Canadians are exposed to some 25 000 potentially toxic substances that the government is simply ill prepared to review, a report from the National Round Table on the Environment and the Economy (www .nrtee-trnee.ca/) states.
This “means we don't know if these substances are dangerous to health,” says Dr. Stuart Smith, chair of the independent round table, whose members were appointed by the prime minister. Its report, Managing Potentially Toxic Substances in Canada, urges Ottawa to bolster research with a $40-million grant to the Canadian Institutes of Health Research. Smith says it will also take an additional $50 to $70 million to move federal research capacity to the required level. “I don't want to be paranoid,” says Smith, “but you can't depend on what the company tells you, not when public safety depends on it.”
The 86-page report concludes that cuts in government staff and funding have thrust Canada into this predicament. Staff in the 4 science-based federal departments — Environment, Fisheries and Oceans, Health and Natural Resources — were cut by 17; between 1994 and 1998.
This reduced capacity to assess substances is compounded by significant advances in the scientific understanding of how substances in the environment affect human health (see CMAJ 2001; 164 [4];503-6). These advances often point to the need for more complex — and more resource intensive — assessments.
Many of the 25 000 substances, which include pesticides, food additives such as aspartame, and other chemicals, were approved before proper scientific understanding of their potential impact was available. Previously, testing concentrated on links to cancer and/or birth defects. “We have to look at other systems such as the nervous, immune and endocrine,” says Smith. “In particular, we have to know the effect on growing nervous systems of young children and adults.” He would also like to see testing begin on “chemical soups” — the additive or interactive combination of various substances.
The report says Canada's environmental decision-making is too fragmented, making it difficult for the government to address issues that cut across disciplinary boundaries and departmental mandates. The US has a more centralized system, with the Environmental Protection Agency (EPA) acting as a “watchdog on both environmental and human health issues,” according to Smith.
The report recommends creation of a policy-making Health and Environment Scientific Advisory Committee to support the Canadian Environmental Protection Act and the 8 other pieces of legislation that apply to toxic substances. This committee, which Smith describes as a “virtual EPA,” would suggest research priorities, identify emerging issues and provide a coordinated response to substances that fall under the jurisdiction of several pieces of legislation.