Corporate report

UK competent authorities for pesticide residues in food: annual report for 2023

Published 2 July 2025

About food monitoring programmes

The Health and Safety Executive’s (HSE) Food Monitoring Programmes check food and drink in Great Britain (England, Scotland and Wales) and Northern Ireland for traces of pesticide residues on behalf of Defra (Department for Environment, Food and Rural Affairs), the Northern Ireland Executive, the Scottish Government and the Welsh Government.

One of the purposes of the programme is to check whether residues found in food (by food in this report, we mean both food and drink) are above the maximum residue levels (MRLs) set by law.

HSE administers a food monitoring programme that:

• when residues are detected, conducts risk assessments to identify whether the levels found are likely to impact on human health – this is done for all residues, whether or not the MRL is exceeded
• assesses the risk of residues detected on various consumer groups that include particular groups of vulnerable consumers such as babies, toddlers and the elderly
• where more than one pesticide is found with similar modes of action for certain chemical groups of pesticides, identifies if the impact of the sum of the residues is of concern
• when problems are found, takes action including additional testing
• check that results align with those set by the regulatory regime when the law on using the pesticides or on pesticide residues in food were set
• communicates with suppliers and food producers – this communication often drives positive impact work for the supply chain

This report from HSE summarises the results from monitoring samples collected throughout 2023 and our conclusions about those results. It also describes the work that is being carried out in 2024.

Details of all the samples HSE have collected and tested are available at: Pesticide Residues in Food Data on data.gov.uk.

If you have any comments about this report, please send them to pesticideresiduesteam@hse.gov.uk.

Executive summary

Pesticides used in farming can result in residues being left in the food which is produced. In order to provide a high level of protection for consumers, there are strict controls on the levels of pesticide residues that are permitted in food. The maximum residue levels (MRLs) are not in themselves safety limits but are based on the levels that occur if the pesticide has been used correctly. They are always set below and usually well below, the level considered to be safe for consumers. There is an ongoing monitoring programme to analyse the levels of pesticides present in different foods and provide assurance that food in the UK complies with these strict rules.

This report contains details of the 2023 pesticide residues in food monitoring programme. It describes how pesticides are regulated and the role that MRLs in foods form as part of these controls, the role of the Food Standards Agency (FSA) in relation to this work, the make-up of the monitoring programme, details of headline and key results, how findings are assessed to determine any risks to consumers and how follow up action is taken on particular findings and results.

The Health and Safety Executive (HSE) organises this monitoring programme and reports findings on behalf of Defra and the Governments of Scotland, Wales and Northern Ireland and publishes quarterly reports of the findings. HSE can seek advice from the Expert Committee on Pesticides Residues in Food (PRiF) in relation to make up of the programme and the communication of results – the committee’s report of its activities in 2023 can be found at Pesticide residues in food: quarterly monitoring results for 2023.

Food is sampled from a range of retail, wholesale, port, distribution depots and processor factory locations across the UK, as detailed in this report, and analysed for the presence of a large number of pesticides. The findings are assessed, initially for compliance with MRLs and also to determine whether there are any implications for the short and long-term health of those consuming the produce. Where appropriate, follow up action may be taken to establish the cause of particular findings and/or determine whether compliance/enforcement or other action should be taken. Details of the programme’s findings, assessments and associated activity are published in the quarterly reports.

The monitoring programme is risk based, looking at those foods in which we expect to find residues. Overall results show that the vast majority of food we tested (98.22%) complied with legal limits for pesticides in that food. The compliance rates in this year’s report are broadly similar with monitoring results in previous years.

The following results summarise the 2023 programme which analysed 3,647 samples of 28 different foods:

• 1,791 samples (49.11%) had none of the residues HSE looked for
• 1,798 samples (49.30%) had residues found at or below the MRL
• 58 Samples (1.59%) had residues above the MRL

The report breaks down these findings presenting separate results for Great Britain and Northern Ireland and the types of foods (fruits and vegetables, starchy foods and grains, animal products and miscellaneous foods). It also provides details of all samples containing residues above the MRL. All of the samples in which a residue was detected were checked for risk to consumers. The quarterly reports of 2023 programme contain details of 48 short term risk assessments where it was concluded that further work was necessary, on findings detailed in this report, to assess potential impacts on consumers. Of these a small number, 11, led the Food Standards Agency (FSA) to follow up with appropriate action.

Roles of HSE and the competent authorities for pesticide residues

The term ‘pesticide residue’ means the chemical trace of a pesticide which may be found in or on our food. The agriculture and food industries use pesticides to help protect their crops from pests, including insects, weeds or fungal infections.

The UK competent authorities for pesticides and pesticide residues in food are:

• Defra (for England)
• Scottish Government
• Welsh Government
• Northern Ireland Executive

Great Britain legislation states the 3 Great Britain competent authorities:

• may co-operate to produce and deliver a Great Britain control plan
• must produce and deliver a control plan in their territory
• must co-operate to prepare an annual report of the results

Northern Ireland is subject to Northern Ireland law, which requires them to have a control plan, and to publish their results annually.

In practice all 4 competent authorities delegate the relevant powers and responsibilities to HSE which delivers the requirements of a combined Great Britain control plan and a Northern Ireland control plan.

The Great Britain programme included all common testing as required by British law (Commission Implementing Regulation (EU) 2019/533 as retained in Great Britain law) plus an additional programme of national testing. The Northern Ireland included all common testing as required by law (Commission Implementing Regulation (EU) 2022/741) plus an additional programme of national testing.

HSE regularly publish clear, understandable monitoring results at Pesticides Residues in Food on data.gov.uk, and aim to do this as quickly as possible without compromise to the integrity of the programme.

HSE can seek advice from the Expert Committee on Pesticide Residues in Food (PRiF), which was formed in 2011, to carry on the advisory function of the Pesticide Residues Committee which ceased to operate in 2010.

The members are appointed to advise ministers from Defra, the Scottish Government, the Welsh Government and the Department of Agriculture, Environment and Rural Affairs for Northern Ireland.

They give advice on the monitoring programme to:

• ministers
• the Chief Executive of the Food Standards Agency (FSA)
• the Health and Safety Executive

They meet 4 times a year and representatives from government departments attend the meetings as officials. HSE provides the committee’s administration.

Background on pesticide regulation

Pesticides can only be used in UK if they are used in line with the law and guidance controlling their use.

On behalf of UK agricultural departments, HSE authorises and controls pesticides for use in the UK, sets MRLs for food traded in the UK, and monitors pesticide residues in the UK food supply. MRLs are set for and apply to food available in the UK no matter where the food was produced. The FSA has overall responsibility for food safety.

Most residues come from pesticides being used on crops. To work effectively, pesticides must be used in the correct amounts and at the right time. The amount of residue in or on a food is dependent on:

• how much pesticide was used
• when it was applied in relation to harvest date
• how it is metabolised by plants and animals
• how it breaks down in the environment

In addition to this, residues can sometimes be present due to contamination (small amounts of pesticide that remain in the environment after legitimate use). Due to significant technical improvements in laboratory analysis, we now have the capability to detect very low levels of residues. So, it is possible that, as methods become more sensitive, we may find more residues.

HSE publish the results, including brand names, where samples were obtained and where possible who produced them. The open reporting system has encouraged producers and retailers to be responsible about their use of pesticides in their supply chains.

Maximum residue levels

MRLs are set in law at the highest level of pesticide that the relevant regulatory body would expect to find in that crop when it has been treated in line with Good Agricultural Practice (GAP). When MRLs are set, effects of the residue on human health are also considered. The MRLs are set at a level where consumption of food containing that residue should not cause any ill health to consumers.

