[Fibrogenic and general toxic effects of copper and nickel sulfide ore dust (data for a hygienic evaluation)].

Experiments on acute and chronic inhalation of copper and nickel sulfide ore dust proved that the dust of rich ore, if compared with that of copper-bearing and impregnated ore, induces more marked toxic effects. Intratracheal administration of all the dust types, 50 mg, and inhalation of the high concentrations (102 mg/cu m in average) induced fibrogenic effects. The dust of rich ore induced more marked fibrogenic reaction in lungs, in 3 months after 6-month period of inhalations stopped that reaction disappeared. General toxic effects caused by the dust either of rich ore or impregnated ore were mild. Justifying the MAC requires consideration of possible carcinogenic effect.