INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASE
Abstracted by- E. R. HAYHURST, M.D., and N. C. DYSART, M.D.
Disposition of Dust in the Lungs.-(Ability of the White Blood Cells to Ingest Solid Particles).-A new quantitative method for measuring the ability of white blood cells to ingest solid particles (dust) is described. Particles of (a) carbon, or (b) quartz of uniform size were incubated with white cells. At frequent intervals a sample was removed to an ordinary blood counting chamber and the number of particles not taken up by the cells was counted. (a) Quartz. A method of calculating the chances of collision between the cells and quartz particles of different sizes is developed. It was found that large particles were taken up more rapidly than small ones because the chances of collision were more favorable. The speed with which three suspensions of different sized coarse particles should be ingested by the cells is predicted from the chances of collision, and the prediction is verified experimentally. By varying the speed of rotation of the tubes containing both cells and solid particles the formula for the chances of collision is also verified. (b) Carbon. In experiments with two suspensions of carbon particles the ratio of ingestion of the suspensions by the white cells are predicted by measurements of the diameter and rate of speed of the cells and of the particles. These predictions were verified experimentally. The results indicate that particles of carbon 4.7 microns in diameter are ingested as readily as those of 3.2 microns diameter. The more rapid aPParent rate of ingestion of the 4.7 micron particles is due to their greater availability rather than the greater capability of the white cells. In -the absence of serum or in heated serum there is almost no ingestion of carbon particles by the cells. Silicious dust (stone, sand, flint), when inhaled tends to remain in the lungs, causing phthisis, while coal dust, on the other hand, tends to move out of the lungs and is therefore harmless. The different behavior of silicious and carbonaceous dusts in the lungs is also the cause of the abnor158
mally high mortality among silicious miners and the abnormally low mortality among
coal miners. There is for some reason greater attraction between the cell substance and the carbon, than between the cell substance and the quartz. -The first step in the mechanism of dust removal from the lungs appears to be always the ingestion of the dust particles by the white blood cells in the air cells of the lungs. When both carbon and quartz particles are in suspension in serum, carbon particles are ingested about four times as readily as quartz particles by the white blood cells. This was verified by a new method described as the "film method" in which the cells ingest particles as they creep about on a microscope slide.-Wallace 0. Fenn, Jour. Gen. Physiol., May 20, 1921, Vol. III, No. 4, et seg.
Does the Magnetic Field Constitute an Industrial Hazard?-The conclusion is reached after experiments performed upon
various types of nervous and muscular tissues, upon blood and upon intact animals that the physiological effect of constant magnetic fields varying between 18,725 and 2,800 c.g.s. lines per square centimeter, is nil. The experiments utilized field strengths far greater than those to which workmen are subjected, and since the tissues employed were those most likely to show vulnerability, it seems certain that the magnetic field has no significance as a health hazard.-Drinker & Thompson, Jour. of Indus. Hygiene, August, 1921, Vol. III, No. 4, pp.
117-129.
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Miner's Nystagmus and Compensation.On May 22, 1907, miner's nystagmus was added to the schedule of compensable disease in Great Britain. Since that year the number of cases of nystagmus receiving compensation has been steadily increasing. The employer points out that the disease was little heard of until compensation could be obtained and the colliery manager says that the sequel to giving a man notice is the production of a surgeon's certificate of
INDUSTRIAL
disability for nystagmus. "War physiology has shown that many men placed in a position of danger or in uncongenial surroundings unwittingly react to their environment, and develop a neurosis of some form in order to escape. In the same manner the soldiers of industry who are unfit for or unsuited to their occupation develop a neurosis which brings them relief. If in addition to freedom from uncongenial work the release is associated with pecuniary advantages, the unconscious motive is doubly strong-one might even be tempted to say that it is quadrupled. It is quite common nowadays to hear colliers referring to the pit as the 'hole'-a word of sinister meaning, and a term which the writer does not remember hearing from a normal collier." However, due tribute of praise is given the majority of the underground workmen for dogged courage in their affliction. Many men hold on to breaking strain, and force their wills to overcome the many handicaps of the disease. The incapacity caused by the disease is largely due to the development of psycho-neurotic symptoms. The following measures for the prevention and limitation of incapacity are recommended: (a) A preliminary eye test before engagement. (b) Provision of surface work. (c) Right of periodic appeal to a medical referee. (d) The automatic and gradual limitation of the amount of compensation paid. (e) A restricted policy of lump sum settlements. (f) The expansion of the school medical service for vocational selection of boys suitable for work underground.-T. L. Llewellyn, Jour. of Indus. Hygiene, Vol. IV, No. 8,' December, 1922, p. 335.