If a food has a higher level of residue than the MRL, it does not automatically mean that the food is not safe to eat. A residue above the MRL may show that the farmer has not used the pesticide properly. Some pesticides may be permitted for use in the country of export but not be permitted for use in Great Britain and/or Northern Ireland, and so the MRL may be set at the lowest level that official laboratories can normally detect.

This is known as the limit of determination (LOD). An LOD MRL is indicated by an asterisk after the level (for example, 0.01* mg per kg).

The Food Standards Agency

The main objective of the FSA is to protect public health from risks that may be associated with the consumption of food (including risks caused by the way in which it is produced or supplied) and otherwise to protect the interest of consumers in relation to food. The FSA attends PRiF meetings as an assessor and works closely with HSE, on pesticide residues issues.

The FSA has responsibility for food safety and compliance monitoring. This responsibility is delegated to the port health authorities and local authorities at Great Britain’s points of entry. Most non-animal origin food is subject to limited surveillance activity in regard to pesticides, however, certain commodities which are assessed to present a greater risk to public health are regulated for in assimilated Regulation 2019/1793, which stipulates commodities and countries of origin that present a particular concern and are subject to additional controls. This may include but is not limited to pesticide analysis at the border control point of entry. However, testing of imports at the border is separate to the HSE monitoring programme.

The 2023 pesticide residues in food programme identified a relatively small number of products with residues above the MRLs. As outlined above, MRLs are not by definition “safety limits” and therefore they should not be considered as such. Where the MRLs have been exceeded and the risk assessment process indicates there may be a risk to health, HSE sends these cases to the FSA to determine if further action is required. An assessment is agreed and if there is an appreciable risk to health from the presence of these pesticide residues, including a concern around genotoxicity then appropriate action is taken. Appropriate action could include the following: withdrawal or recall of the product from the market via local authority contacts and where necessary notify the International Network Food Safety Authorities (INFOSAN) Emergency Contact Point in the exporting country of the non-compliance and safety risk. This year, the commodity grouping defined as beans with pods has featured most heavily as the one which has the most analysed non-compliances in this survey. Results from the PRiF programme contribute to the data used as intelligence fed into the FSA’s Early Warning System (EWS) which suggests to port health authorities which imports checks should be prioritised. Repetitive high-risk issues found via the EWS can lead to consideration for inclusion on the intensified official controls regulations (assimilated regulated 2019/1793).

For the 2023 survey results, which were referred to the FSA and subsequent risk management advice of a withdrawal was provided, the following considerations were made. FSA have considered the European Food Safety Authority (EFSA) 2018 Conclusion in our risk assessments with regards to the uncertainty around the genotoxicity of dimethoate, and of omethoate (the breakdown product of dimethoate) which is considered genotoxic and therefore its presence at any level can be considered as undesirable to health. The FSA considers chlorpyrifos to have uncertainty regarding its genotoxicity. The FSA considers the presence of carbofuran to be undesirable due to concerns around genotoxicity. Based on this consideration, we will follow up samples containing residues above the MRL which contain any of these pesticides.

Since exiting the EU, the UK has third country access to the EU’s Rapid Alert System for Food and Feed (RASFF) and can only see RASFF alerts which affect the UK. The FSA has significantly increased engagement with the World Health Organisation (WHO) and Food and Agriculture Organisation of the United Nations (FAO) funded INFOSAN as a mitigation for loss of RASFF and other EU incident and emergency communication systems. INFOSAN gives a reach to authorities in 194 countries, which allows direct engagement on common topics of interest with trade partners. If the FSA identifies a health risk with an imported food product via surveillance programmes, then we will notify the exporting country’s INFOSAN Emergency Contact Point.

Monitoring programme design

The planning of the annual programme takes into consideration a number of relevant influencing factors including, previous sampling results, analysis, national diet trends and evidence from other regulators to the programme. As the programme is designed to be one of monitoring to determine compliance with legal levels of pesticide residues in food rather than to be a reactive one it is unlikely to change significantly throughout the year, but as mentioned above, incidents that arise are taken into consideration for the following years programme.

The 2023 monitoring programme

HSE tests food to determine whether the levels of any pesticides found meet legal trading levels and if there is any risk to people’s health.

Collecting and testing samples

The size of the sample and the number of individual units of a food within each sample is set down in regulation. For example, for apples the sample must be made up of at least 10 apples and weigh at least 1 kilogram.

HSE sends samples to the following laboratories to be tested:

• Agri Food and Bioscience Institute (AFBI) – Belfast
• Fera Science Ltd – York
• SASA – Edinburgh
• SCL – France

Residues tested for

HSE tests food for a large list of pesticides in the laboratories. Over the last 20 years the number of pesticides we test for has risen. The increase is consistent with the current capability of most laboratories which test food for pesticide residues.

The choice of pesticides tested for in a survey depends on:

• which pesticides have been found before
• what we know is being used to grow specific foods, (that is, which pesticides are approved for certain crops)
• what we know about pesticides used in the UK and other countries
• what we know about pesticides being found in tests in other countries
• the risk residues of that pesticide may present
• the maximum residue levels set in law

Why HSE chose certain foods

There is a wide range of foods available in the UK throughout the year. To make the most of resources and ensure we test a wide range of food, the programme changes from year to year.

When we choose the foods to test, we take account of many factors. Some foods are so common in our diets that even if previous testing showed few or no residues, it is right to carry on checking them. Although there have been no recent health concerns, we continue to monitor staples like milk and bread because of their role in the UK diet.

We group the foods into 5 categories:

• fruit and vegetables
• animal products
• starchy food and grains
• miscellaneous groceries
• infant food

Other foods are less commonly consumed but are important in the diet of some groups of people, for example, speciality fruit and vegetables. So, we check these to protect those who consume these foods most frequently or in the greatest amount. Some foods that are not staples in our diets are still included most years because we regularly find residues in them that are not compliant with the MRLs.

HSE work with the Expert Committee on Pesticide Residues in Food (PRiF) to seek advice about new trends in diets, for example, the increased interest in and broader range available of gluten free food or meat substitutes such as soy or tofu in recent years. We bear in mind different shopping habits in the sampling programme, to include buying from street markets, greengrocers, or supermarkets.

We also take account of monitoring data from other countries including information from the EU Rapid Alert System for Food and Feed (RASFF). The RASFF system is used to share notifications of foods which could be a risk to human health.

40 foods of dietary importance are collected over a 3-year period as part of a Great Britain multi annual control programme established in legislation. In 2023, oranges, pears, kiwi fruits, cauliflowers, onions, carrots, potatoes, beans (dried), bovine (liver), poultry, rye grain, brown rice (husked rice), formed part of this larger survey. The same foods were tested in Northern Ireland as part of a similar EU wide programme.

Each year we publish our proposed list of foods to be sampled. In 2017 HSE developed, in conjunction with the PRiF, a monitoring matrix ranking tool which helps determine the priority of the relative surveys. This provides a more objective approach.

HSE publish detailed results from the programme every 3 months on GOV.UK and data.gov.uk.

The reports are published in 2 parts. The first is the Quarterly Summary report which details the findings, risk assessments that were carried out and any comments from the committee. This part of the report is published on the GOV.UK website.

The other part of the report provides all the sample details, such as brand name found in each survey. This part of the report is published in an accessible format on data.gov.uk website.

Report	Sample Collection	Report Published
Quarter 1 2023	January to March 2023	March 2024
Quarter 2 2023	Up to June 2023	March 2024
Quarter 3 2023	Up to September 2023	September 2024
Quarter 4 2023	Up to December 2023	September 2024

All the results for samples collected in 2023 are available for download at Pesticide Residues in Food Data on data.gov.uk.

