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Sylvain DeGuise, D.M.V., Ph.D. (

My research is in comparative pathology, immunology and immunotoxicology of aquatic organisms to understand how different aquatic animals are able to respond to pathogens in view of the particularities of their physiology and their response to environmental stressors, at the individual to population levels. Work in my laboratory focuses on marine mammals, oysters and lobsters, in addition to the recently added study of effects in humans, who increasingly depend on the aquatic food chain. Current projects directly related to Oceans and Human Health include the following:

1. Comparative Immunotoxicity of PCBs in Marine Mammals, Humans and Mice upon In Vitro Exposure as a New Tool for Risk Assessment. Recent studies in our and other laboratories have demonstrated significant differences between species in their response to environmental pollutants, and differences between the effects of PCB congeners, which appear to sometimes modulate their effects via dioxin-independent mechanisms. This study aims at evaluating and comparing the species- and congener-specific effects of different PCB congeners upon in vitro exposure to quantify differences between species (and objectively address whether or not the mouse model can accurately predict effects in other target species such as marine mammals and humans), and use those results for species-specific and mechanistically-based risk assessment in view of the concentrations of such PCBs in tissues of target species following environmental exposure.

2. Immunotoxicology of Manufactured Nanomaterials. Nanomaterials are rapidly evolving and making their appearance in consumer products. Nevertheless, the evaluation of the potential toxicity of those nanomaterials has never evolved at the same pace as that for the development of new products and applications. Our lab is working on the assessment of the immunotoxic effects of different nanomaterials to try to understand the physico-chemical characteristics responsible for their toxicity.

3. Comparative Immunotoxicity of Brominated Flame Retardants and Perfluorinated Compounds. Brominated flame retardants and perfluorinated compounds are accumulating in human and wildlife tissues at alarming rates, yet relatively little is know about their toxic potential. Our lab has undertaken the study of the immunotoxic potential of those environmental contaminants in a congener- and species-specific manner for use in comparative risk assessment.

4. Health Effects of Harmful Algal Bloom Biotoxins. Harmful algal blooms are increasing in frequency, and while some acute health effects have been well documented in laboratory animals, humans and some species of marine mammals, there is much to be learned about their sub-acute and chronic health effects. Our lab is engaged in the determination of the sub-acute to chronic health effects of domoic acid on immune functions of marine mammals.