Disinfection Byproducts and Their Precursors in Drinking Water Sources:Origins,Influencing Factors,and Environmental Insights

Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as they tend to be laborious,time-consuming,or technically difficult.Disinfection byproducts(DBPs)are a family of well-known secondary pollutants formed by the reactions of chemical disinfectants with DBP precursors during water disinfection treatment.Since DBP precursors have various origins(e.g.,natural,domestic,industrial,and agricultural sources),and since the formation of DBPs from different precursors in the presence of specific disinfectants is distinctive,we argue that DBPs and DBP precursors can serve as alternative indicators to assess the contamination in water sources and identify pollution origins.After providing a retrospective of the origins of DBPs and DBP precursors,as well as the specific formation patterns of DBPs from different precursors,this article presents an overview of the impacts of various natural and anthropogenic factors on DBPs and DBP precursors in drinking water sources.In practice,the DBPs(i.e.,their concentration and speciation)originally present in source water and the DBP precursors determined using DBP formation potential tests—in which water samples are dosed with a stoichiometric excess of specific disinfectants in order to maximize DBP formation under certain reaction conditions—can be considered as alternative metrics.When jointly used with other water quality parameters(e.g.,dissolved organic carbon,dissolved organic nitrogen,fluorescence,and molecular weight distribution)and specific contaminants of emerging concern(e.g.,certain pharmaceuticals and personal care products),DBPs and DBP precursors in drinking water sources can provide a more comprehensive picture of water pollution for better managing water resources and ensuring human health.

Economic significance and environmental impacts of the Song Dam Drinking Water Project(SDDWP)in Garhwal Himalaya

With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDWP)is proposed to provide ample drinking water to Dehradun City and its suburban areas.This paper examined economic significance and environmental impacts of the SDDWP in Garhwal Himalaya,India.To conduct this study,we collected data from both primary and secondary sources.There are 12 villages and 3 forest divisions in the surrounding areas of the proposed dam project,of which 3 villages will be fully submerged and 50 households will be affected.For this study,50 heads of the households were interviewed in the 3 submerged villages.The questions mainly focused on economic significance,environmental impacts,and rehabilitation issues of the dam project.The findings of this study indicate that economic significance of the dam project is substantial,including providing ample water for drinking and irrigation,contributing to groundwater recharge,creating job opportunities,and promoting the development of tourism and fisheries in the Doon Valley.In terms of the rehabilitation of the affected people,there are only 50 households in need of rehabilitation.Currently,the arable land of these affected people is not sufficient to sustain their livelihoods.The entire landscape is fragile,rugged,and precipitous;therefore,the affected people are willing to rehabilitate to more suitable areas in the Doon Valley.Moreover,it is essential to provide them with sufficient compensation packages including the compensation of arable land,houses,cash,common property resources,institutions,belongingness,and cultural adaptation.On the other hand,the proposed dam project will have adverse environmental impacts including arable land degradation,forest degradation,loss of fauna and flora,soil erosion,landslides,and soil siltation.These impacts will lead to the ecological imbalances in both upstream and downstream areas.This study suggests that the affected people should be given sufficient compensation packages in all respects.Afforestation programs can be launched in the degraded areas to compensate for the loss of forest in the affected areas.

Gross Alpha and Beta Activities and Related Lifetime Risks Assessment Due to Ingestion of Drinking Water from Different Sources in the District of Abidjan, Cote d’Ivoire

Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the objective of this study was to assess the risk of cancer due to the ingestion of alpha and beta emitting radionuclides in the different types of water consumed in the region. A total of 63 water samples with 43 tap water samples, 5 bottled mineral water and 15 sachet water samples was collected and taken to GAEC laboratory for analysis. The low background Gas-less Automatic Alpha/Beta counting system (Canberra iMaticTM) was used to determine alpha and beta activity concentrations. Activity concentrations of both gross alpha and gross beta obtained in water sample were respectively lower than the WHO recommended limits of 0.1 Bq/l and 1 Bq/l. Also, the annual effective dose and total equivalent effective dose found in mineral bottled water samples were higher than in other types of water. The assessment of radiological lifetime risk has shown values of cancer risk due to ingestion alpha and beta emitters lower than recommended limit. These results indicate that there is no health hazard associated to consumption of water in the District of Abidjan.

