities. The substances found in the tanneries studied and their concentrations in the air are shown in Table 1. (Page 7). The range of concentrations of solvent materials in the atmosphere at breathing level in shoe manufacturing plants is summarized in Table 2 (Page 9); the range of dust con centrations found in shoe factories in Table 3 (See Page 10). Detailed information of solvent vapor concentrations found in the air at the breathing level of workers engaged in various departments and operations in shoe manufacturing plants is available in table form, and copies may be procured by writing to the authors.4 Discussion Although the potential hazards of the leather industry as a whole are many, because of the variability of the processes and of the chemical agents employed, the health hazards in any one plant are comparatively few and can be controlled or greatly minimized without undue interference with the processes. ^Tables 4, I and 4, which are not printed here, are also on file at the American Documentation Institute. Offices of Science Service. .MOI Constitution Ave., Washington, D. C. Page I of Table 4 n printed on Page !1 it a (ample; the whole cable consisting of 1) pp- 6 i V8 Mint No. Operation ] Buffing operations 41 3 Leather duit Finishing dept, dusting hides 2 Titanox talc 4 - 7.2 Finishing dept, spray room Finishing dept, topping leather Finishing dept, sharing and buffing hides Finishing dept, hand finishing spray finishing Butyl alcohol, butyl acetate 160-300 1 Butyl alcohol, butyl acetate 2 Leather dust 2 - 5.3 126 12 Mixture of .............. 8 alcohols, ace- .............. tates, toluol 80-2*0 100--400 Finishing dept, hand dipping leather strip 4 Buffing, burnish- 1939 ing and sand 1940 ing hides 8 Petroleum naphtha 3 Leather dust 6 Leather dust Powdering machine 1939 1 Talc 1940 1 Talc Water purifying 1939 1 Calcium plant dumping lime Color mixing 1939 1 Basic black dye room 1940 1 Basic black dye Stuffing room 1939 2 Acrolein Beside pickling 1939 1 Sulphuric acid vats 1940 1 Sulphuric acid 1939 Hydrochloric acid S Pasc S for Continuation of Tabic I .............. 20-120 ... 8.1-12.0 ...................... ... 6.4-18.8 ...................... 14.6 7.8 ...................... ...................... .08 .03 .1 t .04 t t Remarks Product: upper leather; domestic cow hides Tanning materials: chrome, some vegetable re-tan Type tanning: drum tanning Colors and dyes: synthetic dyes Finishing: water spray finish 430 Product: upper leather; domestic hides Processes: lime bath, sodium sul fite added Tanning materials: chrome with a small amount vegetable re tan Type tanning: drum tanning Colors and dyes: synthetic dyes Finishing: lacquer -- hand and spray 200* Product: fancy leather and calf; foreign and domestic hides Processes: lime bath: arsenic sul fide added Tanning materials: vegetable-- ...... small amount chrome Colors and dyes: synthetic dyes used chiefly Finishing: lacquer -- hand and spray 880 Product: upper leather; 3700 hides a day; domestic cow hides Process; vat and drum tanning Tanning materials: chrome and vegetable Colors and dyes: vegetable and synthetic Finishing: lacquer and water spray a female, female. tNegatirc. 7 TABLE 1 Tanneries (Continued) ** 1t-5ih5 1 siilla Flint No. Operation AJ Ig Z3 E j3s J-ls's 31U 4 (Continued) 1940 Hydrochloric acid Preparing spew 1939 remover 1939 Compressor room 1939 Car unloading 1939 hide house storage room 2 Ether 2 Benzol J Ammonia fumes 12 Hydrogen cyanide Hydrogen beam house Finishing dept. 1939 hand finishing 1940 sulfide 24 Ammonia 29 Ammonia ' 1939 26 Alcohol, fusel oil, 1940 34 formaldehyde, celosolve, ace tates, acetone, etc. Spray finishing 1939 6 Ammonia 1940 6 Ammonia Chrome room be- 1940 1 Chromium side operator tNatiT*.________________________ J 23-30 100-120 23-30 t 23--400 20-430 20-100 20-120 t t t .038 The industry, through improved methods such as the "one-bath" tanning method -which eliminates the handling of hides saturated with chromic add, the substitution of machine spraying for hand spraying, and the increasing use of mechanized operations and labor-saving devices, has contributed greatly to the protection of its workers. Certain plant operations do permit the escape of volatile toxic materials into the environmental atmosphere, and in some instances, unsafe concentrations are reached, par ticularly during the heating season when windows and doors are dosed. Despite the tendency to substitute less toxic substances for toxic ones, such as the increasing use of petroleum naphtha as a solvent in