The study covered 72 persons (39 females and 33 males), engaged in the production of dyes and varnishes, and exposed to mixtures of organic solvents which contain benzene C-9 and C-10 alkyl derivatives. For females--length of employment accounted for mean = 15.9 years and cumulative exposure index for mean = 12.11, and for males - mean = 16.4 years and mean = 12.17, respectively. The study results applying to the group exposed were compared with the results of the controls matched according to gender, age and work shifts. Clinical examination indicated that among complaints the following manifestations predominated: headache, dizziness, increased emotional excitability, memory and concentration disturbances, hypersomnia during a day and mood instability. Subjective symptoms were more frequently observed in females. Neurological examination revealed no organic changes neither in the central nor in the peripheral nervous system. Certain anomalies were noted in EEG and visual evoked potential (VEP) examinations which may indicate pre-clinical changes in the nervous system.