Most countries regulate the residue levels of crop protection products that can be found in fresh and processed food products. The same is true in Canada.

The regulations around these residues are set by the Pest Management Regulatory Agency (PMRA). Before registering a product for food use in Canada, the PMRA must determine the quantity of residues that are likely to remain in or on the food item when a product is used according to label directions and that such residues will not be of concern to human health. This quantity, typically in parts per million (ppm), is then legally established in Canada as a maximum residue limit (MRL). Foods of both domestic and imported origin are then considered to be adulterated or contaminated if they contain residues in excess of the specified MRL – food in violation of this level can then be removed from the marketplace.

An MRL does not imply a toxicological safety threshold, but rather the maximum acceptable level of residue that is legally allowed on foods, based on approved product use. The PMRA sets science-based MRLs at levels well below the amount that could pose a health concern to ensure the food that Canadians eat is safe. An established MRL applies to the raw food commodity as well as to any processed food made from that commodity, unless separate MRLs have been developed. Across the world, MRLs can be set by individual countries, established across regions such as the European Union, or even developed globally through Codex Alimentarius – a Food and Agriculture Organization of the United Nations initiative.

Though Canada is not unique in having MRLs, we have retained an archaic policy for cases where the PMRA has not previously established or has subsequently revoked a specific MRL for Canada. This policy is referred to as the general maximum residue limit (GMRL) or default MRL. The GMRL applies where no Canadian MRL exists and allows the sale of foods with residues of any crop protection material up to 0.1 ppm.

When the GMRL was established in the 1970s, the analytical methods at the time were not sensitive enough to accurately detect most residues below 0.1 ppm. Therefore, 0.1 ppm was a practical limit based on the capabilities of the day. Technology has since sufficiently advanced that residues can often be reliably detected below 0.01 ppm. Nearly all countries that still do employ a GMRL have now set a limit of 0.01 ppm or 10 per cent of the Canadian limit. Only New Zealand still retains a GMRL of 0.1 ppm. Many other countries also simply avoid having a GMRL altogether, including Australia and the United States, and choose instead to establish their own specific MRLs for all approved active ingredients.

Why should a GMRL that is ten times the global standard matter to Canadians? Firstly, it means that for crop protection products never before registered in Canada, foreign producers using these products simply have an easier bar to meet for Canadian market access compared to many other countries. Secondly, when an active ingredient that was registered for use in Canada is cancelled by PMRA, often so are any specific Canadian MRLs, and it returns by default to the GMRL value. At a level of 0.1 ppm, it can often allow foreign producers to continue some use of a product prohibited in Canada by PMRA and still meet the MRL requirements for import. This applies no matter if a product is cancelled in Canada for human health or environmental reasons. 

For example, if mancozeb – currently under review by PMRA – wasto be completely cancelled in Canada, PMRA would also likely cancel all established Canadian MRLs. Any food products could then still legally contain mancozeb residues as long as it did not exceed 0.1 ppm.

A quick scan of the most recently published Canadian Food Inspection Agency’s (CFIA) National Chemical Residue Monitoring Program (NCRMP), which tests domestic and foreign food sources for crop protection residues, found that in 2014-2015, there were multiple imported sources of apple, apricot, artichoke, asparagus, and avocado with positive mancozeb residues that did not exceed 0.1 ppm and thus would be legally allowable in Canada under the GMRL. And that’s just the foods starting with ‘A’! Therefore, if PMRA banned mancozeb use in Canada, foreign growers would certainly be able to continue some use on their export crops to Canada yet the same product would not be allowable for Canadian growers. This is not in our best interest!

The flaws in Canada’s GMRL policy were identified by PMRA in two documents published by the agency in 2003 and 2006. It was recognized that the default level of 0.1 ppm was not only highly unusual in the global context but also allows higher residues than necessary in some cases, permits importation of foods containing certain residues which PMRA has not reviewed for safety, and also could lead to overestimates of dietary exposure to crop protection products.

It was proposed in these documents that the GMRL be revoked and replaced with specific MRLs for each food and active ingredient combination, as is the case with many other countries around the world. Yet despite progress on setting specific MRLs, more than a decade later we still have the 0.1 ppm GMRL policy in place. It’s time for Canada to catch up with the world and end this very unusual policy, eliminate this unfair advantage for foreign competitors, and level the playing field for Canadian growers!