PARENT SESSION
PT2 - Endocrine Disruption
Tuesday, 19 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P532) Development and application of tools to characterize endocrine disruptors in complex environmental mixtures.
Hewitt, Mark*,1, Parrott, Joanne1, MacLatchy, Deborah2, Pryce, Andrea3, Marlatt, Vicki3, Alsop, Derek3, Wood, Craig4, McMaster, Mark1, Munkittrick, Kelly2, Van Der Kraak, Glen3, 1 National Water Research Institute, Burlington, Ontario, Canada2 University of New Brunswick, Saint John, New Brunswick, Canada3 University of Guelph, Guelph, Ontario, Canada4 Nexfor Technology Centre, Pointe Claire, Quebec, Canada
ABSTRACT- We have been investigating the characteristics of bioactive substances present in complex effluents from pulp and paper mills across Canada. Our work has been developing on a number of research areas. In the first area of focus, we have developed a bioavailability model to study only those compounds accumulated by fish during controlled exposures. Bioactive compounds present in hepatic tissues of male white sucker (Catostomus commersoni) exposed to treated effluents from two Canadian pulp mills were investigated. Hepatic tissues were extracted and lipid-free extracts were fractionated according to octanol-water partition coefficient (Kow). Fractions were tested in vitro for the presence of compounds functioning as ligands for i) the Aryl hydrocarbon receptor (AhR) using mixed function oxygenase (MFO) induction in H4IIE cells, ii) the estrogen receptor (ER) isolated from rainbow trout (Oncorhynchus mykiss) liver, iii) the androgen receptor (AR) isolated from goldfish (Carassius auratus) testes and iv) sex steroid binding protein (SSBP) isolated from goldfish plasma. At both mills, fish displayed significant MFO induction after 4 d. Fish exposed to each effluent rapidly accumulated compounds with the ability to interact with sex steroid hormone receptors, indicating potential effects on hormone signaling and transport. In our second line of investigations, we have been focusing on individual process streams within the pulping process to identify bioactive substances. In this work we have developed a method which completely isolates compounds in chemical recovery condensates that depress steroids in fish. Finally, we have also been investigating the potential of whole effluent extracts to exhibit hormonal activity in steroid binding assays. The results to date show no correlation with effluent treatment and pulp production type with the presence or absence of these compounds.
Key words: endocrine disruptor, pulp mill effluent, bioavailability, complex mixture