Radionuclides
Natural levels of radioactivity in food are extremely low. Under normal circumstances there are no prescribed limits for radionuclides in food. However, in the event of a nuclear accident or radiological emergency, regulations are in place to ensure food safety.
If a radiological emergency occurs, assimilated EU Regulation 2016/52 becomes active in England, Scotland, and Wales. The relevant regulation in Northern Ireland is Regulation (Euratom) 2016/52. These regulations require UK authorities to enforce maximum permitted levels of radionuclides in food to protect public health.
The maximum permitted levels are set no higher than the following levels:
|
Nuclides |
Maximum permitted level (Bq/kg) |
|
Isotopes of strontium, notably Sr-90 |
750 |
|
Isotopes of iodine, notably I-131 |
2000 |
|
Alpha-emitting isotopes of plutonium and transplutonium elements, notably Pu-239 and Am-241 |
80 |
|
All other nuclides of half-life greater than 10 days, notably Cs-134 and Cs-137 |
1250 |
The UK authorities have an obligation to keep the new maximum radionuclide levels under review and to amend them as appropriate.
There are 2 further Regulations that cover the radioactive contamination of foods:
- Assimilated EU Regulation 2219/89 lays down the conditions for exporting food and feed after a nuclear accident or radiological emergency in England, Scotland, and Wales. Food and feed with levels of radioactive contamination that exceeds permitted levels may not be exported. The equivalent regulation in Northern Ireland is Regulation (EEC) 2219/89.
- Assimilated EU Regulation 2020/1158 applies in England, Scotland, and Wales to imports of food and feed originating in third countries that are affected by the Chernobyl accident. The equivalent regulation in Northern Ireland is Regulation (EU) 2020/1158. The Regulation doesn’t apply to fishery products or live bivalve molluscs.
Special measures following Fukushima
Following the 2011 Fukushima nuclear incident, the EU introduced enhanced import controls on food originating from affected areas in Japan. After a review of the enhanced controls in 2022, the UK determined that these additional measures were no longer necessary, as general food safety laws provide sufficient protection. As a result, the UK removed these restrictions.The EU lifted its restrictions on food from Japan in August 2023.
Monitoring radioactivity in the UK
Major producers of radioactive waste in the UK are required to monitor the environment around their premises. The following organisations work together on monitoring programmes to measure radioactivity in the environment and in food:
- Environment Agency
- Food Standards Agency
- Northern Ireland Environment Agency
- Natural Resources Wales
- Scottish Environment Protection Agency
Their results are published annually in the Radioactivity in Food and the Environment (RIFE) report, which provides a clear assessment of any potential risks to public health.
More information about radioactivity in food can be found here:
- Food Standards Agency: Radioactivity in food
- GOV.UK: Monitoring radioactivity
- GOV.UK: Radioactivity in food and the environment (RIFE) report
How safe are the limits?
The levels set in assimilated EU Regulation 2016/52 are based on the following assumption.
A person consuming a diet where 10% of their food was contaminated at the maximum level will, their additional radiation exposure would be limited to 1 millisievert (mSv) per year—a level considered safe by international standards.
For context, Public Health England has calculated that the average person in the UK is exposed to about 2.7 mSv of radiation per year, mostly from natural sources.
Notes on the units used to describe radioactivity
The limits are set in Bq/kg (becquerel per kilogram). A becquerel is an amount of radiation emitted equal to the number of disintegrations per second the radionuclide undergoes.
Roughly speaking, the more becquerels, the more the harmful radiation, but this may be misleading, because there are different types of radiation (alpha, beta, gamma, and neutron radiation), each with its own adverse health effect. In addition, the health effect depends on parameters such as the food, its consumption, and the age of the consumer.
1 millisievert (1 mSv) corresponds to the permitted additional annual dose limit for a member of the public. The sievert is a derived unit that describes a dose of radiation in terms of the biological effect that it has on the human body. The definition of the sievert depends on the relationship between the type of radiation and its impact on the various organs and tissues of the human body. It is determined by the International Commission on Radiological Protection.