Document MM8epdKk4d376po39VZRwVGex

FILE NAME: Newspaper & Magazine Articles (NMA) DATE: 1946 DOC#: NMA112 DOCUMENT DESCRIPTION: Journal Article - Dangerous Dusts - Science Digest A man may live near tKe railroad tracks all his life* and inhale the coal-black soot of the passing trains day after day without any damage to his lungs. Carbon from train smoke may make his lungs black as pitch and yet they will continue to function normally. He may live till the age of eighty or ninety only to die of some disease of his heart or intestines or some other organs. In spite of their blackness, the vitality of his lungs may be spared. On the other hand there are many instances where coal miners-- who are equally exposed to a carbon-laden at mosphere-- have succumbed to serious impairment of their lungs at the age of forty or fifty. If the lungs of these men are examined post-mortem, they too will be found to be heavily stained with coal-black pigment. Why do these men die? What is the difference between the carbon at the railroad tracks and the carbon in the coal mines? The answer can be found in one word-- silica. It is not the car bon that kills the coal miner, it is silicosis. Doctors have a name for these dust diseases of the lungs and, although it is a tongue-twister, it is a name Worth r '' remembering: pneu moconiosis. Silicosis is but one of them. Over one million workers in the United States today are exposed to one sort of dust or another. Pneumoconiosis is a major hazard in many industries. Silicosis is the most common--and perhaps most lethal-- form of pneu moconiosis. But don't think that it is a disease exclusively of coal miners. No indeed. Possible victims of the disease are those persons who are engaged in mineral grinding, rock quarrying; stone cutting, tunnel driving, fire brick manufacturing, foundry work, and the manufacture of tile and abra sive soap powders. There is hardly a state in the Union in which the problems associated with this disease have not presented them selves. In the Coeur d'Alene mining district of Idaho, in the fire brick, industry of Kentucky, in the anthra cite coal mines of Pennsylvania, and in the granite industry of Vermont, silicosis is a serious problem. The dangerous dust that causes sili cosis is silica-- ordinary sand! Chem ically it is represented by the formula Si0 2, which simply means silicon diox ide in chemist's shorthand. But here SCIENCE DIGEST 29 again we run into some problems. The :! beachcomber doesn't get silicosis and he may have sand blown at him all day. The window's at a Coast Guard station may be etched and scratched by particles of sand carried by the wind and yet silicosis is not a health hazard of the Coast Guard. What is the difference between the sand inhaled by the granite cutter and the sand inhaled by the beachcomber? | The answer is size. The sand (silica) in the stone quarry is very fine, like dust; the sand on the beach is coarse. Furthermore, and equally important, the man working in a stone grinding or polishing shed or in a mine is working in a closed space where the dust particles may accumu late in the air to astounding propor tions. Unlike the beachcomber he does ' not have the advantage of pure, clean ; air, swept in from the ocean. 1 Particles larger than four-millionths > of an inch in diameter cause no harm e since they are actually trapped within > the nose and throat and expectorated. r It is only when the dust particles are one-third of this size or smaller that n they get by the natural protective k barriers of the nose and throat and v enter the lungs themselves. ^ On the basis of repeated surveys K and examinations it has been discova' ered that there have to be about five 1 million particles of silica dust per lt' cubic foot in the air-- or more-- before !t can be regarded as a health hazard. v If the atmosphere is less heavily laden with dust, a normal man can appar1 a ently work at his job for years without )X' impairing his health. ;re The dangers from silicosis come from two sources-- from the disease it self and from a complicating infection with tuberculosis. Silica irritates the lungs, causing scarring which inter feres with the normal passage of air in and out of the lungs. This results in shortness of breath, coughing, and sometimes, feelings of weakness and fatigue. If the disease is extensive enough it may cause progressive dis ability and death. For some unknown reason, lungs that are affected with silicosis are more susceptible to T B . Statistics from various sources, as a matter of fact, indicate that about 6o per cent of the patients with silicosis develop TB as a complication. It is much more difficult to cure patients with silico- tuberculosis than uncomplicated cases. Besides, for them, the symptoms are usually more .severe, the cough is worse, the expectoration more annoy