a number of processes in place of the much more toxic benzol and its homologues, appreciable quantities of the latter, used either as such or in combination with other solvents, were found in the present survey. In the foregoing study a total of 38 plants was sur veyed and air analyses made at operations where potentially hazardous materials were handled. In 4 tanneries a total of 208 samples of the air were collected for dust counting and analysis for toxic substances and solvent vapors; in 22 shoe factories a total of over 383 air samples were col lected and analyzed; in 3 sole and heel plants a total of 22 air samples were collected and analyzed; and in 9 plants manufacturing miscellaneous leather goods, approximately 130 air samples were taken and analyzed for a variety of substances. In the tanneries (Table 1) among 94 samples analyzed for toxic solvent vapors, such as benzol, alcohol, acetates and mixtures of these used in finishing processes, only a few showed concentrations slightly exceeding the generally accepted safe limit for prolonged exposure. As a rule, spray finishing operations were protected with exhaust ventilation, but in handling the volatile solvents in other ways, such as the preparation of finishes, or their applica tion by hand, natural ventilation was usually relied upon to remove the fumes. Among the air samples analyzed for ammonia, acids, acrolein, dyes, hydrogen sulphide, hydrogen cyanide, chromates, and lime, ammonia was the only one found to exceed the safe limit with any fre quency. Chromic acid was present in excess of the per missible limit (0.1 mgm. per cubic meter) in the one operation sampled, but the operator was protected by a respirator, and the exposure was only intermittent in this case. Acrolein, hydrogen cyanide, and hydrogen sulphide could not be detected in the air in any of those processes in which they have been reported to be found. Dust counts made from 20 air samples taken at grinding, buffing, and powdering operations showed the highest count to be just under 20 million particles per cubic foot of air, while less than % of all the samples showed counts ex ceeding 10 million particles per cubic foot. Analysis of the dust showed that it consisted chiefly of leather, talc, or titanox. The dust-producing operations were in most cases provided with adequate local exhaust ventilation. The concentrations found of this mixture of materials could not be considered harmful on the basis of present knowledge. In the shoe factories among the 300 air samples col lected around cementing, spraying, finishing, and cleaning operations, where organic solvents were used, the concen trations of solvent vapors found in the air ranged between 8 TABLE 2 Solvent Concentrations at Similar. Typical Operations in Shoe Plants Number of operation! in vinous concentration ran|ce Operation 9a hC ii -1 i & Solrents used principally 8O, d o d d o <| C4Ok. eo B ead> 4 dQ i dd. Ae &i eod NoT ai oosd* id d ooe eo s Fitting dept. Cementing linings, assembling. 26 m Petroleum naphtha 1 10 8 X 312 etc. Underlaying perforations 7 22 Acetates 142 Stock fitting Insole stiffening 11 33 Alcohol 1 442 Cementing sock lining 4 7 Petroleum naphtha 1 2 1 Cementing soles for stitched shoe 8 20 Petroleum naphtha 14 21 Cementing soles for ce 7 24 Ether, acetone, alco 31 11 mented shoe hol, acetates Celluloid heel covering 7 4J Alcohol, ethyl ace 222 .... tate, acetone Leather heel covering 2 4 Petroleum naphtha .... 1 1 .... Lasting Cemented linings Box toe softening 3 8 Petroleum naphtha 1 2 .... 2 6 Acetates 11 .... .... .... Bottoming Cementing uppers stitched shoe Cementing uppers cemented shoe Applying softener 3 7 9 Cementing crepe soles 7 Cementing uppers for crepe soles i Laying crepe soles 4 Channel cementing 11 8 Petroleum naphtha 25 Ether, alcohol, ace tone, acetates 50 Ether, alcohol, ace tone, acetates Id Benzol 11 Benzol 12 Benzol 43 Petroleum naphtha .-. 1 13 21 111 .... .... I 12 12 I 13 I .... 11 5I 2 1 2 .... .... 13 .... 1 11 Finishing dept. Cleaning shoes 7 20 Acetone, ether, petro 4 2 1 leum naphtha Treeing shoes 9 2d Ether, petroleum. I 1 1 1 naphtha Spraying lacquer 8 19 Alcohol, acetates, 2 1 3 1 10-20% toluol 'Thai fifur* represents 6100 parts per million of methyl alcohol. This figure represent! J70 parti per million of benzol and toluol. 