Full report: Office of the Auditor General of Canada re Pesticide Safety

Download full report here


Neonicotinoid insecticides are widely used around the world. When applied to seeds before planting, they render the plant toxic to insects. These pesticides have been used in Canada since 1995 on corn, canola, soybeans, and other crops.

Growing market reliance. Currently, 36 of Canada’s 80 conditionally registered pest control products are neonicotinoids. Between 2008 and 2015, the number of conditionally registered neonicotinoid pest control products increased by 80 percent (from 20 products to 36). The growth of these products in number and sales suggests that the market has become increasingly reliant on them.

Potential risks. Neonicotinoids are now widely suspected of causing significant ecological harm. Much of the concern has focused on their potential negative effects on bees. Recent studies indicate that neonicotinoids have broader effects on ecosystems—involving, for example, birds, earthworms, other pollinators, and aquatic invertebrates.

Value questioned. The US Environmental Protection Agency recently concluded that these seed treatments provide negligible overall benefits to soybean production in most situations. In Canada, a draft study by the Pest Management Regulatory Agency (the Agency) indicated that the lost yield from a ban on neonicotinoids would have a relatively small economic cost in proportion to the overall value of corn and soybean crops.

The Agency’s actions. In 2003, the Pest Management Regulatory Agency determined that studies of the chronic toxicity of clothianidin (a neonicotinoid) to honeybee hives were required by 2008 as a condition of registration. The Agency later identified the absence of these studies as a “critical data gap.” More than a decade after granting the conditional registration, the Agency had still not confirmed its risk assessment. Despite this, the Agency continued to grant conditional registrations for clothianidin and other neonicotinoid products.

In June 2012, the Agency initiated re-evaluations of agricultural uses of neonicotinoid pesticides in collaboration with the US Environmental Protection Agency. The re-evaluations are expected to be completed in 2017 or 2018.

Mitigation measures. In the interim, the Pest Management Regulatory Agency implemented several measures for the corn and soybean planting seasons in 2014 and 2015, including the use of dust-reducing seed planting practices and new product labels with enhanced warning statements.

1.20The Agency’s response to unfulfilled conditions of registration. We also found that the Agency had never exercised its authority to cancel a conditional registration when registrants failed to fulfill the conditions of registration. There appeared to be no consequences for registrants that did not meet the conditions.

1.21Recommendation. The Pest Management Regulatory Agency should ensure that registrants respect the timelines specified in conditional registrations for providing required information. It should also assess the data within its established two-year timeline to determine the continued acceptability of pest control products and active ingredients.

Re-evaluations of pesticides

1.22Overall, we found that the Pest Management Regulatory Agency (the Agency) did not manage an important aspect of its re-evaluations of pesticides according to the Pest Control Products Act. Although the Agency considered the value of pesticides and their health and environmental risks, it did not assess their cumulative effects on human health when required by the Act. In addition, the Agency had made insufficient progress in completing the re-evaluations of older pesticides.

1.23These findings are important because the Agency must apply the latest available scientific knowledge and data to its re-evaluations to confirm that the health and environmental risks of older pesticides remain within acceptable limits. If the Agency does not consider the cumulative health effects of pesticides in its re-evaluations, it lacks potentially important information about risks and how they should be managed. The Agency’s slowness in completing risk assessments may cause product labels and mitigation measures to become outdated, and pesticides remaining on the market may no longer meet current standards. Such situations could expose users and the environment to unacceptable risks.