Reducing Health Costs Through Health Supervision.-A demonstrable financial saving is the greatest single appeal for health supervision in connection with various forms of personal insurance as they appear in industry. The sound logic of improving health standards and the humanitarian element both contribute, but if it can be demonstrated that a plan of industrial heaith supervision will save money, a customer is secured. The main activities in a program of health supervision so conducted that the greatest influence is exercised in the reduction of costs in benefits, insurance, or compensation, as applied to disabled workers in
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industry, may be enumerated as follows: (1) Physical examinations of applicants and re-examination of those already employed. (2) Dispensary treatment of sickness, accidents, and, in many cases of dental, ocular, and other conditions. (3) Supervision of factory sanitation and the elimination of accident and disease hazards. (4) Absentee investigation, home nursing, and medical supervision in such cases as it may seem advisable. (5) Education in health, personal hygiene, and safety. (6) Facilities for the settlement of all claims involved in any benefits for sickness, accident, or death. Work along these lines led to the creation about two years ago, at the Hood Rubber Company of Watertown, Mass., of a mutual liability insurance company for the purpose of carrying their own liability in industrial accidents. All matters pertaining to industrial accident claims have been controlled and administered in compliance with state insurance regulation and compensation laws. As an adjunct to the medical service, a dental dispensary, an X-ray equipment and an ocular clinic was later established. The activities were gradually developed over a long period of time of different co-operating branches of medical supervision and claim settlement work, all directed toward the early detection, prevention, and reduction of disability due to disease and accident, and to show the background of the development of machinery for the settlement of all claims arising out of such disabilities. Thr.ee years ago a benefit plan was put into effect. This plan provides for the payment of benefits in cases of sickness, non-industrial acci, dent, and death, varying with length of employment from three months to five years and over, and ranging from $8.00 to $12.00 weekly, and covering a period of from seven to fifty-two weeks. Death benefits are also included. The company bears all expenses of this plan and entirely controls and administers the plan. Industrial accident disability was reduced from 0.85 days per employe in 1917 to 0.32 days per employe in 1921, and the percentage of employes disabled by industrial accident was reduced from 0.24 in 1917 to 0.10 in 1921. In this establishment about one-third of the workers are women. Except for accidents their rate of lost time is double that of men.
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Properly conducted health supervision, cooperating with adequate machinery for reduction of lost time and for the elimination of accident and health hazards and with those in charge of the settlement of claims, economically justifies itself.-R. S. Quinby, National Safety News, October, 1922, p. 31.
Plan of Industrial Clinics for Philadelphia. -It is not intended to discredit the efficiency and public good which the general hospitals are doing, but so far as they apply directly to industry they do not meet in all its ramifications the exacting modern industrial medical requirements. A plan is outlined which provides the industries of a city (Philadelphia) with a central clinic or industrial hospital with organized departments in the various specialties and these to be equipped with every means of diagnostic facilities, also branch or outlying clinics to be located in the industrial centers; each outlying clinic to serve the industries in that particular zone. The teaching of first-aid in all industries will be provided and first-aid workers will be relied upon to send the injured to the district clinic. In this system both industry and employer benefit. The immediate results in the improvement in the health of a body of workers are shown in the elimination of the employers' losses which come from such causes, which causes are obvious when we realize the vicious circle of cause and effect, and further, when we consider the effect of ill health on the quantity of production, on its relationship to ill-will and financial loss to the employer. The industrial clinic would develop a means of opening up a new field of research, comprising the effects of certain occupations on health, the frequency of morbidity and mortality from certain common diseases among certain groups of operatives and the effects of the general stress of industry, of speeding up, monotony, and general fatigue. A plan for a system of medical and surgical clinics for Philadelphia is outlined, under the headings: (1) Purposes; (2) Advantages (a) to the industries, (b) to the employes and (c) to the community as a whole; (3) Plan of Organization; (4) Location and Equipment; (5) Financing; and (6) Next Steps to be Taken. The delineation under each head is thoroughly discussed.M. R. Taylor, Proceed. of the Indus. Relat.
Conf., Dept. of Labor and Industry, Commonwealth of Pennsylvania, Vol. IV, Series of 1922, No. 2, p. 199.
