| Project Title |  |
| Project I1: Detection of
metal-induced effects in indigenous fauna.
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| Research Team | |
| Peter G.C. Campbell
(Université du Québec, INRS-Eau) - PI Email: peter_campbell@inrs-ete.uquebec.ca Collaborators: Laurie Chan (McGill University);
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| Project Summary | |
| Attempts to define the impacts of metals
on aquatic ecosystems have traditionally involved laboratory experiments under defined
conditions (toxicity tests) and, to a lesser extent, field observations on impacted
indigenous populations (abundance; condition; growth; reproduction). To link these two
approaches, one needs a common measure of metal exposure in laboratory and field settings.
The determination of metal concentrations or burdens in tissues (or whole organisms) has
been suggested as a means of achieving this linkage. In the present project, we propose to
explore this approach with aquatic biota, and to expand the concept of metal "body
burden" to take into account the speciation of the metal within the organism, i.e.
the organism's ability to detoxify the metal. The aquatic biota to be considered include
benthic invertebrates, indigenous fish and waterfowl. A Links between metal body burdens in aquatic invertebrates and metal-induced toxicity. Dixon and Borgmann Background: Total metal concentrations in the environment do not provide accurate estimates of effects because toxicity is a function of metal bio-availability. Since biological effects usually follow, and are the result of bioaccumulated metal, body concentrations should be better predictors of effects than concentrations in water or sediments. Several studies have already shown this to be the case. The problem is more complex in the case of essential metals such as copper and zinc, which are regulated to varying degrees in different aquatic organisms. B Links between tissue body burdens in indigenous fish and metal-induced effects at the organism and population levels. Campbell, Hontella, and Rasmussen Background. Over the period 1999-2003 (4 years), this sub-project is designed to test the prediction that relations between metal body burdens in indigenous fish and metal-induced effects at the organism, population and community levels will be improved if the metal body burdens are expressed not as total metal, but rather in terms of the metal's partitioning within particular target tissues. C Metals in waterfowl and other wild birds in Northern Ontario and Northern Quebec. Chan and Scheuhammer Background. Waterfowl and other water birds, such as loons, are important species to be included in environmental risk assessments of aquatic environments. These birds can serve as good indicators of the health of the wetlands in which they are found. Depending on their feeding habits, they may be exposed to high concentrations of metals through dietary intake in metal-contaminated environments. In MITE2, we will study the relationships between body burdens of metals and potential toxicological effects such as reproductive dysfunction. An understanding of the potential detoxification mechanism for methylHg is an important factor for risk assessment purposes. There are no data on Hg/Se speciation in waterfowl or loons. The preliminary data on Hg/Se speciation will help to develop protocols for studying effects of Hg exposure in the birds.
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