Analysis of emerging environmental contaminations using advanced instrumental tools : application to human and environmental exposure

High throughput analytical methods based on UPLC-APCI-HRMS and/or UPLC-ESI-HRMS were developed for the multi-residue analysis of pharmaceuticals, personal care products (PPCPs), brominated flame retardants (BFRs) and their degradation/transformation products. The PPCPs method was successfully applied to analysis of freshwater samples from Egypt. Target PPCPs were ubiquitous in the Egyptian aquatic environment and displayed relatively high concentrations in an effluent sample from a hospital wastewater treatment plant. The BFRs method was applied to screen for legacy BFRs, novel BFRs and their potential degradation/transformation products in simulated landfill leachate samples. In vitro bioassays were developed to study for the first time the metabolism of the novel BFRs TBECH by human liver microsomes and EH-TBB and FM550 by human skin S9 fractions. TBECH was metabolised by hepatic CYP450-mediated enzymes to produce a complex mixture of hydroxylated, debrominated and α-oxidation metabolites. EH-TBB and TPhP (in the FM550 mixture) underwent biotransformation by carboxylesterases in human skin S9 fractions. Kinetic modelling of the studied hepatic and dermal human biotransformation reactions revealed that exposure to multiple chemicals significantly influences the metabolic rates of target compounds. In vitro – in vivo extrapolations were also modelled to investigate the xenobiotic clearance capacities of human liver and skin.