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Industrial Dermatitis a Clinical Problem. -Dr. T. M. Legge states that industrial dermatitis is essentially a clinical problem. He classifies industrial dermatitis as due to: (1) definite chemical irrifants; (2) substances which dissolve the natural fat from the skin; (3) maceration; (4) mechanical injury. In his experience chronic ulceration is common, but he has yet to see a carcinoma developing from chrome lesions. The wash basin is not the cure or sole preventive of industrial dermatitis. Suitable greasy preparations should be supplied to make up for the fat lost to the skin, or protective powders might be used;-The Lancet (London), Vol. CCIII, No. 5167, Sept. 9, 1922,
p.
570.
Need for More Consultation With Doctors When Framing Legislation.-In a report recently issued by the National Industrial Conference Board, 10 East 39th Street,
New York City, the conclusion is reached that the introduction of the physician into the industrial organization, often made during periods of stress or to comply with legislative requirements, has produced many interesting and beneficial results. The physician's work in the organization has revealed to the employer many sources of economic waste and to the worker the unnecessary price he is paying for inattention to his health and the health of the family; while to the physician himself has been given a broader view of his social obligations and of the value of his services in creating and maintaining better living and working conditions among larger numbers of persons of a fairly uniform social standing. The effective administration of workmen's compensation laws depends in a large measure upon the work of the medical men and yet as Dr. Frank L. Rector, Secretary of the Conference Board of Physicians points out, Washington is the only state to give a physician membership in its Indusfrial Commission by legal enactment. Dr. W. B. Fisk of the International Harvester Co., emphasizes the need for more adequate medical representation in drafting as
INDUSTRIAI HYGIENE
well as administering the compensation laws. Dr. S. M. McCurdy of the Youngstown Sheet & Tube Company says that in consideration of hernia by compensation commissions the rights of employer and employe should always be kept in mind and conclusion should be based upon the best thought of the medical profession in order that the injured worker may be returned to society a useful and productive citizen. He discusses the accepted medical conception of the causation of hernia and states that from his experience as well as the experience of many other industrial physicians, it is seldom due to occupational causes, but instead is produced by the aggravation of a condition present in the majority of persons from birth. Dr. McCurdy states that hernia should be considered as an occupational disease rather than as an industrial accident and cured by surgical treatment rather than by the wearing of a truss or makeshift device. It is his opinion that a worker with hernia should not be denied employment, but after physical examination to determine his capacity for work should be placed at work for which he is suited and his work supervised by the plant physician. In this way many men now denied employment can be absorbed into industry where they can perform useful service. Dust and Ventilation in Metal Mines.Under the direction of G. S. Rice, chief mining engineer, the U. S. Bureau of Mines has for several years studied dust and ventilation in metal mines as affecting the health, safety, and efficiency of underground workers. In general, the work has been conducted along the line followed by South African investigators in connection with studies of miner's consumption, but a much wider range of conditions has been encountered in the metal mines of the United States; in addition to effects from dusts of various descriptions and degrees of harmfulness, the health, safety, and efficiency of our metal miners are, in places, seriously affected by heat, humidity, gases, and movement of air. The worst condition seems to be hot, humid, stagnant air which is impregnated with finely divided dust from quartz or other rock composed largely of free silica; here the workers are usually
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physically unable to work at more than onefourth to one-third capacity; high unit costs to the management result, and at the same time the worker, within a short period-frequently in less than five years-becomes practically incapacitated for work. Where comparatively cool but stagnant air is impregnated with finely divided dust, largely of free silica composition, the underground. man-especially if he is on a contract or is doing piece-work-works at maximum capacity and thus breathes a maximum quantity of dust. Free silica dust is considered the most dangerous to health, and other dusts are definitely known to have harmful effects; probably any finely divided, insoluble dustincluding that of coal-breathes in large quantities for continuous periods of time by underground workers, will ultimately result in bronchitis, miner's asthma, miner's consumption, or lead poisoning, or will predispose workers to pneumonia or tuberculosis. A number of questions yet to be solved are as follows: Why one dust is more harmful than another; why dust of a certain chemical or mineralogical composition is harmful in one mining locality and relatively harmless in another; the best practical measures to avoid the ill effects of harmful dusts; how best to cause air to circulate with maximum efficiency and minimum cost to places where metal miners work; the quantities of air necessary under varying conditions; the physiological effects due to various kinds of gases; the degrees of air vitiation; and ranges of temperature and humidity.-D. Harrington, U. S. Bureau of Mines, Reports of Investigations, Serial No. 2374, July, 1922, pp. 1-2.
