Risk Ratio of Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) Exposures and Their Relations to Biological Parameters of Gasoline Workers in Bangkok, Thailand

Abstract

Gasoline station is a common source of volatile organic compounds (VOCs) emissions around its perimeter. In order to conduct a monitoring of the VOC’s emission, measurements of biological markers of blood benzene, toluene, ethylbenzene and xylene (BTEX) in gasolinestation workers are recommended. The purposes of this study were to evaluate exposure risk ratio (110 gasoline station workers from 11 gasoline stations in Bangkok Metropolitan area compared to 10 office workers in the same station as control group) and to determine the relations between blood BTEX and biological parameters of the gasoline workers. Results showed that blood BTEX levels of gasoline workers were significantly higher than controls (independent t-test, p < 0.001). Most measurements of toluene, ethylbenzene and xylene (TEX) in female workers were significantly higher exposed levels than in men (independent t-test, p < 0.01). The highest risk ratio of BTEX environmental exposures was benzene. In addition, blood benzene was the most significantly correlated to toluene (partial correlation = 0.704, p < 0.001), but was not related to all biological parameters in this study.