« AnteriorContinuar »
lower point than copper, the other leading constituent, it is given off freely whenever brass is made or superheated after having been made. Also, it is given off very freely when the ores containing zinc are smelted. Inhaling these fumes is liable to cause a peculiar affection known as brass founders' ague. This, Dr. Hayhurst found, was very common among workers in brass foundries, zinc smelters, and other foundries in which zinc and zinc alloys are poured. This disease is practically never found in foundries with good ventilation, either natural or artificial. It is not regarded as serious by the workmen themselves, who rarely consult a doctor for it, but continued exposure to the conditions producing it tends to establish chronic diseases affecting the lungs, digestive tract, nervous system, and kidneys, so that occupational ill health is common. Of 187 workmen questioned, 146 complained of trade sickness or disease. In view of the recent discussions of the toxic effects of fatigue it is interesting to find the workmen themselves assigning overwork as a cause of occupational disease. “Workmen complain that they are now required to do from one-half to double again as much as they were wont to do 10 to 20 years ago.''
In the polishing, plating, and buffing processes the risks from metallic dusts and acid fumes are those found wherever such processes are carried on, and can be minimized or wholly done away with by the use of hoods and exhausts. There was considerable variation in the degree to which these devices were used. Of 30 plating firms visited, 27 had processes involving the use of large tanks of potassium cyanide solutions, and only 3 had any devices for removing the fumes rising from these.
In the zinc smelters the employees, about 2,000 in number, were almost exclusively Polish; no women and only a small per cent of boys and youths were employed. In the foundries and brassworking shops, a considerable proportion of English-speaking workmen were found. Women were employed to a limited extent in the foundries as coremakers, and in the brass-working shops mainly in the lacquering rooms and at polishing and buffing.
The study as a whole shows considerable risk to health in the industries considered, due in part to the nature of the materials used, but more to imperfect ventilation and other unhygienic conditions which might easily be remedied.
Owing not only to the enormous amounts of gas produced in the steel industry, but also to the large numbers of men engaged in it, the investigation into carbon monoxide poisoning was practically confined to the five large steel plants in South Chicago and Joliet. The peculiar intoxication produced by exposure to this gas in sufficient quantities is well known; the chief concern of the investigatorsDrs. Matthew Karasek and George L. Apfelbach, under the direction of Dr. Walter S. Haines--was to determine the effect of frequent or constant exposure to smaller amounts of the gas. In this respect the results obtained were inconclusive. A critical examination was made of 240 workers who were frequently exposed to the gas, but though the great majority of them were under par physically it was extremely difficult to decide how much of this was due to carbon monoxide and how much to such other factors, as unhygienic living, alcoholic excesses, etc. One constant and striking feature presented itself, however-a deficient muscular power, as indicated by the hand dynamometer.
This was so marked that a comparison was made between steelworkers and two groups of other workers. This gave the following results in 400 cases selected as being strictly comparable:
Ages 20-40. Steel company workers, South Chicago, exposed to CO, average strength, 117.13; ages over 40, average strength, 94.30.
Ages 20–40. Car company workers not exposed to Co, general hygiene, etc., good, average strength, 146.11; ages over 40, average strength, 127.35.
Ages 20-40. Workers in three companies not exposed to CO, general hygiene ordinary, average strength, 134.43; ages over 40, average strength, 113.01.
Mentally a majority of the men examined seemed below the average, but since nearly all used alcoholic liquors and 70 per cent admitted using them in excessive quantities, the investigators found it very difficult to decide what part in producing this condition should be ascribed to CO. “Since it is a well-known fact, however,” they say, "that prolonged exposure to carbon monoxide may produce a profound impression on the nervous system, we regard it as by no means improbable that a part of the sluggish mentality observed among the steelworkers may be due to frequent exposure to the gas. Further investigation along this line is to be strongly recommended.”
The prevalence of such exposure to the gas may be judged from the number of cases of gassing occurring yearly. At the time of the investigation the steel works were running at half or less than half of their full capacity. Of 10,000 men employed, 1,178 were working in the following departments and showed the following number of cases of poisoning:
The dangers arising from this form of poisoning are greater than either the frequency or severity shown in the above table indicate, since even a mild degree of poisoning produces unconsciousness and a consequent risk of falling, sometimes from a height, sometimes against hot furnaces or metals, or into other dangerous positions. "Of 22 men acutely gassed, 3 showed notable burns and 3 showed bruises.
One worker was burned almost to a crisp before being taken out, and another fell to his death 25 feet below. Many other illustrations like these could be given.”
The investigators find that within the past decade or two there has been a marked decrease in the cases of poisoning of this kind occurring in the Illinois Steel Works. This is partly due to the introduction of safer furnaces and methods of conveying gas, partly to greater care in keeping employees out of dangerous places, the use of oxygen helmets for those obliged to work in the most hazardous places, and the education of employees as to the dangers by oral or printed instructions. They recommend further precautions along the same or similar lines.
