Effect-directed analysis of contaminated sediment from the wastewater canal in Pancevo industrial area, Serbia

Abstract

Wastewater canal (WWC) in Pancevo industrial area in Serbia, whose main environmental receptor is the River Danube, is a well known hot-spot of contamination. WWC sediments have been assessed by UNEP based on chemical target analysis. However, integrative biological data on exposure to hazardous compounds are only provided by the present study which aims at evaluating whether the monitored compounds sufficiently reflect potential hazards and to suggest additional compounds to include in monitoring and hazard assessment by applying effect-directed analysis (EDA) based on arylhydrocarbon receptor-mediated activity and cytotoxicity. Multistep NP-HPLC fractionation provided 18 fractions co-eluting with polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p-dioxins (PCDDs), polycyclic aromatic hydrocarbons (PAHs) and more polar compounds. PAHs fractions exhibited great potencies to induce ethoxyresorufin- o-deethylase (EROD) in H4IIE rat hepatoma cell line expressed as 2,3,7,8-tetrachlorodibenzo- p-dioxin equivalents (TCDD-EQ) (0.1–34.6 × 10 3 pg g −1 dry weight). Chemical analysis of the most active fractions revealed great concentrations of PAHs (up to 292 × 10 2 ng g −1 sediment equivalents (SEQ)), methylated PAHs (up to 900 × 10 2 ng g −1 SEQ), and other alkyl-substituted PAHs. Only minor portions of biologically derived TCDD-EQs could be attributed to monitored PAHs with known relative potencies (REPs). We hypothesize that a major part of the activity is due to non-monitored alkylated and heterocyclic PAHs. Results of the cell cytotoxicity/proliferation assay on H4IIE cell line suggest the presence of sediment pollutants with pronounced potency to disturb cell growth.