Les contaminants et leurs effets sur les baleines du Saint-Laurent
« Together we have the power to protect the ocean »: inspired by the theme of the World Oceans Day 2014, the Mériscope launches a multi-year research program on contaminants and their effects on minke whales and belugas of the St. Lawrence estuary, in close collaboration with other research groups, universities, Canadian federal authorities, and the Marine Mammal Stranding Network.
This 4-year program focuses on a group of emerging flame retardants that have been announced to be less toxic and biodegradable. Flame retardants, chemically speaking synthetic carbohydrates, are used in consumer goods (electronics, furniture, cloths, cars) and in construction materials. With industrial wastewater, these contaminants get into the marine environment and the food webs, at the top of which we find the marine mammals. The concentration of several dozens of these toxic substances and their effects on the transcription of genes in the cells of belugas and minke whales will be investigated in the framework of a number of scientific projects.
This broad and interdisciplinary research program is only possible thanks to the dedicated collaboration of our competent partners, particularly Dr. Magali Houde (Environment Canada), Dr. Jonathan Verreault (UQAM), Dr. Véronique Lesage (Dept. of Fisheries and Oceans Canada, DFO), Robert Michaud (GREMM), Dr. Pierre Béland (Saint-Lawrence National Institute of Ecotoxicology, SLNIE), Dr. David Janz (Univ. of Saskatchewan) and Dr. Peter Ross (Vancouver Aquarium).
The analyses of the tissue samples will be conducted in the framework of a PhD thesis (Antoine Simond) and two Master projects at the Université du Québec à Montréal (UQAM) and at the University of Saskatchewan. In a first phase, archived samples from the labs of DFO and SLNIE as well as skin, blubber, and liver samples from stranded animals will be analyzed. In the second phase, recent biopsies from minke whales and belugas shall also be included in the study, in order to document the increase of contaminants and their effects on protein synthesis in the cells.
The first generation of flame retardants, polychlorinated biphenyls (PCBs), were banned in Canada in 1997, because PCBs are toxic and non-biodegradable chemicals that accumulate in food webs. They have been replaced by a second generation of flame retardants, polybrominated diphenyl ethers (PBDEs), that were banned in 2006 for the same reasons as their precursors. Since, a third generation of flame retardants is being used in consumer goods, halogenated flame retardants (HFR), without in-depth tests of the biological effects of these chemicals. The manufacturers claim HFR to be less toxic, biodegradable and not bioaccumulative, but the first findings of Dr. Jonathan Verreault’s research show that the opposite is true.
The concentration of these flame retardants in the environment, animals and humans is now reaching alarming levels, and it increases exponentially with time. In the blubber of St-Lawrence belugas, the concentration of flame retardants doubles in three years, in some fresh water fish the interval is less than 20 months, and in humans it is approximately five years. Quite clearly, there are enough good reasons to do research on the bioaccumulation of these contaminants and their effects on the transcription of genes and on protein synthesis. The results of this research program will provide relevant scientific facts about flame retardants to authorities responsible for issuing efficient laws and regulations and for protecting our fresh waters and marine environments from further toxic contamination.