Document zdQEO2jRGe7ORqVMRe1pKKEx6

112 The Chemical Hazards of the acute phase. J. Occup. Med., patient exhibits restrictive pulmonary func /S:633,1976. tion.1 Accompanying clinical changes may 3. Levinsky, W. J., Smalley, R. V., Hillyer, include fine rales, finger clubbing, dyspnea, P. N., and Shindlcr, R. L.: Arsine dry cough, and cyanosis.1 hemolysis. Arch. Environ. Health,20:436, The onset of asbestosis probably depends 1970. upon the asbestos dust concentration, the 4. Teilelbaum, D. T., and Kier, L. C.: Arsine fiber morphology, and the length of expo poisoning. Arch. Environ. Health., 19: sure.3 Asbestosis is a progressive disease 133,1969. which may develop fully in seven to nine 5. Bulmer, F. M. R., el at.: Chronic arsine years and may cause death as early as 13 poisoning among workers employed in the years after the first exposure.3 Usually, the cyanide extraction of gold: a report of pneumoconiosis becomes evident 20 to 40 fourteen cases. J. Ind. Hyg. Toxicol., years after the first exposure to asbestos.3 22:111, 1940. Once established, the asbestosis progresses Supplemental even after the exposures have ceased.3 In its severe forms, death results from the inability 6. Grant, W. M.: Toxicology of the Eye. ed. of the body to obtain requisite oxygen or 2, p. 158. Springfield: Charles C Thomas, from the failure of the heart to pump blood 1974. through the scarred lungs.1 7. A.C.G.L.H.: Arsine. Documentation of Bronchogenic carcinoma and mesothelio the TLVs for Substances in Workroom ma of the pleura and peritoneum are causally Air. ed. 3, pp. 16-17. Cincinnati; 1976. associated with asbestos exposures; excesses of cancer of the stomach, colon, and rectum have also been observed.3 Among 632 asbes tos workers observed from 1943 to 1967, ASBESTOS 1977 TLV 5 fibers/cc > 5 p. in length OSHA Standard 2 fibers/cc > 5 p in length there were 99 excess deaths (above that ex pected-on the basis of the U.S. white male population) for three types of malignancies-- bronchogenic (63), gastrointestinal (26), and all other sites combined (10).4 Concern ing mesothelioma, 80 per cent of the cases studied in South Africa and the United King Synonyms: Asbestos is a generic term dom were shown to have had an occupation applied to a number of hydrated mineral sili al or paraoccupalional association with as cates, including chrysolite, amosile, crocido- bestos fibers.4 In the U.S., 14 deaths were lite, tremolite, and anthophyllite reported among 532 asbestos insulation Physical Form: Fibers of various sizes, col workers studied from 1943 to 1968, compared ors, and textures Uses: Thermal and electrical insulation; fire smothering blankets and safety garments; with no deaths, expected in the same number of similar individuals in the genera) popula tion.4 filler for plastics; cement Neoplasm, such as mesothelioma, may Exposure: Inhalation occur without radiologic evidence of asbes Toxicology: Asbestos causes asbestosis, tosis at exposure levels lower than those re cancer of the lungs and digestive tract, and quired for prevention of radiologically evi mesothelioma. dent asbestosis.4 Mesothelioma can occur Asbestosis is a lung disorder characterized after a short intensive exposure; cases of by a diffuse interstitial fibrosis, at times in mesothelioma in children under 19 years of cluding pleural changes of fibrosis.and cal age indicate the latent time period for de cification.1 Chest x-rays reveal a granular velopment of mesothelioma may be shorter change, chiefly in the lower lung fields; as than first estimated.4 'Mesothelioma tumors the condition progresses, the heart outline have yet to be successfully cured by any becomes shaggy, and irregular patches of types of treatment, including chemotherapy, mottled shadowing may be seen.' Asbestos radiation, or surgery; death usually results bodies may be found in the sputum, and the within a year of diagnosis.1 Information is in- SHIR i GLEASON-000060