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Sample records for drinking water disinfected

  1. [Drinking water decontamination with isolative sorbent disinfectants].

    PubMed

    Krasnov, M S

    2004-01-01

    Drinking water can be decontaminated with the use of isolative sorbent disinfectants. Consideration of the effectiveness of water disinfectants and the sorptive power of porous materials against bacteria and viruses attested to the favour of iodine and silver-containing disinfectants and their compositions on porous aggressive carriers to be employed in extreme conditions such as on board crewed space vehicles.

  2. ALTERNATIVE DISINFECTANTS FOR DRINKING WATER TREATMENT

    EPA Science Inventory

    During a one-year study at Jefferson Parish, Louisiana the chemical, microbiological, and mutagenic effects of using the major drinking water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. ests were performed on samples collected from various treatm...

  3. MUTAGENICITY OF DRINKING WATER FOLLOWING DISINFECTION

    EPA Science Inventory

    Many drinking water utilities in the USA are considering alternatives to chlorine for disinfection in order to comply with federal regulations regarding disinfection by-products. An evaluation is thus needed of the potential risks associated with the use of alternative disinfecta...

  4. DISINFECTION OF WATER: DRINKING WATER, RECREATIONAL WATER, AND WASTEWATER

    EPA Science Inventory

    This chapter describes and categorizes the methodology used for disinfection of drinking water, recreational water and wastewater including wastewater sludges. It largely is a literature summary and references articles covering the years of 1939 through 1999, with a few reference...

  5. DRINKING WATER DISINFECTION BY-PRODUCTS: WHAT IS KNOWN

    EPA Science Inventory

    Chlorine, ozone, chlorine dioxide, and chloramine are currently the major disinfectants being used to disinfect drinking water. Although the alternative disinfectants (ozone, chlorine dioxide, and chloramine) are increasing in popularity in the United States, chlorine is still us...

  6. Studies on Disinfection By-Products and Drinking Water

    USGS Publications Warehouse

    Rostad, Colleen E.

    2007-01-01

    Drinking water is disinfected with chemicals to remove pathogens, such as Giardia and Cryptosproridium, and prevent waterborne diseases such as cholera and typhoid. During disinfection, by-products are formed at trace concentrations. Because some of these by-products are suspected carcinogens, drinking water utilities must maintain the effectiveness of the disinfection process while minimizing the formation of by-products.

  7. Emergency Disinfection of Drinking Water

    MedlinePlus

    ... menu Learn the Issues Air Chemicals and Toxics Climate Change Emergencies Greener Living Health and Safety Land and Cleanup Pesticides Waste Water Science & Technology Air Climate Change Ecosystems Health Land, Waste and Cleanup Pesticides Substances ...

  8. Disinfection By-Products: Formation and Occurrence in Drinking Water

    EPA Science Inventory

    The disinfection of drinking water has been rightly hailed as a public health triumph of the twentieth century. Millions of people worldwide receive quality drinking water every day from their public water systems. However, chemical disinfection has also produced an unintended he...

  9. The Next Generation of Drinking Water Disinfection By-Products

    EPA Science Inventory

    The disinfection of drinking water has been rightly hailed as a public health triumph of the 20th century. Millions of people worldwide receive quality drinking water every day from their public water systems. However, chemical disinfection has also produced an unintended healt...

  10. Health effects of drinking water disinfectants and disinfection by-products

    SciTech Connect

    Condie, L.W.; Bercz, J.P.

    1986-01-01

    This paper summarizes toxicological studies conducted with drinking water disinfectants. Toxicological effects, which are associated with the disinfectants themselves as well as with the by-products formed when disinfectants react with organic material present in water, are considered. The health impact of chemical reactions occurring between residual disinfectants and nutrients in the gastrointestinal tract is also discussed. 40 references, 5 tables.

  11. MODELING DISINFECTANT RESIDUALS IN DRINKING-WATER STORAGE TANKS

    EPA Science Inventory

    The factors leading to the loss of disinfectant residual in well-mixed drinking-water storage tanks are studied. Equations relating disinfectant residual to the disinfectant's reation rate, the tank volume, and the fill and drain rates are presented. An analytical solution for ...

  12. Environmental health perspectives. Volume 46. Drinking water disinfectants - December 1982

    SciTech Connect

    Lucier, G.W.; Hook, G.E.R.

    1982-01-01

    Among subjects considered are chlorine dioxide, N-chloramines, mutagenic activity by disinfectant reaction products, trihalomethane and behavioral toxicity, and carcinogenic risk estimation. There are 27 papers on these and related topics. The volume stems from a symposium on drinking water disinfectants and disinfectant by-products.

  13. Impact of disinfection on drinking water biofilm bacterial community.

    PubMed

    Mi, Zilong; Dai, Yu; Xie, Shuguang; Chen, Chao; Zhang, Xiaojian

    2015-11-01

    Disinfectants are commonly applied to control the growth of microorganisms in drinking water distribution systems. However, the effect of disinfection on drinking water microbial community remains poorly understood. The present study investigated the impacts of different disinfectants (chlorine and chloramine) and dosages on biofilm bacterial community in bench-scale pipe section reactors. Illumina MiSeq sequencing illustrated that disinfection strategy could affect both bacterial diversity and community structure of drinking water biofilm. Proteobacteria tended to predominate in chloraminated drinking water biofilms, while Firmicutes in chlorinated and unchlorinated biofilms. The major proteobacterial groups were influenced by both disinfectant type and dosage. In addition, chloramination had a more profound impact on bacterial community than chlorination.

