Nuclear accidents and radioactive contamination of foods

Overview

Radioactive isotopes of elements (radionuclides) are naturally present in the environment, and that includes our bodies and our food and water. We are exposed to radiation (also known as background radiation) from these radionuclides on a daily basis. Radiation comes from space (i.e., cosmic rays) as well as from naturally-occurring radioactive materials (radionuclides) found in the soil, water and air. Radioactivity can be detected in food and water and the concentration of naturally-occurring radionuclides varies depending on several factors such as local geology, climate and agricultural practices.

People can also be exposed to radiation from man-made activities, including medical diagnostic intervention. Radioactivity can contaminate food after it has been discharged into the environment from industries that concentrate natural radionuclides and from civil or military nuclear operations. Whether, man-made or natural in origin, radioactive material passes through the food chain in the same way as non-radioactive material. The degree of harm to human health depends on the type of radionuclides and the length of time people are exposed to it. The amount of radiation people are exposed to varies from place to place and among individuals.

In the event of releases of radioactivity following an emergency at a nuclear power plant, land, rivers, sea and structures in the vicinity of the power plant can become contaminated with a mixture of radionuclides generated inside the reactor, also known as “nuclear fission products”. Individuals can therefore become exposed to radiation from these fission products.