概括
北美奶粉中-90和-137的含量与降雨中的放射性相关. 恒定的-90与-137比率表明可预测的环境污染模式.
科学领域:
- 环境科学 环境科学
- 放射化学 放射化学是指辐射化学.
- 核污染是核污染的原因之一.
背景情况:
- 放射性同位素如-90 (Sr-90) 和-137 (Cs-137) 是环境污染物.
- 了解它们在食物来源中的分布对于公共卫生监测至关重要.
研究的目的:
- 分析北美各地奶粉中Sr-90和Cs-137的度.
- 调查这些放射性核素水平与降雨特异性活动之间的关系.
- 为了确定粉末牛奶样本中Sr-90/Cs-137比率的可变性.
主要方法:
- 分析了800多个奶粉样本.
- 在北美各地的60个站点进行采样.
- 数据收集期间:1957年至1960年.
主要成果:
- 粉末牛奶中Sr-90和Cs-137的度通常跟随着降雨特异性活动的变化.
- 在许多样本中,Sr-90/Cs-137的比率显示出44%的低标准偏差.
- 这表明放射性核酸沉积和吸收的一致模式.
结论:
- 奶粉中的Sr-90/Cs-137比率是环境放射性污染的可靠指标.
- 这些发现支持大气沉积通过雨水和食物链中的放射性核化物水平之间的相关性.
- 该研究强调了在食品供应中持续监测放射性同位素的重要性.
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