Surveys are reported separately for samples collected in Great Britain and those collected in Northern Ireland (NI). The government has experienced delays in receiving results for some samples collected in Northern Ireland due to delivery issues. The Northern Ireland data for products of plant origin and infant food (Quarters 2 to Quarter 4) were published in May 2025.

The information published includes:

• where and when samples were collected
• country of origin, as shown on labelling at the point of sampling
• brand names, if available
• pesticides detected and if so whether the residues were above the MRL
• reporting level for all pesticides tested for including those sought but not found.

The advice of the PRiF was sought on the results obtained each quarter. Their detailed reports are available at Pesticide Residues in Food Quarterly Reports.

Part 1: Results from the UK 2023 programme

Summary of the results for UK (Great Britain and Northern Ireland combined)

The programme tested 3,647 samples each for an appropriate range of pesticides. In total we tested around 1,091,870 food and pesticide combinations. For Great Britain and Northern Ireland combined, HSE surveyed 30 different commodities, collected 3,647 samples, and carried out 48 detailed risk assessments in 2023.

There were some differences in the foods surveyed between Great Britain and Northern Ireland. Brussel sprouts was only surveyed in Northern Ireland. Crisps (potato based), orange juice, pulses (dahls/lentils), snacks (cereal based) and snacks (speciality) were only surveyed in Great Britain.

The following results summarise all the UK surveys:

• 1,791 samples (49.11%) had none of the residues HSE looked for
• 1,798 samples (49.30%) had residues found at or below the MRL
• 58 Samples (1.59%) had residues above the MRL

Overall UK survey results 2023

	Percentage (%) of samples
None of the residues HSE looked for	49.11%
Residues found at or below the MRL	49.30%
Residues above the MRL	1.59%

All of the samples in which a residue was detected were checked for risk to consumers by means of a risk assessment screening mechanism. In the PRiF quarterly reports of 2023 we published results of 48 detailed short term risk assessments where we wanted to consider in more detail whether there was a concern for human health. Great Britain and Northern Ireland results are assessed together for risk so these assessments cover samples from both surveys.

Of these a small number, 11, led the FSA to follow up with appropriate action.

HSE refer information about food samples to the FSA where, following risk assessment, we have concerns about the potential risk to health of people eating these foods.

Consumer risk assessment

HSE conducts a screening assessment of all the residues we find in the pesticide residues in food monitoring programme. If screening identifies any dietary intakes exceeding the relevant health-based reference values, then we conduct more detailed risk assessments, to consider whether there are any implications for health. Detailed risk assessments, where needed, are presented in the quarterly reports. If we understand that a pesticide residue has a risk of genotoxicity, we will include this in the commentary. 

Pesticide dietary intakes are assessed using models that combine data on the levels of residues in food with food dietary consumption values. If intakes are within the health-based reference values, then taking account of the precautions built into the model assessments we conclude that an effect on health is not anticipated. If dietary intakes exceed the reference values this does not automatically mean there are expected adverse health effects. However, this acts as a ‘trigger’ for HSE to consider these cases more thoroughly. 

HSE conducts both short-term (acute) and long-term (chronic) assessments based on the residues found in the pesticide residues in food monitoring programme surveys. Each of these is tailored accordingly. Further information on the nature of HSE’s assessments and approach is provided in the bullet points below. More detail, with reference to international assessment contexts, is available in the quarterly reports.

• For acute assessment, we use short-term estimation values that use the highest residue found in a commodity and short-term consumption values for calculating short-term dietary intakes. These are then compared to the Acute Reference Dose (ARfD), a suitable health-based reference value for effects that could be caused by a single day or one-off consumption of a higher than usual residue. For acute assessment we consider the variation in residues that could occur within a residue sample, and a variability (multiplication) factor is included for that purpose, in order to address exposure to a higher than usual residue in a single item, such as a single apple or potato
• For chronic assessment, we use long-term estimation values (based on median residues and long-term consumption values for calculating long-term dietary intakes) for each commodity quarterly survey and compared to the Acceptable Daily Intake (ADI), a suitable health-based reference value for life-time. The issue is more fully considered in regulatory contexts pre-authorisation and at the time of MRL review. Then the issue is considered across all commodities (so more precautionary) by pesticide levels determined in GAP compliant trials, intended to address highest likely residues that might arise following pesticide use according to label recommendations
• For fruit and vegetables that have peel or skin that might not be consumed we present alternative risk assessments for ‘without peel-flesh only’ where peel versus pulp residue distribution data is available – as standard, we present a ‘worst case’ assessment for when all of the peel is consumed
• We calculate dietary intakes for different consumer groups from infants, toddlers and children of varying age, to adults, elderly, and vegetarians, to take account of people with low bodyweights and varying dietary habits – as such the assessments we perform are protective for all consumers
• For multiple residues, we consider the possible implications to health of more than one pesticide being found in samples (sometimes called the ‘cocktail effect’) – we currently focus in detail on selected groups that we think are a priority to consider based on toxicity considerations and prevalence

If samples of UK grown produce contain residues of pesticides not authorised for use in the UK on those crops, they are followed up by HSE. Where they could not identify an obvious reason for the residues, they investigated with the grower or supplier to determine how these residues could have arisen.

Full details are provided in the quarterly reports. The following explanations are for the 6 UK samples that required further follow up: 

• 3 samples of carrot contained linuron, the presence of low level residues could have occurred as the pesticide has the potential for persistence in soils
• HSE found low levels of residues of chlormequat in conference pears, where spray records did not indicate use of the active – these could have arisen due to spray drift from the legitimate use of the pesticide on cereal crops in very close proximity to the orchards
• HSE found residues of spinosad in sugar snap peas, where spray records did not indicate use of the active – this could have arisen due to spray drift from the legitimate use of the pesticide on another crop in close proximity to harvest dates – HSE has given appropriate information regarding duties under the Plant Protection Products (PPP) legislation
• One sample of conference pears contained diuron, the presence of low-level residue could have occurred as the pesticide has the potential for persistence in soils
• none of these residues were found to be the direct consequence of the misapplication of a pesticide requiring enforcement action. There was no food safety issues associated with these residues

The monitoring programme is risk based as it looks at those foods in which we expect to find residues. Because of this, we cannot say that the results represent the UK food supply as a whole.

Foods being sampled in 2024

• Aubergine
• Banana
• Beans (dried) (Great Britain only)
• Beans with pods
• Beef
• Beetroot
• Bread
• Broccoli
• Chilli peppers
• Eggs
• Fish (white)
• Garlic
• Ginger (Great Britain only)
• Grapefruit
• Grapes
• Honey (Great Britain only)
• Infant food (cereal based)
• Limes
• Melon
• Milk
• Mushrooms
• Olive Oil
• Peppers (sweet)
• Potatoes
• Potatoes (processed) (Great Britain only)
• Speciality vegetables (root) (Great Britain only)
• Sweet potatoes (Northern Ireland only)
• Tomatoes (processed) (Great Britain only)
• Wheat flour

Sampling locations

Each year, samples are collected from different places throughout the UK. At least 2 towns or cities are chosen from each government region. In 2023, we collected 3,647 samples in total from both retail outlets in towns or cities in the UK and government inspectors collected around 660 of these samples from places such as wholesalers, ports, supermarket distribution depots and processor factories.

