Re-evaluation Decision RVD2019-04, Thiamethoxam and Its Associated End-use Products: Pollinator Re-evaluation

Pest Management Regulatory Agency
11 April 2019
ISSN: 1925-0886 (PDF version)
Catalogue number: H113-9/2019-4E-PDF (PDF version)

Table of Contents

• Re-evaluation Decision
• Outcome of Science Evaluation
• Regulatory Decision for Thiamethoxam
• Next Steps
• Other Information
• Appendix I Registered Thiamethoxam Products in Canada Subject to This Re-evaluation

Re-evaluation Decision

Under the authority of the Pest Control Products Act, Health Canada’s Pest Management Regulatory Agency (PMRA) conducted a re-evaluation of all agricultural and ornamental uses for thiamethoxam and its associated end-use products, specifically to assess the risk to pollinators, such as honey bees, bumble bees, and solitary bees. This re-evaluation assessed the potential risk to pollinators in light of international updates to the pollinator risk assessment framework. Extensive information obtained from published literature, as well as data received from registrants, was considered. Health Canada applied internationally accepted risk assessment methods as well as current risk management approaches and policies. In addition to the pollinator risk assessment, the value of the active ingredient to the various use sectors was assessed.

Products containing thiamethoxam are sold as sprays to be applied to plants and to bare soil. Thiamethoxam is also used as a coating on crop seeds to prevent insects from eating the seeds when they are planted in the ground and to protect the plants grown from treated seeds. Some uses result in thiamethoxam being taken up by the plants from the soil or through their leaves, where it then moves into parts of the flower where nectar and pollen are produced. Because bees use nectar and pollen as their primary sources of food, bees may be exposed to thiamethoxam (and its breakdown products) when they visit certain flowers to collect pollen and nectar. Bees may also be accidentally sprayed or collect water containing thiamethoxam. Currently registered products containing thiamethoxam that are subject to this re-evaluation are listed in Appendix I.

This document (RVD2019-04, Thiamethoxam and Its Associated End-use Products: Pollinator Re-evaluation) presents the final regulatory decision^{Footnote 1} for the pollinator re-evaluation of thiamethoxam, including the required risk mitigation measures to protect bees. Most products containing thiamethoxam are subject to this regulatory decision. The proposed regulatory decision published in PRVD2017-24, Thiamethoxam and Its Associated End-use Products: Pollinator Re-evaluation,^{Footnote 2} has undergone a 90-day consultation that ended on 19 March 2018.

Health Canada received comments mostly relating to the value and pollinator risk assessments. These comments are summarized in Appendix II of RVD2019-04, Thiamethoxam and Its Associated End-use Products: Pollinator Re-evaluation, along with the responses by Health Canada. The comments did not result in a change to the risk assessments. Therefore, this decision is consistent with the proposed re-evaluation decision stated in PRVD2017-24. All of the data that were used as the basis for the proposed re-evaluation decision are published in PRVD2017-24. Further data used in the final re-evaluation decision, including data received during the consultation period, are listed in Appendix IV of RVD2019-04.

Outcome of Science Evaluation

The risk assessment, conducted according to the Guidance for Assessing Pesticide Risks to Bees,^{Footnote 3} determined that there are varying degrees of effects on bees. Some current uses of thiamethoxam are not expected to affect bees. For some uses, mitigation measures (in other words, changes to the conditions of registration) are required to minimize potential exposure to bees. Mitigation measures include changes to the use pattern and label improvements. When thiamethoxam is used in accordance with these new risk reduction measures, the reduced environmental exposure is considered adequate and risks are acceptable. Label statements informing users of the potential for toxicity to pollinators are required on product labels. For other uses, risks to pollinators were not found to be acceptable; therefore, these uses are cancelled.

Regulatory Decision for Thiamethoxam

Health Canada has completed the pollinator re-evaluation of thiamethoxam. Under the authority of the Pest Control Products Act, Health Canada has determined that, with required amendments, continued registration of products containing thiamethoxam is acceptable; however, certain uses of thiamethoxam are cancelled to address potential risks of concern to pollinators. An evaluation of available scientific information found that some uses of thiamethoxam products meet current standards for protection of pollinators when used according to the conditions of registration, which include required amendments to label directions. Label amendments, as summarized below and listed in Appendix III of RVD2019-04, are required for all end-use products. No additional data are requested.

Risk Mitigation Measures to Protect Pollinators

Registered pesticide product labels include specific directions for use. Directions include risk mitigation measures to protect human health and the environment and must be followed by law. As a result of this re-evaluation of thiamethoxam, further risk mitigation measures for product labels are required.

Certain crops are highly attractive to bees when their flowers are in bloom. Since large numbers of bees are attracted to these crops when they are in bloom and based on an assessment of the risks to bees, the application of pesticides containing thiamethoxam can lead to effects that may have an impact on the survival of bee colonies or solitary bee species.

In order to protect pollinators, Health Canada is cancelling the following uses of thiamethoxam:

• Foliar and soil application to ornamental crops that will result in pollinator exposure (in other words, are planted outdoors and are attractive to pollinators)
• Soil application to berry crops, cucurbit crops and fruiting vegetables, and
• Foliar application to orchard trees.

Due to the attractiveness of some crops to bees and based on an assessment of the risks to bees, application of pesticides containing thiamethoxam before and during crop flowering can lead to effects that may have an impact on the survival of bee colonies or solitary bee species.

In order to protect pollinators, Health Canada is changing the timing of application for the following uses of thiamethoxam

The following crops cannot be sprayed before or during bloom:

• Foliar application to legume and outdoor fruiting vegetables, and
• Foliar application to berry crops (with renovation required for woody berries).

