Pesticide residues

Pesticide residues in food

Pesticide application to crops and animals may leave residues in or on food when it is sold. Therefore, Health Canada carefully evaluates pesticides before they can be used in Canada and establishes the amount of residues that can be on crops at harvest or animals at slaughter. The levels are called maximum residue limits (MRL). They can range from zero to a few parts per million (ppm).

Crops and livestock should not have pesticide residues greater than the MRL if pesticides are applied according to label information. The application rates and timing on pesticide labels is carefully calculated so that residues will be less than the MRL when crops are harvested or animals are slaughtered.

Canadian maximum residue limits

Canadian MRL's are listed on the Health Canada website at the following link.

• MRL Database - an online query application that allows users to search for established MRLs for pesticides or food commodities.

The Canadian Food Inspection Agency (CFIA) checks both domestic and imported commodities for pesticide residues when they are sold in Canada. If residues are more than the MRL the commodity may be seized. 

International maximum residue limits

Other countries set their own maximum residue limits (MRL). Canadian produce exported to other countries must comply with the importing countries MRLs. Before shipping products to other countries know what pesticide residues are allowed in that country.  Also be aware that some retailers have their own MRL requirements. 

Pesticide residues in feed

Pesticide application to feed crops may leave residues in or on animal feed. When eaten by livestock, the residues enter the animal and may affect the animal or remain in food. Therefore, Health Canada carefully evaluates pesticides before they can be used in Canada on feed crops and establishes the amount of residues that can be on crops at harvest. Federal legislation prohibits the sale of any feed that presents a risk of harm to human or animal health or the environment. The Canadian Food Inspection Agency administers a national livestock feed program which verifies that livestock feeds manufactured and sold in Canada or imported into Canada are safe, effective and are labeled appropriately.  

If pesticides are applied according to label instructions, then residues on feed should not harm livestock or result in food residues greater than the MRL . The application rates, timing and restrictions on pesticide labels are carefully established so residues will not harm livestock or exceed the MRL at slaughter.

Pesticide residues on crops

Pesticide application to crops may leave residues on the crop and other surfaces within the crop for a short period of time.  The length of this time and the hazard caused by the residue varies widely between products and is influenced by rate and crop species. To protect farm workers from exposure to pesticide residues, the pesticide label indicates re-entry times for each crop. These may be specific to activity.  Workers should not re-enter the crop without protective clothing until the re-entry time has elapsed.   

• Also see Pesticide Re-entry Intervals