The effect upon health of turpentine as used in the painters and varnishers' trade forms the subject of a brief study by R. H. Nicholls and Drs. Flynn and Hayhurst. Observations were made upon a total of 62 men engaged in indoor branches of the work, because turpentine vapors are much less harmful when work is carried on in the open air. The age of those studied varied from 24 to over 60 years, only 9 being 51 years or over; the length of time they had spent at their trade varied from 2 to over 36 years. Nearly all claimed to have suffered from the effects of turpentine vapor more or less frequently; 14 were found to have organic diseases presumptively due to this cause, 21 had inflammation of the eye, 14 complained of respiratory symptoms, and 54 of urinary disturbances. According to their own statements these men had lost 1,098 days, representing about $5,200 in wages, through sickness from temporary effects, or actual acute Bright's disease following the inhalation of turpentine vapors. Five of the 62 had received benefits from their unions aggregating $236, but none had received any compensation from employers. Nine had sought charitable relief from dispensaries and hospitals. The particularly striking point in connection with these figures is that the loss, both physical and economical, involved in this form of industrial injury is absolutely unnecessary, since the simple measure of providing proper ventilation in places where the work is done would safeguard the men absolutely against the harmful effects of these fumes.
A report on caisson or compressed-air disease is presented by Dr. Peter Bassoe, who gives a résumé of the most important studies of the subject, with the results of a personal investigation of 167 men who had suffered one or more attacks of the disease. From a layman's point of view the most striking points about the disease are that its symptoms are unique, so that when a case occurs there is no danger of its being mistaken for something else; that its cause and nature seem to be fully established and that preventive measures are well understood and, when carefully enforced, are markedly successful. The disease seems to be directly due to the well-known law of physics that a liquid can hold in solution a volume of gas proportioned to the pressure of that gas in the atmosphere to which the liquid is exposed. While at work in compressed air the men are exposed to a heavier atmospheric pressure than in free air. Consequently their blood absorbs a larger volume of nitrogen—that being by far the most voluminous constituent of air—that it can hold in solution under normal pressure. If, then, a worker whose blood has become thus saturated with gas under the pressure of the caisson atmosphere passes into the decreased pressure of a normal atmosphere the gas may be set suddenly free, causing bubbles in the blood vessels, interfering with the circulation and sometimes leading to permanent injuries.
The preventive measures are threefold. First, there should be a careful selection of workers, as some are more susceptible than others. Young men are less apt to be affected than the middle aged, and men of spare build have an advantage over the fat. Men who already have any organic diseases are particularly liable to injury. Next, the time spent in the caisson should be inversely proportioned to the pressure under which work is carried on. And third, and possibly most important of all, the passage from the compressed to the natural air should be a gradual and graduated process, the men on leaving the caisson being kept in a lock in which the air pressure is gradually reduced until they may with safety pass out. How long this process should take depends both on the length of the working shift and the pressure to which the workers have been exposed. The New York law provides that decompression shall be at the rate of 3 pounds every two minutes, unless the pressure shall be over 36 pounds, in which event the decrease of pressure shall be at the rate of 1 pound per minute.
Only one method of treatment is known for this disease: Placing the sufferer again in compressed air, and, after keeping him there some time, gradually reducing the pressure. In severe cases it may be necessary to repeat this treatment several times. If it can be applied as soon as the characteristic symptoms manifest themselves it is usually strikingly successful.
In his personal investigations Dr. Bassoe found 161 men who had suffered from caisson disease, some of them having had several attacks. All but 20 of these had had severe pains, usually in the limbs, the so-called “bends." Thirty-four had had paralysis and 12 showed symptoms of some degree of permanent disease of the spinal cord. Eighty-seven had various affections of the ear, and 65 of these had resulting impairment of hearing. The most striking feature about the table is the comparatively short time in which the men, as a rule, had passed out from compressed to normal air.
The study closes with some suggestions for desirable legislation on the subject and the text of the laws regulating compressed-air work in New York and in Holland and in France.
In addition, the volume contains several studies dealing with rarer industrial diseases, and preliminary reports which, through lack of time, are too incomplete to indicate much more than the need for further investigation. Drs. Shambaugh and Boot made a study of occupational deafness, showing that danger of this exists in numerous lines of work where its presence is not generally suspected. Noiseproducing occupations are, of course, especially objectionable from this point of view, but the volume of sound seems to be of little importance as compared with its pitch. Shrill, high-pitched tones readily result in injury to the nerve of hearing, while low-pitched sounds, no matter what their volume, seem to work no harm.
Drs. Lane and Ellis examined 500 Illinois miners in a search for miners' nystagmus without finding a single case. Increased use of machinery and changes in method of mining, they conclude, are making this rare disease still rarer.
Dr. and Mrs. Matthew Karasek make a preliminary report on poisons used in photography, photo-engraving, silvering mirrors, and etching glass, and in their very brief outline indicate, in addition to what may possibly be necessary dangers, some wholly needless risks to which workers are exposed. For instance, among photoengravers, where the most deadly poisons are freely used, they found that very commonly there were “no posters, instructions, or warnings to employees regarding poisonous and dangerous chemicals; neither were labels present on any of the bottles containing potassium cyanide or other chemicals used in the rooms."
The report closes with a section on the legal side of the question, giving drafts of proposed laws for the regulation of some of the dangerous trades, and including an abstract of the chief provisions found in European legislation concerning the health and safety of workers. The commissioners are careful to explain that they regard the proposed laws only as a first step toward what should be accomplished. They recommend that the investigation be continued by the same or another body having more time and larger funds at its disposal.