Prof Lent Expertise, Chaired Pesticides Panel

January 17, 2012 - News Release

An international expert panel chaired by a now-retired University of Guelph professor released a report today calling for improvements to Canada’s strategies for assessing and regulating the risks of pesticides.

The panel was assembled in 2009 following a request by the federal minister of health for Canada’s Pest Management Regulatory Agency (PMRA).

Len Ritter, a world-leading toxicologist in U of G’s School of Environmental Sciences, headed the group of 15 scientists from Canada and the United States. The panel was formed by the Council of Canadian Academies, a non-profit group that supports expert assessments to public policy.

Elizabeth Dowdeswell, president and CEO of the Council of Canadian Academies, said the panel’s assessment was “exhaustive. We are confident that the report will provide the evidence needed to assist PMRA and other regulatory organizations as they consider the future of chemical testing in Canada and globally.”

The report, “Integrating Emerging Technologies Into Chemical Safety Assessment,” is available online. It identifies a need to strengthen regulatory decisions based on the best available science.

Although the active ingredients in pesticides are among the most stringently regulated compounds on the market, the report said, toxicity data are lacking for the majority of industrial chemicals.

Many current toxicity tests were developed more than 30 years ago based largely on testing of lab animals. Those tests have changed little since and are inadequate to address the backlog of data-poor chemical compounds, the report said.

The report calls for integration of wide-ranging tools and techniques for testing and assessing chemicals. That integration would help in ranking of high-risk chemicals and development of toxicology profiles to inform regulatory decisions, and would also help in assessing the safety of data-poor chemicals, the report said.

Such changes would improve protection of human health and the environment, Ritter said. “Science is advancing in such a way that we now have a deeper understanding of physiology. In order to keep pace with international practices, there is an opportunity for Canada to embrace and integrate new technologies and approaches into current chemical testing practices.”

Ritter has worked with the federal and provincial governments on a number of scientific reviews. Last year, he was appointed to lead an independent fact-finding panel on the use of the 2,4,5-T herbicide by Ontario ministries and agencies.

A U of G professor since 1993, Ritter retired in June 2011. Before joining U of G, he held various positions at Health Canada, including director of the bureau of veterinary drugs, chief of the product safety division and chief of the pesticides division.

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