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Occupational Medicine Be: WILLIAM A. SAWVEH, Chief I-illlnr Stale Street, ltoclirslcr J, New York A, J. LANZA. New York AimilM L. WATKINS, lloslon WILLAIU) MACIIU:. New York wiM-ni:t) ovi-:mioLst-:it, waviiinmnn. i>. c. CLAItl'.NU; ]). S i; L11Y, I >rh o j | HKXlOltn L. I)IYI:LI:Y. Knns:i> Mo. / Von'ME 2 1946 14907 rrm.isiiERs AMERICAN MKDICAI. ASSOCIATION CHICAGO, II.!.. -C, H_ fii K;', %I f- '.firi- CONTENTS OF VOLUME 2 JULY 1946. NUM11F.R 1 .I'Af.i' 11 call 11 I'roKi'lifit in the Production and Use of Atomic Energy William h. Hale. l'U. 1 >., Koclicstcr, N. Y....................................................................................... 1 Anthrax' Its Diagnosis and Treatment. Henry Field Smyth, M.D., Dr.P.H., Porasset, Mass..................................................................................................................... 5 l'ernardino Ramazzini: His Life, Deeds and P.noW^- Robert T. Leggc, M.D., Herkcley, Calif........................................................................................................................ 22 Importance of Researches on War Gases to Clinical Medicine. Warfield T. Longcopc, M.D., Baltimore............................................................................................... 54 Surgery in Industry. Harry E. Mock, M.D., Chicago..................... ..................... 45 A Disease Resulting from the Use of Pneumatic Tools. Frederick M. Peters, M.D.. Chicago...................................................................................................................... 55 Practical Benefits of Industrial Health Service. Victor G. Uoiser. M l)., New York................................................................................................................................ 67 Abstracts from Current Literature...................................................................................... 7n Honk Reviews.............................................................................................................................. 92 AUGUST 194n. X U M11FR 2 What Industiy l-.xpeets of Medicine. Hemanl Strong, Washington. D. C. .. 94 Noxious Vapors in Aircraft Cabins. Lieutenant Colonel Harold Spent, Medical Corps. Army of the United States.............................................................. 161 Personality Components in employment Problems. F.ric Kent Clarke, M.D.. and Stanley G, Law, M.D., Minneapolis.................................................................. 116 Controlled Nuclear Energy: Its Attendant Hazards ami Benefits. Andrew H. Dowdy, M.D., Rochester, N. Y........................................................................... 126 Atomic Disintegration. Joseph W.Kennedy, St. Louis............................................. 1.-2 News and Comment................................................................................................................... 13S Fditorial : The Coal Mining Agreement......................................................................................... 144 Abstracts from Current Literature........................................................................................ 146 SEPTEMBER 1946 NUMBER 4 Psvchoneurosis and Industry. Walter F. Sciiallcr. M.D., Sati Francisco........... 154 ignifirance of Industrial Cancer in the Problem of Cancer. W. C. Ilueper. M I)., New York................................................................................................................. 190 Rehabilitation of the Sick and Injured. Rex L. Divclov, M.D., Kansas Citv, Mo.........................................................................................................................................'. 201 Tuberculosis Control in Industry: Results from 1041 to 1045. Charles R. Allison, M.l).. Rochester. N. 6................................................................................. 207 SIGNIFICANCE OF INDUSTRIAL CANCER IN THE PROBLEM OF CANCER W.C. HUEPER, M.D. NEW YORK THE study of occupational- eancer is of eminent significance tor the control of human cancer in general. As occupational cancers result from exposure to certain more or less well defined exogenous agents, they represent chance experiments on cancer in man conducted by modern industry on a large scale and thus are human equivalents of experimental cancers in animals.