Читать книгу Industrial and Medical Nuclear Accidents - Jean-Claude Amiard - Страница 72

Contamination of the food chain by ruthenium 106 is known, with the contamination of laverbread (made from the seaweed Porphyra sp.) around Windscale and beyond in the Irish Sea causing a partial exposure of the population in 1959 of 7 mSv [AMI 13a]. The risk in the case of this Russian accident (Mayak) would be the consumption of mushrooms. The maximum acceptable standard (MAS) for this radionuclide in mushrooms is 1,250 Bq.kg⁻¹. The transfer factor from soil to fungal mycelium is about 10² m².kg⁻¹. Therefore, to exceed the MAS, it is necessary that the soil be contaminated to more than 2,000,000,000 Bq.m⁻², which in this accident represents about a 2 km radius. In addition, for a child (2–7 years old) to exceed the committed effective dose by ingestion of 1 mSv, they would have to eat 32 kg of mushrooms in 1 year [IRS 17c].