Étudiant-chercheur étoile February 2013

Michel Lavoie

PhD student in Water Sciences

Award-winning publication: Influence of Essential Elements on Cadmium Uptake and Toxicity in a Unicellular Green Alga: the Protective Effect of trace Zinc and cobalt concentrations

Published in: Environmental Toxicology and Chemistry, 31(7):1445-52, juillet 2012


"Predicting the chronic toxicity of metals in freshwater ecosystems remains a major challenge since little is known about the specific factors that cause toxicity. Our laboratory experiments have demonstrated the key but often overlooked role of essential trace metals (chemical elements present in minimal amounts that are fundamental to proper biological processes) in the chronic toxicity of cadmium, a non-essential metal, to freshwater green algae. In fact, cadmium toxicity to C. reinhardtii may vary between 10 and 40 times depending on the amount of essential trace metals (e.g. zinc, cobalt, copper, manganese and iron) in the environment."

The biotic ligand model (BLM) currently used by the European Union and the United States to set water quality criteria for certain metals disregards the impacts of essential trace elements on metal toxicity. In the short term, the results of the research carried out by Michel Lavoie will help empirically account for the significant effects of essential elements on the toxicity of cadmium to phytoplankton. In the medium and long terms, the work will lead to scientific projects on other mechanisms by which essential trace elements modulate the toxic impacts of a metal. These mechanisms may be included in the BLM to better predict the toxicity of cadmium and other metals in water.