Determinants of drinking arsenic-contaminated tubewell water in Bangladesh

Bangladesh has already experienced the biggest catastrophe in the world due to arsenic contamination of drinking water. This study investigates the association of drinking arsenic-contaminated water (DACW) with both personal and household characteristics of 9116 household respondents using the household data of the Bangladesh Demographic and Health Survey (BDHS) 2004. Here DACW means that arsenic level in the drinking water is greater than the permissible limit (50 microg/l) of Bangladesh. The overall rate of DACW was 7.9%. It was found to be significantly associated with education, currently working, and division of Bangladesh, either by cross tabulation or multivariate logistic regression analyses or both. Similarly, household characteristics -- namely television, bicycle, materials of the wall and floor, total family members, number of sleeping rooms, and availability of foods -- were significantly associated in bivariate analyses. Many household characteristics -- namely electricity, television, wall and floor materials, and number of sleeping rooms -- revealed significant association in the logistic regression analysis when adjusted for age, education and division. This study indicates that respondents from Chittagong division and lower socio-economic groups (indicated by household characteristics) are at significantly higher risk of DACW. These findings should be taken into account during the planning of future intervention activities in Bangladesh.     

Drinking water insecurity: water quality and access in coastal south-western Bangladesh

National drinking water assessments for Bangladesh do not reflect local variability, or temporal differences. This paper reports on the findings of an interdisciplinary investigation of drinking water insecurity in a rural coastal south-western Bangladesh. Drinking water quality is assessed by comparison of locally measured concentrations to national levels and water quality criteria; resident’s access to potable water and their perceptions are based on local social surveys. Residents in the study area use groundwater far less than the national average; salinity and local rainwater scarcity necessitates the use of multiple water sources throughout the year. Groundwater concentrations of arsenic and specific conductivity (SpC) were greater than surface water (pond) concentrations; there was no statistically significant seasonal difference in mean concentrations in groundwater, but there was for ponds, with arsenic higher in the dry season. Average arsenic concentrations in local water drinking were 2–4 times times the national average. All of the local groundwater samples exceeded the Bangladesh guidance for SpC, although the majority of residents surveyed did not perceive their water as having a ‘bad’ or ‘salty’ taste.     

Nonmalignant respiratory effects of chronic arsenic exposure from drinking water among never-smokers in Bangladesh

BACKGROUND: Arsenic from drinking water has been associated with malignant and nonmalignant respiratory illnesses. The association with nonmalignant respiratory illnesses has not been well established because the assessments of respiratory symptoms may be influenced by recall bias or interviewer bias because participants had visible skin lesions. OBJECTIVES: We examined the relationship of the serum level of Clara cell protein CC16--a novel biomarker for respiratory illnesses--with well As, total urinary As, and urinary As methylation indices. METHODS: We conducted a cross-sectional study in nonsmoking individuals (n = 241) selected from a large cohort with a wide range of As exposure (0.1-761 microg/L) from drinking water in Bangladesh. Total urinary As, urinary As metabolites, and serum CC16 were measured in urine and serum samples collected at baseline of the parent cohort study. RESULTS: We observed an inverse association between urinary As and serum CC16 among persons with skin lesions (beta = -0.13, p = 0.01). We also observed a positive association between secondary methylation index in urinary As and CC16 levels (beta = 0.12, p = 0.05) in the overall study population; the association was stronger among people without skin lesions (beta = 0.18, p = 0.04), indicating that increased methylation capability may be protective against As-induced respiratory damage. In a subsample of study participants undergoing spirometric measures (n = 31), we observed inverse associations between urinary As and predictive FEV(1) (forced expiratory volume measured in 1 sec) (r = -0.37; FEV(1)/forced vital capacity ratio and primary methylation index (r = -0.42, p = 0.01). CONCLUSIONS: The findings suggest that serum CC16 may be a useful biomarker of epithelial lung damage in individuals with arsenical skin lesions. Also, we observed the deleterious respiratory effects of As exposure at concentrations lower than reported in earlier studies.     