A review of physicochemical and biological contaminants in drinking water and their impacts on human health

Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a review of selected water contaminants and their impacts on human health.The World Health Organization(WHO)guidelines and regional standards for key contaminants were used to characterise water quality in the European Union and UK.The concept of safe drinking water was explained based on the non-observed adverse effect level,threshold concentrations for toxic chemicals,and their total daily intake.Various techniques for monitoring water contaminants and the drinking water standards from five different countries,including the UK,USA,Canada,Pakistan and India,were compared to WHO recommended guidelines.The literature on actual water quality in these regions and its potential health impacts was also discussed.Finally,the role of public water suppliers in identifying and monitoring drinking water contaminants in selected developed countries was presented as a potential guideline for developing countries.This review emphasised the need for a comprehensive understanding of water quality and its impacts on human health to ensure access to clean drinking water worldwide.

Study on the Possibility of Raw Seawater into Drinking Water—A Religious Water Literacy

This paper explores the conversion of raw seawater into drinking water from a religious water literacy (RWL) perspective. RWL is here defined as a socially just water literacy that is based on the respect for the dignity of life of all living beings on the Earth. It discusses the importance of sustainable water sources and proposes purification methods. That is, the study aims to show a brief outline of the drinking water source (inland waters;mainly river water) and their purification technologies in recent times and today and propose the purification method (Freezing-Thawing-UV method) in case of taking the seawater as the source. And, it emphasizes the need for dialogue and cooperation between countries in order to proceed. The paper also discusses the relationship among religion, culture, and civilization, and highlights the similarities between Marx’s historical materialism and Umesao’s ecological view. It further discusses the importance of water purification technology, separation methods, and the potential for seawater as an energy source. The paper concludes by discussing the importance of dialogue, communication and understanding environmental decision-making. In order to carry them forward, it is convinced that citizens in the world are nothing but people with self-awareness of “Bodhisattvas of the Earth” as identities. As a result, the new findings that suggest the possibility of raw seawater into drinking water from a religious water literacy perspective through the lens of Kawakatsu’s maritime view have been obtained.

Impact of the Condition of Drinking Water Supply Networks on the Quality of Water Intended for Consumption: The Case of the Network in the Commune of Daloa (Central West of Côte d’Ivoire)

The potability of drinking water depends not only on the source and the treatment system, but also on the quality of the waterworks. In fact, the quality of drinking water is considerably degraded by the dilapidated state and lack of maintenance of drinking water networks. In Côte d’Ivoire, the majority of drinking water networks in the various towns are ageing. In Daloa, despite the efforts made by the company in charge of water treatment and distribution to make the water drinkable, the water at consumers’ taps is often colored, has an unpleasant aftertaste and settles after collection. As a result, people are concerned about the potability of tap water, and some are turning to alternative sources of drinking water of unknown quality. In order to determine the factors responsible for the deterioration in water color and taste, as well as the sectors of the network most affected, a diagnosis of the network’s equipment was carried out. Water samples taken from the network were analyzed for color and turbidity. The diagnosis revealed that most of the equipment (suction pads, valves, drains and fire hydrants) is outdated and irregularly maintained. Analyses show that the water is more colored in cast-iron and PVC pipes than in asbestos cement pipes. Coloration values in the network range from 0 to 27 UVC for asbestos cement pipes, from 15 to 56 UCV for ductile iron pipes, and from 11 to 102 UCV for PVC pipes. On the over hand, turbidity values vary from 8.02 to 3.32 NTU for ductile cast iron pipes, 8.51 to 16.98 NTU for asbestos cement pipes and 0.9 to 6.98 NTU for PVC pipes. Old cast-iron pipes release ferric ions on contact with water, degrading their color. Old cast-iron pipes release ferric ions into the water, degrading its color. The high color values observed in the vicinity of drains are thought to be due to irregular maintenance of the network. In fact, after network maintenance, a reduction rate ranging from 2% to 73% is observed for turbidity, while for color, the rate varies from 5% to 72%. In short, the network’s obsolescence and irregular maintenance contribute significantly to the deterioration of water quality.

