Research and analysis

RIFE 30 Technical Summary, Radioactivity in Food and the Environment, 2024

Updated 30 October 2025

Technical summary

This section is divided into the following topics to highlight the scope of this report:

• radiation exposures (doses^{[footnote 1]}) to people living near UK nuclear licensed sites
• radioactivity concentrations in samples collected near UK nuclear licensed sites
• external dose rates measured near UK nuclear licensed sites
• UK nuclear licensed site incidents and non-routine surveys
• habits surveys near UK nuclear licensed sites
• monitoring of radioactivity at locations remote from UK nuclear licensed sites (overseas incidents, non-nuclear sites and regional monitoring across the UK)
• the environmental radioactivity monitoring programmes

Radiation exposure (doses) to people living near UK nuclear licensed sites

Radiation doses^{[footnote 1]} to people living near nuclear licensed sites are assessed using data from radiological monitoring programmes, which cover both food and the environment. Radionuclide concentrations, dose rates, and information on the habits of people living near the sites are used to estimate doses. Where monitoring data were not available, some environmental concentrations were estimated by environmental transfer modelling of reported discharges. People’s exposure to radiation (doses) can vary from year to year, due to changes in radionuclide concentrations and external dose rates. Changes in habits data and information, in particular food consumption, can also cause the estimates of dose to vary.

The dose quantity presented in this summary is known as the ‘total dose’. This is made up of contributions from all sources of radioactivity from anthropogenic processes. Source specific dose assessments are also carried out in some cases to provide additional information and to compare with the ‘total dose’ assessment method.

Figure TS, shows the ‘total dose’ in 2024 (as bars) across the UK, ranging from less than 0.005mSv to 0.22mSv in comparison to the dose limit to members of the public, the blue bar. Table S contains the numerical values of the ‘total dose’ presented in Figure TS and includes the major contributors to dose. The ‘total dose’ is due to the combined effects of authorised or permitted waste discharges and direct exposure from the site (‘direct radiation’) on those people most exposed to radiation near all nuclear licensed sites in the UK.

Figure TS. ‘Total dose’, in mSv y^-1, in the UK due to radioactive waste discharges and direct radiation, 2024 (Exposures to the Cumbrian Coastal Community receive a significant contribution to the dose from historical discharges of naturally occurring radionuclides from the former phosphate processing plant at Whitehaven).

Site	Dose, mSv y-1
Capenhurst	0.22
Cumbrian Coastal Community	0.20
Grove Centre, Amersham	0.087
Barrow	0.061
Dounreay	0.021
Springfields	0.017
Heysham	0.016
Winfrith	0.015
Hinkley	0.014
Sizewell	0.014
Rosyth	0.011
Torness	0.011
Aldermaston and Burghfield	0.010
Dungeness	0.010
Trawsfynydd	0.010
Harwell	0.008
Wylfa	0.008
Chapelcross	0.007
Derby	0.007
Hartlepool	0.007
Hunterston	0.006
Berkeley and Oldbury	0.005
Bradwell	0.005
Devonport	0.005
Faslane	0.005
Dose limit	1.0

Doses to individuals are determined for those people most exposed to radiation, these individuals are known as a ‘representative person’^{[footnote 2]}. The estimated doses are compared with legal limits for the public. The method used to calculate doses to a representative person is based on guidance from the National Dose Assessment Working Group (NDAWG)(National Dose Assessment Working Group 2008). NDAWG guidance proposes developing a series of habits profiles of people living and consuming food grown (or sourced) near nuclear sites. These are derived from the habits survey data. Each habits profile provides information on an individual’s food consumption and occupancy rates. Doses for each habits profile are calculated, and the ‘representative person’ is that profile which receives the highest dose.

In 2024, radiation doses from authorised or permitted releases of radioactivity to people living around nuclear licensed sites, remained well below the UK national limit of 1 millisievert (mSv, a measure of dose) per year (see Appendix 2 for explanation of dose units).

