中国人发砷背景值及其区域分布特征

CHINESE HAIR As CONTENT BACKGROUND AND ITS REGIONAL DISTRIBUTION

本文作者在全国不同自然地理类型区选择１００余县近２００个采样点，采样点在远离城镇的非污染地区，采集当地居民发样１３１３份，用氢化物原子荧光法测定砷含量。测定数据进行计算机统计，结果表明，中国人发中砷含量在０．００４－９．９９９μｇ／ｇ之间，中位值为０．５６μｇ／ｇ，算术平均值为０．９２７±１．２１３μｇ／ｇ，几何平均值为０．５７１μｇ／ｇ。性别和年龄差别不明显。皮尔逊（Ｐｅｌｓｏｎ）ｘ２法和Ｗ检验法检验结果表明，在同一自然地理区，人发砷含量呈对数正态分布。中国人发砷的地理分布呈南方高，北方低，自北而南逐渐递增的规律。人发砷的几何均值在北方中温带地区为０．２－０．４μｇ／ｇ之间，到暖温带升高到０．４－０．６μｇ／ｇ，至北亚热带则达到０．７６７μｇ／ｇ，而到中亚热带以南则高达１μｇ／ｇ以上。在同一自然地理带内，东西间差异不明显，青藏地区亦属发砷低含量区（几何均值０．２６７μｇ／ｇ）。并依此对我国划分慢性砷中毒区的人发指标进行了讨论。

hair samples from about 200 sample sites are collected. These sites cover 103 counties and different types of natural conditions and are far from cities(or towns) or polluted areas.The hair As are analyzied by hydro-atomic fluorescence spetrophotometry and the data are caculated by computer.The results show Chinese hair As contents are between 0.004 and 9.999μg/g. The median is 0.56μg/g. The arithmetic mean is 0.927±1.213μg/g and the geometric mean is 0.571μg/g.There is no significent difference between sexes and ages. The results of Pelson x2 and Shapio-Wilk W tests show that the As content in the same physical geographical area has a logarithm normal dis tribution.Hair As contents in the South are significently higher than that in the North.The geometric means are 0. 2-0. 4μg/g in medium-temperate zone and 0.4-0.6μg/g in warm-temperate zone. In north-subtropical zone the hair As geometric mean is 0. 767μg/g and in medium-subtropical zone, south-subtropical and tropical zones, it is higher than 1.00μg/g.There is no difference in the same physical geographical zone.Hair AS content in the Qinghai-Tibet Pleatu area is also low(the geometric mean is 0.267μg/g).At last, the standard level of hair As content for chronic arsenism areas in China is also discussed.