Hard-metal fibrosis

Hartung M, Schaller KH and Brand E (1982) On the question of the pathogenic importance of cobalt for cobalt hard metal fibrosis of the lung. Int Arch Occup Environ Health 50 53-57. 

Cobalt compounds can be classified as relatively nontoxic (33). There have been few health problems associated with workplace exposure to cobalt. The primary workplace problems from cobalt exposure are fibrosis, also known as hard metal disease (34,35), asthma, and dermatitis (36). Finely powdered cobalt can cause siUcosis. There is Htfle evidence to suggest that cobalt is a carcinogen in animals and no epidemiological evidence of carcinogenesis in humans. The LD q (rat) for cobalt powder is 1500 mg/kg. The oral LD q (rat) for cobalt(II) acetate, chloride, nitrate, oxide, and sulfate are 194, 133, 198, 1700, 5000, and 279 mg/kg, respectively the intraperitoneal LD q (rat) for cobalt(III) oxide is 5000 mg/kg (37). 

Toxicology. Cobalt causes skin irritation, allergic contact dermatitis, and occupational asthma interstitial pulmonary fibrosis is associated with exposure to hard metal dust (tungsten and cobalt). 

More recently, mngsten oxide fibers have been detected in a hard metal production plant. Subsequent in vitro experiments showed that the tungsten oxide fibers were cytotoxic to human lung cells. The role of tungsten in the development of hard metal dust pulmonary fibrosis remains unclear. 

Cobalt is an essential nutrient at low levels ( 40mgday ). In industrial settings, inhalation of high concentrations of cobalt compounds has led to hard-metal pneumoconiosis, which may result in interstitial fibrosis. Workers with this condition typically develop hypersensitivity to cobalt compounds (symptoms include coughing and wheezing). A few workers have developed skin hypersensitivity after dermal contact with cobalt and its compounds. Cobalt can cause cardiomyopathy and (if inhaled as a dust) interstitial lung disease. 

Diffuse pulmonary fibrosis ( hard metal disease ), loss of appetite, nausea, cough, blood changes. No... 

Cobalt combined with tungsten carbide forms a hard metal used for the cutting tips of machine tools and drills. Inhalation of the dust may give rise to fibrosis of the lungs causing cough, wheezing and shortness of breath. 

Migliori M, Mosconi G, Michetti G et al (1994) Hard metal disease eight workers with interstitial lung fibrosis due to cobalt exposure. Sci Total Environ 150 187-196... 

For similar routes and forms of mercury, the adverse health effects seen in children are similar to the effects seen in adults. For example, a young child who was intoxicated with mercury vapor, died of pulmonary edema and had a grayish, necrotic mucosa of the stomach and duodenum (Campbell 1948). These effects are similar to those seen in adult populations occupationally exposures to inhaled metallic mercury vapors. Respiratory effects in adults from inhalation of metallic mercury vapor include pulmonary edema, lobar pneumonia, fibrosis, desquamation of the bronchiolar epithelium, and death in severe cases due to respiratory failure (Gore and Harding 1987 Jaffe et al. 1983 Kanluen and Gottlieb 1991 Matthes et al. 1958 Taueg et al. 1992 Teng and Brennan 1959 Tennant et al. 1961). 

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