Evaluation of Benzene Exposure and S-Phenylmercapturic Acid (S-PMA) as a Biomarker of Exposure to Workers in the Informal Footwear Industry

Benzene (C6H6) is one of the most widely used chemical compounds in the world. Although its use has been limited, humans may be exposed to benzene in the natural and industrial environments. Small-scale footwear industry still uses adhesives containing benzene. The benzene profile has been well-documented, and it has been classified as a carcinogen compound. The purpose of this study is to assess the risk of benzene exposure in the work environment and individual exposure in footwear factory in Ciomas, Bogor, West Java, during August–September 2017. Urine test with S-Phenylmercapturic Acid biomarker was performed on 40 workers and measurements performed simultaneously at 9 air sample points from 3 workshop locations in accordance with NIOSH 1501 method, risk-level assessment through calculation Risk Quotient (RQ) and Excess Cancer Risk (ECR). The S-PMA subject has not exceeded the exposure limit (>25 μg/g) as Biological Exposure Indices (BEIs) with a median value of 0.190 μg/g (min 0.019–max 17.61). The results of the air sample analysis showed 8 sampling points below the TLV (Threshold limit values) of 0.5 ppm (1.6 μg/m3) and 1 point of air sampling has exceeded 0.5 ppm (1.6 μg/m3) of 2, 1074 ppm. the result of calculation of minimum cancer risk, it has been obtained that 13 workers (32.5%) have cancer risk that has exceeded the reference value (ECR>1 ⋅ 10−4) and 27 (67.5%) have ECR < 1∙10−4. In the calculation of real-time non-cancer risk, it has been obtained that 8 (20%) workers have had non-cancer risk (RQ>1) and 32 (80%) have RQ<1. The concentration of air and S-PMA of workers is still below the TLV, but considering the risk of cancer and non-cancer workers who have exceeded the reference value, it is necessary to improve the working conditions.