*1 In view of the known differences existing in the susceptibility and reactivity of various species to the numerous recognized physical and chemical canccrigcnic agents, indus trial cancers possess the great advantage over experimental cancers in animals that they permit (he direct stud)- of many of the most important and fundamental aspects of eancer in the human organism, such as the action mechanism of the different physical and chemical carcinogens, the character of the local and systemic reactions associated with the process of canccrization (shifts in the mineral, lipid and vitamin con tents of the cells acted on, qualitative and quantitative disturbances in the cnzvmc and vitamin activity, endocrine function, steroid metab olism, chcmoimmunity reactions and metabolization and detoxication of the carcinogenic agents), influence of age, sex and race, hereditary fac tors, diet, role of periods of exposure and latency and of procanccrous and anticancerons mechanisms and the factors responsible for multiplicity of cancers and systemic eancerization. It is obvious from these considerations that a thorough, extensive and continued investigation of occupational cancers through a study of man exposed to known occupational canccrigcnic agents or affected by industrial cancer would he of utmost benefit for a better understanding of the conditions which mnv cause cancer in man and of the measures which may prevent such developments. There is a second important reason calling for an appreciably increased interest in the problem of occupational cancer in connection From the Warner Institute for Therapeutic Research. 1. Ilticpcr, W. C. : Occupational Tumors ami Allied Diseases, Spriucficld, Ilf. Charles C Thomas, Publisher, 1942: tamer in Its Relation to Occupation and environment, Hull. Am Soc. Control Cancer 25:9, 1<I43; Industrial Manaccmct .ami Occupational Canrcr, J. A. M. A. 131:738 (June 29) 194d. IN THE gnificance for the nal cancers result exogenous agents, nail conducted by lan equivalents of known differences ms species to the nic agents, indusImental cancers in he most important mism, such as the nucal carcinogens, isociated with the i and vitamin con ative disturbances ai, steroid metabaid detoxication of ce, hereditary faci procancerous and . for multiplicity borough, extensive through a study amts or affected by < iter understanding nd of the measures for an appreciably ancer in connection -i-a'cs, Spriucficlil, Ilk, ,11 to Occupation ami b'biotriat Management 194fj. nunrnK--i\iwstiUal c.-h\lcnn 191 Hath the general problem of cancer. The rapid and enormous growth of modern industry and its vast diversification during the last five decades has been accompanied by a considerable rise in the absolute number and by the appearance of many new types of industrial cancers. This development reflects an important biologic maladjustment of civilized man to his new artificial industrial environment and represents a striking illustration of the momentous role which exogenous environmental agents apparently play in the causation of cancer in general. Experimental and clinical evidence obtained during the last few years makes it likely that new industrial carcinogenic, agents and heretofore unknown types of occupational cancers will be discovered in the next few years in American industries. This development is foreshadowed by recent observations indicating that certain types of industrial cancers which in the past were observed exclusively in European plants have made their appearance in American factories. Moreover, American investigators produced cancer in animals during the last few years by the exposure to carbon tetrachloride, ethyl carbamate, dictlivlene glycol, beryllium and ergot, i. e., substances extensively used in industry and/or for medicinal purposes. It seems to be fair to compare present knowledge as to the causation of cancer in man with that available on tiie causation of infectious dis ease during' the days of Pasteur and Koch. There exist good reasons for assuming that the majority of occupational carcinogenic agents are still unknown and that this applies especially to those occupational carcinogens which have a low potency and which therefore produce a low incidence of cancer not appreciably differing from that seen for the various types of cryptogenetic cancers among the general population. When these facts and their implications are properly and fully appreciated, occupational cancers arc hound to become n public health problem of the first order, which deserves to he seriously and exten sively investigated. I. OCCUr.V! IONAL CANCKR AND CANCUR RI.SKARCII A. Carcinogenic Agents.-- Tt may lie appropriate to recall here that modern cancer research dealing with physical and chemical carcinogens started some thirtv vears ago as an outgrowth uf the study of the causa tive agents and conditions involved in the production of occupational cancers. Although great strides in knowledge of exogenous carcino genic agents and their effects on the animal organism have been made since that time, the constantly growing number and diversity of types of occupational carcinogenic agents have raised many new and often I still unsolved problems. The existence of wide differences in the physi cal and chemical properties of the various established or suspected car- i ) ' i 192 on ui'.