Post-Chernobyl monitoring and controls survey reports
The Food Standards Agency is responsible for ensuring food safety by preventing products with unacceptable levels of radioactivity from entering the food chain. Widespread monitoring in 1986 identified food safety concerns from meat from sheep grazing in the affected areas. The Agency manages restrictions on the movement of sheep in the affected areas to protect consumers.
The Agency's primary concern is to ensure food safety by maintaining these controls, but also remove controls where these are no longer necessary.
Of the 9,800 UK holdings, and more than 4 million sheep, originally placed under restriction following the accident, there are 334 farms that remain under some form of restriction in North Wales, and in Cumbria, only eight farms still remain under restriction. All Mark and Release controls were lifted in Northern Ireland in 2000 and in Scotland in 2010.
The Agency has reviewed the post-Chernobyl sheep controls to assess whether these protective measures are still required to maintain food safety. To inform this review, an assessment has been made of the levels of radiocaesium in sheep within the restricted areas during the summers of 2010 and 2011, and the potential consumer doses if control measures were to be lifted. The survey showed that the levels of radiocaesium rarely exceed the 1,000 Bq/kg limit during the summer months, when levels tend to be at their peak. An assessment of the radiation doses that more highly exposed consumers could receive from eating sheep meat from these farms, shows that the consumer risk is now very low. The assessment report can be accessed via the link below.
The Agency has launched a consultation to seek the views of a range of stakeholders on the removal of the existing post-Chernobyl sheep controls. Details of the consultation and how to respond can be accessed via the link below.
During the review consultation period, and until a final decision is made, the current restrictions on the movement of sheep will remain in place.
Background to the Chernobyl accident
In 1986, an accident at the Chernobyl nuclear power plant in the former USSR (now Ukraine) released large quantities of radioactivity into the atmosphere. Some of this radioactivity, predominantly radiocaesium-137, was deposited on certain upland areas of the UK, where sheep farming is the primary land-use.
Due to the particular chemical and physical properties of the peaty soil types present in these upland areas, the radiocaesium is still able to pass easily from soil to grass and so accumulates in sheep.
Food safety controls
A maximum limit of 1,000 becquerels per kilogram (Bq/kg) of radiocaesium is applied to sheep meat affected by the accident to protect consumers. This limit was introduced in the UK in 1986, based on advice from the European Commission's Article 31 group of experts.
Under powers provided in the Food and Environment Protection Act 1985 (FEPA), which can be found on the Office of Public Sector Information website via the link below, emergency orders have been used since 1986 to impose restrictions on the movement and sale of sheep exceeding the limit in certain parts of Cumbria, North Wales, Scotland and Northern Ireland. The emergency orders define geographical areas, often termed 'restricted areas', within which the controls must be followed. Under the FEPA orders, sheep with levels of contamination above the limit are not allowed to enter the food chain.
A management system known as the Mark and Release scheme operates in restricted areas. Under this scheme, a farmer wishing to move sheep out of a restricted area can have them monitored to determine the level of radiocaesium.
A live monitoring technique is used, where a radiation monitor is held against the sheep, giving a count rate (in counts per second), which is converted to a concentration (becquerels per kilogram or Bq/kg) using a derived conversion factor. To allow for inherent variability in live monitoring results, a pass mark is applied, which has been set so there is only a 1 in 40 chance of a sheep above the limit giving a monitor reading below.
Any sheep that exceed the monitoring pass mark are marked with a dye and are not released from restrictions. Those that pass are allowed to enter the food chain.
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