Re-evaluation Note REV2021-01, Project Plan for Cumulative Health Risk Assessment – N-Methyl Carbamates

• Pest Management Regulatory Agency
• 1 April 2021
• ISSN: 1925-0649 (PDF version)
• Catalogue number: H113-5/2021-1E-PDF (PDF version)

Table of Contents

• Background
• Re-evaluation project plan
• Additional information

Background

In Canada, an assessment of the cumulative health risks for active ingredients belonging to the N-methyl carbamate (NMC) class of pesticides, as described in Science Policy Note SPN2018-02, Cumulative Health Risk Assessment Framework, is underway.

As outlined in Re-evaluation Note REV2018-17, Initiation of Cumulative Health Risk Assessment – N-Methyl Carbamates, the NMC class of pesticides consists of five technical grade active ingredients registered in Canada, carbaryl, formetanate hydrochloride, methomyl, oxamyl, and propoxur, as well as consideration of six additional pesticides that could be present on imported food commodities. These include carbofuran, aldicarb, pirimicarb, thiodicarb, bendiocarb, and methiocarb.

Under the authority of section 16 of the Pest Control Products Act, the Canadian registrants of NMC pesticides were notified of the initiation of the re-evaluation focusing on the cumulative risk assessment of this class of compounds. Following this, the registrants of NMC technical active ingredients in Canada indicated support for all uses included on the labels of the end-use products in Canada.

The re-evaluation project plan below outlines the timelines, the anticipated areas of focus for the risk assessment, and the data submitted for the cumulative risk assessment of the NMC pesticides.

Re-evaluation project plan

Anticipated re-evaluation timeline

The cumulative risk assessment process for the NMC pesticides is aligned with the process map described in SPN2018-02. The proposed re-evaluation decision for the NMC cumulative health risk assessment is anticipated to be published for consultation by Q1 2023-24.^{Footnote 1} The re-evaluation timeline may be affected if, during the risk assessment, Health Canada identifies additional areas of focus that should be considered.

Areas of focus

REV2018-17 outlined the scoping assessment/problem formulation for the NMC cumulative risk assessment. The scoping assessment identified the available information relating to the evidence of a common mechanism of toxicity, use pattern, and likelihood of co-exposure to the pesticides being considered, and summarized the areas of focus for the NMC cumulative risk assessment. It was concluded that a common mechanism of toxicity for the NMC pesticides exists, and that there is potential for co-exposure to 9 of the 11 NMC pesticides considered. Potential exposure pathways identified included food, drinking water and residential settings, and it was concluded that the oral route would be considered for co-exposure for the majority of the chemicals in the common assessment group, in addition to the dermal and inhalation routes for certain NMC pesticides.

Data submitted

Health Canada required additional data from the registrants of the technical grade active ingredients for the NMC pesticides related to health and environmental fate. Available data have been submitted to Health Canada. A summary of the data call-in can be found in the PMRA's Public Registry.

Additional information

PMRA documents can be found in the Pesticides section of Canada.ca. PMRA documents are also available through the Pest Management Information Service.