Health Risk Assessment on Rural Drinking Water Safety —A Case Study in Rain City District of Ya’an City of Sichuan Province

Taking Rain City District of Ya’an for example, this paper based on ComGIS (Component Object Model Geographic Information System) platform takes comprehensive and systematic detection on the exposure dose of chemical carcinogens and non-carcinogens from drinking water sources in this region and discusses health risk assessment of single factor and the whole health risk assessment. As, Hg, Cr, Pb, Cd and fluorides in some drinking water sources of Rain City District are analyzed according to Standards For Drinking Wa-ter Quality (GB5749-2006). A health risk assessment model called USEPA is also applied to drinking water health risk assessment and management countermeasure is proposed. The results show that the greatest health risk for individual person per year is caused by Cr(VI). The health risk of carcinogens is much higher than that of non-carcinogens: the greatest risk value due to non-carcinogen pollutants is caused by fluoride (F), achieving 1.05×10-8/a. The ranking of risk values due to non-carcinogen pollutants by drinking water is Pb>fluoride (F)>Hg, within Pb accounting for 44.77%, fluo-ride (F) accounting for 34.30% and Hg accounting for 20.92%. The average individual carcinogenesis annual risk of Cr(VI) is the greatest, achieving 8.91×10-4/a. The ranking of risk value due to chemical carcinogen by rural drinking water of Ya’an is Cr6+>As>Cd, within Cr6+ accounting for 91.12%, As accounting for 5.89% and Cd accounting for 3.00%. Based on this, the strategy and measures of the health risk management are put forward. This study has worked efficiently in practice. Compared with the same kind of methods which have been found, the paper has the outstanding results for the health risk assessment of the rural drinking water safety.

Integrated Control of Agricultural Non-point Source Pollution to Provide Safe and Healthy Drinking Water for Rural Areas

Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source pollution and the current situation of agricultural non-point source pollution prevention and control in China. In view of the serious agricultural non-point source pollution in water environment of Guangxi and the difference in quality of drinking water between urban and rural areas,it came up with recommendations for strengthening agricultural non-point source pollution prevention and control from scientific distribution,linked operation and maintenance,popular science education,and legal system construction,to guarantee safe and healthy drinking water in rural areas.

Protection Planning for Rural Centralized Drinking Water Source Areas in Chongqing

Protection planning is made for rural centralized drinking water source areas according to current situations of rural drinking water and existing problems of centralized drinking water source areas in Chongqing,and in combination with survey,analysis and evaluation of urban-rural drinking water source areas in whole city.There are engineering measures and non-engineering measures,to guarantee drinking water security of rural residents,improve rural ecological environment,realize sustainable use of water resource,and promote sustainable development of society.Engineering measures include conservation and protection of water resource,ecological restoration,isolation,and comprehensive control of pointsource and area-source pollution.Non-engineering measures include construction of monitoring system for drinking water source area,construction of security information system for rural centralized drinking water source area,and construction of emergency mechanism for water pollution accidents in rural water source areas.

ComGIS-Based Early Warning System of Rural Drinking Water Safety in Ya’an City of Sichuan, China

According to characteristic index of spatial-temporal variability of rural drinking water safety in Ya’an City of Sichuan, China, such as water quantity, water quality, convenience degree and guaranteed rate, etc., this study elaborated the basic framework, model’s methodology structure in early warning system of rural drinking water safety on the basis of ComGIS and initially designed information collection, search and re-trieval, evaluation and analysis of factors, dynamic prediction and dynamic early-warning and functions of guidance and management in this system. The design of this system provided scientific basis to grasp the state of rural drinking water safety timely, release early warning information and properly take necessary control measures, etc. The evaluation results showed that the overall trend was getting better. It proved that the rising pressure value and response value were main reasons which caused the rising evaluation value of rural drinking water safety.

Temporal-spatial Analysis on Urban and Rural Drinking Water Health Monitoring of Tianjin in 2013

Objective Grasp quality and health status of drinking water, and provide scientific basis for decision making of health administrative de- partment. Method According to the Standards for Drinking Water Quality （ GB 5749 -2006）, monitoring results of Tianjin urban and rural drinking water health in 2013 were evaluated, and software SPSS 20.0 and GeoDa was used for temporal-spatial analysis on water quality. Result There were 2 882 copies of monitoring samples in total, in which both finished water and tap water of urban district were qualified, while qualified rates of tap water and secondary water supply from the county were respectively 86.36% and 93.91%, and major exceeding indexes were pH and total number of colonies. Qualified rates of tap water and secondary water supply from the county had difference（x2 = 1 576.875, P 〈0.01 ）. Quality of tap water（ X2 = 5.425, P 〉 0.05） and secondary water supply （X2 = 16.009, P 〉 0.05） was stable at temporal distribution （ January-December）, but spatial distribution of tap water had certain regional difference（x2 = 1 255.802, P 〈0.01 ）. Conclusion General quality situation of Tianjin urban and rural drinking water was better, but qualified rate of water quality in some counties was lower, which had safety risk and threatened the health of residents in the corresponding county. The related departments should enhance the supervision and management of drinking water supply, im- prove supply water quality, strengthen water quality monitoring, and guarantee drinking water safety. Geographic information system can better real- ize visualization of drinking water quality monitoring information.

