Proposed Special Review Decision PSRD2024-02, Proposed special review decision for iodocarb (3-iodo-2-propynyl butyl carbamate) and its associated end-use products

Pest Management Regulatory Agency
30 October 2024
ISSN: 2561-636 (PDF version)
Catalogue number: H113-30/2024-2E-PDF (PDF version)

Summary

Table of contents

• Proposed special review decision for iodocarb (3-iodo-2-propynyl butyl carbamate) and its associated end‑use products
• Proposed special review decision for iodocarb
• Risk mitigation measures
• Next steps
• Other information

Proposed special review decision for iodocarb (3-iodo-2-propynyl butyl carbamate) and its associated end‑use products

Under the authority of the Pest Control Products Act, pesticides are regulated by Health Canada’s Pest Management Regulatory Agency (PMRA) on behalf of the Minister of Health. The Pest Control Products Act prescribes both the pre-market and post-market assessment (re-evaluations and special reviews) of pesticides to determine the acceptability or continued acceptability of human health and environmental risks, and acceptable value of a pesticide in Canada. Unlike a re-evaluation, a special review is triggered only under certain circumstances, as described in section 17 of the Pest Control Products Act, and the intent of a special review is to address specifically the identified aspect(s) of concern. The special review approach is described in the PMRA Guidance Document: Approach to Special Reviews of Pesticides.

Health Canada evaluates the aspect(s) of concern that prompted the special review in accordance with subsection 18(4) of the Pest Control Products Act. The internationally accepted science-based approach is used for the assessment of the aspect(s) of concern, similar to all other scientific assessments (for example, new product registrations, re-evaluations). This step includes both risk (or value, if applicable) assessment and risk management to address the concerns identified. Health Canada’s approach to risk and value assessment as well as risk management is outlined in the Framework for Risk Assessment and Risk Management of Pest Control Products.^{Footnote 1}

Pursuant to subsection 17(1) of the Pest Control Products Act, Health Canada initiated a special review of registered pest control products containing iodocarb (3-iodo-2-propynyl butyl carbamate) used in metalworking fluids. This special review was initiated based on post application exposure information, relating to workers handling iodocarb-treated metalworking fluids and/or involved in maintenance/clean-up activities, submitted under section 12 of the Pest Control Products Act. These section 12 data were required as a result of the re-evaluation of iodocarb (RVD2011-04).^{Footnote 2} The identified aspect of concern is:

• Potential occupational dermal risk to workers exposed to iodocarb-treated metalworking fluids.

During the assessment of the above aspect of concern, additional potential health concerns were identified, which led to the expansion of the scope of this special review as per subsection 17(7) of the Pest Control Products Act. Therefore, the overall aspects of concern for this special review are:

• Potential dermal and inhalation risks of concern for mixers/loaders treating metalworking fluids with iodocarb.
• Potential dermal and inhalation risks of concern for secondary workers (machinists) exposed to iodocarb-treated metalworking fluids.

Pursuant to subsection 18(4) of the Pest Control Products Act, Health Canada has evaluated the aspects of concern within the scope of this special review, which are relevant to human health, for registered pest control products containing iodocarb used in metalworking fluids.

Iodocarb is an antimicrobial used as a material preservative (including paints, adhesives and caulks, paper coating, plastic, textiles, and liquid detergents) and industrial fluids preservative (metalworking fluids). It is also used as a joinery wood preservative and sapstain control chemical. For this special review, currently registered products containing iodocarb that are used as preservatives in metalworking fluids were considered and are listed in Appendix I of PSRD2024-02, Proposed special review decision for iodocarb (3-iodo-2-propynyl butyl carbamate) and its associated end-use products.

This document presents the proposed special review decision for iodocarb, including the proposed amendments (risk mitigation measures) to protection human health, as well as the science evaluation on which the proposed special review decision is based. All products containing iodocarb used in metalworking fluids that are registered in Canada are subject to this proposed special review decision. PSRD2024-02 is subject to a 45-day public consultation period^{Footnote 3} during which the public (including the pesticide manufacturers and stakeholders) may submit written comments and additional information to PMRA Publications. The final special review decision will be published after taking into consideration the comments and information received during the consultation period.

Proposed special review decision for iodocarb

Health Canada, under the authority of the Pest Control Products Act, has conducted an evaluation of available relevant scientific information related to the aspects of concern for human health in accordance with subsection 18(4) of the Pest Control Products Act. Based on the evaluation of the aspects of concern, Health Canada is proposing for public consultation, pursuant to section 28 of the Pest Control Products Act, the continued registration of iodocarb used in metalworking fluids and its associated end-use products registered for sale and use in Canada under section 21 of the Pest Control Products Act.

The evaluation of available relevant scientific information related to the aspects of concern indicated that iodocarb used in metalworking fluids showed acceptable risk when iodocarb is used according to the proposed conditions of registration, which includes new mitigation measures.

The proposed additional mitigation measures are summarized below, and details are outlined in Appendix V of the PSRD2024-02.

Risk mitigation measures

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 proposed label amendments including any revised/updated label statements and/or mitigation measures, as a result of the special review of iodocarb, are summarized below. Refer to Appendix V of the PSRD2024-02 for details.

Human health

To protect workers (mixers/loaders) from exposure when treating metalworking fluids with iodocarb:

• When open pouring products containing iodocarb into metalworking fluid, the proposed maximum amount of iodocarb handled per day is limited to 1.25 kg a.i./person. If handling more than this, a closed transfer (injection) system is required.

To protect secondary workers (machinists) from exposure to iodocarb-treated metalworking fluids:

• A maximum concentration of iodocarb in metalworking fluid of 750 ppm.

Next steps

Health Canada will accept written comments on this proposal up to 45 days from the date of publication of PSRD2024-02. Comments on the proposed decision can be submitted during the consultation period to the PMRA through PMRA Publications, or the Public Engagement Portal (Public Engagement Forms - Consultation Comment). For more information or if you have questions, contact the PMRA’s Pest Management Information Service.

Before making a special review decision on iodocarb under section 21 of the Pest Control Products Act, the comments received during the consultation period will be taken into consideration in preparation of the final special review decision document. A science-based approach will be applied in making a final decision on iodocarb. In accordance with subsection 28(5) of the Pest Control Products Act, Health Canada will then publish a final special review decision document, which will include the decision, the reasons for it, a summary of the comments received on the proposed special review decision during the consultation period, and Health Canada’s response to these comments.

Refer to Appendix I of the PSRD2024-02 for details on specific products impacted by this proposed decision.

Other information

The relevant confidential test data on which the proposed decision is based (see References section of the PSRD2024-02) are available for public inspection, upon application, in Health Canada’s Reading Room. For more information, please contact PMRA’s Pest Management Information Service.

Footnotes