Symptoms and Signs of Workers Exposed to Benzene, Toluene or the Combination

Over 300 solvent workers (exposed to either benzene, toluene or the mixture) and about 130 non-exposed workers were examined for subjective symptoms, hematology, and serum and urine biochemistry. The mean time-weighted average exposure intensity was 33 and 59 ppm for benzene workers (for men and women, respectively), 46 and 41 ppm for toluene workers, and 14 ppm benzene + 18 ppm toluene and 18 ppm benzene +21 ppm toluene for mixture workers. The hematology was essentially normal except for marginal findings on WBC counts. Serum and urine biochemistry was not remarkable. The prevalence of subjective symptoms e.g. sore throat, headache and probably dizziness was dose-dependently elevated both in the benzene and toluene groups, whereas that of pancytopenia-related symptoms like gingival bleeding was not related to the intensity of benzene exposure.