ing. Until recently the only method that doctors had for controlling silicosis was dust control. When possible " closed" spaces were eliminated. In other cases, blowers and vents rid the atmosphere of the dangerous dusts. Masks and other protective devices were invented. Doctors found too that by routine x-ray examinations they could detect evidences of the disease-- especially silico-tuberculosis-- before it had ad vanced too far. But, from a strictly medical standpoint, there was very little that could be done to cure the patient of his disease or arrest its ter rible progress. There was no specific medicine for the victim of silicosis. And then, in 1937, a group of Cana- dian researchers hit upon a brand new idea. They found that if they made experimental animals inhale finely powdered aluminum, it would protect them against silicosis. A t the same time, in this country, Dr. Leroy U. Gardner and his colleagues were work ing on the same problem at the Sara nac Laboratory using aluminum hy droxides or aluminum hydrates, instead of metallic aluminum. " Quite independently," says Doctor Gardner, "we discovered that hy drated alumina would also protect animals against quartz." Preliminary tests conducted on hu man subjects confirmed the fact that aluminum had a beneficial protective action. This was the first step in a long series of experiments that are still un der way, in an effort to demonstrate that aluminum has a curative as well as a protective action against this ter rible dust disease. A t present it seems as if both pow dered metallic aluminum and alumi num hydroxide are equally effective. Statistics released not long ago by Dr. J. W. G. Hannon reveal that of 143 disabled silicotic workmen, 135 im proved with aluminum treatment. Of 104 additional workmen whose x-rays showed silicosis but who were not as yet disabled by the disease, 93 im proved. In the disabled patients, treatment with aluminum brought about a de crease in the cough, less shortness of breath, and a diminution of chest pain. Why aluminum protects against silicosis is not known for certain. There is some evidence that the aluminum coats the dangerous silica parti with an infinitesimal layer of alu; num and thus prevents the irritaticij of the delicate lung tissues. Harm! -- so far, no serious toxic effects havi been noted-- aluminum stands as protective barrier between dangeroi silica and the lungs. Aluminum, even if it does prove be effective, is no substitute for dusSj control. Industry should continue tip make every effort to provide the work er with.a dust-free atmosphere or, at least, one that does not contain exces-. sive amounts of dangerous dusts. But silicosis is only one form of, pneumoconiosis. Another bad one asbestosis. The mineral, asbestos, front", which we get so much of our insulating materials, does not contain free silica;:-' but it is rather a complex silicate con taining iron, magnesium, and calcium In cases of asbestosis, if the lungs, are examined under the microscope, tiny particles of asbestos can be easily identified in the lung tissues. The as; bestos scars up the air passages, causes them to narrow and shrink in size to a fraction of their normal calibre. The result is difficulty in breathing, short ness of breath, and disability. In one state alone-- North Carolina -- there are about 500 persons engaged in the asbestos industry, and accord ing to one authority, many of them have already been found to be affected. Silicosis and asbestosis both have a marked tendency to get worse in time even if the person is removed from ex posure to them. Of course the amount of damage done varies from person to person and with the duration of the exposure. Some men can work in Dangerous Dusts 31 . particle; of alum l irritation ! Harmless fleets hate finds as dangeroin ! ? fs prove v :e for dm. ontinue to ; the workhere or, at tain exce;1dusts. ie form ot 1pad one is jestos, trom ; insulating !free silica, lilicate conid calciurr [ the iungi microscope m be east} es. The asiges, cause; in size to a alibre. The aing, shortity. tli Carolina >ns engaged ind accordny of them be affected, loth have ? irse in time ed from exthe amount n person to ,tion of the a work m mines all their lives without develop ing any disease; others will get a bad case of silicosis or asbestosis after a few years. The reason for this vari ability is still a medical mystery. Often, especially during the war, electric arc welders were seen com plaining of irritation of their nose and throat. A few of the men believed they had been "poisoned" by the fumes or had contracted TB. In most of these cases, x-rays of the lungs showed ab solutely nothing abnormal. As soon as these men were able to take a brief vacation or were able to get adequate rest or shorter working hours, their symptoms disappeared. The welding fumes had