臭氧水处理器在农村小型生活饮用水供水系统中的应用及效果评价

1)目的 :报道了研制的一种适合农村水厂特点的经济、实用、简便易操作、高效的臭氧水处理设备。2 )设计思想及技术路线 :农村水厂的消毒设备必须具备作用迅速 ,运行成本低廉 ,同时自动化程度高、易于操作。臭氧水处理器的技术核心是产生高浓度臭氧并有效地掺混于待处理水中 ,根据用水量的变化 ,自动投加到供水主管路中。3)消毒效果 :加标实验表明 ,在臭氧浓度不低于 0 2mg L时 ,3分钟的接触时间足以杀灭水中的细菌和大肠菌群。现场应用实验结果表明 ,在三个村采集的 2 0个水样细菌总数和大肠菌群均符合生活饮用水水质卫生规范 ,说明臭氧水处理器对大肠菌群和细菌的杀灭作用可靠。 4)讨论及结论 :本研究的创新点在于研制出新型掺混技术 ,效果可靠、作用迅速、程控自动操作、设备自身和运行成本低廉。适合我国国情的农村小型生活饮用水处理系统应用     

安徽省农村生活饮用水卫生现状调查

目的了解安徽省农村生活饮用水卫生现状和水质合格率,为改善农村饮用水提供依据。方法根据安徽省地理、人口等分布情况,确定19个市、县作为调查点,开展农村生活饮用水水源类型、取水方式、水源污染情况、生活饮用水水质监测等调查;依据《农村实施<生活饮用水卫生标准>准则》对水质卫生质量进行评价。结果共调查集中式供水单位303家、分散式供水单位189家;检测水样984份,其中集中式供水水样606份、分散式供水水样378份;生活饮用水水质合格率:二级水为40.96%,三级水为58.03%。结论农村生活饮用水合格率较低,水源污染较重,存在饮水安全隐患。     

水中邻苯二甲酸酯类化合物去除方法实验研究

目的：探讨水中邻苯二甲酸酯类化合物去除方法，并通过筛选确定有效去除工艺。方法：用标准贮备液配制实验溶液，采用4种方法进行实验处理，对处理前后样品进行水质检验。结果：4种处理方法中Ⅳ法对4种异构体的去除率为100％；Ⅱ法为0％－100％不等，而I、Ⅲ法仅对邻苯二甲酸二酯有效果，去除率分别为89．7％和100％。结论：水中邻苯二甲酸酯类化合物去除效果Ⅳ法＞I法＞Ⅲ、I法，Ⅳ法去除效果最好。     

Manganese exposure from drinking water and children's classroom behavior in Bangladesh

Background: Evidence of neurological, cognitive, and neuropsychological effects of manganese (Mn) exposure from drinking water (WMn) in children has generated widespread public health concern. At elevated exposures, Mn has been associated with increased levels of externalizing behaviors, including irritability, aggression, and impulsivity. Little is known about potential effects at lower exposures, especially in children. Moreover, little is known regarding potential interactions between exposure to Mn and other metals, especially arsenic (As).Objectives: We conducted a cross-sectional study of 201 children to investigate associations of Mn and As in tube well water with classroom behavior among elementary school children, 8–11 years of age, in Araihazar, Bangladesh.Methods: Data on exposures and behavioral outcomes were collected from the participants at the baseline of an ongoing longitudinal study of child intelligence. Study children were rated by their school teachers on externalizing and internalizing items of classroom behavior using the standardized Child Behavior Checklist-Teacher’s Report Form (CBCL-TRF).Results: Log-transformed WMn was positively and significantly associated with TRF internalizing [estimated β = 0.82; 95% confidence interval (CI), 0.08–1.56; p = 0.03], TRF externalizing (estimated β = 2.59; 95% CI, 0.81–4.37; p =0.004), and TRF total scores (estimated β = 3.35; 95% CI, 0.86–5.83; p = 0.008) in models that adjusted for log-transformed water arsenic (WAs) and sociodemographic covariates. We also observed a positive monotonic dose–response relationship between WMn and TRF externalizing and TRF total scores among the participants of the study. We did not find any significant associations between WAs and various scales of TRF scores.Conclusion: These observations reinforce the growing concern regarding the neurotoxicologic effects of WMn in children.     

