[Evaluation of neurological status and EEG tests in workers exposed to metallic mercury vapors]

Workers occupationally exposed to mercury vapours were examined. Concentrations of mercury vapours in the air in a plant producing thermometers did not exceed 0.02 mg/m3 whereas in a plant producing electrical lamps they ranged from 0.02 to 0.05 mg/m3. Most of the workers complained of nervous system disorders, especially of headaches, hypersensibility, dyssomnia, paresthesias. Subjective changes in form of some marks of central and peripheral nervous system impairment were found in more than 40% of working women exposed to mercury vapours, whereas in the control group--only in 4%. The symptoms of the central nervous system impairment were more frequent and diversified in the group of women working in the plant producing electrical lamps. In the EEG tests abnormal electroencephalograms amounted to 44.5%. The most frequent changes were of generalized nature (24.0%). Paroxysmal changes in form of the discharge of dysrhythmical function of theta and sharp waves, were found in 16.6%. In the control group changes in electroencephalograms were less frequent and comprised only 15.3% of those tested. Generalized and paroxysmal changes were also less frequent, 10.7% and 4.0%, respectively.