Kumar Sudhir, Gupta A B, Gupta Sunil
Civil Engineering Department, Malaviya Regional College, Jaipur-17.
Indian J Environ Health. 2002 Apr;44(2):168-72.
An attempt has been made to classify ground waters in various districts of Rajasthan based on distribution of nitrate in their drinking water samples. It is seen that nitrate in ground water is unevenly distributed in the state. Major parts of Churu, Alwar, Bharatpur, Jalore, Jaipur, Sikar, Tonk and Jhunjhunu, are inherited by nitrate rich ground waters while districts like Banswara, Bundi, Bikaner, Chittor, Kota and Jhalawar have low nitrates in their ground waters at many places. It is well documented internationally that water supplied containing high levels of nitrate have been responsible for cases of infantile methemoglobinemia which may ultimately lead to death. A very high infant mortality rate in Rajasthan might be a consequence of high nitrates in drinking water supply. Some recent studies have shown that nitrates in drinking water besides causing methemoglobinemia can result in various other clinical manifestations like recurrent stomatitis, recurrent respiratory tract infections (RRTI) etc. These findings have indicated that a rethinking has to be given to the existing standards for nitrates in drinking water. Based on potential nitrate toxicity studies in view of above health effects the whole region has been classified into five water quality zones, namely, safe, mild, moderately problematic, highly problematic and dangerous. For areas falling under fourth and fifth zones it is recommended that immediate measures be taken to overcome the adverse health effects.
已尝试根据拉贾斯坦邦不同地区饮用水样本中硝酸盐的分布情况对地下水进行分类。可以看出，该邦地下水中的硝酸盐分布不均。楚鲁、阿尔瓦尔、巴拉特普尔、贾洛尔、斋浦尔、锡卡尔、托克和朱尼胡努的大部分地区都有富含硝酸盐的地下水，而像班斯瓦拉、本迪、比卡内尔、奇特托、科塔和贾拉瓦尔等地区，许多地方的地下水中硝酸盐含量较低。国际上有充分的文献记载，供应含高浓度硝酸盐的水会导致婴儿高铁血红蛋白血症病例，最终可能导致死亡。拉贾斯坦邦极高的婴儿死亡率可能是饮用水中硝酸盐含量高的结果。最近的一些研究表明，饮用水中的硝酸盐除了会导致高铁血红蛋白血症外，还会引发各种其他临床表现，如复发性口腔炎、复发性呼吸道感染（RRTI）等。这些发现表明，必须重新审视现行的饮用水硝酸盐标准。鉴于上述健康影响，基于潜在的硝酸盐毒性研究，整个地区已被划分为五个水质区，即安全、轻度、中度问题、高度问题和危险区。对于属于第四和第五区的地区，建议立即采取措施以克服不利的健康影响。