重庆市现制现售饮用水卫生现况调查

目的了解重庆市现制现售饮用水的卫生现状,探讨解决问题办法,规范市场秩序。方法重庆市内18个区县的卫生监督人员经过培训后,用统一的调查表对当地现制现售饮用水基本情况进行横断面调查,以分层随机抽样抽检水质,数据用率进行统计学描述及χ²检验。结果全市18个区县内共有现制现售制水点826个,制水设备持有有效卫生许可批件的有732台,持证率88.62%,小区和学校内的现制现售饮用水制水设备持证率差异有统计学意义（P<0.05）。水质实验室检测62件,合格50件,合格率80.65%,小区和学校内的现制现售饮用水出水水质合格率差异无统计学意义（P>0.05）。结论针对学校和小区的不同管理模式采取合理对策,对现制现售饮用水有效管理,提升重庆市现制现售饮用水卫生现状。     

A performance assessment of arsenic-iron removal plants in the Manikganj district of Bangladesh

In Bangladesh, arsenic contamination of groundwater, microbial contamination of surface water and seasonally variable rainfall make reliable access to acceptable quality drinking water a challenge. Arsenic-iron removal plants (AIRPs) are a relatively inexpensive way of removing arsenic from groundwater for access to safer drinking water. This study evaluated the performance of 21 (of 105) AIRPs installed by a local non-governmental organization (Society for People's Action in Change and Equity) with financial assistance from the Australian High Commission, Dhaka, under the Direct Aid Program of the Australian Government. All AIRPs achieved the Bangladesh standard for arsenic in drinking water of 50 mg L^-1 and 17 achieved the World Health Organization guideline of 10 mg L^-1. The AIRPs removed 87% of influent arsenic, on average. After cleaning, poor arsenic and iron removal was observed for about 2 days due to inadequate residence time. Chemical processes that may influence AIRP performance are also discussed herein, including iron and arsenic oxidation, arsenic co-precipitation with iron, multiple iron additions, interference by organics, and iron crystallization. Effluent faecal coliform counts were generally low, though were slightly higher than influent counts. Overall, AIRPs were shown to possess considerable promise for use in areas with high natural iron where users are concerned about arsenic and/or iron in their drinking water.     

福建省泉州市农村饮水安全工程水质微生物指标分析

目的 了解福建省泉州市农村饮水安全工程（水厂）水质微生物污染状况。方法 于2010-2014年对泉州市5个县（市）621处农村水厂进行调查,同时于枯水期和丰水期采集出厂水和末梢水共2 484份水样进行水质微生物检测。结果 微生物指标总合格率为60.14%,年度合格率在54.58%~64.86%之间。集中式与小型集中式水厂,小型集中式水厂出厂水与末稍水,地表与地下水源水,使用漂白粉、液氯与二氧化氯处理的水质微生物指标合格率分别为70.83%与59.26%,61.20%与57.05%,43.10%与60.23%,54.62%、86.27%与81.82%,各分类统计的合格率差异均有统计学意义（P<0.05）;地下水经完全处理、沉淀过滤、未处理的微生物指标合格率分别为56.25%、59.57%、55.00%,差异无统计学意义。结论 泉州市农村水厂水质微生物指标严重超标。     

2010-2013年青岛市农村生活饮用水卫生现况调查

目的了解掌握青岛市农村居民饮水现状,为政府决策提供技术支持。方法对2010-2012年对全市涉农区市集中式供水工程进行水源类型、水处理方式等基础信息调查和水质采样检测。结果全市农村集中式供水普及率达100%;2010-2012年农村饮用水平均合格率大约为43.44%。结论从2010-2013年水质结果分析,微生物指标是影响水质合格主要指标,原因是多数农村供水工程无相应的消毒设施,部分配备消毒设施的工程消毒不规范造成的。     

