Chemical residues in food: pesticides and veterinary medicines

Chemical residues are traces of pesticides (used on crops) or veterinary medicines (used on food-producing animals) that can remain in food. They may be found in fruit, vegetables, cereals, meat, milk, eggs and other animal products.

Food businesses are responsible for ensuring that the food they produce or import is compliant with current legislation, including rules on specified maximum residue levels.

What are maximum residue levels (MRLs)

MRLs are the maximum amounts of residue likely to remain in food when a product like a pesticide or veterinary medicine has been used correctly. They are set so that dietary intake remains within safe levels for consumers.

MRLs are expressed as milligrams of residue per kilogram of food product. Before being approved for use, pesticides and veterinary medicines must be proven to be completely safe for human consumption at their MRLs - and usually safe at much higher levels. National monitoring programmes regularly sample foods to check that residues are within legal limits. If residues above the MRL are found, authorities can investigate and take enforcement action.

Pesticide residue levels in food and feed

Pesticides are used in agriculture, horticulture and domestic gardening to control pests, weeds and diseases. Small amounts of pesticides can remain in or on food as residues.

In the UK, the Health and Safety Executive (HSE) authorises which pesticides can be used and how. The Food Standards Agency (FSA) works closely with HSE on pesticides and food safety.

The Department for Environment, Food & Rural Affairs sets pesticide MRLs in Great Britain to make sure residues in food are not harmful to people.

In Northern Ireland, European Union MRLs apply to food or feed produced in or imported into and marketed within NI - this excludes goods moved from GB under the Northern Ireland retail movement scheme. See guidance on pesticide MRLs in Northern Ireland.

How to comply with pesticide MRLs

If you grow, import, process or sell food, you must:

• buy products from reputable suppliers who follow pesticide rules
• keep invoices, specifications and certificates showing products meet MRLs
• respond quickly to food alerts or residue findings affecting your supply chain
• co-operate with any official sampling or investigations

Information on EU pesticide law and procedures is also available on the European Commission website. You can search for EU MRLs in the EU pesticides database.

Veterinary medicines residue levels in food and feed

Veterinary medicines are used to treat and prevent disease in animals, including animals used for food. Traces of these medicines can remain in meat, milk, eggs and other animal products.

In the UK, the Veterinary Medicines Directorate (VMD) assesses veterinary medicines before they are authorised. In Great Britain, VMD sets UK MRLs for veterinary medicines and ensures they are safe for consumers. In Northern Ireland, EU MRLs for veterinary medicines apply under EU law.

The FSA assesses any food safety risks from residues in food, and enforcement in Northern Ireland is carried out by the relevant NI authorities, including the Department of Agriculture, Environment and Rural Affairs, under the veterinary medicines and food law frameworks.

How to comply with veterinary medicines MRLs

If you keep food‑producing animals, you must:

• use only authorised veterinary medicines and follow dosage instructions
• observe withdrawal periods before animals, milk or eggs enter the food chain
• keep accurate records of all treatments and medicine use
• co‑operate with any official residue testing and investigations

If you buy animal products for processing or retail, you should:

• purchase from reputable suppliers who follow veterinary medicine rules
• keep supply chain documentation to show where animal products came from

Residue monitoring programmes run nationally. If residues exceed MRLs, national agencies and enforcement bodies can investigate farms or supply chains to identify and resolve the issue.