铜水管的卫生安全研究

目的：评价铜水管对水质的影响。方法：采集1家国外企业和2家国内企业生产的24根直径15mm、长0．5m的紫铜水管和20个黄铜管件进行24h浸泡实验并检测水质变化。选择北京市以市政管网为水源使用铜水管超过1a的2个用户和使用少于3个月的2个用户检测末梢水水质变化。结果：浸泡实验显示浸泡水中溶解性总固体、铜、铅、锌、镍浓度不同程度超标，pH值、余氯、总碱度、总硬度、硫酸盐、氯化物、硝酸盐、铬、镉、锡、砷浓度达标。使用铜水管的用户末梢水中总硬度、镉、镍浓度不同程度超标，其余指标均达标。结论：紫铜水管配合黄铜管件使用存在很多卫生学问题，尤其是黄铜管件，其浸泡水卫生学指标超标是铜水管水质超标的主要原因之一，但铜水管水质超标的原因不能完全归咎于黄铜管件。现场调查显示铜水管用户末梢水部分指标超标与使用不锈钢水龙头有关，故铜水管基本满足我国饮用水质卫生要求。

Study on Health Safety of Copper Water Tube

Objective To assess the effects of copper water tube and its joints on the sanitary quality of drinking water. Methods 24 red coppper water tubes at a length of 0.5 m with diameter of 15 mm and 20 brass joints were sampled from one foreign enterprise and two domestic enterprises for 24h-immersion test, the sanitary quality of water was determined during the process of immersion test. In another in situ experiment, the tap water sampled were collected from 4 families equipped with copper water tube in Beijing, in 2 of which the copper water tube and joints had been in use for more than one year, other 2 for less than 3 months. For all of these 4 families, the water supply pipes connected with the municipal water supply system. Results The immersion test showed that the levels of some sanitary indexes of the immersion water including total dissovled solids (TDS), copper, lead, zinc, nickel exceeded the related standards in different degree, other indexes including pH value, residual chlorine, total alkalinity, total hardness. sulphate, chloride, nitrate, chromium, cadmium, tin and arsenic accorded with the related standards. The levels of total hardness, cadmium and nickel in tap water samples collected from copper water tube-equipped families exceeded the related standards, Other indexes were qualified. Conclusion A lot of sanitary problems were found in the application of red copper water tubes combined with brass joints, especially for brass joints which played an important role but ont uniquely in deteriorating sanitary quality of drinking water distributed by copper water tubes and its joint.The in situ investigation indicated that some unqualified indexes of tap water samples were mainly associated with the stainless steel taps jointed with copper tube, so copper water tubes basically met the requirement of sanitary standard of drinking water in China.