Protective measures for primary food production in a nuclear or radiological emergency, Protection of plant-based foodstuffs and feeds

Publish date: December 1/2022

Guide 7435/

Preparing for nuclear or radiological emergencies is important to protect a safe and secure food chain. In primary production, relatively small measures are efficient in preventing the contamination of food or raw ingredients in a nuclear or radiological emergency.

Even if external radiation dose rates do not rise much above the normal prevailing radiation level during a nuclear or radiological emergency, foodstuffs may eventually contain enough radioactive material to exceed accepted levels, which would prevent them from being placed on the market. In the event of a nuclear or radiological emergency, the protection of primary food and animal feed production should be initiated as soon as possible. Protective measures must be in place before radioactive materials arrive in the region. Radioactive iodine, for example, is rapidly transferred into milk if cattle are fed contaminated feed. The more comprehensive and efficient the protective measures, the smaller the harm caused by a nuclear or radiation emergency. Furthermore, after the passing of a radioactive plume, various measures aimed at the cleanliness of primary produce may be required in the contaminated area.

These guidelines provide a concise description of the measures that can be taken in primary foodstuff and feed production to prepare for nuclear or radiological emergencies. Instructions on the protection measures (e.g., cleaning) to be taken before the arrival and after the passing of a radioactive plume are given separately. Different actions suitable for each type of farm should be considered in advance – not when a nuclear or radiation incident has already occurred.

It is essential to ensure that each farm has the necessary protective equipment, including:

  • respirators and protective clothing for workers;
  • plastic sheets, tarpaulins, protective covers;
  • filters suitable for the ventilation system/ filter cloth, fibre glass, rock wool
  • sealing tape
  • cloths and rags suitable for cleaning

More information on the protective actions in primary food production is available in STUK publication Protective actions in a nuclear or radiological emergency.

The protective actions to be taken before the arrival of a radioactive plume help prevent contamination. Contamination can be likened to very fine invisible dust from which people, animals, plants, animal feed and foodstuffs must be protected. In primary food production, protective measures are aimed at workers, production animals, feeds, animal drinking water, production facilities and plantations. After a radioactive plume passes, essential actions include those preventing the contamination of primary produce by radioactive fallout on the soil and other surfaces (e.g., cleaning production facilities and ensuring the safety of production animal feed products).

Protective actions and other measures should be taken only at the instruction of authorities and based on their recommendations and only when they can be taken without endangering animal welfare. Naturally, preparedness for protection measures must be initiated independently as soon as information of a potential nuclear or radiation emergency threatening the region is received. Authorities monitor nuclear or radiation emergencies and issue guidelines and recommendations on what actions must be taken, when, and in which areas. Food safety authorities will issue more specific instructions on protective actions as necessary. Information about the division of tasks and responsibilities between different agencies is available in the Ministry of the Interior publication Säteilytilanneohje (in Finnish; Guidelines for nuclear or radiological emergencies .

Protective actions taken before the arrival of radioactive materials in the region

  • Where possible, the ventilation of greenhouses and other production and storage facilities is shut down or the supply air filtered (effective supply air filter, filter cloth, glass wool, rock wool); hatches are sealed if necessary and possible
  • silos are shut down and hatches are sealed if necessary
  • grain is harvested and protected; cultivated areas (e.g., vegetable gardens, berry shrubs) are covered with plastic, tarpaulins etc., if possible, taking into account the availability of time and the extent of cultivation

Protective actions carried out after the passing of a radioactive plume

  • rainwater collected during a nuclear or radiological emergency must not be used for irrigation
  • crops that cannot be covered in time for the arrival of radioactive materials in the region are cut or threshed before the first rainfall (plant waste is disposed of) to protect the cleanliness of fields and cultivations
  • snow cover on crops is removed (in the winter)
  • fields are ploughed and the top soil is removed if necessary
  • potassium fertilisers reduce the amount of caesium absorbed by plants and liming reduces the absorption of strontium
  • appropriate species for cultivation are selected (particularly in the growth season  following a nuclear or radiological emergency); optimised fertilisation
  • contaminated manure is not used with plants and pastures used in food and feed production

Further information: