Pesticide residues are the very small amounts of pesticides that can remain in or on a crop after harvesting or storage and make their way into the food chain.

Not all foods contain pesticide residues, and where they do occur they are typically at very low levels. Pesticide residues also include any breakdown products from the pesticide.

Pesticide residues can remain even when pesticides are applied in the right amount and at the right time. Sometimes they need to stay on the crop to do their job. For example, they may need to be on the surface of a fruit or vegetable to protect it from pests during storage. Some pesticides are applied after harvest for this purpose.