The following crops cannot be sprayed during bloom:

• Foliar application to sweet potato and potato

To minimize bee exposure to dust during planting of treated seed, additional label statements are required for the following use:

• Seed treatment of cereal and legume crops.

The additional risk mitigation measures described above will be implemented over a 24-month period. The risks identified are not considered imminent because they are not expected to cause irreversible harm over this period. Potential effects include sublethal effects on colonies or solitary bees, but affected pollinator populations are expected to recover following implementation of the additional restrictions which will reduce exposure. Moreover, recovery is expected because risks to pollinators are geographically limited to areas where these products are applied and areas adjacent to application sites. The presence of unaffected solitary bees, bumble bees, and honey bees in areas where products are not being used will further facilitate recovery since unaffected bees in the environment can move back into areas where effects may have occurred. Overall, risk to pollinators is acceptable over the time period required to implement the mitigation measures.

As a result of this decision, growers will be required to change their pest management practices. Pesticides have extensive and precise instructions and often require specialized application and safety equipment and training. This transition period will allow for an orderly and safe implementation of these new restrictions, and should reduce the risk of product misuse or the improper disposal of products as users switch to alternatives, where required. This approach is consistent with Health Canada’s current policy and practice with respect to phase out of uses as a result of a re-evaluation (Regulatory Directive DIR2018-01, Policy on Cancellations and Amendments Following Re-evaluation and Special Review) and with the practice of other international regulators.

A small subset of uses were found to lack alternatives for the management of certain serious pests (the invasive brown marmorated stink bug and certain weevils) on a very few crops present in limited geographical areas of Canada. As a result, the implementation of the re-evaluation decision for these uses will be delayed for an additional year to allow growers to find pest management solutions. During this period, the overall exposure to pollinators will be significantly reduced through both removal of uses to control other pests on these crops and other crops that pose a risk to bees, as well as through implementation of additional restrictions in application timing which will further reduce pollinator exposure. The risks to pollinators are therefore considered acceptable for an additional year for this small subset of uses.

Next Steps

To comply with this decision, taking into account Regulatory Directive DIR2018-01, Policy on Cancellations and Amendments Following Re-evaluation and Special Review, the required mitigation measures must be implemented on all product labels sold by registrants no later than 24 months after the publication date of this decision document. Appendix I lists the products containing thiamethoxam that are registered under the authority of the Pest Control Products Act.

Other Information

Any person may file a notice of objection^{Footnote 4} regarding this decision on thiamethoxam within 60 days from the date of publication of this Re-evaluation Decision. For more information regarding the basis for objecting (which must be based on scientific grounds), please refer to the Pesticides section of the Canada.ca website (Request a Reconsideration of Decision) or contact the PMRA’s Pest Management Information Service.

Appendix I Registered Thiamethoxam Products in Canada Subject to This Re-evaluation

Table 1 Registered Thiamethoxam Products in Canada Subject to This Re-evaluation as of 2 October 2018, excluding discontinued products and products with a submission to discontinue

Registration Number	Marketing Class	Registrant	Product Name	Formulation Type	Guarantee
26665	Technical	Syngenta Canada Inc.	Thiamethoxam Technical	Dust or powder (solid)	99.1%
26637	Commercial	Syngenta Canada Inc.	Helix Liquid Seed Treatment	Suspension	Thiamethoxam 10.3%; metalaxyl-M and S isomer 0.39%; fludioxonil 0.13%; difenoconazole 1.24%
27045			Cruiser 5FS Seed Treatment		Thiamethoxam 47.6%
27986			Cruiser 350FS Seed Treatment Insecticide		Thiamethoxam 29.9%
28407			Actara 240SC Insecticide		Thiamethoxam 240 g/L
28408			Actara 25WG Insecticide	Wettable granules	Thiamethoxam 25.0%
28821			Cruiser Maxx Beans Seed Treatment	Suspension	Thiamethoxam 22.6%; metalaxyl-M and S isomer 1.70%; fludioxonil 1.12%
29127			Cruiser Maxx Cereals Commercial Seed Treatment		Thiamethoxam 2.8%; metalaxyl-M and S isomer 0. 56%; difenoconazole 3.36%
29192			Cruiser Maxx Cereals Seed Treatment		Thiamethoxam 2.8%; metalaxyl-M and S isomer 0. 56%; difenoconazole 3.36%
30388			A18046A Seed Treatment		Thiamethoxam 261 g/L; metalaxyl-M and S isomer 19.7 g/L; fludioxonil 12.9 g/L; azoxystrobin 10.4g/L
30404			Endigo Insecticide		Thiamethoxam 141 g/L; lambda-cyhalothrin 106 g/L
30436			Cruiser Maxx Vibrance Cereals Seed Treatment		Thiamethoxam 30.7 g/L; sedaxane 8.0 g/L; metalaxyl-M and S isomer 9.5 g/L; difenoconazole 36.9 g/L
30723			Flagship Insecticide	Wettable granules	Thiamethoxam 25%
30900			Minecto Duo 40WG	Wettable granules	Thiamethoxam 20%; cyantraniliprole 20%
30901			Mainspring X Insecticide		Thiamethoxam 20%; cyantraniliprole 20%
31024			Cruiser Maxx Potato Extreme	Suspension	Thiamethoxam 250 g/L; fludioxonil 62.5 g/L; difenoconazole 123 g/L
31453			Cruiser Vibrance Quattro		Thiamethoxam 61.5 g/L Difenoconazole 36.9 g/L Metalaxyl-M and S-Isomer 9.2 g/L Sedaxane 15.4 g/L Fludioxonil 7.7 g/L
31454			Helix Vibrance		Thiamethoxam 269 g/L Difenoconazole 16 g/L Metalaxyl-M and S-Isomer 5 g/L Sedaxane 3.4 g/L Fludioxonil 1.7 g/L