merely caused a local irritation of their upper respira tory tract but no real damage to their lungs. On the other hand, there were other welders whose lungs did show abnor mal changes on the x-ray. When their chest films were studied it looked al most as if someone had thrown a handful of sand at them or had pep pered them with a very fine buckshot. These men had " siderosis" --a con dition caused by inhaling fine particles of iron. These particles had become lodged within the lungs. That was why the lungs had a "peppered" ap pearance. But actually this excess iron had not made any of these men sick. Iron, unlike silica or asbestos, does uot irritate the lungs, does not cause them to scar up. In this way it is more !ke carbon. If the welding is done in pen rooms, the fumes do not become concentrated enough to cause changes within the lungs. If the welding elec- rodes are coated or if the welders em ploy protective masks, siderosis is pre vented. But even if siderosis does occur it does not lead to progressive disability. Recently, for example, Dr. O. A. San der of Milwaukee reported that a group of patients with siderosis whom he had followed for years showed very little change in their x-rays during that period. Apparently none of them had suffered as a result of the iron within their lungs. Cotton dust, strangely, may be irri tating to the lungs and may be respon sible for some of the respiratory ail ments of cotton mill workers. "Cottonmill fever," as the disease is called, first begins as a mild respiratory in fection. A curious point about the disease is that patients recover somewhat over the weekends, when they are not em ployed, and that symptoms are ag gravated on return to work on Mon days. For this reason the disease has also been called "Monday-morning fever." The cough grows worse, and there is progressive disability unless the pa tient changes his employment to some out-of-door work. Like so many of the dangerous dusts, cotton dust disease can be better prevented than it can be treated. There are some strange dusts that can make a person sick in ways that are still baffling and inexplicable. Such a disease is the one that is called " bagassosis." Bagasse is the product remaining after sugar is extracted from sugar cane. This material is commonly baled and if not used immediately may re- ' . S h ' :".'\'s- r T - * 32 SCIENCE DIGEST main exposed in the field for some months before being converted, by processing, into insulating and acous tic board. And it is the workers who are employed in breaking these bales that may become stricken with the disease. Since the first case of bagassosis was reported in medical literature only as recently as 1941, scientists have not yet had an opportunity to determine the exact nature of the illness. First it was thought that it wag a fungus con taminating the dust, and not the dust itself that was responsible. Other re searchers have believed that it was due to allergy. According to the latest bit of evi dence from Drs. W. A. Sodeman and R. L. Pullen of New Orleans, it is " spicules'' of the dust that get into the lung to cause the disease. Tiny slivers or "spicules" of bagasse can, appar ently, be very irritating to a person's lungs. In spite of ample provisions from Nature that guard our lungs from in jury by dangerous dusts, these provi sions are not always adequate. In the highly industrialized and mechanical life of modern society it is not always possible to avoid these dusts and to breathe " pure" air constantly. Yet present-day industrial engineers and modern industrial physicians are in creasingly aware of their responsibility for eliminating dangerous dusts from the atmosphere or of finding some effective treatments for those workers whose lungs are damaged. 0 & 9 t <9 9 COWARD K ILLER FISH e The piranha fish is "In tanks of the New York Aquarium we have attempted to y.-t rear several Piranhas at a time, probably the most allowing them space A vicious and blood far disproportionate thirsty creature of its size--some 6 or 7inches usually. e Piranhas have reduc to their size, but we ; 9 have found that in variably, sooner or later, they tear ed a 400-pound hog each other to bits--or I 9 to a skeleton in ten else some of them die of what ap e e minutes. Their teeth will nick hard pears to be fright. They have 9 9 steel. They are called " the fish that been found dead with no marks of 9 a a eat men." fighting or injury. Yet this same piranha lives a life " Even when kept in the same a a filled with terror, or whatever a fish tank but separated by a sheet of # feels in plaee of terror, according to glass, it is long before they learn Christopher W. Coates, curator of not to dash into hiding as soon as the New York Zoological Society's another pokes his head from be aquarium, in Animal Kingdom: hind a stone or cluster of plants."