The Evolution of Canada's Approach to Minimizing Environmental and Health Risks from Mercury

In Canada, laws, regulations and guidelines limit the amount of mercury released to the environment via air, water, waste, and consumer products. In the environment, methylation of mercury increases its toxicity. The 1999 Canadian Environmental Protection act limits emissions from chlor-alkali plants. Transport of pesticides containing organomercury compounds is also limited by the act, and notification is required for unlisted compounds containing mercury. Because mercury also occurs naturally, it is not a candidate for total environmental elimination, but life cycle management is required. In the workplace, regulations limit occupational exposure. In addition, an initiative for companies to voluntarily reduce emissions of mercury to the environment was begun in 1992. Difficulties in tracing environmental input of mercury to anthropogenic and natural sources and in relating mercury levels in the air to bioaccumulated methylmercury in fish and other organisms exist. In addition, input of mercury to the atmosphere from volcanoes should be evaluated.