On November 6, 2023, the Canadian Federal Court dismissed the applications of Safe Food Matters and Prevent Cancer Now, represented by Ecojustice, for partial annulment of the government decisions of May 13, 2021 and December 21, 2023, authorizing the use of chlorpyrifos-based products until December 10, 2023.

Introduced in Canada in 1969, chlorpyrifos is an organophosphate insecticide developed during the Second World War for its neurotoxic properties. Since the early 2000s, in view of the product's toxicity, the Pest Management Regulatory Agency (PMRA) has been restricting the use and sale of chlorpyrifos-based products. The domestic use of chlorpyrifos was banned in 2000, risk management measures for workers were adopted in 2007 and, in 2019, the PMRA undertook to re-evaluate the registration of chlorpyrifos-based products. In 2020, following this review, many uses, particularly in agriculture, were banned.

In two decisions dated May 13, 2021 and December 21, 2021, the PMRA decided to withdraw all authorizations granted to products containing chlorpyrifos, on the grounds that chlorpyrifos producers had failed to provide the data requested by the PMRA as part of the re-evaluation procedure, but provided for a transitional period of two years during which, in order to run down stocks, the use and distribution of chlorpyrifos would be possible. The PMRA's reasons for this decision include the fact that, given the restrictions in place prior to the ban on chlorpyrifos, use and sales of the substance have declined, that the risks to human health are low, and that no serious accidents have been reported involving exposure to chlorpyrifos in Canada between 2007 and 2021.

In June 2021, the applicant associations asked the Federal Court to examine the reasonableness of the two-year transition period, and to determine whether the Minister of Health had sufficiently taken into account the evidence demonstrating the dangers and potential "unacceptable risks".

The Federal Court declared the appeal against the first decision of May 13, 2021 inadmissible as moot, insofar as it had been replaced by the decision of December 21, 2021. Next, the Court held that the second decision of December 21, 2021 was sufficiently justified, transparent and intelligible, and that it was not for the Court to substitute its assessment of the facts for that of the PRMA, the national expert body on pesticides.

In addition, the Court rejected arguments concerning PRMA's failure to take account of certain risk factors, stressing that they had been adequately taken into account and that PRMA was not obliged to refer to any comments or evidence brought to its attention. According to the Court, the elements taken into account by PRMA in its decision are sufficient to satisfy the requirements of the Pest Control Product Act. The scientific approach and the precautionary principle have been respected. As a result, the two-year transition period has not been cancelled.