Using combined bio-omics methods to evaluate the complicated toxic effects of mixed chemical wastewater and its treated effluent

• Mice exposed to mixed chemical wastewater and its treated effluent for 90 days.
• Hepatic transcriptomic alterations were analyzed by digital gene expression.
• Serum metabolomic alterations were analyzed by proton nuclear magnetic resonance.
• The water samples induced disruption of lipid metabolism and hepatotoxicity.
• Omics approaches are valuable to evaluate the complicated toxicity of wastewater.

Mixed chemical wastewaters (MCWW) from industrial park contain complex mixtures of trace contaminants, which cannot be effectively removed by wastewater treatment plants (WWTP) and have become an unignored threat to ambient environment. However, limited information is available to evaluate the complicated toxic effects of MCWW and its effluent from wastewater treatment plant (WTPE) from the perspective of bio-omics. In this study, mice were exposed to the MCWW and WTPE for 90 days and distinct differences in the hepatic transcriptome and serum metabolome were analyzed by digital gene expression (DGE) and proton nuclear magnetic resonance (1H-NMR) spectra, respectively. Our results indicated that disruption of lipid metabolism in liver and hepatotoxicity were induced by both MCWW and WTPE exposure. WTPE is still a health risk to the environment, which is in need of more attention. Furthermore, we demonstrated the potential ability of bio-omics approaches for evaluating toxic effects of MCWW and WTPE.