Special Review Decision SRD2021-03, Special Review Decision: Clothianidin Risk to Aquatic Invertebrates

Pest Management Regulatory Agency
31 March 2021
ISSN: 2561-6269 (PDF version)
Catalogue number: H113-17/2021-3E-PDF (PDF version)

Summary

Table of contents

• Special review decision
• Outcome of science evaluation
• Regulatory decision for clothianidin
• Risk mitigation measures to protect aquatic invertebrates
• Next steps
• Other information
• Appendix I Registered products containing clothianidin in Canada that are subject to this special review decision
• Appendix II Registered commercial class uses of clothianidin in Canada as of 31 July 2020 that are subject to this special review

Special review decision

Pursuant to subsection 17(1) of the Pest Control Products Act, Health Canada’s Pest Management Regulatory Agency (PMRA) conducted a special review of all agricultural and turf uses for registered pest control products containing clothianidin. The decision to conduct the special review was based on a preliminary analysis of available information on the concentration and frequency of detections of clothianidin in the aquatic environment. The aspect of concern for this review is to assess potential risk to aquatic invertebrates exposed to clothianidin applied as a seed, foliar or soil treatment.

Health Canada evaluated the aspect of concern that prompted the special review in accordance with subsection 18(4) of the Pest Control Products Act. The proposed special review decision was published for consultation in Proposed Special Review Decision (PSRD2018-01), Special Review of Clothianidin Risk to Aquatic Invertebrates: Proposed Decision for Consultation.^{Footnote 1} Since the publication of PSRD2018-01 on 15 August 2018, a significant number of comments were received during the consultation period. In addition, extensive information obtained from published literature, as well as data received from registrants and environmental monitoring networks^{Footnote 2} was also considered.

In addition, during the consultation period, Health Canada issued a final re-evaluation decision examining the effects of clothianidin on pollinators Re-evaluation Decision RVD2019-05, Clothianidin and Its Associated End-use Products: Pollinator Re-evaluation. Final Decision. This special review decision takes into consideration the additional mitigation measures put in place as a result of the pollinator re-evaluation. Health Canada has completed the special review for clothianidin, and this final special review decision has resulted in changes to the proposed regulatory decision as described in PSRD2018-01.

A reference list of information used as the basis for the proposed special review decision is included in PSRD2018-01. Further information used in the special review decision is listed in Appendix IX of Special Review Decision: Clothianidin Risk to Aquatic Invertebrates (SRD2021-03). Therefore, the complete reference list of all information used in this final special review decision includes both the information set out in the list of references of the PSRD2018-01 and the information set out in Appendix IX of SRD2021-03.

This document presents the final regulatory decision^{Footnote 3} for the special review of clothianidin, including the required risk mitigation measures to protect aquatic invertebrates. All pest control products containing clothianidin that are registered in Canada for agricultural and turf uses are subject to this special review decision (see Appendix I). Appendix II lists all of the registered uses of Commercial Class end-use products containing clothianidin that were subject to this special review, taking into consideration the required use restrictions identified in RVD2019-05. Appendix III of SRD2021-03 summarizes the comments received during the consultation period and provides Health Canada’s responses to these comments. All of the data that were used as the basis for the proposed special review decision are published in PSRD2018-01. Additional data used in the final special review decision, including data received during the consultation period, are listed in Appendix IV of SRD2021-03 for toxicity information and in Appendix VII of SRD2021-03 for monitoring information.

Under the authority of the Pest Control Products Act, Health Canada has determined that continued registration of products containing clothianidin is acceptable with additional risk mitigation measures (that is, with changes to the conditions of registration). An evaluation of available scientific information found that uses of clothianidin products meet current standards for protection of the environment when used according to revised label directions, which include mitigation measures. Label amendments, as summarized below and listed in Appendix VIII of SRD2021-03, are required.

Outcome of science evaluation

The environmental risk assessment took into consideration revisions to clothianidin uses as outlined in RVD2019-05, scientific comments received on study interpretations during consultation of PSRD2018-01, newly published relevant toxicity data and additional water monitoring data. Based on these data it was determined that the risks to aquatic invertebrates resulting from chronic exposure following application of clothianidin under certain currently registered conditions are acceptable. For uses where the risks were not shown to be acceptable, mitigation measures are required to minimize exposure to aquatic invertebrates which include changes to the use pattern or cancellation in cases when the mitigation options were not considered viable. In addition to the prescribed mitigation measures, label amendments including the addition of best management practices and label statements informing users of the toxicity to aquatic organisms are required.