Design of Water Disinfection Scheme for Rural Drinking Water Safety Project

As further promotion of the rural drinking water safety project in whole country, small villages in vast countryside have been or will be equipped with safety drinking water project. We analyzed necessity of the rural drinking water disinfection, discussed disinfection method suitable for rural drinking water characteristics, and put forward disinfection schemes for different water supply sources.

A Study on the Microbial Quality of Drinking Water in Rural Areas of Mazandaran Province in North of Iran (2011)

Backgrounds: One of the fundamental needs of a community is to have an access to healthy and safe drinking water. The lack of a concentrated accessibility to health facilities and services is among the serious problems facing villagers in the rural areas. The aims of this research was to investigate the drinking water quality of the villages in Babol township suburbs in north of Iran. Materials and Methods: In this cross-sectional descriptive study, a total of 140 water samples were taken from the water distribution network in16 villages for the low and high-rain seasons in sterile glass bottle. The microbial quality of gathered samples were determined based on standard methods in laboratory. Statistical analysis of the results was performed using a SPSS16 statistical software. Findings: Based on obtained results 13.6% of the samples were contaminated to coliform and 20% to fecal coliform bacteria. The residual chlorine in 12.5% of the samples were between 0.2 to 0.8 mg·L-1 and the PH in total samples were between 6.8 to 7.8. There were no signs of any contamination for 32.86% of the analysed samples which water resources is located to a distance of more than 30 m to the contamination sources. In addition, 43.1% of the samples taken from the water resources with no plumbing system, have had a fecal contamination. Conclusions: Considering the results achieved, the microbial quality of the drinking water of the studied villages classified as “moderate” status. For more water supply there is not sufficient residual chlorine in most cases. Poor sanitation of water supply is most causes of water contamination. It is therefore strongly recommended that sanitation measures are made to protect water resources from the contamination.

Evaluation Model of Rural Drinking Water Project Based on Entropy Weight and Fuzzy Comprehensive Evaluation Method

Based on Measures for Assessment of Rural Drinking Water Standard Raising Action in Zhejiang Province,this study established an evaluation system for rural drinking water project in Zhejiang Province,covering three primary indicators of project construction,project management and project performance,and 18 secondary indicators.It proposed an evaluation model based on entropy weight and fuzzy evaluation method.It solved the problems of the objectivity of the indicator weight and the quantification of the indicators,and can well achieve the coordination and unity of fuzziness and accuracy.Using this model,it evaluated a rural drinking water project in a county and concluded that both accuracy and feasibility of the model are high.

Research on the Risk Associated with Rural Drinking Water Safety Based on Catastrophe Theory

In this study, based on the analysis of the catastrophic risk of rural drinking water, with the representative villages in Ya’an as study objects and setting the four evaluation standards: water quality, water quantity, the Guarantee Probability for water Supply and the Convenience Level of the Access to Water Supply as the ba- sic framework, a Rural Drinking Water Safety Assessment was developed (RDWSA). Research showed that Catastrophe Theory was applicable in the RDWSA. Adding RDWSA based on Catastrophe Theory to the supportive system for decision-making in Ecological Hydrographic Management Decision Support System of Ya’an helped obtain the rank and results of RDWSE by the automatic calculation of programs, which could assist the risk assessment and risk management associated with rural drinking water in Ya’an.

Analysis and Discussion on Property Right of Rural Drinking Water Projects

Since rural drinking water projects have diversified investment subjects,complex form,and lacks property right system and policy at national level,there are many difficulties in determining property right of projects in many areas.This not only puzzles competent authorities and specific management institution,but also is unfavorable for long-term full play of project benefit.Combining related laws,regulations,and policies,this paper analyzed and discussed property right of rural drinking water projects.It proposed establishing usufructuary right to replace division of property right,in the hope of helping improve management of rural drinking water projects.

