Document zQyvkNDba6zxrLxor451KeK4g

I i Industrial Dust --The Pneumoconioses L E. HAMLIN, M.D., F.A.C.S., Medical Director, American Brake Shoe Company, Chicago i' The relation between dust and certain diseases of toxic and systemic effects, but usually their main con the lungs has been recognized for centuries, but sequence is local or irritant They do not cause pul only in recent years has it been given the intensivme onary fibrosis, but such things as dermatitis, dental study it deserves. In the fifth century B.c., Hippocrates lesions, irritations of the nasal mucous membranes, noted symptoms in ft metal digger, comparable to those and conjunctivitis are fairly common in workers han observed among present-day miners suffering from dling these materials. Digestive disturbances have silicosis. Since that time, other investigators have been observed. Allergic symptoms may occur in those recorded their impressions and observations on the exposed to pollens, horse hair, furs and wool,, and effects of inhaled dusts and have emphasized the asso various types of wood dust are known to affect suscep I ciation of these with tuberculosis. It was not until the tible persons. Bacteria such as the anthrax bacillus latter part of the nineteenth century, however, that are capable of producing cutaneous lesions, or "wool real interest in the subject was manifested. sorters* disease,'' when Inhaled. Sappington1 has listed To South Africa must be given the credit for the over 100 occupations which may produce exposure earliest serious contribution to our knowledge of the resulting in sllergy, asthma, or irritation of the akin industrial dust hazard. Here, in 1902, physical exam and upper air passages. inations were made on 3000 rock drillers and for the Fungi, such as mycelia and spores of molds, are apt first time, x-rays of the chest were used in a compre to cause rashes and painful fissures of the skin, while hensive study of 300 cases. Diagnostic standards of cotton weavers develop a form of disease known as <! disease, safe limits of particle'concentration in the air aspergillosis from inhiding spores of a mildew which of working places, and engineering methods for dust occasionally occurs on threads. ( control were instituted. Prom 1916 on, Great Britain, The inorganic dusts which have significance in Germany, Australia, Italy, Canada, and the United industry are derived mainly from minerals and metals. States made further investigations, but the most note In the process of grinding, crushing, blasting and worthy progress in these countries occurred during drilling these earthy substances, dust particles ranging the last few years. in size from microscopic to visible are liberated and Kronenberg and Morse1 have suggested the follow remain in suspension in the air for varying periods ! I ing classification of industrial dusts: depending on their size and settling velocity. Inhala i tion of those particles which contain silica in the ! Table I. uncombined state produces the type of pulmonary 1. Organic Dusts: A. Non-Living: 11. Inorganic Dusts: A. Toxic and (or) fibrosis known as silicosis. Gardner* demonstrated the specific action of silica and made it clear that only i 1. Toxic and (or) Irritant silica in the "free" state is capable of causing this Irritant. B. Fibrosis Producing. type of tissue reaction. B. Living: 1. Bacteria 2. Fungi. C. Non-Fibrosis Producing. The toxic inorganic dusts are those of the heavy metals and their salts, such as lead, mercury, man ganese, etc. They are usually considered under the Generally speaking, organic dusts originate from plants or animals, but many thousands of these sub stances are made synthetically. They may produce heading of industrial poisons rather than of dusts. The text or Dr. Hakun'* Lecture at the Second Poet-Graduate Courae in Industrial Medicine, Long Island College of Medicine, Brooklyn, Fridey, November 6, 1943. - SPNY 000228