-moN.ii. fUiinaxJi rinogcns suggests that these agents do not exert their spccilic pathogenic action through the same mechanism. From an analysis of the data at present available on this matter and from theoretic considerations it appears that exogenous carcinogenic factors may elicit malignant growths through one of the following three mechanisms. In the first group those occupational carcinogens may he found which apparently cause a cancerous cellular transformation by acting directly cither in their original form or as metabolites or conjugates on the cellular substrate. The carcinogenic substances contained in tar. t pitch, asphalt, soot, mineral oil and related substances, and those repre sented by certain aromatic amines (belanaphthylamine, benzidine, ani line) perhaps belong to this group of primary carcinogens. The second group of exogenous carcinogens consists of agents which do not possess auv direct carcinogenic properties but which exert such action by changing some normal chemical constituent of the cells or tissue fluids in such a wav that, it becomes endowed with carcino i u genic properties. In view of the long latency period of actinic cancers, i excluding the possibility of a direct electronic chromosomal mutation, ii i seems probable that this mechanism may he active in the development of cancers caused bv radiating energy. An indirect or secondary mechanism of canceri/.ation may also he responsible for the occupational cancers observed in workers employed in chromate plants, nickel refineries, asbestos factories and arsenic operations. In a third group those exogenous agents are included which have neither primary nor secondary blastogcnic properties, hut which elicit functional disturbances in certain organs, such as the liver, adrenal glands, pituitary gland and the gonads. The quantitative and or qualitative functional abnormalities thus produced may lead in turn to the development of endogenous substances or metabolites possessing carcinogenic qualities. The possibility of such a mechanism has not hern extensively explored and is mainly speculative, hut certain aromatic t } azodyes may belong to this group of exogenous carcinogens. It is obvious that adequate information on the sources and types of carcinogenesis not only is essential for determining the scope and effect ! ing the control of environmental cancer and, especially, its occupational variety, hut also may bring about a closer connection between the carcino t genesis bv the action of exogenous substances with that apparently ensuing from endogenous factors. /'. Srx.--The observations made in occupational cancer in man and its ex[x;rimental equivalents in animals show- unmistakably that am differences in the sex distribution of such timinn are not vex conditioned hut are the results of variations in exposure. The great predominance of t '*****>. oogenic lata at ions it growths found acting ;atcs on in tar, reprene. ani- agcnts h exert lie cells arcino.'.uicers, iiion, it ilent of hanisin .incers fineries. h have eh elicit adrenal and/or turn to messing has not aromatic Hpes of I cffecti jiational carcinoparently man and i hat any iditioncd nance of l 3 H VhPER--IXPL'STKI. 7. c .-l.\CUK i ];.t males among persons affected by occupational cancers is mainly jitirihutable to the fact that industry lias employed, until relatively recently, men almost exclusively in such hazardous op< rations. Onlv during periods of abnormal strain in the available manpow er have women been used on a larger scale in operations involving exposure to carcinogenic agents, sucli as aromatic amines, tar, pitch, mineral oil. and related substances. The temporary nature of such an employment in addition to the lack of subsequent medical supervision of these women mainly accounts for the fact that in most instances of occupational cancer little information is available as to the incidence and occurrence of such neoplasms in the female sex. Wherever, on the other hand, occupational carcinogenic agents acted on members of both sexes cancers appeared in both, males and females, according to their relative number exposed and to the degree of exposure sustained. Thus cancer of the skin due to roentgen rays has been seen in men and women. Inversely, operations with carcinogenic hazards in which mainly female workers were present exhibited a prevalence <>f occupational cancer among women. The occurrence of cancers of the lone among girls working in luminous dial plants exemplified this relation. These observations on the sex distribution of occupational cancers suggest that environmental factors may plav an important role in the causation of the numerous cryptogcnetic cancers affecting certain organs (lungs, larynx, gastrointestinal tract and skin) which have extensive contact with exogenous agents, because these cancers occur much more frequently in males than ill females. C. Age ami Life Span.--The claim has been re]>eatedly advanced that an age factor represented by the relative age or the average life span of a particular species has a significant part in determining the degree of susceptibility to carcinogenic agents and the relative speed of tissue cancerization as expressed by the latent period. Clinical and experi mental evidence obtained on exogenous occupational and experimental cancers, however, does not lend support to this contention. It is the age at onset together with duration and intensity of exposure which controls the manifestation age of occupational cancers. Depending on these fac tors industrial cancers have been observed in persons between the ages of 10 and 80 years. the biologic dynamic*. some support when man and mouse, it species and different tvoes of exogenous cancers, S' W --t .9 * wrv ,. ' * rS' . C' T2.