烟台市农村地区井水硝酸盐暴露健康风险评估

目的 监测评估2015—2018年烟台市农村地区成年人、婴儿井水硝酸盐的暴露风险状况。方法 对烟台市农村地区1 174口水井硝酸盐浓度进行监测,枯、丰水期各一次,运用χ² 检验等方法对所得数据进行统计分析;同时结合体重、每日饮水量,估算出成年男性、成年女性、孕早期女性、新出生婴儿及三月龄婴儿等不同人群的危险系数(hazard quotient,HQ)。结果 2015—2018年共检测2 348份水样。不同年份、不同采样时段硝酸盐含量差别均无统计学意义;硝酸盐含量中位数(C_exp50)为 17.8 mg/L;较高暴露C_exp95为53.4 mg/L;成年男性、成年女性、孕早期女性的HQ₅₀、HQ₉₅均超过1;新出生婴儿的HQ₅₀、HQ₉₅分别为11.47和34.41;三月龄婴儿的HQ₅₀、HQ₉₅分别为10.14和30.41。结论 烟台市农村地区井水中硝酸盐含量稳定,成年人是饮水硝酸盐暴露的中等风险人群;新出生婴儿、三月龄婴儿的饮水硝酸盐危险系数较高,是高风险群体,需引起高度重视。     

邳州市农村饮用水水质全分析本底调查

目的:了解邳州市农村饮用水水质本底值,为农村改水提供依据。方法:选择具有代表性的农村饮用水水厂5个,按照GB/T5750-2006《生活饮用水标准检验方法》进行饮用水水质全分析(103项),用GB5749-2006《生活饮用水卫生标准》进行评价。结果:5个水厂均未按照要求进行规范消毒,除1个水厂大肠菌群和1个水厂贾第鞭毛虫稍有超标外,其他指标均符合生活饮用水卫生标准。结论:邳州市农村地下水源水质状况良好,只要加强管理,规范消毒,完全可以达到生活饮用水卫生标准。     

2018年陕西省市政供水消毒现状

目的了解陕西省2018年城市市政供水水质消毒状况和微生物指标污染情况,为改善城市生活饮用水水质提供依据。方法收集2018年陕西省城市市政供水水质监测数据,参照《生活饮用水卫生标准》(GB5749-2006)对消毒剂余量、消毒副产物和微生物指标达标率进行分析。结果2018年陕西省市政供水微生物指标整体达标率为91.66%,消毒剂余量达标率为93.56%;地下水水质微生物指标整体达标率高于地面水(χ^2=30.625,P<0.001),消毒剂余量达标率也高于地面水(χ^2=6.456,P=0.011);出厂水中消毒剂余量达标率低于末梢水(χ^2=41.091,P<0.001)和二次供水(χ^2=20.999,P<0.001);消毒剂余量达标的水厂微生物指标达标率较高(χ^2=83.022,P<0.001);消毒副产物中,亚氯酸盐、氯酸盐、三氯甲烷和四氯化碳达标率分别为98.33%、99.38%、99.81%和100.00%。结论影响陕西省城市生活饮用水水质微生物指标达标率的主要因素是消毒剂余量。建议政府持续加大管理力度,督促供水单位加强水质净化消毒,规范消毒程序,确保消毒剂投放充足、适量。     

直饮水和涉水产品的微生物污染状况调查

目的　了解深圳市直饮水和涉水产品的微生物污染状况 ,为此类产品的卫生监督管理提供依据。方法　随机抽取直饮水样品 93分和涉水产品样品 2 7份 ,参照国家《生活饮用水卫生规范》、《饮用水安全产品卫生规范》的检验方法进行检验。结果　深圳市直饮水和涉水产品的细菌总数、霉菌污染严重。细菌总数不合格率为 2 6 9% ,霉菌不合格率为 7 5 %。结论　直饮水和涉水产品的细菌污染与生产环节及涉水产品的类型和质量有关     

巢湖市农村生活饮用水现状调查

目的:了解农村生活饮用水现状,为加快农村自来水发展提供可靠依据.方法:对巢湖市农村镇区、行政村进行普查,并进行系统分析.结果:巢湖市农村总人口4323583人.有集中式供水设施229个,饮用人口1466590人,占33.92%;分散式供水饮用人口2856993人,占66.08%,水源类型包括深水井、浅水井、泉水、江河湖泊水库水、塘水和其他,其中,74.77%的人饮用浅井水.结论:巢湖市农村集中式供水尚不够普及,应加快发展,同时应加强监管.     

