The following are facts, please draw your own conclusion.
K-40 Naturally occurring half-life = 1.2 billion years decay (89.28%) by beta decay; 1.31 MeV beta particle decay (10.72%) by electron capture with a 1.50 MeV gamma emission;
Cs-137 Man-made half-life = 30 years decay (94.6%) by beta decay; .51 MeV beta particle with a delayed .66 MeV gamma emission decay (5.4%) by beta decay; 1.17 MeV beta particle
Typical soil is naturally radioactive with an average activity of 400-500 Bq/Kg, but the range can vary greatly; the main radionuclide is K-40. Bananas can have an activity 80-150 Bq/Kg; the main radionuclide is K-40. Cs and K both act similarly biologically.
From this data, which radionuclide sounds more harmful? A naturally occurring radionuclide which is all around us, with a much longer half life and more energetic emissions? Or a man-made radionuclide which has contaminated soil, but is less energetic and has a shorter half-life? Both of these radionuclides are beta emitters. Cells do not care where the radiation came from; whether man-made or natural. Both have similar chances of causing cancer.
Yes, there are areas where Cs-137 concentrations are much higher than background radiation and therefore should have limits in food; but what should these limits be? Zero tolerance could be an answer, but is that realistic? Is it going to significantly reduce health effects? Remember that we are around much Potassium-40 every day, much higher than these strict government guidelines. We live on the soil and eat food where it occurs naturally at levels much higher than 100 Bq/Kg. Should we have a zero-tolerance mind towards naturally occurring radiation as well? You can't say man-made is bad and natural is good, your cells and DNA do not care.
Think about all this.
2 ( +2 / -0 )