Investigating the significance of dissolved organic contaminants in aquatic environments: Coupling passive sampling with in vitro bioassays

• Published in: Chemosphere (Oxford) Vol. 90; no. 2; pp. 210 - 219
• Main Authors: Emelogu, Emmanuel S., Pollard, Pat, Robinson, Craig D., Smedes, Foppe, Webster, Lynda, Oliver, Ian W., McKenzie, Craig, Seiler, T.B., Hollert, Henner, Moffat, Colin F.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.01.2013; Elsevier
• Subjects: acute toxicity; Agnatha. Pisces; agricultural watersheds; Animal, plant and microbial ecology; Animals; Applied ecology; aquatic environment; aquatic organisms; bioassays; Biological and medical sciences; cost effectiveness; Cytochrome P-450 CYP1A1 - metabolism; cytotoxicity; Dioxins - analysis; Dioxins - toxicity; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Environmental Monitoring - instrumentation; Environmental Monitoring - methods; estuaries; Fresh Water - chemistry; Fundamental and applied biological sciences. Psychology; Hydrophobic and Hydrophilic Interactions; Hydrophobic organic contaminants; hydrophobicity; liver; Monitoring; Oncorhynchus mykiss; Oncorhynchus mykiss - metabolism; Organic Chemicals - analysis; Organic Chemicals - toxicity; Passive sampling; Pesticides - analysis; Pesticides - toxicity; polychlorinated biphenyls; polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Polycyclic Aromatic Hydrocarbons - toxicity; rubber; Scotland; silicone; Silicone rubber; streams; surface water; Toxic equivalency (TEQ); urea herbicides; Water; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; water pollution; water quality; Scotland; Water; Hydrophobic organic contaminants; Toxic equivalency (TEQ); Passive sampling; Silicone rubber; Monitoring; Enzyme inducer; Isozyme; Toxicity; Persistent organic pollutant; Passive detection; Aquatic environment; Pisces; Adsorbent; Sampling; Silicone elastomer; Unspecific monooxygenase; Bioassay; Ecotoxicology; Enzyme; Cytochrome P450; Pesticides; Polychlorobiphenyls; Hydrophobic compound; Polycyclic aromatic compound; In vitro; Vertebrata; Cell line; Toxic equivalency factor; Drug-metabolizing enzyme; Skin; Oxidoreductases; Fibroblast
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2012.06.041

► PAHs and PCBs were determined in a rural catchment using passive sampling. ► Semi-polar pesticides and herbicides were detected using silicone rubber samplers. ► Coupling passive sampling with in vitro tests enabled evaluation of mixture effects. ► No cytotoxicity was observed in RTL-W1 cells exposed to passive sampler extracts. ► EROD activity was measured; only 12–21% of this was attributed to PAHs and PCBs. We investigated the feasibility of coupling passive sampling and in vitro bioassay techniques for both chemical and ecotoxicological assessment of complex mixtures of organic contaminants in water. Silicone rubber passive sampling devices (SR-PSDs) were deployed for 8–9weeks in four streams and an estuary of an agricultural catchment in North East (NE) Scotland. Extracts from the SR-PSDs were analysed for freely dissolved hydrophobic organic contaminants (HOCs) and screened for wide range of pesticides. The total concentrations of dissolved PAHs (∑PAH40, parent and branched) in the water column of the catchment varied from 38 to 69ngL−1, whilst PCBs (∑PCB32) ranged 0.02–0.06ngL−1. A number and level of pesticides and acid/urea herbicides of varying hydrophobicity (logKOWs ∼2.25 to ∼5.31) were also detected in the SR extracts, indicating their occurrence in the catchment. The acute toxicity and EROD induction potentials of SR extracts from the study sites were evaluated with rainbow trout liver (Oncorhynchus mykiss; RTL-W1) cell line. Acute cytotoxicity was not observed in cells following 48h exposure to the SR extracts using neutral red uptake assay as endpoint. But, on a sublethal level, for every site, statistically significant EROD activity was observed to some degree following 72h exposure to extracts, indicating the presence of compounds with dioxin-like effect that are bioavailable to aquatic organisms in the water bodies of the catchment. Importantly, only a small fraction of the EROD induction could be attributed to the PAHs and PCBs that were determined. This preliminary study demonstrates that the coupling of silicone rubber passive sampling techniques with in vitro bioassays is feasible and offers a cost effective early warning signal on water quality deterioration.