壤塘县大骨节病病区环境中硒的分布特征

Selenium in Environment and its Relationship with Kaschin-Beck Disease in Rangtang County, Sichuan Province

大骨节病是一种地方性骨关节病,主要分布于环境低硒地区。目前,我国大部分地区大骨节病病情已经得到控制,病情相对活跃而严重的区域主要集中于青藏高原地区。四川省壤塘县地处青藏高原东南缘,大骨节病遍布全县各村且最低患病率不低于13.28%。本文选择不同病区采集了耕作土壤（0～20cm）、青稞、糌粑和饮用水等样品,并分析了样品含硒量与大骨节病病情的关系。结果表明：壤塘县大骨节病病区环境含硒水平很低,特别是病情比较严重的村子其环境含硒水平更低。耕作土壤和青稞籽粒含硒水平依次为中病区〉重病区〉极重病区。受制作过程中添加物的影响糌粑含硒水平为中病区〉重病区≈极重病区。虽然不同饮水类型硒的水平存在差异,但是,极重病区饮用水中含硒量也低于中病区和重病区。大骨节病与当地环境因素特别是主要粮食和食物含硒量的关系非常密切。在低硒环境条件下,由于饮水仅对人体硒的摄入起辅助性的作用,因此,调节和改善环境低硒地带居民的膳食结构,增加外源性高硒食物的输入,减少人体对低硒环境因素的依赖性,将会对大骨节病的防治具有重要的意义。

Previous studies have shown that KaschinlBeck Disease （KBD, a kind of endemic osteoarthropathic disease） is mainly distributed in the areas with low selenium in environment. At present, it has been controlled in most areas of China, but it is still relatively serious in Qinghai- Tibet Plateau region. Rangtang County of Sichuan Province is located in the southeastern part of Qinghai-Tibet Plateau. The KBD prevalence rate in every village in the county is higher than 13.28%. In this paper, some villages are selected by KBD prevalence rate. Samples of cultivated topsoil （0-20cm）, highland barley （Qingke）, tsamba and drinking water were collected. The relationship between selenium contents in the samples and KBD prevalence rate were analyzed. The results show that the selenium concentrations in all KBD villages are very low, especially in higher prevalence rate villages. The sequences of selenium contents in cultivated topsoil and highland barley grains are MKBD （middle prevalence rate villages） 〉HKBD （high prevalence rate villages）〉 VHKBD （very high prevalence rate villages） and those in tsamba （a kind of food made of highland barley and other adding materials） are MKBD 〉HKBD ≈VHKBD. Selenium concentrations in drinking water in VHKBD villages are also higher than those in MKBD and HKBD villages though the selenium levels between drinking water types are different. There are close relationships between KBD prevalence rate and selenium concentrations in the local environment, especially in foodstuff. Because the selenium in drinking water plays a less role in daily selenium intake of resident populations under the low selenium condition, it is important to import high selenium content grains or add selenium in food for KBD controlling and prevention in the area.