The locations where the public received the highest doses in 2024 were: Capenhurst (0.22mSv), the Cumbrian coastal community^{[footnote 3]} near Sellafield (0.20mSv), and the Grove Centre, Amersham (0.087mSv). The dose at Capenhurst increased from 0.15mSv in 2023, this is due to a higher estimate of direct radiation, which is the dominant contribution to doses to the public from this site. The dose received near the Grove Centre, Amersham was also dominated by direct radiation.

Doses to the Cumbrian coastal community receive contributions from a variety of sources in the area. The highest dose to the Cumbrian coastal community near Sellafield was mostly due to historical liquid discharges. In 2024, the representative person from the Cumbrian coastal community, was a high-rate crustacean consumer (who also consumed significant quantities of other seafood) and was unchanged from 2023. The estimated dose was 0.20mSv in 2024. Most of this dose (0.18mSv) was due to historical discharges of naturally occurring radioactive radionuclides (Naturally Occurring Radioactive Material) from the former phosphate processing plant near Whitehaven. The remainder of the dose (0.018mSv) was due to the permitted discharges of artificial radionuclides by Sellafield and the Low Level Waste Repository (LLWR) and includes a contribution from sources of direct radiation on the LLWR site. For 2023, the representative person received a dose of 0.23mSv (including a contribution of 0.21mSv and 0.019mSv related to historical discharges from the former phosphate processing plant and discharges from Sellafield and the LLWR, respectively). The decrease in ‘total dose’ was mostly attributed to the lower concentrations of polonium-210 in lobsters. The largest contribution to dose to seafood consumers in the Cumbrian coastal community was from the radionuclide polonium-210.

Polonium-210 can be a significant contributor of the dose to the most exposed members of the public because it has a relatively high dose coefficient (a factor used to convert an intake of radioactivity into a radiation dose) identified by the International Commission on Radiological Protection (ICRP). In the Cumbrian coastal area polonium-210 is present in the environment from natural sources and from Naturally Occurring Radioactive Material (NORM) from the former phosphate processing plant at Whitehaven. Polonium-210 concentrations in crustacean samples continued to be within or close to the expected range from these natural sources in 2024. The discharge effects from the Sellafield site and the former phosphate processing plant (near Whitehaven) both impact the same area and therefore the contributions to doses from both sources are considered in Section 3.3.1 in the main report.

In Scotland, the representative person consuming food produced on land near Dounreay received the highest ‘total dose’ from authorised releases of radioactivity. The dose to adults was 0.021mSv in 2024, a decrease from 2023 (0.028mSv).

The highest dose in Wales was near the Trawsfynydd nuclear power station, which is being decommissioned. The representative person was a consumer of locally produced foodstuffs, and the dose was primarily due to historical permitted discharges from the site. The source specific dose^{[footnote 4]} to 1-year-old infants was 0.037mSv in 2024; a slight increase from 2023 (0.034mSv).

Radioactivity concentrations in samples collected near UK nuclear sites

There were no major variations in environmental concentrations of radioactivity in 2024 compared to those in 2023. Near Sellafield, the environmental concentrations of most radionuclides have declined over the past 3 decades, albeit much more slowly in recent years.

In 2018, a review of the 2009 UK Radioactive Discharge strategy was published (Department for Business Energy and Industrial Strategy 2018). The review demonstrates clear evidence of progress being made by the UK in meeting the outcomes of the 2009 strategy and contributing towards the objectives of the OSPAR^{[footnote 5]} radioactive substances strategy (RSS). Specifically, significant progress has been made towards achieving progressive and substantial reductions in radioactive discharges. As a result of the decrease in discharges, there has been a reduction in the concentrations of radionuclides in the marine environment and subsequently a reduction the in exposures of people to ionising radiation (see appendix 2) (OSPAR 2022).