2012年北京市怀柔区农村饮水安全工程集中式供水水质检测结果

目的为近一步了解北京市怀柔区农村饮水水质卫生状况,保证农村饮水安全,提高农村居民的生活质量。方法分层随机抽取60个监测点,每个监测点在丰水期和枯水期各检测1次,每次采集出厂水和末梢水各1件,全年共检测水样240件。结果 2012年农村饮水安全工程集中供水240件,水样合格率为83.8%;枯、丰水期水质的差异有统计学意义（χ2=8.85,P〈0.01）;微生物学指标中总大肠菌群、耐热大肠菌群不同采样时间合格率差异有统计学意义（χ2=7.47,P〈0.01;χ2=7.92,P〈0.01）;感官性状和一般化学指标以及毒理学指标全部合格。结论 2012年怀柔区农村饮水集中式供水水质总体状况较好,超标项目依旧主要集中在微生物学指标,今后应加大对微生物指标的监测力度以及消毒设备的投资力度,进一步改善农村水质卫生状况,保障农村居民身体健康。     

山西省出生缺陷高发区居民饮水中硝酸盐和亚硝酸盐含量研究

目的了解山西省出生缺陷高发地区饮水中硝酸盐和亚硝酸盐含量。方法选择山西省太原市、太谷县和平定县作为研究现场,采集当地居民不同类型的饮用水测定硝酸盐和亚硝酸盐含量。结果研究地区饮水中硝酸盐平均含量为3·5mg/L,有4·0%的样品超过我国的饮用水卫生标准。井水中的硝酸盐含量(5·1mg/L)高于自来水(2·7mg/L)。饮水中亚硝酸盐平均含量为0·004mg/L,以泉水含量最高(0·015mg/L)。结论研究地区居民饮水中硝酸盐和亚硝酸盐含量并没有显著高于文献报道的其它地区。饮水中硝酸盐和亚硝酸盐暴露在山西省出生缺陷高发中的作用可能不大。     

句容市区域供水对农村饮水卫生质量的影响

目的了解实施区域供水前后的农村饮用水卫生状况,评价区域供水对农村饮水卫生质量的影响,为进一步推进农村改水工作、保障村民生活饮用水安全提供科学依据。方法对句容市区域供水前后的农村自来水厂的出厂水、末梢水进行枯水期和丰水期水质卫生监测与评价。结果该市实施区域供水前后的农村饮用水水质合格率分别为28．75％、91．25％,出厂水好于末梢水。不合格项目为浑浊度、耗氧量、菌落总数、总大肠菌群等指标。区域供水前后的农村饮用水水质卫生合格率差异有统计学意义（P〈0．01）。结论该市区域供水对提高农村饮用水水质卫生质量效果明显,但部分末梢水仍然存在卫生安全隐患,建议在推广农村区域供水时,需加强管网改造,以确保饮水的卫生质量。     

Multipathway risk assessment of trihalomethane exposure in drinking water of Lebanon

The toxicological risks and lifetime cancer risks of trihalomethanes through oral ingestion, dermal absorption, and inhalation exposure from tap water in selected regions in Lebanon are estimated. Existing trihalomethane concentrations do not pose any non-carcinogenic and developmental risks in the exposed population via oral ingestion. Among the three pathways, residents have a higher risk of cancer through oral ingestion than through the other two pathways. The lifetime cancer risk through oral ingestion for dibromochloromethane makes the highest contribution to total risks, followed by bromodichloromethane, bromoform, and chloroform. The total multipathway cancer risk analysis suggests that no cancer risks exist during the summer and winter seasons; however, in the spring the total cancer risks exceeds the USEPA acceptable level of 10^-6 by a factor of 10.7.