Re-evaluation Note REV2014-02, Re-evaluation Project Plan for Prosulfuron

Pest Management Regulatory Agency
22 May 2014
ISSN: 1925-0649 (PDF version)
Catalogue number: H113-5/2014-2E-PDF (PDF version)


In Canada, prosulfuron is under re-evaluation by Health Canada's Pest Management Regulatory Agency (PMRA). The PMRA's pesticide re-evaluation program considers potential risks as well as the value of pesticide products to ensure they continue to meet standards of modern science and current policy established to protect human health and the environment. Under the authority of Section 16 of the  Pest Control Products Act, the registrant of prosulfuron was notified of the initiation of the re-evaluation of prosulfuron. Following this, the registrant of prosulfuron technical grade active ingredient in Canada indicated their intention to support all uses included on the labels of commercial products in Canada. This Re-evaluation Note outlines a project plan and timeline for review, as well as summarizes the anticipated areas of focus related to the re-evaluation of prosulfuron.

Prosulfuron is a selective, postemergent herbicide that has been registered in Canada since 1998. Prosulfuron is currently registered to control broadleaved weeds in field corn, seed corn, winter wheat, sorghum and millet (Use-Site Categories 13 and14). The registered prosulfuron end-use product is formulated as wettable granules packaged into water soluble bags and applied by ground spray equipment.

The project plan discussed below outlines the anticipated areas of focus and risk assessments required to complete the re-evaluation of prosulfuron. Should additional information become available during the re-evaluation period that affects the regulatory status of prosulfuron, the Agency will reconsider the areas of focus and risk assessments required. Currently, a proposed re-evaluation decision for prosulfuron is anticipated to be published for consultation in 2014.

Re-evaluation Project Plan

Human Health Risk Assessment

The toxicology database for prosulfuron was considered complete at the time of initial registration and no major updates have been made since then. Verification of the points of departure and uncertainty factors used for risk assessment will be undertaken and areas not addressed in the original evaluation (for example, establishment of an acute reference dose, dermal and acute dietary endpoints, application of the Pest Control Products Act factor) will be reviewed.

Dietary exposure and risk assessments previously conducted to support currently registered uses will be verified to ensure they meet current science standards and policies. This includes the incorporation of revisions to toxicological reference doses, if applicable; drinking water estimated environmental concentrations; and assessment of the acute dietary risk.

The occupational exposure and risk assessments will be revised to reflect the currently available scientific data and approaches, as well as revised toxicological points of departure, if applicable.

Environmental Risk Assessment

Environmental assessments previously conducted will be verified to ensure they meet current science standards and policies. This includes the incorporation of updated estimated environmental concentrations for risk assessment purposes.

Environmental risk mitigation measures will be reviewed to ensure consistency with current label requirements.

Buffer zones for the protection of sensitive terrestrial and aquatic habitats will be calculated based on current practices and taking into consideration currently registered uses.

The  Toxic Substances Management Policy will be taken into consideration.


The value of prosulfuron will be considered. The viability of alternatives will be examined if risks of concern are identified.

Data Requirements

No additional data requirements have been identified for prosulfuron at this time.

Anticipated Timeline for Re-evaluation

A proposed re-evaluation decision for prosulfuron is anticipated to be published for consultation in 2014.

Additional Information

PMRA documents can be found on the Pesticides and Pest Management portion of Health Canada's website. PMRA documents are also available through the Pest Management Information Service. Phone: 1-800-267-6315 within Canada or 1-613-736-3799 outside Canada (long distance charges apply); fax: 613-736-3798; e-mail.

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