Yu K N
Department of Applied Science, City Polytechnic of Hong Kong, Kowloon Tong, Kowloon.
Health Phys. 1993 Sep;65(3):318-21. doi: 10.1097/00004032-199309000-00012.
This paper describes a method for monitoring 90Sr contamination in terms of 131I contamination in food imported from a country with a recent nuclear power plant accident. For imported food, the guideline levels set by the Codex Alimentarius Commission will be applied, which requires that the contamination in food by beta emitters (typically strontium) be monitored. However, the measurement of strontium contamination cannot be made within a reasonably short time as it requires rather time-consuming chemical extraction and sample preparation procedures in advance. We propose here to use the contamination level of 131I in these foodstuffs as indicators of 90Sr contamination levels. Possible accident scenarios are employed to estimate the abundance ratio of 131I and 90Sr deposited on soil and intercepted by plants. Using a dynamic food chain model, we can calculate their relative activities in the food products which, when combined with the 131I levels present, give the theoretical 90Sr levels present.
本文描述了一种根据从近期发生核电站事故国家进口食品中的¹³¹I污染情况来监测⁹⁰Sr污染的方法。对于进口食品，将采用食品法典委员会设定的指导水平，该水平要求监测食品中β发射体（通常是锶）的污染情况。然而，由于锶污染的测量需要事先进行相当耗时的化学提取和样品制备程序，所以无法在合理的短时间内完成。我们在此提议，将这些食品中¹³¹I的污染水平用作⁹⁰Sr污染水平的指标。采用可能的事故情景来估计沉积在土壤上并被植物截留的¹³¹I和⁹⁰Sr的丰度比。使用动态食物链模型，我们可以计算它们在食品中的相对活度，当与现有的¹³¹I水平相结合时，就能得出理论上存在的⁹⁰Sr水平。