The OSPAR Radioactive Substances Committee published its Fifth Periodic Evaluation in 2022, which demonstrated that Contracting Parties, including the UK, have successfully fulfilled the objectives of the OSPAR RSS for 2020 under the North-East Atlantic Environment Strategy (NEAES) 2010 – 2020 and have made significant progress against the ultimate aim of radionuclide concentrations in the environment near background values for naturally occurring radionuclides and close to zero for artificial radionuclides (see Section 1.3.2 in the main report for further details) (OSPAR 2022). The UK specific outcomes in the fifth periodic evaluation (see Annex 2, (OSPAR 2022)), reinforces the findings of the 2018 review of the 2009 UK strategy for radioactive discharges.

External dose rates measured near UK nuclear sites

Radioactivity in sediments in intertidal areas can potentially contribute to the total radiation exposure to members of the public. For this reason, in situ measurements of radiation dose rates are taken over exposed areas of sediment. These ‘external doses’ are included in the assessment of doses to the public where they are higher than natural background rates. To determine the dose to the public from any radioactivity that may be present because of authorised or permitted discharges, natural background rates are subtracted from the measured dose rates in the assessment.

There were no major changes in external dose rates in intertidal areas in 2024 compared with 2023. At most locations, the external dose rates were close to background rates. Rates were higher in some estuaries near Sellafield (up to twice the background rate) and in the Ribble Estuary, which is in the Eastern Irish Sea.

UK nuclear sites incidents and non-routine surveys

During 2024, as a result of an ongoing programme of monitoring by Sellafield Limited, radioactive items (particles and objects^{[footnote 6]}) from Sellafield were detected on Cumbrian beaches and removed (51 in the 2024 calendar year). The advice from the UK Health Security Agency (UKHSA) and the Food Standards Agency (FSA) is that the risk to the public from the radioactive particles and larger objects found on West Cumbrian beaches is very low. A programme of work is in place to meet the primary aim of providing reassurance that overall risks to beach users remain at, or below, those estimated in the UKHSA risk assessment. UKHSA published a summary report of assessing the risk to people’s health from radioactive objects on beaches around the Sellafield site in February 2020 (Oatway, Cabianca & Jones 2020).

At Dounreay, the comprehensive beach monitoring programme continued for fragments of irradiated nuclear fuel (particles). Last year, the number of particles recovered and the range in radioactivity content were similar to that observed in recent years. Fishing restrictions in a specific area around Dounreay are still in force under the Food and Environment Protection Act (FEPA) 1985 (United Kingdom - Parliament 1985).

Special (or ‘ad hoc’) sampling related to nuclear licensed site operation is carried out at sites when needed or to provide one-off data sets. No such need arose in 2024.

Habits surveys near UK nuclear sites

For ‘total dose’ assessments, habits data are used to define one or more hypothetical individuals^{[footnote 7]} (for each pathway). The doses to each hypothetical individual are calculated and the individual with the highest dose is the representative person. The dose calculated in this way is considered representative of the dose to the most highly exposed individuals in the population.

In 2024, the regular programmes of habits surveys continued using existing methods. Surveys were carried out at Hartlepool, Hinkley Point, and Sellafield in England, and at Hunterston and along the Dumfries and Galloway coast in Scotland.

These habits surveys give site-specific information on the diet and occupancy habits of people near nuclear sites. The findings were used to confirm the adequacy of current monitoring programmes, to strengthen and update them with a better representation of relevant exposure pathways, and to improve the assessment of doses to members of the public near nuclear sites.

Monitoring of radioactivity at locations remote from UK nuclear sites

Monitoring in the UK and surrounding seas was carried out to assess the impact of (1) non-nuclear sites, (2) the concentrations of radioactivity across the UK (measured as part of the regional monitoring programme) and (3) overseas incidents that may have introduced radioactivity into the environment.

Non-nuclear sites

In the past, liquid waste slurry (regarded as NORM) containing thorium and uranium was discharged from the former phosphate processing plant near Whitehaven into the Irish Sea. These discharges have resulted in an increase in the concentrations of naturally occurring radionuclides in the environment through the production of radioactive decay products (from the radioactive decay of radionuclides previously discharged to sea).

