Dear Nuclear Engineering International
I refer to the article on low dose radiation and it regulation in your July issue (page 18). I would like to point out a small typographical error on page 21, which affects the point being made quite significantly. The sentence reading “Consumption of food at the Codex Alimentarius limit level can lead to an individual dose of a few µSv/year” should read at the end “individual dose of a few mSv/year”.
Actually, the Codex guideline levels for various radionuclides are based on a reference level of dose of 5mSv, that being, for most radionuclides, the committed effective dose resulting from the consumption of radioactively contaminated food during the first year following a nuclear accident. Furthermore, the Codex divides radionuclides into three groups based on the dose per unit intake. It suggests that the 5mSv dose level be applied to each group in order to avoid being unneccesarily restrictive. So theoretically, an individual ingesting food contaminated at the levels specified can be exposed to as much as 15mSv. Many of the representative nuclides noted in the Codex have long half-lives. Thus the dose levels to the public cannot reduce significantly during the next few decades.
These factors make it interesting and relevant to compare the Codex dose levels with the 10µSv/year individual dose proposed by the IAEA and the EC for releasing material from the nuclear industry.