Regulating pesticides in the UK after Brexit

This guidance is for anyone working with plant protection products (PPPs) after Brexit and covers:

Legislative background

From 1 January 2021, an independent pesticides regulatory regime is in operation in Great Britain (England, Scotland and Wales).

All relevant EU law in relation to the regulation of plant protection products in force on 31 December 2020 was retained in GB law.

Under the terms of the Withdrawal Agreement and Northern Ireland Protocol, EU PPP legislation continues to apply in Northern Ireland. New decisions taken under the EU regime do not apply in Great Britain. This includes active substance and maximum residue level (MRL) decisions and any new EU plant protection product (PPP) legislation.

The laws for Great Britain and Northern Ireland have identical titles, but they may result in differences in requirements for duty holders as divergence happens.

For example, Regulation (EC) 1107/2009 means:

  • In relation to Great Britain, Regulation (EC) 1107/2009 as it has effect in Great Britain
  • In relation to Northern Ireland, Regulation (EC) 1107/2009 as it has effect by virtue of the Protocol on Ireland/Northern Ireland in the EU withdrawal

The Health and Safety Executive (HSE) remains the national regulator for the whole of the UK, on behalf of the UK government and the devolved administrations. 

Pesticides and unfettered access for Northern Ireland goods to Great Britain

The UK Government has committed to unfettered access for qualifying Northern Ireland goods moving to the rest of the UK market.

The UK Internal Market Act 2020 enshrines in primary legislation that qualifying Northern Ireland goods will benefit from a market access principle of mutual recognition. This enables goods to continue to be placed on the whole UK market, even where the Protocol applies different rules in Northern Ireland.

Under the act, mutual recognition allows goods that meets relevant regulatory requirements relating to sale in the part of the UK they are produced in, or imported into, to be sold in any other part of the UK

Pesticide products are specifically excluded however mutual recognition applies to rules on pesticide maximum residue levels (MRLs) in the same way it applies to rules on goods generally.

This means treated produce from Northern Ireland produced in accordance with EU pesticide MRLs can be placed on the market in Great Britain even if EU and GB pesticide MRLs diverge, if it is a qualifying Northern Ireland good. Goods treated with a Great Britain (GB) only authorisation can only be marketed in Northern Ireland (NI) if the relevant EU MRL is in place.  


On 1 January 2021 active substance approvals, MRLs and assessment criteria were identical in EU and GB. As changes occur in either regime, divergence is introduced. This divergence can result in necessary differences in authorised pesticide uses in GB and NI, and in the MRLs applying, and may have an impact on trade of pesticide products or treated goods.

For example:

  • If an MRL is raised in GB but the same change is not yet in force in EU, a new GB only authorisation for the corresponding use may be issued. However, the goods treated under this authorisation may exceed the EU MRL, in which case it will not be possible to trade these goods in EU or NI until such time as the EU MRL is raised
  • If an MRL is raised in EU and goods treated in accordance with the corresponding EU member state authorisation and the GB MRL remains the same, it may not be possible to import treated goods into GB. An import tolerance application may be required to raise the MRL in GB –this does not apply to the unfettered access of qualifying goods from NI to GB
  • If an active substance approval is renewed, non-renewed or amended in EU, the NI product authorisation may also be amended or withdrawn, whilst the existing pesticide use may remain available for sale and use in GB

Whenever possible, HSE aims to issue authorisations common to both GB and NI.

Active substance approvals

An active substance must be included in the statutory GB Pesticides Approvals Register before it can be included in any PPP authorised for use in Great Britain.

The GB Pesticides Approvals Register provides a full list of approved active substances which can be included in plant protection products in Great Britain, together with details on the specific conditions of approval. Many of these are approved as a result of EU legislation being adopted into GB law.

So the GB programme to review the safety of active substances can be developed, active substance approvals due to expire before December 2023 were extended for 3 years. HSE, however, retains the power to review active substance approvals at any time, if new evidence identifies any concerns to human health or the environment.

Expiry dates and renewal of active substances

An active substance must be approved in EU before it can be included in any PPP authorised for use in Northern Ireland.

EU Pesticides database (Europa website)

Maximum Residue Levels (MRLs)

GB MRLs apply to produce both treated in and imported into Great Britain. Pesticide MRLs for GB are established in the GB MRL Statutory Register.

Great Britain sets new MRLs based on our own assessments but many existing MRLs resulted from EU legislation being adopted into GB law on 1 January 2021.  All those transferred EU MRLs remain valid until they are amended for example to accommodate a new authorisation or to allow the import of treated commodities into GB. HSE, also retains the power to review the MRLs at any time, if new evidence identifies any concerns for human health or the integrity of the MRLs.

Applicants still need to meet existing conditions, such as supplementary data requirements, under the new GB pesticide regime.

Businesses producing food for export or trading in food produce should consider the implications of MRL divergence.

MRLs in Northern Ireland.

