Concentrations of methylmercury in local wildlife could cause serious health effects
Canada is a world leader in hydroelectricity, using moving water to generate over 59 per cent of its total energy, yet, it remains somewhat of an afterthought for Canadians living in communities far away from hydroelectric operations and local food sources.
The process of conducting hydroelectricity, however, is endangering the health of nearby indigenous communities.
A recent study conducted at Harvard University concluded that reservoir flooding for the hydroelectric project in Muskrat Falls, N.L., will result in the concentration of methylmercury in nearby fish, birds, and seals to increase up to ten-fold. This increase will cause concentrations to exceed Canadian retail limits and guidelines set by the United States Environmental Protection Agency.
Methylmercury is produced when mercury reacts with bacteria from the rotting of vegetation in water. Methylmercury is even more toxic than inorganic mercury due to its tendency to absorb and accumulate in the tissues of organisms.
The Inuit communities near Muskrat Falls rely heavily on locally caught food sources, amplifying their exposure to methylmercury. Increased exposure can result in cardiovascular and immune issues, as well as negative impacts on cognitive development and function. Hyperactivity, decreased IQ, and impaired memory are some of the neurotoxic effects. Pregnant women, nursing mothers, and children are particularly at risk to these effects if exposed to concentrated levels of methylmercury.
In addition, 11 other hydroelectric sites in Canada were identified as having even higher methylmercury levels than Muskrat Falls. All the hydroelectric sites are within 100 kilometres of Aboriginal communities.
Indigenous populations in those regions consume high amounts of locally-caught wildlife, which, in some places, can be important to the communities’ health and culture.
The negative effects of hydroelectric projects can be minimized. According to the Harvard study, one technique is to remove the top layer of soil before flooding, which would be highly effective in decreasing the amounts of methylmercury formed. Science-based systematic monitoring and mitigation are needed to ensure that the wellbeing of indigenous communities in Canada is no longer sacrificed for broader energy benefits.
Photo courtesy of Innovationtrail (CC by NC 2.0).