Radioactivity in foods can occur by two routes:

1. contamination of foods with radioactive substances
2. penetration of energy into the nuclei of the atoms that make up the food.

The irradiation process involves passing food through an irradiation field. While in the irradiation field, the food itself never contacts a radioactive substance. In addition, the ionizing radiation used by irradiators is not of sufficient energy to disintegrate the nucleus of even one atom of a food molecule.

The U. S. Department of Agriculture has documented [local] the risk analysis issues associated with irradiation of meat.