Comparison of drinking water mutagenicity with leaching of polycyclic aromatic hydrocarbons from water distribution pipes

The primary objectives of this study were to examine the changes in concentration of six polycyclic aromatic hydrocarbons (PAH) and the possibility of changes in mutagenic potential of treated waters as a result of their passage through commonly used distribution pipes. With the exception of the finished water taken at one treatment plant in which the total concentration of the six PAH was 138.5 parts per trillion (ppt), the total initial concentration in all other treated water ranged from 0 to 13.4 ppt. The corresponding total PAH concentration in water after passage through the distribution pipes varied from 0 to 61.6 ppt. This demonstrated that PAH concentration in water can increase as a result of their passage through coated distribution pipes. Mutagenic activity was also detected in many of the treated water samples, however, the levels of this activity did not correlate with either the transit of water through the distribution system or the levels of PAH in the water. There was some evidence to indicate that the water treatment process itself may have contributed to the mutagenicity observed in the finished water.     

Emerging contaminants migration from pipes used in drinking water distribution systems: a review of the scientific literature

Environmental Science and Pollution Research - Migration of emerging contaminants (ECs) from pipes into water is a global concern due to potential human health effects. Nevertheless, a review of...     

不同管材水管与静态自来水水质间的相互影响

对比了铝塑复合管(PAP)、铜管、不锈钢管和镀锌铁管对静态自来水的总有机碳(TOC)、溶解氧(DO)、浊度、细菌总数和大肠菌群等水质指标的影响。实验结果表明,铜管对自来水水质指标影响最小,且具有良好的卫生性能。同时,通过场发射扫描电子显微镜(FESEM)的观察,对比分析了铜管和铝塑复合管在浸泡实验前后其内表面形态特征的变化,结果显示自来水中浸泡10个月以后,铜管内表面密集地分布着块状的孔雀石晶体,而铝塑复合管内表面已严重变形,产生很多褶皱。     

不同管材水管与静态自来水水质间的相互影响

对比了铝塑复合管（PAP）、铜管、不锈钢管和镀锌铁管对静态自来水的总有机碳（TOC）、溶解氧（DO）、浊度、细菌总数和大肠菌群等水质指标的影响。实验结果表明，铜管对自来水水质指标影响最小，且具有良好的卫生性能。同时，通过场发射扫描电子显微镜（FESEM）的观察，对比分析了铜管和铝塑复合管在浸泡实验前后其内表面形态特征的变化，结果显示自来水中浸泡10个月以后，铜管内表面密集地分布着块状的孔雀石晶体，而铝塑复合管内表面已严重变形，产生很多褶皱。     

Pilot study on the contamination of drinking water by organotin compounds from PVC materials

Raw and treated water samples and tap water samples from four to six houses located on distribution lines where PVC pipe/tubing had been recently installed were collected in five Canadian municipalities for the analysis of organotin compounds. After derivatisation with sodium tetraethylborate the ethylated organotin compounds were extracted with hexane and analysed by gas chromatography-microwave induced plasma atomic emission spectrometry using a wavelength (326.234 nm) specific for tin. Organotin compounds, mainly methyltin and dimethyltin at concentrations ranging respectively from 0.5 to 257 ng Sn/L and from 0.5 to 6.5 ng Sn/L, were detected in samples from ten of the twenty-two houses. No organotin compounds were detected in raw water or treated water leaving the treatment plant, indicating that the organotin compounds were leaching into the water from some component of the distribution system.     

Metal distribution in sediments of a drinking water reservoir: influence of reservoir morphometry and hydrodynamics

Environmental Science and Pollution Research - Metal(loid)s in the reservoir sediment tend to be released into the water column when encountering disturbances and thus pose threats to the aquatic...     

A study on organotin levels in Canadian drinking water distributed through PVC pipes

A study on organotin compounds in Canadian drinking water was carried out in winter-spring 1996 (28 sites) and autumn 1996 (21 sites). Approximately 29% and 40% of distribution waters supplied through PVC pipes installed recently (typically less than 6 months) contained organotin compounds in the winter-spring and autumn surveys respectively. Monomethyl-, dimethyl-, monobutyl- and dibutyltin levels ranged up to 291 ng Sn/L, 49.1 ng Sn/L, 28.5 ng Sn/L and 52.3 ng Sn/L, respectively. An additional study in summer 1996, of locations where the highest organotin levels were detected in the winter-spring survey, indicated that organotin levels had decreased in most distribution water samples. Samples of PVC pipe/tubing contained organotin compounds consistent with the organotin patterns found in the distribution water samples.     

老旧无内衬铸铁管中氯对水质的影响

给水管网铁释放对于饮用水水质具有重要影响。通过浸泡实验和烧杯实验探究实际老旧无内衬铸铁管中氯对铁腐蚀的影响。一方面,通过实际管段浸泡实验,对比了不同初始氯浓度下管道中水质变化,发现在高初始氯下浊度和三磷酸腺苷增大,这表明在铁释放严重的无衬里铸铁管道中,消毒剂的增加可能引发水质微生物风险;另一方面,通过烧杯实验进一步确认了氯对管网颗粒物结构的影响,发现氯能够通过降低颗粒物表面电荷导致静电排斥降低,从而加剧了颗粒物的团聚,导致粒径变大、浊度升高,且颗粒物对消毒副产物三卤甲烷具有一定的富集累积作用,引发水质化学风险。本研究结果可为了解给水管网中氯引发的黄水风险提供参考。     

Chlorophenols in lake bottom sediments: A retrospective study of drinking water contamination

Lake and brook bottom sediments were analyzed for chlorophenols to provide historical data of exposure assessment, after the water intake plant of a Finnish village had been found to be contaminated in 1987, and subsequently elevated non-Hodgkin lymphoma risk was detected. Highly elevated 2,3,4,6-tetrachlorophenol and pentachlorophenol levels were found in all four lake sediment cores investigated. The distribution was uneven with much higher concentrations in the estuary, in contrast to PCB compounds which were more evenly distributed within the basin. The inlet origin of the chlorophenols in the sediments was further supported by the regional distribution pattern of these compounds in the sediment and water along transects of the inlet and its tributaries. The composition of chlorophenol congeners in the sediments was similar to that in a commercial fungicide used by a local sawmill, but different from other sediment analyses reported in Finland, also implying a local source. Dating of three cores by Pb-210 and soot ball chronology indicated that the contamination of the watercourse started in the early 1970s at the latest but possibly earlier. This would provide the latency time required for tumour appearance in the 1970s and 1980s.     

水源切换条件下模拟管网铁离子释放控制简

用北京市某供水区域铸铁管段搭建2套模拟管网装置,对水源切换条件下管网铁离子释放的控制进行了研究。实验过程中利用地下水为水源,通过调节进入管网的水中氯浓度为1.0~1.1 mg/L,溶解氧浓度为7~8 mg/L,经过40 d运行后,管垢成分主要为α-FeOOH和Fe₃O₄。切换地表水源后,新的管垢组成更有助于铁氧化物中铁的氧化还原重新达到平衡,从而可以有效减少水源切换条件下铁离子的释放,管网出水浊度也得到很好的控制,保持了管网水质稳定性。     

水源切换条件下模拟管网铁离子释放控制

用北京市某供水区域铸铁管段搭建2套模拟管网装置,对水源切换条件下管网铁离子释放的控制进行了研究。实验过程中利用地下水为水源,通过调节进入管网的水中氯浓度为1.0~1.1 mg/L,溶解氧浓度为7~8 mg/L,经过40 d运行后,管垢成分主要为α-FeOOH和Fe3O4。切换地表水源后,新的管垢组成更有助于铁氧化物中铁的氧化还原重新达到平衡,从而可以有效减少水源切换条件下铁离子的释放,管网出水浊度也得到很好的控制,保持了管网水质稳定性。     

饮用水管网生物膜细菌群落特征及其对腐蚀的影响

通过454高通量测序对北方A和B两实际饮用水管网系统中生物膜细菌群落特征进行表征,并研究了其对管网腐蚀产物组成的影响。结果表明,A管网生物膜细菌群落丰度和多样性高于B管网生物膜。在门水平上,两管网生物膜细菌群落主要为变形菌门Proteobacteria,但B管网生物膜中的相对丰度（67.10%）高于A（46.50%）。在纲水平上,A管网生物膜主要为β-变形菌纲Betaproteobacteria,B管网生物膜中主要为β-变形菌纲Betaproteobacteria和δ-变形菌纲Deltaproteobacteria。在属水平上,A管网生物膜中腐蚀相关菌群主要为硝酸盐还原菌和铁还原菌,其腐蚀产物主要为α-FeOOH和Fe3O4,而B管网生物膜中硫酸盐还原菌特别是脱硫弧菌属Desulfovibrio含量较高,其可能与管垢中绿锈含量高有关。     

多水源供水管网中消毒副产物风险分析

通过调研北方某大型城市多水源供水格局下管网水中三卤甲烷(THMs)和卤乙酸(HAAs)这2类消毒副产物(DBPs)的质量浓度水平,对管网中各类DBPs的超标风险、风险点的时空分布及影响因素进行了分析,从确定管网指示性DBPs、检测频率及管网采样点布设3个方面提出了关于管网DBPs风险分析方法的建议.研究结果表明,该市D...     

管道特征对给水管网中锰释放的影响

针对南方某市历年来与锰相关的多次黄水问题,在当地黄水多发区域挖取10年管龄的旧PE管和20年管龄的镀锌钢管,搭建中试装置,开展了管网中锰释放行为的中试研究,并以新PE管做对比,探讨了微生物对管网内锰的氧化沉积的影响。实验结果表明,在进水锰浓度很低时,镀锌钢管与旧PE管的管壁沉积物中均会出现锰的释放。镀锌钢管中释放的锰主要为溶解性锰,释放量大;而旧PE管中释放的锰主要为不溶态的锰,且释放量小。同时,镀锌钢管管道浸泡结果表明,随着余氯浓度的提高,镀锌钢管中溶解锰的释放会显著降低,但即使余氯浓度高达15 mg·L-1仍会有25.3 μg·L-1的溶解锰的释放。新旧PE管的对比实验表明,当提高进水Mn（Ⅱ）浓度时,旧PE管中Mn（Ⅱ）在6.67 h内的氧化量低于新PE管,这可能是旧PE管生物膜中的锰还原菌含量较多导致的。     

