In Canada, pesticides are regulated by Health Canada's Pest Management Regulatory Agency (the "PMRA") on behalf of the Minister of Health and under the authority of the Pest Control Products Act (the "PCPA"). Health Canada announced a further consultation in its ongoing assessment of a group of pesticides known as neonicotinoids. Introduced commercially in the 1990s with a wide variety of uses, this group of pesticides has gained international attention in the last decade and has recently come under closer scrutiny by Canada’s PMRA.

Health Canada routinely re-examines pesticides that are registered in Canada to ensure they continue to meet modern safety standards for human health and the environment. There are two post-registration processes by which the PMRA can undertake these examinations: “re-evaluation” (s.16 of the PCPA) and “special reviews” (s.17 of the PCPA).

A “re-evaluation” of registered pesticides is conducted by Health Canada on a cyclical basis, every 15 years or sooner, to determine whether the use of these products continues to be acceptable according to current standards. During a re-evaluation, PMRA reviews available scientific information on the product before proposing a decision, including information provided by pesticide registrants, other federal or provincial departments and information published in scientific literature.

A “special review” is provided for under the PCPA to determine the continued acceptability of the health and environmental risks of a product and its value. The PCPA requires the PMRA to initiate a “special review” of a registered pest control product when there are reasonable grounds to believe that the health or environmental risks of the product are, or its value is, unacceptable.

In response to the global attention on neonics, in 2012 the PMRA decided to undertake a re‑evaluation of the three key neonicotinoids currently approved for agricultural use in Canada, namely imidacloprid, clothianidin, and thiamethoxam. In addition to the re-evaluation, aquatic environmental special reviews are also underway for clothianidin and thiamethoxam.


i. Aquatic Environmental Re-Evaluation

Amongst other things, in 2012, Health Canada announced its intentions to undertake an environmental assessment of imidacloprid to determine how it interacts with aspects of the environment, including aquatic life such as fish, insects, and other organisms. The proposed re‑evaluation decision for imidacloprid was published on November 23, 2016. This assessment concluded that, in aquatic environments in Canada, imidacloprid is being measured at levels that are harmful to certain aquatic insects, which act as a food source for fish, birds and other animals.

The aquatic environmental assessment resulted in a recommendation of a phase-out of imidacloprid over the next three to five years for all agricultural and a majority of other outdoor uses, having determined that, under current conditions of use, the environmental risks for most products containing imidacloprid do not meet current safety standards.

A human health risk assessment was included in the re-evaluation and found no human health concerns from any exposure routes, when used according to the applicable labels. Risks to bees and other pollinators were not a part of this re-evaluation, but instead the PMRA initiated a separate risk assessment specific to pollinators.

ii. Pollinator Re-Evaluation

Health Canada then conducted a re-evaluation of all agricultural, turf and ornamental uses for imidacloprid and its associated end-use products, specifically to assess the risk to pollinators. The risk assessment consisted of characterizing the exposure and effects of imidacloprid to bees, and determining whether exposures resulting from its uses are expected to pose a risk.

The evaluation was conducted according to the Guidance for Assessing Pesticide Risks to Bees, which was collectively developed by the PMRA, the United States Environmental Protection Agency (USEPA) and the California Department of Pesticide Regulation. A preliminary pollinator risk assessment was published in January 2016 that did not point to unacceptable risks to managed honey bees provided strict precautions to limit exposure were followed.

Further data was submitted to the PMRA by the registrants of the products containing imidacloprid and the PMRA reviewed additional available information from open scientific literature. On May 31, 2018, the Proposed Re-evaluation Decision PRVD2018-12 was released and presented the proposed regulatory decision, including suggested risk mitigation measures to further protect pollinators. Based on its scientific evaluation, Health Canada proposed: (i) to phase out certain uses of imidacloprid; (ii) to provide direction on when foliar applications may be done; and (iii) to require additional label statements for seed treatment of cereal and legume crops to minimize bee exposure to dust during planting of treated seed.

Health Canada completed this consultation on August 29, 2018. A final decision by Health Canada that will integrate both imidacloprid re-evaluations (i.e., the aquatic environmental assessment and the pollinator assessment) is anticipated in December 2018.

Clothianidin and Thiamethoxam

i. Aquatic Environmental Special Review

During the re-evaluation of imidacloprid, Health Canada identified that clothianidin and thiamethoxam also occurred frequently and at comparable levels to imidacloprid in certain Canadian waterbodies that were exposed to intensive agriculture. Given the similarities these two neonics have to imidacloprid, in November 2016, Health Canada initiated special reviews for clothianidin and thiamethoxam, starting with an environmental assessment in aquatic environments.

On August 15, 2018, Health Canada published its preliminary recommendations on whether to phase out specific uses for these two neonics, having determined, as with imidacloprid that, in aquatic environments in Canada, both clothianidin and thiamethoxam are being measured at concentrations that are harmful to aquatic insects.

In the proposed special review decisions, Health Canada is proposing to phase-out—over the next three to five years—all outdoor uses of both neonics on food and feed crops, including seed treatments, and on turf (for clothianidin) and outdoor ornamentals (for thiamethoxam). The PMRA will consider alternate risk management proposals, provided that they can achieve acceptable levels in the environment within the same timeframe.

The proposed special review decisions are currently open for public consultation from August 15, 2018, to November 13, 2018. The PMRA has indicated that, once it considers the comments and any information received during the public consultation period, it will publish a final decision.

ii. Pollinator Re-Evaluation

Health Canada conducted a re-evaluation of all agricultural and ornamental uses for thiamethoxam and clothianidin (and their associated end-use products), specifically to assess the risk to pollinators. On December 19, 2017, it published the Proposed Re-evaluation Decision for both neonics.[AK23] Based on its review, the PMRA concluded that an application of pesticides containing both neonics can lead to effects that may impact the survival of bee colonies or solitary bee species and, as such, it is proposing a phase out of certain applications for a variety of crops for both products. The final decisions are expected to be published in late 2018.


Canada is not alone in scrutinizing neonicotinoids. Governments worldwide are taking significant regulatory action, including a registration review by the USEPA for imidacloprid, clothianidin and thiamethoxam. In Europe, the European Food Safety Authority (EFSA) published an updated risk assessment for all three neonics in February 2018 and concluded that overall, neonics represent a risk to bees. Based on this risk assessment, in April 2018, Member States of the European Union endorsed the European Commission’s proposals to ban all outdoor uses of imidacloprid, thiamethoxam, and clothianidin. In Ontario, which enacted strict regulations in July 2015 to regulate the sale and use of treated seeds, the Grain Farmers of Ontario have recently called for a lifting of the regulations in light of the uncertainty surrounding future or continued registration of neonicotinoids in Canada.

We will continue to monitor the PMRA processes and anticipate learning in December 2018 what new regulatory measures Canada will adopt.