SOS: Drinking water

We have analyzed the modern, extremely critical situation with the quality of drinking water. We have substantiated the urgency of existing approaches to the assessment of drinking water quality and the necessity of introducing a new concept of drinking water standards. We have set out fundamentally new approaches to the assessment of its quality. We have presented the new State Standard of Ukraine for drinking water, whose legalization will make it possible to provide the population with drinking water—biologically and physiologically safe for human organism.     

Verification of existing regulatory documents when assessing the quality of sources of centralized drinking water supply

The article has considered versions for classification of the water quality of surface drinking water sources. The article has demonstrated the verification results of a draft new state standard using as an example assessments of the quality of a surface sources of centralized drinking water supply. A comparative analysis has been conducted for its application concurrently with existing regulatory documents.     

Heavy metals in drinking waters from Mount Amiata (Tuscany, Italy). Possible risks from arsenic for public health in the Province of Siena

Concentrations of As, Al and some heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb) were measured in drinking waters from Siena and Grosseto districts, South Tuscany, Italy. The analysis, performed mostly by electrothermal activated atomic absorption spectroscopy equipped with graphite furnace, and in some cases high-resolution inductively coupled plasma mass spectrometry, indicated that concentrations of the elements were generally far below the maximum allowed concentration (MAC). However, the concentration of As in some of the waters at sources or at the terminals of the water webs was relatively high (largest value, 14.4(2) microg/l) when compared to the MAC(As) value (10 microg/l, December 25, 2003; Italian Law). Relatively high concentrations of some metals had been detected in a few samples from the ends of the distribution webs, when compared to values at sources. These effects are probably due to leaching from metal pipes. A general 'metal index' (MI) for drinking water, which takes into account possible additive effects of N heavy metals on the human health that helps to quickly evaluate the overall quality of drinking waters, is introduced in this paper as MI=?(i=1,N)[C(i)/(MAC)(i)]. Samples from Ermicciolo spring and Siena water web had MI values of 1.1 and 1.3, respectively, showing that the quality of drinking water in town is somewhat worse than that at one of the main sources, at least regarding the 12 elements taken into account.     

Adaptation and evaluation of the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) for use as an effective tool to characterize drinking source water quality

Protecting drinking source water quality is a critical step in ensuring a safe supply of drinking water. Increasingly, drinking source water protection programs rely on the active participation of various stakeholders with differing degrees of water science knowledge. A drinking source water quality index presents a potential communication and analysis tool to facilitate cooperation between diverse interest groups as well as represent composite water quality. We tested the effectiveness of the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) in capturing expert assessments of drinking water quality. In cooperation with a panel of drinking water quality experts we identified a core set of parameters to reflect common source water concerns. Drinking source water target values were drafted for use in the index corresponding to two basic treatment levels. Index scores calculated using the core parameter set and associated source water target values were strongly correlated with expert assessments of water quality. We recommend a modified index calculation procedure to accommodate parameters measured at different frequencies within any particular study period. The resulting drinking source water CCME WQI provides a valuable means of monitoring, communicating, and understanding surface source water quality.     

Standardized and unified methods for determining phenols in natural and drinking waters and main trends of their development

This paper presents MAC (maximum admissable concentration) values of phenol and its derivatives in natural and drinking waters specified in the normative documents of Ukraine, Russia, the USA, Canada, Great Britain, and international organizations WHO and EU, and also provides data on standardized and unified methods for determining phenols at the MAC level. This paper has discussed directions of the development of techniques for determining phenols during the last fifteen years that are based on preliminary extractive or sorptive concentration and subsequent detection using photometric, gas chromatographic, fluorometric, and kinetic techniques of analysis, and also the high performance liquid chromatographic (HPLC) method with electrochemical and flame ionization detection.     