2023 Survey towns and cities

England

• Barnet
• Blackburn
• Blackpool
• Bristol
• Colchester
• Dagenham
• Fareham
• Huddersfield
• Leeds
• Newark
• Norwich
• Okehampton
• Rugby
• Sunderland
• Worksop

Northern Ireland

• Ballycastle
• Belfast
• Londonderry
• Newry

Scotland

• Dundee
• Glasgow

Wales

• Llanelli
• Newport

Foods tested in 2023

As some foods are available at different times throughout the year from different parts of the world, we may collect samples of these foods over 3, 6, 9 or 12 months. We sometimes report results of tests every 6 months rather than every 3 months. We do this when there are only a small number of samples in a survey or when we do not expect there to be many residues of interest in the results because analysing larger batches of samples is more economical.

We publish detailed results from the programme every 3 months. Reports for 2023 are available through Pesticide Residues in Food Quarterly Reports webpage.

The reporting timetable for samples of plant-based food and infant formula from samples collected in Northern Ireland was delayed. These results were published as supplementary information later than the Great Britain collected samples.

Quarter 1 2023

• Beans (dried)
• Beans with pods
• Carrots
• Cauliflower
• Fish (oily) (Northern Ireland only)
• Grapes
• Kiwi fruit
• Lemons
• Liver (bovine)
• Milk
• Onions
• Oranges
• Pears
• Peas edible pods
• Pineapples 
• Potatoes
• Poultry meat
• Rice
• Rye flour (Northern Ireland only)
• Soft citrus

Quarter 2 2023

• Beans (dried)
• Beans with pods
• Bread
• Carrots
• Cauliflower
• Fish (oily)
• Grapes
• Kiwi fruit
• Lemons
• Liver (bovine)
• Milk
• Onions
• Oranges
• Pears
• Peas without pods
• Pineapples
• Potatoes
• Poultry meat
• Rice
• Rye flour
• Spring onions (Northern Ireland only)
• Soft citrus

Quarter 3 2023

• Beans (dried)
• Beans with pods
• Bread
• Brussel Sprouts (Northern Ireland only)
• Carrots
• Cauliflower
• Fish (oily)
• Grapes
• Infant formula
• Kiwi fruit
• Lemons
• Liver (bovine) (Northern Ireland only)
• Milk
• Onions
• Oranges
• Orange juice (Great Britain only)
• Pears
• Peas edible pods
• Pineapples
• Potatoes
• Poultry meat
• Pulses (dahls/lentils) (Great Britain only)
• Rice
• Rye flour (Northern Ireland only)
• Snacks (cereal based) (Great Britain only)
• Spring onions
• Soft citrus

Quarter 4 2023

• Beans (dried)
• Beans with pods
• Bread
• Brussel Sprouts (Northern Ireland only)
• Carrots
• Cauliflower
• Crisps (Great Britain only)
• Fish (oily)
• Grapes
• Kiwi fruit
• Lemons
• Liver (bovine)
• Milk
• Onions
• Oranges
• Orange juice (Great Britain only)
• Pears
• Peas without pods
• Pineapples
• Potatoes
• Poultry meat
• Rice
• Rye flour
• Snacks (speciality) (Great Britain only)
• Soft citrus

Analysis of risks to UK consumer health

Action taken

FSA were aware of all findings and risk assessments. For foods labelled as UK and with residues over the MRL, or with brand owners based in the UK, the producers were contacted.

For foods labelled as or established as produced overseas with residues over the MRL where following risk assessment further consideration was needed, full details were forwarded to the FSA to consider forwarding via the INFOSAN network operated by the World Health Organisation. This would enable future preventative actions.

HSE found several samples of beans with pods with residues exceeding the MRL where following risk assessment further consideration was needed. HSE have passed details of these samples to FSA who followed up with the relevant suppliers. The suppliers have withdrawn the remaining packs and INFOSAN notices have been issued for these findings.

We found some residues of pesticides where we cannot exclude genotoxic potential. These pesticides are not authorised for use in the UK or EU, and the evaluator (EFSA in all we have examined in 2023) considered it was not possible to exclude this risk nor to set safety levels. It is unlikely a pesticide company or an organisation representing users would find it economical to provide a modern data package for older pesticides, particularly when not authorised in Great Britain or the EU. But HSE cannot set higher MRLs or enable the risk assessment to be completed without that information. Therefore, the issue of the approach to residues needs to be resolved via the pesticide or residues review process.

In the meantime, HSE has ensured that a lower than normal detection limit is used for these pesticides, to give a broader picture of incidence and inform future considerations.

Part 2: Results from the Great Britain 2023 programme

Overall results

In 2023, HSE tested 2,574 samples from 29 different food surveys sampled in 23 towns and analysed for up to 418 different pesticides.

The following results summarise all the Great Britain surveys:

• 1,235 samples (47.98%) had none of the residues HSE looked for
• 1,286 samples (49.96%) had residues at or below the MRL
• 53 samples (2.06%) had residues over the MRL

Great Britain survey, overall results 2023: 2,574 samples

	Percentage (%) of samples
None of the residues HSE looked for	47.98%
Residues found at or below the MRL	49.96%
Residues above the MRL	2.06%

Food sampled from Great Britain from the UK

The following results are for Great Britain surveys labelled as UK produced:

• 890 samples (60.22%) had none of the residues HSE looked for
• 568 samples (38.43%) had residues found at or below the MRL
• 20 samples (1.35%) had residues above the MRL

Great Britain survey, food from UK 2023: 1,478 samples

	Percentage (%) of samples
None of the residues HSE looked for	60.22%
Residues found at or below the MRL	38.43%
Residues above the MRL	1.35%

Food sampled from Great Britain from outside the UK

The following results are for Great Britain surveys labelled as produced outside of the UK:

• 345 samples (31.48%) had none of the residues HSE looked for
• 718 samples (65.51%) had residues found at or below the MRL
• 33 Samples (3.01%) had residues above the MRL

Great Britain survey, food from outside the UK: 1,096 samples

	Percentage (%) of samples
None of the residues HSE looked for	31.48%
Residues found at or below the MRL	65.51%
Residues above the MRL	3.01%

Great Britain fruit and vegetable results

For the Great Britain survey, the HSE Monitoring programme collected 1,360 samples of fruit and vegetables and tested for up to 413 pesticides.

HSE found 11 samples with residues above the MRL in the survey of imported beans with pods. This is consistent with previous years. Some of the beans are subject to additional testing at ports by local authorities and our findings are useful intelligence. HSE also found 8 MRL exceedances in surveys of peas with edible pods. The residues found were of isolated findings of different pesticides in imported produce. Suppliers were all informed.

HSE found chlorate with residues above the MRL in 5 samples in the survey of cauliflower and in 2 samples in the survey of carrots. The pesticide sodium chlorate is a residual broad action weed killer that is not authorised for use in the UK or EU. However, we are confident that the residues we are detecting come from use of chlorine based disinfectants used to maintain microbiological safety (to control microorganisms that cause food poisoning), either at food processing premises, or at public water works (chlorination) and not from use of pesticides used on plants. We are grateful for the information supplied by food producers and suppliers on this topic and, in particular, in response to our findings.

Biocides are important tools for maintaining microbiological food safety and any changes in practice to comply with current pesticide MRLs need to be carefully considered to ensure food safety is not compromised. HSE continues to work with companies to ensure compliance and safety in this area.

HSE reported a small number small number of instances of residues of linuron found in surveys of carrots. Although, linuron is not approved as a pesticide in Great Britain or the EU it can have potential for persistence in soils. HSE found in the survey of conference pears an instance of the residue diuron.

In 2023, HSE found no residues above the MRL in samples of kiwi fruit, onions, peas without pods and spring onions.