1 1** ia. io. O8. & 6 <5 i* l i zero and 200 ppm in the majority of instances. In a number of plants, however, the concentrations exceeded safe limits or even dangerous limits, and this was especially true of operations where benzol was encountered. Al though benzol was used as a solvent in only 7 of the 35 shoe plants studied, it was present in concentrations above the generally accepted permissible limit for prolonged ex posure of 100 ppm of air in the majority of the operations in which it was used, principally in that of applying crfpe soles (see TMe 2). In several other plants benzol was used in combination with other solvents. Toluol was generally used in mixtures, but may have been present in excessive concentrations in several operations. In one operation of celluloid heel covering where methyl alcohol was used, the vapors were found in dangerously high con centrations in the air. Acetone was found in excessively high concentrations in 2 samples taken at a bottom ce menting and a sole laying operation in the same plant. In grinding, buffing, cutting and powdering operations, the dust collected was found to be chiefly leather dust, mixed in some instances with rubber, talc, or chalk, and insignificant quantities of carborundum. Of the 73 air samples from which dust counts were made, only 7% showed counts ranging from 15 million to 20 million par ticles per cubic foot of air, while approximately 18% of the samples yielded counts of from 10 million to If million particles per cubic foot (see Table S, Page 10). Three sole and heel plants exhibited no important toxic hazard, while the operations at 11 miscellaneous leather goods plants were so varied that general conclusions cannot readily be summarized. The safe operation of processes in these plants falls within the special fields of safety, engineering, and medi cine. Safety measures, including training in safe methods of work, must be employed to prevent accidents. Where harmless substances cannot be substituted for harmful ones, labels on containers and drums should indicate the hazard ous nature of the substance and workmen should be in- 9 TABLE 3 Dust Concentrations at Similar Typical Operations in Shoe Plants JJ Operation 1 2. 8 5* 8. i o Z Cutting dept. Cutting uppers 2 33 Roughing up pers and lin ing J 9 Fitting dept. General air 2 100 Lasting dept. General air 2 Bottoming dept. Pounding and rasping up pers 8 16 Edge trim ming >13 5J Heel trim ming 8 19 Bottom sand ing 8 16 Finishing dept. Heel scouring 6 15 Naumkeging 5 12 Blowing off shoes 31 Stock fitting Sanding out- soles 6 13 Sanding wood heels 36 Channeling insoles 11 *3 >g>. H Leather Leather Misc. Misc. Leather Leather Leather Leather Leather Leather Leather Leather Wood Leather s -si 5o u a "J ti I! ME *-a85. 7o-!3 i= S il a e Z8 2 .... 14 2 .... 2 .... 42 94 6I 62 1S 22 11 41 3 .... 1 I *8 Zo 13 trueted as to dangers. Good housekeeping is essential and includes the care of spilled solutions and receptacles for soaked rags. Provision for showers, lockers, lunch rooms, and drinking facilities contributed to the maintenance of health in workers. Engineering control measures involve periodical deter mination of the concentration of harmful substances es caping into the plant atmosphere under operating condi tions, and the application of necessary corrective measures wherever they are indicated. Control measures include the segregation and complete enclosure of offending proc esses if at all practical, the employment of local exhaust ventilation and increased general ventilation, and other measures which the engineer may devise which will effec tively control the hazard. There is no single measure applicable to all operations. A combination of measures usually must be employed to insure success. The entrap ment by localized exhausts of harmful vapors and dusts at their sources of origin, and their disposal in such a manner at to prevent their dispersion is a practical method generally. Exhaust ducts, particularly those at tached to spray booths, should be extended to the roof and not discharged outside of windows where the fumes may reenter the building. Important also is the periodic checking of exhaust systems for defects in order to main tain effective operation. Good general ventilation, at all times, and adequate heating in cold weather should be provided. Workers employed in hot atmospheres, such as drying rooms, should allow their bodies to cool gradually and, if possible, should take a shower before leaving the plant, particularly in cold weather. They should drink plenty of water, preferably with a little salt added to replace the salt lost in sweat. It is advisable to isolate drying processes so as not to expose other workers unnecessarily. Protective clothing, bathing, and