** '. z'%': i'' 1i ' ( i I j I 194 OCi. ' /'. I / /(').Y.I/. Ml'niCIMi Ultraviolet ray cancel uf the skin, for instance*. can he elicited with out difficulties in mice and in rats, bin not in rabbits; cutaneous cancer develops readily in mice after the application of a hcnzolic solution of mcthylcholnnthrcne, but not in rats ; the skin of rats and monkevs does not respond with any appreciable speed or permanence to 1 he carcino genic action of tar, although the skin of mice rearts rapidly, consistently and persistently to this agent with the development of cancer. Tims, regardless of the relative length of their average life spans, certain species .are either completely refractory or ahnormallv resistant to carcinogenic agents which elicit easily in mice carcifuigcnic responses under equal conditions of exposure. ' Observations on occupational cancers in man show, moreover, that in some persons only comparatively short exposure time (six to twelve months) arc necessary for eliciting the development of aniline cancers of the bladder or chromate cancer of the lungs. If the aforementioned dogma of the biologic dynamics of cancer genesis in relation to speed of senescence is applied to such cases one is forced to assume that some men apparently possess organs which age in an extraordinarily short time, while others with exposure times of twenty to thirty years undergo senescent changes in slow motion. Inasmuch as it has been established that different species metabolize carcinogenic agents by different methods into difl'eient metabolites, it appears to he more plausible that the observed discrepancies in tiic speed of tissue cancerization in various species arc related to their dif ferent special metabolic activities and not to their senescent dynamics as expressed in average spans of life. It may l>e noted in this connection that the observation of spccics- sjx'cific differences in the susceptibility to various physical and chemical carcinogens may make it necessary to qualify in the future the term "carcinogen" by adding the species which reacts or react with the development of cancer to a certain "carcinogenic" agent. The importance of this consideration for the testing of occupational carcinogens in ani mals is obvious. j I ! i D. Heredity.--Although it is possible that hereditary factors may i determine in part the length of the period of latency and of the time of : exposure necessary for eliciting an occupational cancer in the individual j case, there is no concrete evidence that a genetic predisposition plat's I any important role in the incidence of these tumors. The intensity and * t\pe of exposure and the potency, of tin- carcinogenic agent involved . J appear to he the main factors in this respect. Whenever these conditions j are favorable to the development of a cancer, there is found an carlv j occurrence, a high incidence and a marked multiplicitv of occupational ) cancers. Thus, aniline cancers (if the Madder appear in 30 to 0t) per J .J, cent aw1 sam and win run; piv pm dm Scl. If ; sin Oil' piw Six or ; tin:. the ain; bet1, tin: the act cal: can t hi re;-' Wh' mr pn lor raa the H ra' Im pel in i ' '. ithmccr 'll of docs inoently 'Inis, I iccies genic . qual . that welve mcers ; i nited ed of >nmc diort 'k--rgo hnlize dies, it n the iv difamics lecics- .emical c term th the nrtance in ani- is may lime of hvidnal n plays ity and nvolved nditions 11. early i ritional ')() per liUiirnK-ixnvsrKi.-u c.i\au< 1V5 cent of the massively exposed workers. Cancer of the lungs kills SO pol ecat of the Schneeherg miners and between 40 and 50 per cent of the Joachimsthal miners exposed to radioactive material. Cancer of the same organ, on the other hand, is found in only 4 per cent of the dead and living chromate workers and in 12 per cent of the asbestos workers who came to autopsy. Attempts have been made to attribute the high incidence of pul monary cancer among the Schneeherg miners to a familial hereditary predisposition prevalent among the population of this region. This purely speculative concept lias no factual basis and ' apparently was developed without any reliable knowledge of the actual conditions in Schneeherg concerning the incidence of marriages among close relatives. If an analogy with the genetic background of certain mouse strains showing a comparable incidence of mammary cancer is permissible, one would have to assume that the people of Schneeherg must have propagated by incest for the last three hundred to five hundred years. Such a proposition, however, is obviously outside the realm of science or good sense. E. Procnncatius am! .'liiticanct'rous Mrclianisms. --Recent