Historically, the concentrations of lead-210 (and polonium-210, discussed previously), in fish and shellfish (near Whitehaven) have been found to be higher than the maximum expected concentration ranges due to naturally occurring radioactivity. Estimates of the enhanced concentrations in seafood are made by subtracting the median of the expected natural concentration range of these radionuclides from the measured values. These radionuclides are important in that small changes in values above background, significantly influence their contribution to the combined dose.

Tritium was detected in the leachate from some solid waste disposal sites at low levels. There are authorised and permitted disposal routes which enable the disposal of waste to a solid waste disposal facility that can contain tritium. For example, contaminated personal protective equipment or sampling equipment from hospitals and industrial sites or due to disposals of gaseous tritium light devices (such as fire exit signs) from public and commercial buildings.

Work to address radioactive contamination is ongoing at Dalgety Bay, Fife. Public protection measures have been established, and these were maintained during 2024 and into 2025. This includes continuing a monthly beach monitoring and particle recovery programme. The FEPA Order issued by Food Standards Scotland (FSS) (then FSA in Scotland), prohibiting the collection of seafood from the Dalgety Bay area, remains in force. The remediation contract was awarded by the Ministry of Defence (MOD) in February 2020 and an Environmental Authorisations (Scotland) Regulations (EASR18) permit for the required work was granted in May 2021. Remediation work took place between 2021 and 2023. The area will now undergo a period of evaluation to assess if the remedial works have been successful.

Further details can be found in Section 7.7 of this report and on the radioactive substances pages of Scottish Environmental Protection Agency (SEPA’s) website: SEPA Dalgety Bay.

Regional monitoring of radioactivity across the UK

Regional monitoring in areas remote from nuclear licensed sites continued in 2024 to:

• establish the extent of long-distance transport of radioactivity from UK and other nuclear sites
• identify any general contamination of the food supply and the environment
• provide data in compliance with UK obligations under the OSPAR Convention

Monitoring of artificial radioactivity in Northern Ireland, is undertaken primarily to assess the long-distance transport of radioactivity historically discharged from Sellafield. Consumer doses in Northern Ireland were estimated to be less than 1% of the annual limit of 1mSv for members of the public in 2024. A survey on the Channel Islands confirmed that doses due to discharges from the French reprocessing plant at La Hague and other local sources were less than 0.5% of the legal limit.

Food and sources of public drinking water that make up a general diet for people were analysed for radioactivity across the UK. In 2024, artificial radionuclides only contributed a small proportion of the total public radiation dose in people’s general diet, and this was much less than 0.5% of the legal limit.

The distribution of radionuclides in coastal seas continues to be monitored remote from nuclear sites. This supports the UK’s marine environmental policies and international treaty commitments. Government research vessels are used in the sampling programme, and the results have been used to show trends in the quality of the UK’s coastal seas. These surveys, together with the results of monitoring at nuclear sites, contribute to the UK data submitted to the OSPAR Commission. These data also help measure progress towards the UK government and devolved administrations objectives for improving the state of the marine environment, through the UK’s Marine Strategy, particularly Descriptor 8 – Contaminants. More information on Descriptor 8 can be found at Marine online assessment tool - radionuclides.

Overseas incidents

The accident at the Fukushima Dai-ichi nuclear power station in Japan in March 2011 resulted in significant quantities of radioactivity being released. Subsequent controls on imported food and animal feed products from Japan to the UK mainland were revoked in June 2022. The European Union (EU) revoked their controls in July 2023.

Screening instruments are used at importation points of entry to the UK as a general check on possible contamination from unknown sources. One example of how these screening instruments can be triggered occurred at Dover, when the presence of caesium-137 was detected in a consignment of food being brought into the UK. A sample of dried blueberry powder was analysed, and the activity concentration was 396Bq kg^-1. At this concentration, Food Standards Agency considered that there was no food safety requirement to limit their placement on the market for human consumption.