EPA policies to protect the health of consumers of drinking water in the United States

In the United States our objective is to protect drinking water at the source,during treatment and during distribution. In 1975 interim regulations for bacteria and turbidity, 10 inorganic chemicals, 6 organic chemicals end radionuclides were promulgated. In 1979 National Seccndary Regulations for substances affecting the aesthetic quality of water were promulgated. In 1979 trihalomethanes were added, The United States is engaged in comprehensive revisions of the National Primary Drinking Water Regulations.The areas of our most significant concern include detection and control of contamination of ground waters by organic chemicals resulting from improper waste disposal practices, a reassessment of microbiological regulations and toxicity of disinfectant by-products and a major effort to deal with corrosion-related contamination of drinking water during distribution. We are evaluating the issue of a granular activated carbon requirement for contaminated surface waters. A program to assure the quality of direct and indirect additives to drinking water has also been initiated. Part of this activity will include determination of the contaminants and by-products associated with the use of various water treatment chemicals and pipe materials.     

Basic Principles of Comprehensive Biotesting of Drinking Water and Point System Classification of Water Quality

Basic principles of forming test systems for biotesting of natural and drinking waters, and the factors affecting test-systems during the biotesting procedure have been studied. New directions of selecting sensitive test reactions of organisms and test criteria for the quality assessment of natural and drinking waters based on the results of comprehensive biotesting are proposed. The universal point system for drinking water quality estimation was developed. It is based on summation of biotesting results using 4–5 species of animal and plant test-organisms of different systematic and trophic levels. In addition, the total toxicity index of water samples under investigation was also developed. The findings were used in the preparation of the State Standard of Ukraine “Quality of water. Comprehensive biotesting of natural water. Requirements to the selection and cultivation of test organisms. Water quality classification based on the point system”.     

Development of the revised drinking water standard for chromium

Comprehensive regulations are being developed to limit human exposure to contamination in drinking water by the United States Environmental Protection Agency (EPA) under the authority of the Safe Drinking Water Act (SDWA). These regulations are being developed in several phases and include synthetic organic chemicals, inorganic chemicals, microbiological contaminants and radionuclides. This paper addresses the fundamental concepts and approaches used by EPA in setting drinking water regulations and how EPA is using these concepts to revise the drinking water standard for chromium.     

Potential impact of chlorination of Sandy bottom swimming areas on drinking water sources

The concentrations of trihalomethanes and haloacetic acids, disinfection by‐products (DBPs) of chlorine, were measured in sandy bottom swimming areas to determine their potential impact on surface and ground water that are sources of drinking water. Total trihalomethanes and individual haloacetic acid concentrations in several swimming area samples were higher than the drinking water standards (current and proposed). Individual trihalomethanes (except bromoform) also exceeded ground and surface water release standards. No release standard exists for haloacetic acids. The DBPs, while exceeding standards, would be diluted by the ground water and microbially degraded prior to reaching the drinking water plant. So while DBPs from swimming areas contributed to groundwater concentrations, the current drinking water standards could still be met using source waters impacted by chlorinated swimming areas. It is suggested, though, that any release of chlorinated DBPs to surface and ground water be minimized to obtain the highest quality water sources for drinking water.     

Occurrence of filamentous fungi and yeasts in three different drinking water sources

In order to determine the occurrence of fungi in different drinking water sources and capture variability in terms of matrix composition and seasonal effects, surface water, spring water, and groundwater samples were collected in numerous sampling events. The occurrence and significance of fungi detected in the different water sources are reported and discussed in terms of colony-forming units per millilitre and by the identification of the most frequently detected isolates, at the species level, based on morphology and other phenotypic characters. All the samples were also analyzed in terms of total coliforms and Escherichia coli that are widely monitored bacteria considered as microbiology indicators of water quality. All the groundwater samples showed significantly lower levels of total coliforms, E. coli, and fungi compared to the surface and spring water samples. No significant correlations were found between the levels of fungi detected in all the matrices and the physico-chemical parameters and bacteria regularly monitored by drinking water utilities. Fifty-two fungi isolates were identified in this study, most of which have never been described to occur in water sources. The results obtained show that fungi occur widely in drinking water sources and that further studies should be conducted to address their biodegradation potential as well as if the drinking water treatment processes currently used are effective in removing these organisms and the potential secondary metabolites produced.     

