Our laboratory explores the fate of contaminants in temperate and polar ecosystems in order to better predict their mobility and toxicity. Microbes exhibit tremendous and fascinating metabolic diversity. As such, we use them as sentinels of environmental perturbations and aim at a better understanding of their role as actors shaping the environment around us. Our current research topics focus on mercury (Hg), a potential potent neurotoxin, and iron (Fe), a key element in cellular and geochemical processes.

The overarching goals of our research are to determine how microbes interact with contaminants at the cellular level and to evaluate the consequences of these interactions at the ecosystem level. We are interested in how microbes sense and transform metals, particularly for detoxification, as well as how this information can be applied to the development of novel analytical and bioremediation tools.

1. Mercury biogeochemistry across latitudinal gradients 2. Microbes as catalysts of metal transformations 3. Development of a conceptual framework describing metal(loid)s bioavailability to microbes 4. Paleogenetic indicators of microbial exposure to toxic metals

Poulain, A.J., and Barkay, T. Cracking the Mercury Methylation Code. Science, 339: 1280-1281, 2013 Zdanowicz, C., Kruemmel, E.M., Lean, D.R.S, Poulain, A.J., Yumvihoze, E., Chen, J., Hintelmann, H. Accumulation, storage and release of atmospheric mercury in a glaciated Arctic catchment, Baffin Island, Canada. Geochimica Cosmochimica Acta, 107: 316-335, 2013 Lessard, C., Poulain, A.J., Ridal, J., and Blais, J.M. Steady state mass balance model for mercury in the St. Lawrence River near Cornwall, Ontario, Canada. Environmental Pollution. 174: 229-235, 2013 Brazeau, L.M., Poulain, A.J., Paterson, A.M., Keller, W., Sanei, H., and Blais, J.M. Recent Changes in Mercury Deposition and Primary Productivity Inferred from Sediments of Lakes from the Hudson Bay Lowlands, Ontario, Canada. Environmental Pollution, 173: 52-60, 2013 Daguené, V., McFall, E., Yumvihoze, E., Xiang, S., Amyot, M. and Poulain, A.J. Divalent base cations hamper bacterial HgII uptake.Environmental Science & Technology. Environmental Science & Technology, 46: 6645-6653, 2012