Regulatory decision for clothianidin

Health Canada has completed the special review of clothianidin’s risk to aquatic invertebrates. Following an evaluation of the aspect of concern, under the authority of the Pest Control Products Act, Health Canada has determined that, with additional risk mitigation measures, continued registration of products containing clothianidin is acceptable. An evaluation of available scientific information found that some uses of clothianidin products meet current standards for protection of aquatic invertebrate communities when used according to the revised conditions of registration, which include required amendments to label directions. Label amendments, as summarized below and listed in Appendix VIII of SRD2021-03, are required for all end-use products. Certain uses of clothianidin are cancelled as risks to aquatic invertebrates were not shown to be acceptable.

Risk mitigation measures to protect aquatic invertebrates

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. The required amendments, including any revised/updated label statements and/or mitigation measures as a result of this special review decision, are summarized below. Refer to Appendix VIII of SRD2021-03 (Label Amendments).

In order to protect aquatic invertebrate communities, Health Canada is cancelling the following uses of clothianidin:

• In-furrow application on potato.
• Seed treatment for field sown leafy vegetables and bunching onion. Planting rates for these crops exceed the maximum allowable application rate of 100 g a.i./ha.

Health Canada is changing the conditions of use of clothianidin for the following crops:

• The maximum seed treatment rate for field corn is reduced to 150 g a.i./100 kg seed. This results in the cancellation of the use for corn rootworm. No change is required for popcorn or sweet corn.
• For seed treatment uses on vegetables, the yearly maximum rate per hectare is limited to 100 g a.i./ha. This limits the planting rates used on broccoli, bulb onion, carrot, cabbage, cucumber and leek to meet this yearly maximum rate.
• The maximum foliar rate for use on cucurbits is reduced to a single application of 70 g a.i./ha per season. This results in the cancellation of use for brown marmorated stink bug.
• The maximum foliar rate for use on potatoes is reduced to a single application of 52.5 g a.i./ha per season.
• The maximum foliar rate for use on turf is reduced to a single application of 125 g a.i./ha per season. This results in the cancellation of use for hairy chinch bug, annual bluegrass weevil, bluegrass billbug and European crane fly.
• Cancellation of greenhouse seed treatment use for onion maggot and seed corn maggot on bulb onions, as these are only pests found in field production.
• New or revised spray buffer zones are required for freshwater habitats.

Next steps

To comply with this decision, the required amendments (mitigation measures and label updates) must be implemented on all product labels no later than 24 months after the publication date of this special review decision (SRD2021-03). The risks identified are not considered imminent and serious because they are not expected to cause irreversible harm over this phase-out period. Potential effects include reduced aquatic insect abundance. Affected populations have the potential to recover following implementation of the additional restrictions which will reduce overall exposure. Accordingly, both registrants and retailers will have up to 24 months from the date of this decision document to transition to selling the product with the newly amended labels.

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).

Similarly, users will also have the same 24-month period from the date of SRD2021-03 to transition to using the newly amended labels, which will be available on the Public Registry.

A small subset of uses were found to lack suitable alternatives for the management of serious pests (the onion maggot and seedcorn maggot) on bunching onion (seed treatment). The effective date of the special review decision for these uses will be delayed for 24 months pursuant to subsection 21(3) of the Pest Control Products Act. The risk to aquatic invertebrates has been determined to be acceptable over this time period because the overall exposure to aquatic invertebrates will be significantly reduced through both removal of uses to control other pests on these crops and other crops posing a risk to aquatic invertebrates. Because of the overall reduction in use, exposure, and risk to aquatic invertebrates, the continued use for 24 additional months for these clothianidin uses with no suitable alternatives is not expected to impact aquatic invertebrate populations, and is considered acceptable.

Refer to Appendix I for details on specific products impacted by this decision.

Other information

Any person may file a notice of objection^{Footnote 4} regarding this decision on clothianidin within 60 days from the date of publication of this special review 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 by phone (1-800-267-6315) or by e-mail (hc.pmra-info-arla.sc@canada.ca).

The relevant confidential test data on which the decision is based (as referenced in PSRD2018-01 and Appendix IX of SRD2021-03) are available for public inspection, upon application, in the PMRA’s Reading Room. For more information, please contact the PMRA’s Pest Management Information Service.

Appendix I Registered products containing clothianidin in Canada that are subject to this special review decision

Appendix II Registered commercial class uses of clothianidin in Canada as of 31 July 2020 that are subject to this special review