基于可直饮目标的城市二次供水改造经验探讨

保障饮用水安全是关系到国计民生的重要问题,也是全面建设小康社会的重要考核指标。深圳和上海分别提出了到2025年和2035年生活饮用水可直饮的目标,通过梳理两个城市近年来改善、提升二次供水水质的具体措施和情况,总结了二次供水改造模式和成功经验。沪、深两市采用"政府推动、市区联手,统筹安排、分步实施,居民自愿、属地管理"等关键措施,逐步推进二次供水改造工作,并在改造完成后强化生活水池(箱)的清洗消毒工作,实现供水企业管水到表,保障供水安全。     

Electrocoagulation purification of water of Cr6+ compounds

The process of the electrocoagulation purification of water containing chromium, depending on pH, Cr⁶⁺ concentration, ions of metal impurities and ratios Fe²⁺ : Cr⁶⁺ have been investigated. We have found the upper boundary of chromium concentrations (150 mg/dm³) whereby its residual content in water does not exceed MAC for the discharge to the complex of facilities of water disposal. It has been shown that ions of metal impurities present in the water in electrocoagulation are removed together with chromium ions.     

Detection of enteroviruses in treated drinking water

This study deals with the routine monitoring of drinking water for the presence of enteroviruses, over a period of 1 year. A rapid and simple method was employed for the simultaneous detection and typing of enteroviruses in large-volume water samples. This included an integrated cell culture/nested PCR approach, followed by restriction enzyme analysis. The two drinking water supplies studied were derived from acceptable quality surface water sources using treatment processes, which conform to international specifications for the production of safe drinking water. Enteroviruses (predominantly coxsackie B viruses) were detected in 11% and 16% of the drinking water samples from two treatment plants, respectively. This study confirms that acceptable water quality indicators do not necessarily reflect the virus content of drinking water.     

Vulnerability of hand-dug wells in the core area of Akure,Nigeria

Hand-dug wells (HDWs) are a major source of water supply in developing nations. This is consequent upon the failure of government to provide safe water to the people. This paper looks at the vulnerability of HDWs in the core area of Akure, Nigeria. The study area is made up of 11 residential quarters with 1149 buildings; 10% of buildings and five wells in each quarter were randomly selected for the study. Data were collected using structured questionnaires and laboratory examinations. Water quality assessment showed that most parameters fall within WHO permissible limits for drinking water. However, microbial examinations indicated that drinking water quality was compromised in two residential quarters as there was evidence of coliform and e-coli. The study also identified other possible sources of water contamination in the study area. This paper recommends regular treatment of wells and the adoption of pipe-borne water supply systems in the city and other similar cities in developing countries.     

Chemical water quality in Thailand and its impacts on the drinking water production in Thailand

In Thailand, surface water and groundwater are the main water sources for tap water and drinking water production. Thirty-six different samples from surface waters from Chao Praya and Mae Klong rivers, tap waters, bottled drinking waters, groundwaters and commercial ice cubes from around the Bangkok area were collected. Water samples were also taken from two waterworks in the Chonburi province. The extensive survey showed that, overall in all water samples investigated, there was only a minor pollution which could be traced back to the analyses performed including amongst others total organic carbon, inorganics and heavy metals, pesticides, organochlorine compounds, volatile organic compounds, surfactants, pharmaceuticals and disinfection by-products. However, whenever organic micropollutants could be detected in surface water, such as, e.g. the herbicide atrazine, they were also present in the tap water produced thereof proving that the present treatment steps are not sufficient for removal of such pollutants. The concentration of disinfection by-products was higher in tap water produced from Chao Praya river than from Mae Klong river. Disinfection by-products were also found in bottled drinking water. Commercial ice cubes contained anionic surfactants and their metabolites at elevated concentrations. The data of this study constitute the first set of homogenous data for the chemical water quality and also aid development of new water quality criteria in Thailand.     