Great Britain fruit and vegetable results

The following results are for all the fruit and vegetables that we tested:

• 411 samples (30.22%) had none of the residues HSE looked for
• 908 samples (66.76%) had residues found at or below the MRL
• 41 samples (3.01%) had residues above the MRL

Great Britain survey, overall results for fruit and vegetables: 1,360 samples

	Percentage (%) of samples
None of the residues HSE looked for	30.22%
Residues found at or below the MRL	66.76%
Residues above the MRL	3.01%

Fruit and vegetables from the UK

The following results are for fruit and vegetables which were labelled as UK produced:

• 196 samples (42.61%) had none of the residues HSE looked for
• 252 samples (54.78%) had residues found at or below the MRL
• 12 samples (2.61%) had residues above the MRL

Great Britain survey, fruit and vegetables from the UK: 406 samples

	Percentage (%) of samples
None of the residues HSE looked for	42.61%
Residues found at or below the MRL	54.78%
Residues above the MRL	2.61%

Fruit and vegetables results by food type

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Beans with pods	96	42	11	28
Carrot	120	62	5	45
Cauliflower	96	37	5	9
Grapes	109	106	1	95
Kiwi fruit	96	53	0	14
Lemons	96	83	2	85
Onions	72	28	0	7
Oranges	96	86	6	91
Pears	97	83	1	79
Peas edible pods	59	36	5	30
Peas without pods	61	36	0	12
Pineapples	96	69	1	24
Potatoes	145	80	3	35
Soft Citrus	97	93	1	93
Spring onions	24	14	0	9

Great Britain starchy and cereal based food

For the Great Britain survey, the HSE monitoring programme collected 372 samples of starchy and cereal based food in 2023.

The Great Britain programme collected and analysed bread, rice and rye flour.

In 2023, HSE found no residues above the MRL in samples of bread, rice and rye flour.

The following results are for the Great Britain survey of starchy and cereal based foods:

• 105 samples (28.23%) had none of the residues HSE looked for
• 267 samples (71.77%) had residues found at or below the MRL
• none of the samples had residues above the MRL

Great Britain survey, overall results for starchy food and grain: 372 samples

	Percentage (%) of samples
None of the residues HSE looked for	28.23%
Residues found at or below the MRL	71.77%
Residues above the MRL	0

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Bread	216	208	0	116
Rice	84	38	0	22
Rye flour	72	21	0	15

Processing factors to find MRLs for bread (and other processed foods)

Apply to all traded foods, including foods used as ingredients. The law specifies the level applied to foods as they are traded. For almost all foods that means their raw, unprocessed form. But MRLs also apply to prepared and processed foods in which case the effect of processing needs to be taken into account.

To check that prepared and processed foods were made with ingredients that complied with MRLs, we use appropriate processing factors, based on scientific studies of the effect of preparation and processing. Different forms of processing remove, concentrate or dilute residues and the effect may also vary depending on the food and pesticide concerned.

The use of processing factors enables checks that the original ingredient was compliant with MRLs. Food manufacturers should have information on how they check their ingredients and on their recipes and preparation techniques – for instance, how much water is added or removed, or how much of an ingredient is used to make a food. We always contact them when there is possible non-compliance so that they can share their own information about processing factors.

Great Britain animal products results

For the Great Britain survey, the HSE monitoring programme collected 588 samples of animal products in 2023 including 96 samples of fish (oily).

Although included in our total figures above, we have not included the results for fish in the chart below as these foods have no MRLs, however of the 96 fish samples tested, 9 (9.37%) contained residues.

The British programme collected and analysed samples of fish (oily), liver, milk and poultry meat.

Most of the residues found in animal products were of BAC (benzalkonium chloride) or DDAC (dialkyldimethylammonium chloride) which are disinfectants widely used during food preparation, processing and butchery. Disinfectants are used for microbiological safety to control microorganisms that cause food poisoning.

We detected BAC in 5 samples of fish (oily), 5 samples of poultry meat and 2 samples of liver. HSE found BAC residues over the MRL in one sample of poultry meat and in one sample of liver. We found DDAC in one sample of fish (oily) and one sample of milk.

We found Dichlorodiphenyltrichloroethane (DDT) residues in 4 samples of fish (oily). Further information on this can be found below.

The following results are for the Great Britain survey of animal products excluding fish:

• 482 samples (97.97%) had none of the residues HSE looked for
• 8 samples (1.63%) had residues found at or below the MRL
• 2 samples (0.41%) had residues above the MRL

Great Britain survey, overall results for animal products: 492 samples

	Percentage (%) of samples
None of the residues HSE looked for	97.97%
Residues found at or below the MRL	1.63%
Residues above the MRL	0.41%

* symbol means that no MRLs are applied to fish.

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Fish (oily)*	96	9	0	1
Liver	96	3	1	0
Milk	300	1	0	0
Poultry meat	96	4	1	0

Dichlorodiphenyltrichloroethane(DDT)

The levels we found in fish (oily) would not be expected to have an effect on health, and overall are consistent with the continued decline of this pesticide in the environment.

The use of DDT is banned in the UK and banned or heavily restricted in many countries worldwide. It isn’t allowed for use on food crops anymore, but it is still used in some countries outside Europe as a public health insecticide. Residues of DDT take a long time to break down in the environment and can accumulate in fatty tissue which is a major reason that it has been banned in the UK, EU and many other countries.

Due to the bans and restrictions on use, the levels in food have decreased substantially since the 1960s and 1970s. Even so, because it takes a long time to break down, we do expect, and do see, occasional DDT residues in our monitoring results. Overall, the incidence and the size of residues have fallen steadily over time, which is what we would expect. In recent years none of our findings were unusual, unexpected or of concern.

The residues we find nowadays are at levels that would not be expected to have any effect on health.

For residues found in fish (oily) in 2023, we can tell from the chemical form detected by the laboratories whether the residues are from historic use. Historic use is indicated by the detection of DDE (dichlorodiphenyldichloroethylene) which is a break down product of DDT. All of the residues found were indicative of historic use.

Great Britain miscellaneous foods results

For the Great Britain survey, the HSE monitoring programme collected 254 samples of miscellaneous foods in 2023.

The Great Britain programme collected and analysed beans (dried), crisps (potato based), orange juice, pulses (dahl/lentils), snacks (cereal based) and snacks (speciality).

HSE found 7 samples with residues above the MRL in the survey of beans (dried). A follow up survey was put in place for 2024 programme.

The following results are for the Great Britain survey of miscellaneous foods:

• 126 samples (54.78%) had none of the residues HSE looked for
• 94 samples (40.87) had residues found at or below the MRL
• 10 samples (4.35%) had residues above the MRL

Great Britain survey, overall results for miscellaneous food: 254 samples

	Percentage (%) of samples
None of the residues HSE looked for	54.78%
Residues found at or below the MRL	40.87%
Residues above the MRL	4.35%

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Beans (dried)	72	34	7	25
Crisps (potato based)	24	16	0	3
Orange juice	48	8	0	5
Pulses (dahls/lentils)	24	17	2	15
Snacks (cereal based)	26	6	0	0
Snacks (speciality)	36	13	1	2

Great Britain infant food results

For the Great Britain survey, the HSE monitoring programme collected 24 samples of infant food in 2023. This year the infant food was all milk based.

Infant formula and infant food have their own MRLs which are set separately. Health departments are responsible for this legislation. However, these foods have been included in the UK’s national monitoring programme alongside other foods for many years and as part of the multi annual control plan.

The following results are for the Great Britain survey of infant food:

• all 24 samples (100%) had none of the residues HSE looked for
• none had residues found at or below the MRL
• none of the samples had residues above the MRL

Great Britain survey, infant food (fruit and vegetable) results: 24 samples

	Percentage (%) of samples
None of the residues HSE looked for	100%
Residues found at or below the MRL	0
Residues above the MRL	0

Residues over the MRL

All the Great Britain 2023 samples with residues over the MRL are listed in the Residues over the MRL table.