observa tions made on occupational and experimental cancers have demonstrated the existence of faclors'which may enhance or impede the development and growth of cancers. However, a sharp distinction must he made between those agents which act in conjunction with a carcinogen and thus during the process of canccrization and those which influence the growth activities of an established cancer for which the continued action of a carcinogen is unessential. The last-mentioned factors are called procarcinotic when they favor the proliferation and spread of cancer cells and anticarcinotic when they have an antagonistic effect in this respect. Factors of the first group are cocarcinogens when they represent an integral part of a carcinogenic complex, procarcinogcns when they aid in the initiation of the transformation of normal into malignant cells and anticarcinogens when they interfere with this process. A constitutional anticarcinogenic factor is, for instance, responsible for the much higher resistance of the skin of members of the colored races to the carcinogenic action of solar rays than that seen in members of the white race and. particularly, those with light complexion, blue or gray eyes and blond or red hair. Similarly, colored persons are much less susceptible to carcinogenic tar, pitch and mineral oil than are white persons. It is like'}- that the higher degree of pigmentation of the skin in the colored races and the greater natural oiliness of the skin of Negroes account (nr ijicsv differences. - -* * 'J'j'*H'<**)**f Scrt : "/pi1-.. *- ^ J:*? . * U ' **.' M ' * <5^** '. JV***-.*- * *'* . WJ : -t #** < * - ` i. **' 5- '"tTd-L ."tS* - * . * '. V - z.%: ' y<; - 4 . ' '*v"' , ` -*y 1. i l` ` " " l ------i' , '--- - ..................................................... ..................... .. " ./ j% (H i. rr.iTioN.-ir mu>iu\i:. The assertion was recently made that purumoiioconiosis acts as a cocarcinogcn to other factors, such as radiating energy or arsenic, in 1 tlie development of cancel of the lungs in Schncchcrg miners. Inasmuch as nonspecific pncunionoconiosis does not exhibit any demonstrable causal relation tea cancer of the litn^s and is not essential to pulmonary action of other carcinogens (chromates, nickel carbonyl, tar and arsenic) the alleged cocarcinogcnic role of pncunionoconiosis in the cancer of the Schncelrcrg miners appears to lie highly uncertain. It is interesting to note that the role of all these factors is evidently not a fixed one. hut varies with the circtfnTstrtnces. For instance, hyper keratosis may play in rats a procarcinogcnic part in the initiation of cutaneous cancer caused by methylcholanthrene, while it assumes an nnticarcinogcnic role in the development of cancer of the skin caused by ultraviolet rays. Roentgen rays, rays from radioactive substances and benzene and arsenic arc well established carcinogens when acting in small doses over long periods of time, while they arc powerful anti- cnrcinotic agents when employed therapeutically in large doses given within a relatively short period. /'. Multif'licily <>j Cancers. -A multucnliic development of cancel is frequent with occupational carcinogenesis. While primary multiplicity of cryptogenetio cancers has been recorded in 0.5 to 5 per cent, this phenomenon has been observed in 15 to 50 per-rent of industrial car cinomas (arsenic cancer of the skin. 15 per cent : lar cancer of the skin. 20 per cent; paraffin and oil cancer of the skin, 15 per cent; aniline cancer of the bladder, 25 per cent; roentgen cancer of the skin, 50 per cent). Systemic multiplicity of occupational cancers has been noted in several cases of aniline cancer, in which the bladder and/or the ureters and kidneys were the sites of primary cancers. Hx]>osure to aromatic amines, arsenic, tar and paraffin oil and radioactive substances lias been associated in a few instances with hetero-organic multiplicity of cancers, afTccting simultaneously or successively organs of different systems, such as the skin, the lungs, the stomach, the bladder, and the kidnevs The excessive frequency of primary multiplicity of occupational cancers is evidently an expression of a relatively powerful carcinogenic stimula tion. The occurrence of hetero-organic multiplicity is of particular interest, as it throws some light on the so-called tissue specificity of certain exogenous carcinogenic agents. It seems to he a general principle that cancerous growths ensue most readily at those sites where the carcino genic agent is present in an optimal concentration and for the most prolonged period. The site, intensity and length of cx]>osure, the sjx'cd of absorption of the carcinogenic agent from the site of primary contact and the organs of deposition, of metabolic conversion and of excretion. t ! if i.i of nit ot tr; (< r1 an in A dr u< c n l!' ti ll FY- a P li. tlii .Li.L-1--- riH fin '^ -ji-- "V *i i> as a ' nic, in istmich istrable monary ivscnic) nccr of identic hvperition of uncs an used by ecs and ting in ul anti - given t cancer hiplicity nt. this ini carihe skin. aniline . 