Summary The health status of 1515 workers employed in heat production was investigated. The subjects studied were divided in four groups according to occupation and occupational risk factors: vibration, noise, dust, metal aerosols, overloading of the musculoskeletal and peripheral nervous system, and organic solvents. The control group included 152 administrative staff members. High prevalence of socially significant diseases – cardiovascular, endocrine and metabolic was detected in all the groups surveyed. The frequency of diseases of the cardiovascular system and the respiratory system was 2.7 times higher than that in the control group. Statistically reliable higher prevalence of lung diseases in the studied risk groups was found, especially in the group of welders and chemists: 45.3% и 17.4% respectively, as compared to 4.3% in the controls. These finding corresponded to the occupational risk. The following occupation diseases were diagnosed: pneumoconiosis in 26.6% and toxic pneumofibrosis in 5.1% of electric welders. As regards the group of chemists, toxic pneumofibrosis was found in 6.5%. toxic effects of irritants - in 6.5 %, and chronic intoxication with organic radicals - in 0.7 % of them. Occupational auditory neuritis was diagnosed in 1% of the turbine operators and crane operators. The relative share of workers with peripheral nervous system pathology (radiculopathies, polyneuropathies, distal sympathetic neuropathy, mononeuropathy) was reliably higher than that in the control group, and the frequency increased among the workers with more than ten years of service and older than 40.

Summary A clinical observation of 15 workers exposed to lead, engaged in recycling of lead accumulators, was carried out. The exposition to lead aerosols varied from 2 months to 14 years. High levels of lead absorption and excretion after application of antidote therapy were found in all workers followed up. There were no manifestclinical signs and symptoms in 7 workers whom we suspected to be lead carriers. Anemia was diagnosed in 8 of the investigated persons. Severe form of intoxication, including paresis of both radial nerves, was established in one worker. Subacute lead poisoning, presenting with lead colic, anemia, toxic hepatitis and toxic polyneuropathy, was diagnosed in three persons with only several months of intensive lead exposure. Association between lead exposure, metal absorption and clinical symptoms in investigated persons were discussed.