In each case HSE has written to the brand owner or the sampling point, asking for comments on how the residue occurred. We provide advice on how to prevent recurrence, including technical advice to assist in identifying the source of the residue where necessary. We offer the opportunity for brand owners or suppliers to arrange additional testing. All the information obtained is seen by the PRiF Committee before the results are published.

It is not possible to identify with absolute certainty the source or reason for every individual residue above the MRL. However, with the advice from the PRiF Committee and the cooperation of growers and brand owners we can identify some groups of results for which we think it is reasonable to reach a conclusion on both reasons for the breaches and some risk management decisions.

Chlorate

MRLs for chlorate recognise the crucial role of chlorate related compounds as biocides in water treatment and food hygiene. For most foods where residues are unavoidably incurred by such uses a footnote in the legislation allows HSE to waive the MRL, provided the producer supplies evidence that this is the case. In the cases identified as MRL breaches in this section no such evidence was supplied.

Beans with pods and LOD MRLs

Residues above the MRL do not necessarily mean the grower did not follow Good Agricultural Practice. A number of the MRLs have an asterisk (*) next to them, which means that the MRL is set at the limit of determination (the lowest level that can normally be detected by official laboratories).

This often means the pesticide has no authorised uses in the UK (or previously EU) on those crops. We cannot identify whether particular pesticides are authorised in other countries and so whether a residue is applied legally there. Provided the food meets the MRL requirements, it is legal to trade.

Anyone can apply for a higher MRL be set by HSE for trade in Great Britain. However, this needs to be supported with sufficient data or evidence for HSE to assess the suitability of the proposed MRL. This process may not be cost effective for some producers.

Residues over the MRL

Beans (dried) (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
1194/2023	Haricot beans	Canada	Fosetyl-Al (sum)	3.5	2*	No
1215/2023	Black eye beans	UK	Fosetyl-Al (sum)	3.4	2*	No
2630/2023	Mung beans	UK	fluroxypyr (partial sum)	0.05	0.01*	Yes
2635/2023	Black eye beans	USA	cypermethrin (sum)	0.07	0.05*	No
2635/2023	Black eye Beans	USA	dichlorvos	0.3	0.01*	Yes
2635/2023	Black eye Beans	USA	dimethoate	0.02	0.01*	No
2635/2023	Black eye Beans	USA	Fosetyl-Al (sum)	2.2	2*	No
2635/2023	Black eye Beans	USA	thiodicarb	0.02	0.01*	No
2746/2023	Cannellini beans	Argentina	Haloxyfop (alternate sum)	0.4	0.15	Yes
4068/2023	Black eye beans	UK	Chlorpyrifos	0.02	0.01*	No
4068/2023	Black eye beans	UK	Fosetyl-Al (sum)	2.5	2*	No
5162/2023	Cannellini beans	Argentina	Fosetyl-Al (sum)	44	2*	Yes

Beans with pods (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0001/2023	Valore beans	India	acetamiprid	0.8	0.6	No
0001/2023	Valore beans	India	dimethoate	0.9	0.01*	Yes
0001/2023	Valore beans	India	dithiocarbamates	2.5	1	Yes
0001/2023	Valore beans	India	omethoate	0.2	0.01*	Yes
0073/2023	Gawar beans with pods	India	diafenthiuron	0.08	0.01*	Yes
0073/2023	Gawar beans with pods	India	omethoate	0.05	0.01*	Yes
0077/2023	Papdi valor beans	India	dimethoate	0.5	0.01*	Yes
0077/2023	Papdi valor beans	India	omethoate	0.2	0.01*	Yes
0078/2023	Speciality gawar beans	India	omethoate	0.02	0.01*	Yes
0210/2023	Gwar beans	India	profenofos	0.04	0.01*	Yes
0212/2023	Gwar beans	India	thiophanate-methyl	0.3	0.1*	Yes
0342/2023	Yard long beans	India	flusilazole	0.05	0.01*	Yes
0342/2023	Yard long beans	India	omethoate	0.03	0.01*	Yes
0458/2023	Yard long beans	Thailand	bifenthrin	0.03	0.01*	Yes
0458/2023	Yard long beans	Thailand	diflubenzuron	0.06	0.01*	Yes
0458/2023	Yard long beans	Thailand	dimethomorph	0.3	0.01*	Yes
0458/2023	Yard long beans	Thailand	fipronil (sum)	0.07	0.005*	Yes
0458/2023	Yard long beans	Thailand	omethoate	0.2	0.01*	Yes
0458/2023	Yard long beans	Thailand	Prochloraz (sum)	0.1	0.03*	Yes
0458/2023	Yard long beans	Thailand	propiconazole	0.06	0.01*	Yes
0698/2023	Guar beans	India	thiophanate-methyl	0.3	0.1*	Yes
5784/2023	Yard long beans	India	dithiocarbamates	2.4	1	Yes
5784/2023	Yard long beans	India	profenofos	2.3	0.01*	Yes
6556/2023	Valore papdi beans	India	monocrotophos	0.2	0.01*	Yes

Carrots (Great Britain)

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0006/2023	Carrots	UK	linuron	0.05	0.01*	Yes
0036/2023	Carrots	Israel	linuron	0.03	0.01*	Yes
0183/2023	Carrots	UK	linuron	0.02	0.01*	Yes
2766/2023	Carrots	UK	chlorate	0.2	0.15	No
2941/2023	Carrots	UK	chlorate	0.2	0.15	No

Cauliflower (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0788/2023	Cauliflower rice	UK	chlorate	0.1	0.06	No
0789/2023	Cauliflower florets	UK	chlorate	0.07	0.06	No
1034/2023	Frozen cauliflower florets	UK	chlorate	0.08	0.06	No
5240/2023	Cauliflower florets	UK	chlorate	0.09	0.06	No
5644/2023	Cauliflower florets	UK	chlorate	0.2	0.06	Yes

Grapes (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0487/2023	Thompson Seedless Grapes	India	chlorpropham	0.03	0.01*	Yes

Lemons (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0287/2023	Verna lemons	Spain	imazalil	6.8	5	No
0681/2023	Lemons	South Africa	buprofezin	0.02	0.01*	Yes

Liver (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
1233/2023	Ox liver	UK	BAC (sum)	0.2	0.1	Yes

Oranges (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0320/2023	Valencia oranges	Egypt	cyfluthrin (sum)	0.03	0.02*	No
2271/2023	Blood oranges	South Africa	glufosinate (sum)	0.3	0.05	Yes
2333/2023	Valencia oranges	South Africa	chlorfenapyr	0.02	0.01*	Yes
5799/2023	Valencia oranges	Turkey	propiconazole	0.02	0.01*	Yes
5817/2023	Valencia delta seedless	South Africa	glufosinate (sum)	0.06	0.05	No
6558/2023	Late navel oranges	South Africa	ethephon	0.07	0.05*	No

Pears (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0396/2023	Conference Pears	UK	diuron	0.02	0.01*	Yes

Peas with edible pods s(Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0838/2023	Trimmed sugar snap peas	Kenya	chlorothalonil	0.09	0.01*	Yes
0900/2023	Trimmed sugar snap peas	Peru	fipronil (sum)	0.007	0.005*	No
0934/2023	Trimmed sugar snap peas	Kenya	chlorothalonil	0.08	0.01*	Yes
2915/2023	Tender and crisp mange tout	Peru	Chlorothalonil	0.03	0.01*	No
2915/2023	Tender and crisp mange tout	Peru	Iprodione	0.06	0.01*	Yes

