Detection of estrogen- and dioxin-like activity in pulp and paper mill black liquor and effluent using in vitro bioassays
- Univ. of Western Ontario, London, Ontario (Canada). Dept. of Pharmacology and Toxicology
Pulp and paper mill effluent contains a complex mixture of compounds which adversely affect fish physiologically and at the population level. These effects include compromised reproductive fitness and the induction of mixed-function oxidase activities; two classic responses mediated by the estrogen and/or Ah receptor. In vitro recombinant receptor/reporter gene assays were used to examine pulp and paper mill black liquor and effluent for estrogenic, dioxin-like and antiestrogenic activities. Using MCF7 cells transiently transfected with a Gal4-estrogen receptor chimeric construct (Gal4-HEGO) and a Gal4-regulated luciferase reporter gene (17m5-G-Luc), it was estimated that black liquor contains 4 {+-} 2 ppb ``estrogen equivalents``, while negligible estrogenic activity was observed in a methanol-extracted pulp and paper mill effluent fraction (MF). A dioxin response element (DRE)-regulated luciferase reporter gene (pGudLucl.1) transiently transfected into Hepalclc7 wild type cells exhibited a dose-dependent increase in luciferase activity following treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDO), black liquor and MF. Based on the dose response curves, black liquor and MF contain 10 {+-} 4 ppb and 20 {+-} 6 ppt ``TCDD equivalents``, respectively. Moreover, MF exhibited significant AhR-mediated antiestrogenic activity. These results demonstrate the utility of these bioassays and suggest that the effects observed in fish exposed to pulp and paper mill effluent may be due to unidentified ER and AhR ligands not detected by conventional chemical analysis due to the lack of appropriate chemical standards.
- OSTI ID:
- 244858
- Report Number(s):
- CONF-9511137-; ISBN 1-880611-03-1; TRN: IM9627%%180
- Resource Relation:
- Conference: 2. Society of Environmental Toxicology and Chemistry (SETAC) world conference, Vancouver (Canada), 5-9 Nov 1995; Other Information: PBD: 1995; Related Information: Is Part Of Second SETAC world congress (16. annual meeting): Abstract book. Global environmental protection: Science, politics, and common sense; PB: 378 p.
- Country of Publication:
- United States
- Language:
- English
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