30 per noted in ureters aromatic is been cancers, systems, kidneys, i cancers stiinula- mtercst. ' certain iple that carcinoihe most hr speed, contact \crction. HVEPEK-IXl.H'STNi. U. C.I.XCliK V)7 in addition to the character of tin.1 metabolites formed. represent the factors which determine mainly the location of the carcinogenic responses to a given carcinogenic agent. These selected illustrations of the in >re important .scientific aspects of occupational cancers may suffice in demonstrating the eminent sig nificance which these tumors have in connection with the general problem of cancer. It. OCCUPATIONAL CANCERS AS A ITIIMC HEALTH I'ROHLEM It is only in rather recent rears that industry and puMic-and indus trial health organizations have become aware, in this country, that occupational cancers represent a public health and an industrial medical problem deserving serious attention. 1\ HolTmaii complacently noted about this matter in 1028 that the scarcity of recorded industrial cancers in the United States was attributable to the fact that the workers in America arc unusually intelligent and susceptible to educational inllucnre, desire to know the truth and facts of a given situation and frequently govern their eonduel accordingly. Hoffman added that this observation applied to no particular class of workers more than t> tlm>e who were connected with the chemical industries in which occupational cancers were unusually frequent in other countries. i. .. A look nt the record brings out the following facts: Althoncli the Untied States has been for several decades the leading industrialized country and has recently accentuated this position through the dcvelnp- ments and the outcome of the last war. it is obvious that this country does not equally excel in regard to the study, control, preven tion and legislative measures of industrial health hazards, especially those causing occupational cancers. liy the end of l`j45 only thirty-two states had passed some form of compensation law covering occupational diseases. Since the majority of such laws either contain time limita tion clauses as to the filing of compensation claims or apply only to a limited and well defined number of hazardous agents or operations, they provide inadequate or -defective coverage against the hazards of industrial cancer. This situation deserves serious consideration, as the enormous and rapid expansion of the industrial activities engendered during the war was not infrequently carried on under unfavorable conditions, such as inexperienced management and workers, emergency construction of plants and use of hazardous substances under the pressure of war without the possibility of instituting proper precautions. It stands to reason that the chances of exposure to occupational carcinogens faeed 1>v the industrially employed population of this country were increased hv these circumstances during the last few years. The results of such ;!*r. r 'Jtr '-a VS* -~C ;'v~ r *-r o:-; & WS- ; . #;V- .r. y 'K 5..-, -1 t- - l'JX oicer.nmx.iL mudicixh exposures in the lorni of cancers, however, will not heenmc manifest before ten to thirty years hence in the majority of persons thus exposed, that is, at a time when many workers have taken up employment of very different types and most of the women workers have abandoned their industrial activities and either returned to or taken up housework. It is obvious that the industrial origin of many of the then occurring occupa tional cancers will not be correctly recognized, and this will be particu larly true in regard to occupational cancers developing in former industrial employees of the female sex, unless the knowledge concerning and the interest in the occupational genesis of cancer become consider ably more widespread among the members of the medical profession tli is the case at the present time. . As industrial cancers are not notifiable diseases in most of the states and ns American industries have shown so far great reluctance in placing their eases of occupational cancer oil record, there exist in this country only incomplete data as to tire actual number and variety of these dis ease conditions, their causes and the audits and operations responsible for their development. This evident lack of proper appreciation of the importance of industrial cancer in the United States stands in sharp contrast to the unrestricted and wide publicity which these tumors have received for many years in other industrialized countries, such as England, Germany and Switzerland, in which industrial cancers are compcnsaoie and notifiable industrial diseases and from which for this reason rela tively reliable and complete official information concerning them is available. '' In view of the continued ignorance concerning the causation of the great majority of cancers occurring among the population in general it is regrettable that no competent and extensive investigations exist in regard to the possible role which industrial or related exogenous