Quality and Method of Management of Drinking Water in Rural Areas in Benin: Case of Artesian Drills of Dogbo Ahomey in the Borough of Tota, Municipality of Dogbo

The objective of this study is to assess the quality of the artesian borehole water consumed by the population of the village of Dogbo Ahomey in order to prevent pathologies on the populations. Methodology and Results: The household surveys were supplemented by a campaign to analyze the water samples in the laboratory. The samples were analyzed according to the standardized methods of the American Public Health Association (APHAAWWA-WPCF, 1994). A total of twenty (20) physico-chemical parameters and four (04) microbiological parameters were used to assess the quality of the different water samples. The results of the physico-chemical analysis showed that the water samples studied present values that are below the standards recommended by the WHO and by the Beninese standards for the quality of drinking water (Standards, 2001). From a microbiological analysis point of view, of the four samples studied, two show strong pollution by germs. This could be a significant health risk for households who take water from these sources to meet their needs.

Problematic of Drinking Water Access in Rural Area: Case Study of the Sourou Valley in Burkina Faso

Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development. The study aims to investigate the drinking water quality and the factors affecting this quality in the Sourou valley in Burkina Faso. A total of 135 water samples were collected in sterile glass bottles during the dry seasons 2007, 2008, and 2012 from 10 drillings and 5 wells. Fifteen physicochemical parameters and two fecal pollution indicators (Escherichia coli and fecal Coliforms) were monitored based on laboratory standard methods. Datas were analyzed, using the Student t’ test and XLSTAT 7.5.2 statistical software. From results obtained, water quality was related to water source and sampling period as well (p 0.0001). 30% of drillings provided water with nitrates concentration over the World Health Organization (WHO) guideline value. High turbidity was also observed for some drillings. Moreover, 90% of drillings showed water total hardness largely over the WHO threshold value. Water from drillings were exempt of fecal pollution, contrasting with the wells one which appeared uniformly polluted with concentrations exceeding sometimes 103 and 104 CFU/100 ml for E. coli and fecal Coliforms, respectively. Field investigations showed a preference of wells as drinking water source, and that appeared related to the lack of self-management of drillings and to cultural considerations. Overall, this study highlighted that a regular survey of water quality, management of protection zones around drinking water sources, sensitization on water resources self-management, hygiene and health issues, and providing appropriate household disinfection methods could help advancing to reach an effective safe drinking water access for rural populations in the country.

Factors Influencing on Drinking Water Source Selection in Rural Areas of the Bengal Region

The arsenic contamination of underground water is a serious problem in rural areas of the Bengal region, where the water pipeline supply is not equipped. Those, who suffer from the contamination are mainly in the poorest sector. In the region, the selection of drinking water sources is done by women. The local traditional custom of Parda may restrict women＇s behavior. In this paper, a quantitative way of evaluating women＇s psychological stress is proposed, and mechanisms of women＇s water selection are analyzed using behavioral model. Ultimately, the more acceptable ways of installing water facilities to local people in each village are discussed.

Renewable Energy Powered Membrane Process for Removal of Excess Fluoride Ions and Safe Drinking Water Supply in Rural Areas in Senegal

The analysis results made on drinking water from the rural areas of Kaolack,Diourbel and Fatick central region of Senegal showed the excess of fluoride and chloride ions.Depending on the area,the fluoride concentration in the water can reach 3.5 mg/L.The values obtained are completely above of WHO(World Health Organization)limits.The objective of this study is to assess the performances of membrane filtration units powered by renewable energies for fluoride and salinity excess removal in remote village in Senegal.Many membrane filtration units have been installed in rural areas of regions such as Kaolack,Fatick and Diourbel.These membrane filtration units are equipped by the LPRO(Low Pressure Reverse Osmosis)membranes with 9 m^(2)of surface.A rejection rate of fluoride and chloride ions obtained is 99.33%and 95.25%respectively.The conversion rates are ranged from 45%to 65%.These results clearly show that membrane processes can be used in Africa,especially in isolated rural areas,with the combination of renewable energies.Currently,more than twenty membrane filtration units are installed in Senegal and provide drinking water of very good quality for populations living in rural areas.The prospect is to expand it on a larger scale,which is already underway,with the construction of a desalination plant in Dakar.