在本篇 代写网站-饮用水中HAAs的允许限量分析中发现,纵观世界,许多发达国家和其他发展中国家已经建立了THM存在的基本标准,但遗憾的是,在饮用水中并没有规定HAAs的允许限量(Righi et al., 2014)。最近,人们做了大量的工作来记录饮用水中不同种类的HAAs的存在和出现,它们分别在DBPs和THMs之后占了很大的比例。关于突然越来越感兴趣的原因对哈斯的影响和存在的饮用水来自这样一个事实:不同的毒理学研究证实长期接触哈斯从饮用水导致癌症实验室动物暴露在相同的实验条件下(Procházka et al ., 2015),接下来有关代写网站-饮用水中HAAs的允许限量分析如下:

Additionally, a recent epidemiological data published (Smith et al., 2016) have shown that the levels of HAAs in drinking water has enhanced the risks of cancer in human beings upon long term exposure. Thus, it is clear that the presence of HAAs in drinking water is directly associated with cancer risks and steps are needed in order to establish the permissible levels of HAAs in drinking water. The excessive presence of the same poses serious health threats not only for human beings but also all other forms of life existing in nature.

The levels of all 5 classes of HAAs though have been predefined to be 0.06mg/L in USA, yet the actual values of DBPs vary significantly as a result of seasonal differences with the addition of geographical distribution of various water bodies (Cardador & Gallego, 2014). The reasons for such variations could be the quality of raw water, the treatment conditions and the operational procedures and parameters have a direct relationship with the process of chlorination in drinking water supply.

The various types of operational procedures which have a direct influence on HAA formation in the treatment regimen of water include the dose of chlorine use, the contact time of chlorine with organic matter dissolved in water, the temperature of the water being treated, the pH, levels of bromide and TOC levels. Researchers have highlighted the fact that the hydrophilic portion of the natural organic matter (NOM) along with amino acids have important precursors which form the HAAs and they have severe effect on the quality of water.

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