agents might play in the causation of some ol these tumors, the demonstration of such a relationship, if it exists at all, will not lie an easy task, as it is likely that any carcinogenic substances which might he inadvertently contained in the numerous articles of daily use possess a potency of rela tively low order. There is. moreover, no good reason to assume that such agents arc numerous and enjoy a wide distribution, as the majority of the definitely identified chemical carcinogens are rather specific, representing usually only a few compounds among a large group of noncarcinogcnic related derivatives The first step for an effective future control of the hazards of indus trial cancer in this country should be a comprehensive and thorough survey of all industries producing or handling known or suspected car cinogenic agents, including those occurring in the form of contaminants, by-products or waste products. Wherever eases of definite or suspected - .lest ''('(1, ' cry ilieir . It >ipa' ticunner ming ideri than states lacing untry c disusible "11 of -harp I lave land, ! ^nble i rclain is ' tlic aal it -t in ..gents : ation - it is tently . relac that i inrity I 'ccific, >t non- mdus.rnugh I carmants, pected I iiui:rni<-ixnr\n<i.!L < ,/.v< /;a- i')') industrial cancer arc i'Uitid the following data should he obtained: type of operation; character of carcinogen:.: agent or agents; absolute and relative number of workers a Heeled; sties, types, length and inten sity of present and previous exposures l" carcinogenic agents; local and general prccancerous symptoms and reactions; latency period; organ or organs involved ; incidence of multiplicity and histologic types of cancers; age, constitution, sex and race of persons affected: diagnostic, preventive, prophylactic and therapeutic measures taken and sociologic, sanitary and technical aspects (physical, chemical, engineering). I If occupational cancers should be found among the workers of a certain operation in one plant and should be absent apparently among those of a similar operation somewhere else, efforts should be made to ascertain any underlying differences (type and intensity of exposure; sex, race and rate of turnover of labor; details of manufacturing proc esses; type of precautionary measures; length of time operations were established; raw products used; intermediary and by-products gencr- , ated; climate, and diet). - Special attention should be paid in this connection to those American industries which have apparently remained free or almost free from occupational cancers, although numerous cases have heen reported from similar establishments in other countries (pulmonary and nasal can cers in nickel refinery workers and pulmonary cancers in chromate workers, asbo-^^x^H^^, ard arsenic workers). A thorough restudy of the potential cancer hazard to manufacturers .and handlers of arsenicals seems to be especially indicated, as recent observations made by clinicians in this country atld in Europe as well as governmental data from England show that not only an alimentary and therefore mainly habitual and medicinal exposure to arscnicals, but also a respiratory and cutaneous contact, which is prevalent in industry, mar cause the drxelopment of cancers of the skin and the interna! organs (lungs, alimentary tract). It is not probable that any occupational cancers of the skin or lungs and leukemias would he found at this time among the many persons who came in contact during recent rears with radioactive gases and =--^^_dust, because a much longer latency period is required in general before such complications become manifest. However, all persons who have sustained such exposures should remain under close medical super vision for the next twenty or thirty years. There can be no doubt that an evaluation of the data obtained in such a survey will permit conclusions which can be translated into definite research problems of an experimental or clinical nature and into useful recommendations for medical, sanitary, technical and legal measures. An effective control of occupational cancers requires the close and harmonious cooperation of many and diverse parties (physicians, chein- <*** . i-tr /v- .wr'fWt*- \ > f r' / 'IX) OCCUPATIONAL MILDICIMi ists, physicists, engineers, biologists, public health officials, law making and enforcing agencies and industrial management), if such collabora tion can be obtained, the great majority of industrial cancers known today may disappear within the next twenty to thirty years from the list of industrial diseases. The continued occurrence of occupational cancers, on the other hand, represents a challenge not only to the intelligence but also to the social conscience of human society, because industrial cancers may be compared with a biologic bomb having a delayed time fuse which may he placed in the body of the victim with out his knowledge and realization and winch may display its deadly effect many years later when the conditions connected with its intro duction arc often forgotten. f