The environmental radioactivity monitoring programmes

The environmental monitoring programmes in this report are carried out on behalf of the Environment Agency, FSA, FSS, Natural Resources Wales (NRW), Northern Ireland Environment Agency (NIEA) and SEPA and are independent of the industries discharging radioactive wastes. The programmes include monitoring in support of the Scottish Government, Channel Island states, Department of Agriculture, Environment and Rural Affairs (DAERA), Department for Energy Security & Net Zero (DESNZ), Department for Environment, Food & Rural Affairs (Defra), NRW and the Welsh Government. The monitoring programmes involve specialist laboratories working together, each with rigorous quality assurance procedures, and a wide range of sample collectors throughout the UK.

Overall, around 10,000 analyses and dose rate measurements were completed in 2024. The analytical results of the environmental radioactivity monitoring programmes are reported in tables in the relevant sections (Sections 3 to 8 of the main report). The values provided in the tables are given in 3 different forms,

• measurable values (referred to as ‘positively detected’)
• less than values (that is, the lowest activity concentration, or dose rate measurement, that can be reliably detected for a given analytical method)
• not detected (ND) values (meaning that insufficient evidence is available to determine the existence of a radionuclide)

More information about the programmes described in this report is available from the sponsoring agencies. Their contact details can be found at the end of the Foreword of this report. The results of the analysis of food samples collected near nuclear sites in England and Wales are published on the FSA’s data portal (FSA data catalogue - monitoring data).

References

Department for Business Energy and Industrial Strategy, 2018, UK strategy for radioactive discharges; 2018 Review of the 2009 Strategy, London.

International Commission on Radiological Protection, 2007, The 2007 Recommendations of the International Commission on Radiological Protection, vol. 37.

National Dose Assessment Working Group, 2008, NDAWG GUIDANCE NOTE 1 Overview of guidance on the assessment of radiation doses from routine discharges of radionuclides to the environment.

Oatway, W., Cabianca, T. & Jones, A., 2020, Assessing the risk to people’s health from radioactive objects on beaches around the Sellafield site Summary report. PHE-CRCE-056, Chilton.

OSPAR, 2022, Towards the Radioactive Substances Strategy Objectives. Fifth Periodic Evaluation., London.

United Kingdom - Parliament, 1985, Food and Environment Protection Act 1985.

Abbreviations

See Appendix 2 of the main report.

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Technical Summary Footnotes

1. The monitoring results in this report are interpreted in terms of radiation exposures of the public, commonly termed ‘doses’. ↩ ↩²

2. International Commission on Radiological Protection recommendations (International Commission on Radiological Protection 2007) use the term ‘representative person’ for assessing doses to members of the public. It is defined as ‘an individual receiving a dose that is representative of the more highly exposed individuals in the population’. Radioactivity in Food and the Environment reports published before 2013 referred to an average dose to individuals in a group of people (the ‘critical group’) rather than to a single person. The ‘representative person’ concept is considered equivalent to the ‘critical group’. ↩

3. The Cumbrian coastal community are exposed to radioactivity resulting from current and historical discharges from the Sellafield site, the Low Level Waste Repository (LLWR) and historical discharges of naturally occurring radionuclides from the former phosphate processing plant near Whitehaven. ↩

4. See Section 1.2, Appendix 2 and Appendix 5 of the main report for more information. ↩

5. The Oslo and Paris Convention for the protection of the marine environment of the North-East Atlantic. ↩

6. ‘Particles and objects’ are terms used which encompass discrete radioactive items which can range in radioactivity concentration, size and origin. ‘Particles’ include radioactive scale, fragments of irradiated nuclear fuel and incinerated waste materials (less than 2mm in diameter). ‘Objects’ are larger radioactive artefacts and stones which have radioactive contamination on their surface and are larger than 2mm in size. ↩

7. A hypothetical individual is used in radiological dose assessments as it is often not possible to identify a specific member of a population whose habits are likely to result in them receiving a dose towards the upper end of the range seen in that population when variability and uncertainty in exposure pathways and source of radiation are considered. Use of the concept of the representative person has been recommended by the ICRP and UKHSA as a practical approach to assess the radiological impact of exposure to a source of radiation. ↩