New Label Requirements for Soil Fumigant Products Containing Chloropicrin, Dazomet, Metam Sodium or Metam Potassium

Health Canada's Pest Management Regulatory Agency (PMRA) is requiring label improvements that will affect the use of soil fumigants containing the active ingredients chloropicrin, dazomet, metam sodium and metam potassium. These label improvements are specified in Re-evaluation Notes for each of these active ingredients, which were published on 14 September, 2012.

The label improvements are intended to further limit user exposure and to increase the protection of bystanders and the environment, in light of the inherent toxicity and irritant properties of the active ingredients and the potential for exposure. The re-evaluation decision consists of label improvements only. No soil fumigant uses or products are being lost as a result of this re-evaluation decision. These label improvements are consistent with measures being placed on soil fumigants by the United States Environmental Protection Agency (USEPA).

Proposed label improvements for the soil fumigant cluster were first presented for public consultation in Re-Evaluation Notes on August 13, 2010: Soil Fumigants Proposed Mitigation Measures (REV2010-10), Chloropicrin - Proposed Mitigation Measures (REV2010-12), Dazomet - Proposed Mitigation Measures (REV2010-13), and Metam Sodium and Metam Potassium - Proposed Mitigation Measures (REV2010-09). Comments received during consultation resulted in some changes to the proposed label improvements.

The label improvements apply to all soil fumigant uses and all application methods. Products containing these active ingredients are registered in Canada as pre-plant soil fumigants for use on a variety of terrestrial and/or greenhouse food/feed and non-food/non-feed crops, forests/woodlots, ornamentals, nurseries, seed beds and/or turf. The fumigants are applied and incorporated into the soil; treated soil is then sealed and subsequently aerated prior to planting.

Major new requirements include:

• A Fumigation Management Plan (FMP) for all soil fumigant applications: A written FMP must be developed prior to the start of any application. The plan will cover key steps to help ensure a safe and effective fumigation, including monitoring of site conditions (soil, air, weather, etc.), calculation and posting of buffer zones, and emergency response planning.
• Instructions for mandatory Good Agricultural Practices (GAPs): GAPs are application practices that improve the safety and efficacy of soil fumigation operations. These include monitoring of weather conditions (to identify conditions that are unfavourable for soil fumigation), soil preparation, monitoring of soil temperature and moisture, and proper soil sealing.
• Restrictions for workers re-entering treated areas: Only fumigant handlers (i.e. workers involved in soil fumigant applications) are allowed into the treated area following application. The duration of the restriction is determined by the application methodology.
• Respiratory protection for handlers and stop work triggers: If sensory irritation (e.g. tearing, burning of the eyes or nose) is experienced or if specific fumigant air concentrations are reached, handlers are required to wear respiratory protection or leave the treated area.
• Buffer zones for all soil fumigant applications: A buffer zone is an area established around the perimeter of the treated area where entry by anyone other than fumigant handlers is prohibited. Buffer zone distances are determined using look-up tables outlined on product labels and are based on factors such as the application rate, the treated area and the application method.
• Monitoring of fumigation sites or information for neighbours: Either monitoring of fumigation sites for sensory irritation, or the distribution of information to neighbours of treated areas, is required for fumigant applications where: (1) a buffer zone of a distance greater than eight meters is required, and (2) residences or businesses are located in proximity to the edge of the buffer zone.

Chemical-specific label improvements are required for all registered uses. Please refer to the Re-evaluation Notes for chloropicrin (REV2012-09), dazomet (REV2012-10), and metam sodium/metam potassium (REV2012-11) for a full description of the required amendments.

Manufacturers have up to 24 months to have the new labelling in place.

For more information, please contact the Pest Management Information Service at 1-800-267-6315, or visit the Pesticides and Pest Management section of Health Canada's web site at healthcanada.gc.ca/pmra.