臭氧对饮用水管网中溶解性有机物的影响

利用生物膜环状反应器模拟配水管网系统,将水厂砂滤池出水经过臭氧氧化后投加氯然后进入该模拟管网,另外把水厂砂滤池出水加氯后通入另一模拟管网作为对照实验。通过对两管网出水余氯、总铁、浊度、溶解性有机物(DOC)、以及消毒副产物三卤甲烷(THMs)、卤乙酸(HAAs)生成情况的测定,研究了饮用水臭氧处理对管网出水水质的影响。单因素方差分析结果表明,两管网出水的余氯、总铁、浊度以及THMs、HAAs含量相差不大,但DOC在臭氧氯管网中消耗较多。同时通过高效凝胶色谱(HPSEC), 红外光谱(FTIR)和三维荧光光谱(EEM)表征了不同管网进出水DOC变化,结果表明,臭氧氧化后的管网出水中溶解性有机物荧光光谱中三区富里酸和五区腐植酸荧光峰值(ФⅢ+Ⅴ,n)减小较多,管网出水消毒副产物稍有增加。     

某水源水库嗅味来源及潜在产嗅藻分布特征解析

华东地区某水源水库近年来出现季节性嗅味问题。为解析嗅味产生来源及其成因,于2018年4月至2019年12月对该水库上游以及库内水体进行长期监测。监测结果表明,2-甲基异莰醇(2-MIB)是主要的土霉味致嗅物质,伪鱼腥藻是该水库潜在产嗅藻种,且其主要为外源输入。相关性分析结果表明,伪鱼腥藻的生长与水温及水下光照(透明度、浊度)等有关。为进一步解析水下光照因素驱动下伪鱼腥藻在水库水体中的分布特征,在水库高嗅期间开展了72 h连续监测,重点分析了伪鱼腥藻昼夜与垂向分布特征。结果表明,在08:00,伪鱼腥藻往表层迁移,在10:00—14:00,表层密度达到最高值,白天在水体中呈现明显的垂向迁移特征,而夜晚在水体中各层的分布无明显变化,这进一步说明水下光照对伪鱼腥藻生长的重要性。以上结果进一步提升了对实际水体中伪鱼腥藻分布规律的认识,可为水源地中伪鱼腥藻导致的嗅味问题提供借鉴。     

饮用水除砷技术研究进展

饮用水中的砷对人体健康危害很大。介绍了从饮用水中去除砷的各种方法,总结了目前除砷技术存在的不足,指出混凝微滤工艺具有除砷效率高、能耗低、操作简单等优点,应成为今后饮用水除砷技术的发展方向。     

ACF电吸附去除饮用水中的硝酸盐

电吸附除盐技术是一种新型的饮用水处理技术,具有能耗低、无二次污染和电极可重复利用等优点。采用活性炭纤维(ACF)作为电极材料对其电吸附去除水中的硝酸盐进行了研究,考察了电压、pH、流速、初始浓度等因素对电吸附效率的影响以及超声处理对电极脱附和再次利用的影响。结果表明,电吸附作用对硝酸盐的去除有较高的效率,最佳的工艺条件为:电压1.0 V,pH为5.0~6.0,进水流速10 mL·min-1,初始NO3--N浓度为25~30 mg·L-1,在该条件下硝酸盐去除效率为68.3%~72.62%。超声处理对电极的脱附作用和再生效率有较大的改善和提高,超声处理过的电极比未处理的电极对硝酸盐的去除率可提高16.10%~18.98%。     

给水管网疏松沉积物的结构特征及其风险识别

自来水变色问题通常被视为感官问题,而导致自来水变色的管网疏松沉积物的结构特征及其潜在危害尚不明确。采集了我国北方某城市频繁发生自来水“黄水”的7个小区管网中的疏松沉积物,并进行了分析。结果表明：所有疏松沉积物样品中含量最高的金属元素都是铁元素、主要晶体成分是铁氧化物,样品颗粒微观形貌大多具有锋利的针刺状结构;样品zeta电位范围为−15~20 mV、平均粒径范围为500~4 000 nm、粗糙度范围为0.25~7.81 nm。体外细胞毒性实验结果显示,沉积物可产生一定的细胞毒性(样品浓度100 mg·L⁻¹时人体健康肝脏细胞存活率为86.61%~99.71%)。通过主成分分析发现,疏松沉积物毒性与粗糙度的相关性比与粒度的高,表明形貌对样品毒性的影响比粒径更大;γ-FeOOH是与疏松沉积物毒性相关性最显著的晶体组分,其对毒性的贡献可能是通过增加颗粒表面锋利程度造成的,余氯不足时可能会因铁释放加剧和γ-FeOOH含量增大造成更高的毒性风险。本研究结果可为全面认识给水管网疏松沉积物的风险提供参考。