Product authorisations

UK pesticide authorisations are available from the HSE Pesticides Register and extension of minor use’ databases.  These databases identify the extent of the authorisation as GB+NI, GB only or NI only.

Where divergence creates separate authorisations in GB +NI, GB only or NI only, separate MAPP numbers for the product in the different regimes are required.

The only exceptions to this are where a GB only or NI only extension of authorisation is granted for a GB+NI product or when the divergence is in the product expiry date only.

MAPP numbers.

Product expiry dates

Product expiry dates use the date of the earliest expiring active substance in the product.

Since 1 January 2021 different active substance expiry dates apply in the EU and GB. To avoid unnecessary divergence, the product expiry date for ‘GB and NI’ authorisations is generally set based on the earliest of the GB and EU active substance expiry dates.

In some cases, an EU or GB decision on the active substance may mean that applying the earliest expiry date for both regimes is no longer appropriate. For example, where an EU decision results in changes to product authorisations in Northern Ireland, the authorisations in GB can continue until a GB decision is taken. In this case separate amendment notices will be issued giving different expiry dates in GB and NI for the same MAPP number. On the GB Pesticides Register this will result in more than one result for the same MAPP number; each with different expiry dates and 'extent of authorisation'.

New applications

Applicants for new active substance approvals, PPP authorisations and MRLs in Great Britain should continue to submit applications to HSE in the same format.

Where possible a single application for GB and NI should be submitted. Where divergence issues prohibit a common authorisation, separate applications for GB and NI are required. There are no changes in data requirements or format for supporting information.

New GB authorisations must be based on a GB decision process and HSE cannot accept new applications which are reliant on EU Member State assessments. We do welcome the provision of any competent authority assessments (from the EU or wider) which may help to inform the GB decision making.

  • All EU guidance in place at the end of the transition period applies in GB unless we take a decision to remove or replace it.
  • Any guidance implemented in the EU after the end of the transition period does not apply in GB unless we take an active decision to use it.

Whilst Northern Ireland authorisations must follow EU rules, HSE is not able to act as a lead authority in the zonal processes. This means that assessments relevant to Northern Ireland only, must be undertaken by an EU Member State, with Northern Ireland treated in the same way as a concerned member state. This is particularly relevant for:

  • NI only product renewal applications (article 43) with reference to EU active substance renewal decisions after 1 January 2021
  • New sources of active substance for use in a GB+NI or NI only product authorisation

If a product is authorised in NI but not any EU member state it may be possible for HSE to undertake the assessment.

Mutual recognition of EU product authorisations can continue to be considered for Northern Ireland only.

Ongoing following zonal applications

There remain some applications submitted as following zonals prior to UK leaving the EU, where the zonal rapporteur member state (zRMS) is yet to conclude its evaluation. These are either Article 33 (new product/use applications) or Article 43 applications. An audit of these applications is ongoing.

If the use is for Northern Ireland only, the originally proposed EU following zonal approach can be used, otherwise applicants can continue to support via one of the following methods:

Article 33 applications

  • provide the registration report once it is finalised by the zRMS. HSE can then process the application, using that information, noting that the zRMS Part C is unlikely to be available
  • request that HSE undertakes a full evaluation of the original submission. The guidance at the time of submission will be used
  • submit a new updated Article 33 to which latest guidance and templates will apply

Article 43 applications

Products supported at the Article 43 deadline remain authorised until the product renewal process is complete. We will contact applicants to determine the status of the zRMS assessment to inform the most appropriate route to upgrade the assessment.

HSE will continue to make use of other regulators' assessments where relevant and appropriate to support GB decisions.

In each case HSE will continue to evaluate each application and make a GB only decision. Where there is no divergence, a GB + NI authorisation may be issued.

Parallel trade permits

HSE withdrew parallel trade permits in Great Britain with a final sale date of 30 June 2023 and final use date of 30 June 2024.

The Plant Protection Products (Miscellaneous Amendments) (EU Exit) Regulations 2023 has allowed for parallel permits to be temporarily re-instated in GB for a limited time.

Find out how to apply for temporary re-instatement of a parallel permit.

Applications for new parallel trade permits will be considered for Northern Ireland only.

Treated seed

Seed that has been treated with a product authorised for that purpose in an EU member state can continue to be traded and used in Great Britain up to 30 June 2027. From 1 July 2027 onwards, treated seed can only be traded and used in Great Britain if it has been treated with a PPP authorised for that purpose in Great Britain. During this period applicants should get any new GB PPP authorisations they need.

Pesticide users

Existing PPP authorisations made under the EU pesticides regime remain valid in Great Britain. Authorised PPPs can be placed on the market and used in the same way as before.

Only use authorised products and always follow the instructions on the label to ensure MRL requirements are met in the domestic market where the food is grown. If produce is intended for export, check the MRL requirements in the target markets. MRLs in Great Britain and the EU may begin to diverge over time, which might affect which pesticide products you can use on produce intended for export.

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Updated 2023-12-08->->->->->