Contaminant Minimization for Safer Drinking Water

拟议研究计划的最终目标是改善向所有人提供安全饮用水，特别是在最大限度地减少对人类健康构成潜在威胁的化学污染物方面。总体而言，参与这项研究的HQP将发现并报告一些因素，这些因素可以改善水中微量污染物的去除和/或在使用传统和/或创新处理工艺时将水的消毒或氧化处理产生的副产品降至最低。即使在微量水平上，饮用水中的几种污染物也已知或怀疑会对人类健康造成不利影响。例如，亚硝胺在ng/L(万亿分之一)的浓度下可以产生致癌作用，可以存在于原水中，也可以作为消毒副产品形成。某些药物也可以进入我们的饮用水处理厂进水口，通常是上游废水排放的结果，可能是饮用水处理厂进水的很大一部分，特别是在高度城市化的地区。它们不容易被传统的处理程序去除，虽然它们的直接影响被认为是最小的，但其中一些可以在处理过程中转化为上述亚硝胺。此外，随着分析方法和毒理学测试方案的发展，亚硝胺和药物等“新出现的污染物”清单继续增加。一些痕量污染物甚至正在“重新出现”。例如，20多年前作为氯化副产品被发现的名为“诱变剂X”的化合物，目前正在重新检查其对健康的潜在影响和可治疗性。特别令人感兴趣的是最近发现的微型塑料颗粒(微米或纳米尺寸的塑料)，已被证明包含在器官和组织中，要么直接对健康造成影响，要么是将上述一些污染物传播到可能产生影响的组织中的媒介。吸附在其上的物质在处理过程中也可能与消毒剂发生反应，并形成上述副产品。通过提议的精心规划和执行的研究，希望可以发现和采用减少这些和其他化学污染物在我们饮用水中的发生和影响的方法。

The ultimate objective of the proposed research program is to improve the provision of safe drinking water to all, particularly in regards to minimizing chemical contaminants that are of potential human health concern.           Generally, the HQP involved in this research will discover and report on factors which improve the removal of trace contaminants from water and/or minimize byproducts formed from the disinfection or oxidative treatment of water when using conventional and/or innovative treatment processes. Even at trace levels, several contaminants in drinking water have known or suspected adverse human health effects. Nitrosamines, for example, can exert carcinogenic effects at ng/L (parts-per-trillion) concentrations and can be present either in the raw water or are formed as byproducts of disinfection. Certain pharmaceuticals can also find their way into our drinking water treatment plant intakes, usually as a result of upstream wastewater discharges and can be a significant fraction of a drinking water treatment plant's influent water, especially in heavily urbanized areas. They are not readily removed by conventional treatment processes, and while their direct effects are thought to be minimal some of them can be transformed during treatment into the nitrosamines mentioned above.           In addition, the list of `emerging contaminants' like nitrosamines and pharmaceuticals continues to grow as analytical methods and toxicological testing protocols evolve. Some trace contaminants are even `re-emerging'. For example, the compound known as `mutagen X', discovered as a chlorination byproduct more than 20 years ago, is currently being re-examined for its potential health impacts and treatability.  Of particular interest has been the recent discovery of microscopic plastic particles (micron-sized or nanometer-sized plastics) that have been shown to be incorporated into organs and tissues and either cause health effects directly or be vectors for the transmission of some of the abovenamed contaminants into tissues where they may have effects. Materials adsorbed to them may also react with disinfectants during treatment and form byproducts such as those named above.           Through the carefully planned and executed research that is proposed, it is hoped that means to reduce the occurrence and impact of these and other chemical contaminants in our drinking water may be discovered and employed.