Transcriptome analysis in human blood as a biomarker pollution through drinking water. They found differential expression between groups with low-, intermediate-, and high-arsenic exposure, in particular, inﬂammation-related genes showing up-regulation with increasing exposure. In addition, gene expression proﬁl- ing has been used to examine the risks of occupational exposures to benzene and metal fumes (Forrest et al. 2005; Wang et al. 2005). However, these studies did not include as many study subjects as the present study. Conclusions In this large cross-sectional study, we have demonstrated the potential of gene expression analysis for monitoring in relation to environ- mental carcinogenic exposures in humans. We found that a gene expression profile differed significantly between human populations according to their environmental exposure. Many correlations between gene expression and blood or urinary measures of biomarkers of exposure to environmental carcinogens were observed. 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