Project Summary (2000-2006)

The goal of this project is to improve the understanding of the complex benzene metabolism in humans and its associated carcinogenicity. Researchers are extending development of cysteinyl protein adducts as biomarkers of exposure to the benzene intermediates benzene diol epoxide (BDE), and the muconaldehydes (MAHs). Existing methods are also being used to measure benzene and its metabolites in human urine and its protein adducts that are associated with the generation of reactive oxygen species (ROS) in vivo. These developments are contributing to the completion of a comprehensive set of benzene biomarkers that can be used to explore benzene exposure-biomarker relationships. Researchers are using these biomarkers to explore the magnitudes of interindividual variability in human metabolism and to evaluate the association between biomarkers and genotypic expression of several enzymes involved in benzene metabolism. Ultimately, these studies will provide information with which to gauge human metabolism and variability in the critical range of benzene exposure below 10 ppm.