Q: Maximum residue limits: what are they and why are they important?
A: In the agricultural industry, we hear the term maximum residue limit (MRL) referred to on numerous occasions. The term refers to the maximum amount of pesticide residue expected to remain in food products when a crop protection product is used according to label directions.
Prior to the registration of a pesticide, Health Canada determines maximum residue limits as part of the assessment process. Using science-based MRLs, Health Canada sets these limits to ensure the food Canadians eat is safe. MRLs are set at levels well below the amount that could pose a health concern for each pesticide-crop combination. A product will not be permitted for sale or use in Canada if an unacceptable risk is determined. If a product or food tested exceeds these MRLs, the Canadian Food Inspection Agency takes enforcement actions.
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Why are maximum residue limits important? The trade of Canadian agricultural goods relies on compliance with maximum residue limits. The countries that Canada exports products to also set their own maximum residue limits. Canadian exports must comply with the importing countries’ MRLs for successful trade.
What does this mean for growers? Growers play a vital role in protecting the integrity of their crops and helping to maintain Canada’s reputation as a world-class agricultural food exporter.
To keep residues within acceptable limits, growers and advisers must continue to use good management practices. This includes following the label recommendations for rate and timing of application. Pay close attention to pre-harvest intervals for the product you are using, whether it be desiccants, late-season fungicide or insecticide applications.
As we near the end of the growing season, producers will be faced with increased pressure to get their crops off the field and into the bin. While growers may sometimes be tempted to use a product on a crop that is not registered to aid in dry-down rates, this temptation must be avoided. Using a product on a crop that is not registered could cause major trade consequences and the producer could be held responsible.
Candice Robinson, B.Sc., CCA, is a manager of agronomic services for Nutrien Ag Solutions in southeast Saskatchewan.