Pineapples (Great Britain)

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
5161/2023	Tangy and Tropical Pineapple	Costa Rica	propiconazole	0.02	0.01*	5161/2023

Potatoes (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0016/2023	Maris piper potatoes	UK	flonicamid (sum)	0.1	0.09	No
5722/2023	Sagitta potatoes	UK	fosthiazate	0.06	0.02*	Yes
5722/2023	Sagitta potatoes	UK	fosthiazate	0.06	0.02*	Yes

Poultry Meat (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
3913/2023	Lean Turkey Mince	UK	BAC (sum)	0.3	0.1	Yes

Pulses (Great Britain)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
0931/2023	Red Split Lentils	UK	procymidone	0.2	0.01*	Yes
1121/2023	Red Lentils	UK	procymidone	0.02	0.01*	Yes

Soft Citrus (Great Britain)

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
2922/2023	Tangerines	South Africa	amitraz (sum)	0.1	0.05*	Yes

Analytical measurement uncertainty

No measurement can ever be guaranteed to be exact, this can be caused by many things. Measurement uncertainty is a calculated indicator of our confidence in the accuracy of the amount of pesticide the laboratory detected. It is not expressing a doubt about which pesticides we have found. It has been agreed for reporting purposes that measurement uncertainty will only be applied to any result that contained a residue over the MRL. In line with the international guidance, we use a default value of 50% for measurement uncertainty. This means that when a sample has a residue over the MRL we report the measured value but we determine which residues should be highlighted in the report as an exceedance by subtracting 50% of the reported result (for instance, 10 mg per kg becomes 5 mg per kg) and checking the adjusted value against the MRL. All residues still over the MRL after 50% measurement uncertainty has been applied, are highlighted as breaching the law in our quarterly reports.

Measurement uncertainty can only be applied by a regulatory authority. In the UK, this role is taken on by HSE. It should not be applied by the food industry to determine whether a product is compliant with an MRL.

Part 3: Results from the Northern Ireland programme

Overall results

In 2023, HSE tested 1,073 samples from 25 different food surveys sampled in 4 towns in Northern Ireland and analysed for up to 306 different pesticides. All samples were collected only from retail sources.

Some food that is produced in Northern Ireland is specifically labelled as product of Northern Ireland, but most is labelled as UK produced. The results therefore distinguish between UK and non UK labelled food.

The following results summarise all the Northern Ireland surveys:

• 556 samples (51.82%) had none of the residues HSE looked for
• 512 samples (47.72%) had residues at or below the MRL
• 5 samples (0.47%) had residues over the MRL

Northern Ireland survey, overall results 2023: 1,073 samples

	Percentage (%) of samples
None of the residues HSE looked for	51.82%
Residues found at or below the MRL	47.72%
Residues above the MRL	0.47%

Food from the UK

The following results are for Northern Ireland surveys labelled as UK produced:

• 348 samples (70.16%) had none of the residues HSE looked for
• 147 samples (29.64%) had residues found at or below the MRL
• one sample (0.20%) had residues above the MRL

Northern Ireland survey 2023, food from the UK: 496 samples

	Percentage (%) of samples
None of the residues HSE looked for	70.16%
Residues found at or below the MRL	29.64%
Residues above the MRL	0.20%

Food from outside the UK

The following results are for Northern Ireland surveys labelled as produced outside of the UK:

• 208 samples (36.05%) had none of the residues HSE looked for
• 365 samples (63.26%) had residues found at or below the MRL
• 4 Samples (0.69%) had residues above the MRL

Northern Ireland survey, food from outside the UK: 577 samples

	Percentage (%) of samples
None of the residues HSE looked for	36.05%
Residues found at or below the MRL	63.26%
Residues above the MRL	0.69%

Northern Ireland fruit and vegetable results

For the Northern Ireland survey, the HSE Monitoring programme collected 686 samples of fruit and vegetables and tested for up to 401 pesticides.

HSE found 2 samples with residues above the MRL, one in oranges and peas edible pods.

The following results are for all the fruit and vegetables that were tested:

• 262 samples (38.19%) had none of the residues HSE looked for
• 421 samples (61.37%) had residues found at or below the MRL
• 3 samples (0.44%) had residues above the MRL

Northern Ireland survey, overall results for fruit and vegetable: 686 samples

	Percentage (%) of samples
None of the residues HSE looked for	38.19%
Residues found at or below the MRL	61.37%
Residues above the MRL	0.44%

Fruit and vegetables from the UK

The following results are for fruit and vegetables which were labelled as UK produced:

• 317 samples (77.89%) had none of the residues HSE looked for
• 90 samples (22.11%) had residues found at or below the MRL
• none of the samples had a residue above the MRL

Northern Ireland survey, fruit and vegetable from the UK: 407 samples

	Percentage (%) of samples
None of the residues HSE looked for	77.89%
Residues found at or below the MRL	22.11%
Residues above the MRL	0%

Fruit and vegetables results by food type

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Beans with pods (Northern Ireland)	39	27	1	13
Brussel Sprouts (Northern Ireland)	22	15	0	3
Carrot (Northern Ireland)	44	8	0	2
Cauliflower (Northern Ireland)	45	3	0	0
Grapes (Northern Ireland)	46	43	0	39
Kiwi fruit (Northern Ireland)	49	25	0	7
Lemons (Northern Ireland)	41	27	0	36
Onions (Northern Ireland)	47	10	0	6
Oranges (Northern Ireland)	44	41	1	41
Pears (Northern Ireland)	44	39	0	27
Peas edible pods (Northern Ireland)	27	22	1	15
Peas without pods (Northern Ireland)	21	11	0	0
Pineapples (Northern Ireland)	43	19	0	5
Potatoes (Northern Ireland)	69	35	0	7
Soft citrus (Northern Ireland)	56	64	0	52
Spring onions (Northern Ireland)	48	32	0	25

Northern Ireland starchy food and grain results

For the Northern Ireland survey, the HSE monitoring programme collected 122 samples of starchy food and grains in 2023.

The Northern Ireland programme collected and analysed bread (bread was not collected in quarter 1), rice and rye flour.

HSE found no residues above the MRL in the samples tested.

The following results are for the Northern Ireland survey of starchy food and grain:

• 56 samples (45.90%) had none of the residues HSE looked for
• 66 samples (54.10%) had residues found at or below the MRL
• none of the samples had residues above the MRL

Northern Ireland survey, results for starchy food and grain: 122 samples

	Percentage (%) of samples
None of the residues HSE looked for	45.90%
Residues found at or below the MRL	54.10%
Residues above the MRL	0%

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Bread	57	50	0	4
Rice	42	15	0	10
Rye flour	23	1	0	1

Processing factors to find MRLs for bread (and other processed foods)

Apply to all traded foods, including foods used as ingredients. The law specifies the level to apply to foods as they are traded. For almost all foods that means their raw, unprocessed form. But, MRLs also apply to prepared and processed foods in which case the effect of processing needs to be taken into account.

To check that prepared and processed foods were made with ingredients that complied with MRLs, we use appropriate processing factors, based on scientific studies of the effect of preparation and processing. Different forms of processing remove, concentrate or dilute residues, and the effect may also vary depending on the food and pesticide concerned.

The use of processing factors enables checks that the original ingredient was compliant with MRLs. Food manufacturers should have information on how they check their ingredients and on their recipes and preparation techniques – for instance, how much water is added or removed, or how much of an ingredient is used to make a food. We always contact them when there is possible non- compliance so that they can share their own information about processing factors

Northern Ireland animal products results

For the Northern Ireland survey, the HSE monitoring programme collected 168 samples of animal products in 2023.