Development and validation of a drinking water temperature model in domestic drinking water supply systems

Domestic drinking water supply systems (DDWSs) are the final step in the delivery of drinking water to consumers. Temperature is one of the rate-controlling parameters for many chemical and microbiological processes and is, therefore, considered as a surrogate parameter for water quality processes. In this study, a mathematical model is presented that predicts temperature dynamics of the drinking water in DDWSs. A full-scale DDWS resembling a conventional system was built and run according to one year of stochastic demands with a time step of 10 s. The drinking water temperature was measured at each point-of-use in the systems and the data-set was used for model validation. The temperature model adequately reproduced the temperature profiles, both in cold and hot water lines, in the full-scale DDWS. The model showed that inlet water temperature and ambient temperature have a large effect on the water temperature in the DDWSs.     

Setting action levels for drinking water: are we protecting our health or our economy (or our backs!)?

Clean and healthy drinking water is important for life. Drinking water can be drawn from streams, lakes and rivers, directly collected (and stored) from rain, acquired by desalination of ocean water and melting of ice or it can be extracted from groundwater resources. Groundwater may reach the earth's surface in the form of springs or can be extracted via dug or drilled wells; it also contributes significantly to river baseflow. Different water quality issues have to be faced when utilising these different water resources. Some of these are at present largely neglected in water quality regulations. This paper focuses on the inorganic chemical quality of natural groundwater. Possible health effects, the problems of setting meaningful action levels or maximum admissible concentrations (MAC-values) for drinking water, and potential shortcomings in current legislation are discussed. An approach to setting action levels based on transparency, toxicological risk assessment, completeness, and identifiable responsibility is suggested.     

Designing water supplies: Optimizing drinking water composition for maximum economic benefit

It is possible to optimize drinking water composition based on a valuation of the impacts of changed water quality. This paper introduces a method for assessing the potential for designing an optimum drinking water composition by the use of membrane desalination and remineralization. The method includes modeling of possible water quality blends and an evaluation of corrosion indices. Based on concentration-response relationships a range of impacts on public health, material lifetimes and consumption of soap have been valued for Perth, Western Australia and Copenhagen, Denmark. In addition to water quality aspects, costs of water production, fresh water abstraction and CO₂-emissions are integrated into a holistic economic assessment of the optimum share of desalinated water in water supplies. Results show that carefully designed desalination post-treatment can have net benefits up to €0.3 ± 0.2 per delivered m³ for Perth and €0.4(±0.2) for Copenhagen. Costs of remineralization and green house gas emission mitigation are minor when compared to the potential benefits of an optimum water composition. Finally, a set of optimum water quality criteria is proposed for the guidance of water supply planning and management.     

Genetically Safe Drinking Water. Requirements and Methods of Its Quality Control

The article contains a substantiation of a necessity of a new standard for assessment of the quality of genetically safe drinking water designed for consumption by man. Requirements to the quality of such water include 76 indices and are presented by 10 individual groups; extended is the number of indices of drinking waters of the level of toxicity (biotesting in 7 test objects), normative references to the methods of their control.     

Epidemoilogical Studies on cancer and organic compounds in U.S. drinking waters

Two national surveys of U. S. drinking waters have been conducted todetermine the presence and concentration levels of organic compounds, particularly trihalomethanes. Most drinking water supplies from surface water sources have been shown to contain numerous organic compounds at very low levels. Chloroform is present in virtually all drinking water supplies that are treated with chlorine as a disinfectant.The health effects of organic compounds have been investigated by animal and epidemiological studies.Numerous epidemiological studies have been conducted on various geographic sections of the United States. Fourteen epidemiological studies that were hypothesis generating studies were conducted to determine if there is a positive — association between drinking water and increased cancer mortality. These studies may indicate which organ(s) might potentially be the affected organ(s). Further epidemiological studies that tested various hypotheses were conducted A summary of these studies is presented, which indicates that there is potentially an increased risk of bladder, colon, and rectum cancer from drinking waters containing trihalomethanes.