Changes to pesticide testing could take years

Tuesday, January 31, 2012

by SUSAN MANN

It could take 10 years or more for Canada to integrate new technologies in its pesticide testing and assessment program indicates a recent study.

Olivia Caron, Health Canada media relations officer, says by email that’s because many of the tools needed “for this approach are still under development and will require several years of testing and validation before they can be considered to be reliable enough to be fully adopted.”

Adopting a diverse approach to assessing chemicals would enhance the reliability of existing testing and make it possible to assess chemicals that haven’t received extensive analysis, the study from the 15-member panel of Canadian and U.S. scientists concludes.

The report’s executive summary explains that although pesticides undergo stringent testing, a full battery of toxicity tests for the solvents and adjuvants regularly added to pesticide products is rare. These chemicals are added to improve the product’s “physiochemical properties, enhance their use or increase their stability,” the report says. As a result, the final pesticide product contains a combination of data-rich and data-poor chemicals.

Panel chair Len Ritter, a retired University of Guelph professor, says in a January press release from Health Canada announcing the study’s conclusions that “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.”

The integration of wide-ranging tools and techniques in chemical testing and assessment would help regulators assess the safety of the data-poor chemicals and that change would improve protection of human health and the environment, the report’s summary notes.

Other approaches that could eventually be added to the animal studies currently used for assessments include cellular and biochemical screening tests and predictive models.

Pierre Petelle, vice president of chemistry for CropLife Canada, says the industry already uses the best available science. Canada participates at the international level with other Organization for Economic Co-operation and Development countries to look at how pesticides are evaluated, including the type of approaches and the type of data that’s studied. “We’re at the cutting edge in our scientific approach to pesticide regulation,” he says.

However, if combining different evaluation technologies does “have a fit for pesticides then obviously we will work with the regulators and others in the scientific community to see how they can be implemented,” he adds.

Petelle says for data-rich compounds, such as pesticides, the report suggests there may be other approaches that would be less costly, faster or more predictive than the current set of animal tests being used now. “If that’s the case, those are goals that obviously we would support too.”

He says the report repeatedly notes that pharmaceuticals and pesticides “are among the chemicals that have quite a bit of data behind them as opposed to most industrial chemicals.”

The pesticide manufacturing industry always stands behind sound science-based decision making, he says.

Regulatory agencies are constantly adopting new studies and new protocols. During the past 20 years, the amount of data required by manufacturers to get regulatory approval for pesticides has grown tremendously, he says, noting currently it can take up to 10 years of research and cost more than $250 million to bring a new active ingredient to market.

Health Canada’s Pest Management Regulatory Agency approached the Council of Canadian Academies, a non-profit group that coordinates expert assessments of public policy, in 2009 to create the panel. The agency asked the panel’s members to examine how diverse scientific approaches might fit into chemical safety assessments.

The council’s report is called Integrating Emerging Technologies into Chemical Safety Assessment. BF