Increased Production on the Three-Shift
System.-The 1920 factory inspection report for the United Kingdom says:-"Practically all the continuous industries are now
working on the three-shift system, and cases of increased output, substantially greater than the increase of staff, are mentioned in three South Wales works formerly run on the two-shift system."-Bulletin, Ohio Council on Women and Children in Industry, Toledo, April, 1922.
A Pocket Canister or Respirator for Engine Crews When Passing Through Rail-
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road 'runnels.-The development of a pocket respirator which will largely alleviate the discomfort to which engine crews are subjected from the presence of sulphurous locomotive smoke when passing through railroad tunnels is announced by the United States Bureau of Mines. The canisters, which fit conveniently into a coat pocket, are filled with an absorbent mixture of activated charcoal and soda-lime, and contain filters of Turkish toweling. These small smoke respirators have had the hearty approval of the men who have used them, and
of this universal mask has been developed for the use of city firemen. Details of experiments performed in connection with
this work are given in Technical Paper S92, by A. C. Fieldner, S. H. Katz and S. P. Kinney, U. S. Bureau of Mines, Washington, D. C.
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CONVENTIONS, CONFERENCES AND
MEETINGS
This calendar is published through the cooperation of the National Health Council, 370 Seventh Avenue, New York City. The Council will be glad to answer promptly any written or telegraphic inquiries regarding meeting dates in order to avoid conflicts. March 4-5, Association of American Medical Colleges, Ann Arbor, Mich. March 5-7, American Medical Associa-
retain their effectiveness for months, They may be cheaply made and are a great improvement over the sponge respirators and handkerchiefs and towels now used by engineers and firemen when passing through unventilated tunnels. Slow, heavy freights, tion, Chicago. going upgrade through long, unventilated March 5-7, Mid-Winter Conference on tunnels cause the most discomfort, espe- Health, A. M. A., Chicago. cially when two or more locomotives are April 2-5, National Congress of Mothers used; and when trains become stalled the and Parent-Teacher Assns., Louisville, Ky. crews are in danger of being overcome. CarAmerican Congress on Internal April bon monoxide from locomotive flue gas, Medicine, Philadelphia. augmented in its effect by the high temperaApril 11-14, Amierican Physical Education tures, is the probable cause of such cases. Assn., Springfield, Mass. The bureau has recently investigated the May 1-3, Association of American PhyArmy type of mask for the purpose of de- sicians, Atlantic City. termining whether or not that type could May 7-9, American Association of Engibe so modified as to be of service in work neers, Norfolk, Va. about smelters, blast furnaces, or similar May 21-23, American Gynecological Soindustrial operations, or possibly even about ciety, Hot Springs, Va. mines. This investigation has shown that May 21-25, American Water Works Assn., the Army type of masks, while affording Detroit, Mich. protection against all the gases met in warMay 31-June 2, American Pediatric Sofare, does not afford protection against all ciety, French Lick, Ind. gases met in industrial life. More espeJune 7-9, American Orthopaedic Associcially, it does not protect against carbon ation, Rochester, N. Y. monoxide, the gas hazard in coal mines, at June 7-9, American Dermatological Assn., gas producers, etc., nor against such comAnn. Arbor, Mich. mon industrial gases as illuminating gas, June 9, Eugenics Research Assn., Cold natural gas, ammonia, and the products of Spring Harbor, N. Y. combustion found in burning buildings. For June 15-18, American Assn. for the Feeble this reason, the bureau has sought to im- Minded, Detroit, Mich. press on the public the limitations of the June 18-23, National Tuberculosis Assn., Army gas mask, and at the same time, to Santa Barbara, Cal. develop special types of nasks suitable for difJune 19-22, -American Psychiatric Associferent industries or occupations, that will serve ation, Detroit, Mich. to protect the wearer from the gas hazards enJune 25-26, Medical Milk Commission, countered in a particular field of work. The San Francisco. bureau has also done work on the so-called June 25-29, American Medical Associa"Universal" mask that will serve to protect tion, San Francisco. the wearer against all of the gases in air June 26-28, American Assn. for Anesthetcommonly met with. A light-weight form ists, San 'rancisco.
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