The Northern Ireland programme collected and analysed fish (oily), liver (bovine) (samples collected in quarter 2 and 3), milk and poultry meat.

Although included in our total figures above we have not included the results for fish in the chart below as these foods have no MRLs however, of the 48 fish samples tested 13 (27.08%) contained residues including one sample with residues of BAC.

The following results are for the Northern Ireland survey of animal products excluding fish:

• 164 samples (97.62%) had none of the residues HSE looked for
• 4 samples (2.38%) had residues found at or below the MRL
• none of the samples had residues above the MRL

Northern Ireland survey, overall results for animal products: 168 samples

	Percentage (%) of samples
None of the residues HSE looked for	97.62%
Residues found at or below the MRL	2.38%
Residues above the MRL	0%

* symbol used indicates there are no MRLs are applied to fish.

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Fish (oily)	48	13	0	0
Liver	48	3	0	0
Milk	72	0	0	0
Poultry meat	48	1	0	1

DDT

This year we found DDT in 12 samples of fish. The levels we found would not be expected to have an effect on health, and overall are consistent with the continued decline of this pesticide in the environment.

The use of DDT is banned in the UK and banned or heavily restricted in many countries worldwide. It isn’t allowed for use on food crops anymore, but it is still used in some countries outside Europe as a public health insecticide. Residues of DDT take a long time to break down in the environment and can accumulate in fatty tissue which is a major reason that it has been banned in the UK, EU and many other countries.

Due to the bans and restrictions on use, the levels in food have decreased substantially since the 1960s and 1970s. Even so, because it takes a long time to break down, we do expect, and do see, occasional DDT residues in our monitoring results. Overall, the incidence and the size of residues have fallen steadily over time, which is what we would expect. In recent years none of our findings were unusual, unexpected or of concern.

The residues we find nowadays are at levels that would not be expected to have any effect on health.

For residues found in fish in 2023, we can tell from the chemical form detected by the laboratories whether the residues are from historic use (which is what we usually find). Historic use is indicated by the detection of DDE which is a break down product of DDT. PRiF explain this every time DDT detections are published to try to make it as clear as they can that the results show food producers are not using DDT today. However, there are occasional media stories about DDT and various links and associations, which do not make this distinction.

Northern Ireland miscellaneous foods results

For the Northern Ireland survey, the HSE monitoring programme collected 37 samples of Beans (dried) in 2023.

The following results are for the Northern Ireland survey of Beans (dried):

• 27 samples (72.97%) had none of the residues HSE looked for
• 8 samples (21.62%) had residues found at or below the MRL
• 2 samples (5.41%) had residues above the MRL

Northern Ireland survey, results for miscellaneous food: 37 samples

	Percentage (%) of samples
None of the residues HSE looked for	72.97%
Residues found at or below the MRL	21.62%
Residues above the MRL	5.41%

Food sampled	Number of samples tested	Number of samples containing residues at or below MRL	Number of samples containing residues above the MRL	Number of samples containing more than one pesticide
Beans (dried)	37	8	2	4

Northern Ireland infant food results

For the Northern Ireland survey, the HSE monitoring programme collected 12 samples of infant food in 2023.

Infant food and infant formula have their own MRLs which are set separately. Health departments are responsible for this legislation. However, these foods have been included in the UK’s national monitoring programme alongside other foods for many years and as part of the multi annual control plan.

The following results are for the Northern Ireland survey of infant food:

• 12 samples (100%) contained none of the pesticides HSE looked for
• none of the samples had residues found at or below the MRL
• none of the samples had residues above the MRL

Residues over the MRL

All the Northern Ireland 2023 samples with residues over the MRL are listed in the Residues over the MRL table.

In each case HSE has written to the brand owner or the sampling point, asking for comments on how the residue occurred. We provide advice on how to prevent recurrence, including technical advice to assist in identifying the source of the residue where necessary. We offer the opportunity for brand owners or suppliers to arrange additional testing. All the information obtained is seen by the PRiF before the results are published.

It is not possible to identify with absolute certainty the source or reason for every individual residue above the MRL, particularly when isolated findings. However, with advice from the PRiF and the cooperation of growers and brand owners we can identify some groups of results for which we think it is reasonable to reach a conclusion on both reasons for the breaches and some risk management decisions.

The most frequent non compliant samples were in the barley survey. Three samples contained residues of fosetyl (sum). The residues were detected as phosphonic acid: like similar findings in Great Britain. HSE considers it likely the residues are from use of fertilisers or other non-PPP products.

Residues over the MRL

Beans (dried) (Northern Ireland)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
2672/2023	Haricot beans	Canada	fosetyl-Al (sum)	8.9	2*	Yes
4180/2023	Chick peas	UK	2,4-D (sum)	0.36	0.05*	Yes

Beans with pods (Northern Ireland)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
6630/2023	Fine beans	Kenya	dimethomorph	0.016	0.01*	No

Oranges (Northern Ireland)

* symbol indicates LOD MRL.

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
1431/2023	Oranges	Egypt	acrinathrin	0.031	0.02*	No

Peas edible pods (Northern Ireland)

Sample ID	Food type	Country of origin	Pesticide detected	Residue detected (mg per kg)	MRL (mg per kg)	MRL exceedance after allowing for measurement uncertainty
1518/2023	Sugar snap peas	Guatemala	chlorothalonil	0.35	0.01	Yes

Analytical measurement uncertainty

No measurement can ever be guaranteed to be exact, this can be caused by many things. Measurement uncertainty is a calculated indicator of our confidence in the accuracy of the amount of pesticide the laboratory detected. It is not expressing a doubt about which pesticides we have found. It has been agreed for reporting purposes that measurement uncertainty will only be applied to any result that contained a residue over the MRL. In line with the international guidance, we use a default value of 50% for measurement uncertainty. This means that when a sample has a residue over the MRL we report the measured value but we determine which residues should be highlighted in the report as an exceedance by subtracting 50% of the reported result (for instance, 10 mg per kg becomes 5 mg per kg) and checking the adjusted value against the MRL. All residues still over the MRL after 50% measurement uncertainty has been applied are highlighted as breaching the law in our quarterly reports.

Measurement uncertainty can only be applied by a regulatory authority. In the UK, this role is taken on by the HSE. It should not be applied by the food industry to determine whether a product is compliant with an MRL.

Annex 1 – Laboratory quality control

The samples collected in 2023 for each survey were analysed at one of 4 official laboratories.

Ordinarily each laboratory tests all the samples for a survey. Sending all the samples of one type to one laboratory gives economies of scale for the programme as well as enabling laboratories to develop or improve analytical methodology within particular areas.

For samples collected in Northern Ireland, the official laboratory must be located in either Northern Ireland or in the EU.

Each laboratory is accredited by the UK Accreditation Service (UKAS) to ISO/IEC 17025:2017 for the analyses performed.

Each laboratory is required to take part in independent proficiency tests relevant to the monitoring programme and share their scores with HSE. During 2023 all 4 laboratories took part in relevant proficiency testing organised by the EU Reference Laboratory.

During 2023, the laboratories were required to follow the Analytical Quality Control and Method Validation Procedures for Pesticide Residues Analysis in Food and Feed.

Laboratory	Testing accreditation number
SASA, Edinburgh	1406 UKASa
Fera Science Ltd, York	1642 UKASa (the national accreditation body for the United Kingdom)
Agri Food and Biosciences Institute (AFBI), Belfast	2632 UKASa
SCL, Paris	10527 rev 22 Cofrac (the French committee for accreditation)