白云鄂博稀土铁共生矿矿工肺内钍活度调查与评价的最新结果

The Latest Investigation and Assessment on Thorium Lung Burden of the Thorium-containing Dust Exposed Miners of the Bayan Obo Rare-earth Iron Mine

目的弄清白云鄂博稀土铁矿在1983-2001年间长期吸入含钍稀土粉尘矿工肺内钍沉积量平均值、最高值及达到一个调查水平人数,并对其作出卫生评价。方法用静电负高压呼出气中钍射气子体收集测量系统,获得每名被测矿工肺内钍的沉积量。结果751名矿工1 270人次的测定结果表明,其肺内钍沉积量平均值为1.576 Bq,最高值为11.11 Bq;肺内钍沉积量达到1个调查水平者占被检总人次的22.91%。结论调查结果表明该矿接尘矿工肺内钍沉积量的平均值与最高值和1983-1994年的调查结果一致。但由于有一定数量的矿工肺内钍沉积量达到了一个调查水平,该矿防护措施仍需加强。

Objective To investigate the average value, maximum value of the thorium lung burden of the thorium- containing dust exposed miners of the Bayan Obo Rare - earth Iron Mine as well as the number of those hating a thorium lung burden reached one investigation level （2.22 Bq）. Method By using the electrostatic negative high voltage exhaled thoron daughters collection and measurement system to obtain the thorium lung burden of each subject. Results The average value of the thorium lung burden from the 1 270 messurents of 751 dust exposed miners was 1.576 Bq （ ≈ 1.60 Bq）, the maximum value was 11.11 Bq. The thorium lung burden of 22.91% of the 1 270 measurements reached one investigation level （2.22 Bq）. Conclusion The average value and the maximum value of the thorium lung burden of the 1 270 measurements carried out during the period from 1983 - 2001 were as same as that of the values carried out during the period from 1983 - 1994. Owing to a certain percentage of the thorium lung burden measurements carded out in 1983 - 2001 reached one investigation level, the comprehensive protection measure in this mine should he enhanced.