Effects of benzene exposure on hematological parameters shoe-manufacturing workers in Bogor, West Java

Benzene is pollutant well-known to be a carcinogen. Recent studies have shown that low-level benzene exposure can affect the hematological system. The present study examined the relationship between low-level benzene inhalation exposure and neutrophil counts in shoe-manufacturing workers. Segmented-neutrophil counts were measured in blood samples from 78 benzene-exposed workers in Bogor. Benzene exposure was measured according to S-phenylmercapturic acid (SPMA) concentrations in urine samples. Demographic data, exposure, and blood test data were analyzed using Pearson's chi-square test. The results showed that the average age of the study population was 29 years (range 18-56 years). The average SPMA concentration was 1.618 μg/g creatinine but the SPMA concentration varied considerably. No correlation was found between neutrophil counts and other characteristics of the subjects. The odds ratios (ORs) indicates that the workers even with low SPMA concentrations were at risk of having abnormal segmented-neutrophil counts. The workers with fair SPMA concentrations were 4.5 times more likely to have abnormal segmented-neutrophil counts. These data suggest that low-level benzene exposure may be hemotoxic. A longitudinal study with direct measurements of workers' benzene exposure is needed to confirm the toxicity of low-level benzene exposure.