Maximum residue levels (MRLs) and import tolerances



A maximum residue level (MRL) is the maximum concentration of a pesticide residue in or on food or feed of plant and animal origin that is legally tolerated when a plant protection product (PPP) is applied correctly (following good agricultural practice).

MRLs apply to most food commodities, although they are not currently applied to fish and produce grown exclusively for animal feed. They are not set specifically for processed commodities. Instead the MRLs for the raw agricultural commodities apply, with processing factors applied to determine the compliance  of processed goods.

An import tolerance is an MRL set on imported food or feed to meet the needs of international trade.

Who must comply with MRLs

If your business is involved in the following activities associated with food or feed you must comply with MRLs

  • production
  • storage
  • processing
  • transport
  • distribution
  • sale

This includes businesses importing food into the UK.

MRLs in Great Britain and Northern Ireland

GB MRLs apply to produce that is:

  • treated in GB (England, Scotland and Wales)
  • imported into GB

EU law and EU MRLs apply in Northern Ireland  - more on MRLs in Northern Ireland.

GB sets MRLs based on our own assessments but all existing EU MRLs adopted as GB MRLs remain valid until they are amended.

GB MRLs and EU MRLs may become different over time.

The MRLs for Great Britain are listed in the GB MRL Statutory Register.

Go to the GB MRL Statutory Register

MRLs are regulated in Great Britain under Retained Regulation (EC) No 396/2005.

Retained Regulation (EC) No 396/2005 - on website

Applying for a new MRL

You may have to apply for a new MRL:

  • when you apply for a plant protection product (PPP) authorisation
  • before you import produce with residues that may exceed the GB MRL (import tolerances)
  • as part of an active substance approval

More about applying for a new MRL

How MRLs are set

MRLs are set at the lowest level consistent with when the plant protection product is applied correctly (following good agricultural practice). MRLs are established using the OECD MRL calculator.

In a limited number of cases temporary MRLs may be set based on monitoring data. For example, this may be to cover environmental contamination or cross contamination. In these cases, the OECD calculator may not be appropriate to establish the MRL.

Apply to HSE to set a new MRL.

Consumer safety

Risk assessments support MRLs which protect all consumers. This includes vulnerable groups such as children. HSE evaluates data on residues in treated commodities and the toxicology of the pesticide. More about the residues data requirements and how consumer risk assessments are conducted.

MRLs are normally set below, and in most cases well below the levels which would pose consumer safety concerns.

MRL monitoring and enforcement

Compliance with MRLs is monitored through a programme of official testing for residues in food and drink.

The PRiF (Expert Committee on Pesticide Residues in Food) advises the Government on the conduct of the monitoring programme. A risk-based approach is applied to the targeting of monitoring activity (focusing on foodstuffs most likely to contain residues or of specific interest).

HSE may take enforcement action if any evidence suggests pesticides are not being applied correctly (following good agricultural practice), or if serious breaches of MRLs occur.

Find out more about the PRiF on GOV.UK

UK Internal Market Act

The approach to monitoring and enforcement is subject to the provisions in the UK Internal Market Act on mutual recognition, as mutual recognition applies to MRLs.

United Kingdom Internal Market Act 2020 -

More about GB MRLs

Is this page useful?

Updated 2024-06-12