changing to dry cloches also are recommended measures for counteracting ill effects from dampness and variations of temperature. Medical supervision is an essentia] part of any health program. In the smaller plants, a trained nurse working under the direction of a part-time or consulting doctor is invaluable in caring for minor injuries, skin irritations, and emergency first aid work. Many infections and serious cases of occupational dermatoses and illnesses can be pre vented by the early application of remedial measures. The measures designed for the protection of workers against specified occupational diseases is discussed in more detail in the report. The doctor should familiarize himself wich the toxic effects of all harmful substances encountered in the plant under his supervision and with the special diag nostic methods for their detection. It is his responsibility to advise the plane management with respect to measures of personal protection to be applied to the workers. Summary A report is presented of a survey of the physical en vironment of the leather industry, consisting of a total of 52 plants, including tanneries, shoe, and miscellaneous leather goods factories. A brief description of processes employed in making leather goods is given, and health hazards, either real or potential, incident to manufacturing processes are discussed. It was found chat the industry itself, by the introduc tion of new and improved methods, has eliminated many of the hazards formerly associated with older methods. The chief hazards remaining lie in the common use of a wide variety of chemical substances, including alkalies, acids, chromates, vegetable and synthetic tanning materials, oils, finishes, dyes, solvents and other materials which may cause skin affections and systemic poisoning among workers either handling these materials or exposed to the vapors of those which are volatile. In a number of plants the con centrations of volatile vapors in the plant atmosphere ex ceeded safe limits or even dangerous limits. This was especially true where benzol was encountered. Skin infections following small abrasions and cuts are hazards particularly present in all tannery jobs. While the less dangerous pus-producing organisms usually are the causative agent the possibility of anthrax infection among workers handling hides must not be overlooked. Many tannery workers, also, are exposed to varying tem peratures and humidities, and to wetness, which may be in fluencing or contributing causes of illness. Practical measures for the safe operation of plant processes are outlined. 10 ft TABLE 4 (Part l) Shoe Manufacturing Plants Plant No. Department Opendon No. utopia Solvent* Type solvent Concentre* tion, p.pju. Remarks 5 Fitting Cementing 4 Petroleum naphtha Stock fitting Celluloid heel covering 1 Methyl Alcohol 440 6100 Bottoming Bottom cementing Sole laying 1 Acetone 1 Acetone 1320 2200 6 Fitting Cementing for doubling 1st table 4 Petroleum naphtha 2nd table 4 Petroleum naphtha extreme right of 1st 6 Petroleum naphtha table cementing through b Petroleum naphtha out rest of room Underlaying perfora 4 Butyl acetate tions Cementing linings 2 Petroleum naphtha JO--200 200--400 400-1000 20-80 20-50 20-60 Stock fitting Cementing soles Cementing soles 6 Ether, alcohol, ace tone, ethyl acetate 60-140 1 Petroleum naphtha 200 Celluloid heel covering J Alcohol, acetone 30--50 Bottoming Cementing leather heel covert Cementing uppers center of room side of room 3 Petroleum naphtha 4 Acetone, alcohol. ethyl acetate 4 Acetone alcohol. ethyl acetate 100-1 JO 3 JO--400 1 JO-200 80 8 Heel covers soaked in open pans and placed on cloth to dry. No exhaust. 4 4 Cement applied by automatic dispenser. No exhaust. 4 Cement applied by hand 4 brushing. No exhaust sys 1 tem. Natural ventilation good except at 1st and 2nd 1J tables, here a partition stops any cross ventilation. 4 Felt pads soaked in butyl ace tate used to moisten strips. 6 Cement applied by hand brushing. Ventilation good. Cement applied by machine. 2 No exhaust. 2 Cement applied by hand brushing. 8 Heel covers soaked in crocks. Drained on cloth. Ventila tion good. 2 Covert brushed with cement and allowed to dry in rack. 1 Machine cementing; concen tration decreases rapidly a 1 few feet from source. *Tsblcs 4, J sad 6, which arc hoc printed here, are also oa fils at the American Documentation Inatitect, Ofica of Science Service, 2101 Con stitution Avt., Vashingtoa, D. C. Psge l of Ttblt 4 is printed here ss t umpls; the whole tsble consiitinf of 1) pp.