  14. Impact of disinfection on drinking water biofilm bacterial community.

    PubMed

    Mi, Zilong; Dai, Yu; Xie, Shuguang; Chen, Chao; Zhang, Xiaojian

    2015-11-01

    Disinfectants are commonly applied to control the growth of microorganisms in drinking water distribution systems. However, the effect of disinfection on drinking water microbial community remains poorly understood. The present study investigated the impacts of different disinfectants (chlorine and chloramine) and dosages on biofilm bacterial community in bench-scale pipe section reactors. Illumina MiSeq sequencing illustrated that disinfection strategy could affect both bacterial diversity and community structure of drinking water biofilm. Proteobacteria tended to predominate in chloraminated drinking water biofilms, while Firmicutes in chlorinated and unchlorinated biofilms. The major proteobacterial groups were influenced by both disinfectant type and dosage. In addition, chloramination had a more profound impact on bacterial community than chlorination. PMID:26574105

  15. Ultraviolet (UV) Disinfection for Drinking Water Systems

    EPA Science Inventory

    UV disinfection is an effective process for inactivating many microbial pathogens in water with potential to serve as stand-alone treatment or in combination with other disinfectants. USEPA provided guidance on the validation of UV reactors nearly a decade ago. Since then, lesson...

  16. [Research development on disinfection technology for viruses in drinking water].

    PubMed

    Zhang, Yun; Zhang, Qiang; Liu, Yan; Dai, Ruihua; Liu, Xiang

    2010-09-01

    With the deterioration of water source pollution, the quality requirements for drinking water of countries will become stricter and stricter, and the microbe index has been one of the important aspects. The introduction of the virus index and the development of disinfection technology focusing on virus have significant importance for the improvement of the drinking water standards and for the protection of people health in every country. To be familiar with the domestic and abroad research development of the disinfection control technology focusing on virus provides certain theory guidance and technological support for continuously improving drinking water standard in our country and for establishing safer drinking water processing technologies. So, this article will comprehensively describes 4 aspects: resistance comparison of virus over every disinfection technology, influential factors of disinfection, research development of new technology, and the mechanisms.

  17. ALTERNATIVE DISINFECTION FOR DRINKING WATER TREATMENT

    EPA Science Inventory

    During a one-yr study at Jefferson Parish, La., the chemical, microbiological, and mutagenic effects os using the major drinkgin water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. Tests were performed on samples collected from various treatment s...

  18. IDENTIFICATION OF TI02/UV DISINFECTION BYPRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Due to concern over the presence of trihalomethanes (THMs) and other chlorinated byproducts in chlorinated drinking water, alternative disinfection methods are being explored. One of the alternative treatment methods currently being evaluated for potential use with small systems ...

  19. Recent advances in drinking water disinfection: successes and challenges.

    PubMed

    Ngwenya, Nonhlanhla; Ncube, Esper J; Parsons, James

    2013-01-01

    Drinking water is the most important single source of human exposure to gastroenteric diseases, mainly as a result of the ingestion of microbial contaminated water. Waterborne microbial agents that pose a health risk to humans include enteropathogenic bacteria, viruses, and protozoa. Therefore, properly assessing whether these hazardous agents enter drinking water supplies, and if they do, whether they are disinfected adequately, are undoubtedly aspects critical to protecting public health. As new pathogens emerge, monitoring for relevant indicator microorganisms (e.g., process microbial indicators, fecal indicators, and index and model organisms) is crucial to ensuring drinking water safety. Another crucially important step to maintaining public health is implementing Water Safety Plans (WSPs), as is recommended by the current WHO Guidelines for Drinking Water Quality. Good WSPs include creating health-based targets that aim to reduce microbial risks and adverse health effects to which a population is exposed through drinking water. The use of disinfectants to inactivate microbial pathogens in drinking water has played a central role in reducing the incidence of waterborne diseases and is considered to be among the most successful interventions for preserving and promoting public health. Chlorine-based disinfectants are the most commonly used disinfectants and are cheap and easy to use. Free chlorine is an effective disinfectant for bacteria and viruses; however, it is not always effective against C. parvum and G. lamblia. Another limitation of using chlorination is that it produces disinfection by-products (DBPs), which pose potential health risks of their own. Currently, most drinking water regulations aggressively address DBP problems in public water distribution systems. The DBPs of most concern include the trihalomethanes (THMs), the haloacetic acids (HAAs), bromate, and chlorite. However, in the latest edition of the WHO Guidelines for Drinking Water Quality

  20. Recent advances in drinking water disinfection: successes and challenges.

    PubMed

    Ngwenya, Nonhlanhla; Ncube, Esper J; Parsons, James

    2013-01-01

    Drinking water is the most important single source of human exposure to gastroenteric diseases, mainly as a result of the ingestion of microbial contaminated water. Waterborne microbial agents that pose a health risk to humans include enteropathogenic bacteria, viruses, and protozoa. Therefore, properly assessing whether these hazardous agents enter drinking water supplies, and if they do, whether they are disinfected adequately, are undoubtedly aspects critical to protecting public health. As new pathogens emerge, monitoring for relevant indicator microorganisms (e.g., process microbial indicators, fecal indicators, and index and model organisms) is crucial to ensuring drinking water safety. Another crucially important step to maintaining public health is implementing Water Safety Plans (WSPs), as is recommended by the current WHO Guidelines for Drinking Water Quality. Good WSPs include creating health-based targets that aim to reduce microbial risks and adverse health effects to which a population is exposed through drinking water. The use of disinfectants to inactivate microbial pathogens in drinking water has played a central role in reducing the incidence of waterborne diseases and is considered to be among the most successful interventions for preserving and promoting public health. Chlorine-based disinfectants are the most commonly used disinfectants and are cheap and easy to use. Free chlorine is an effective disinfectant for bacteria and viruses; however, it is not always effective against C. parvum and G. lamblia. Another limitation of using chlorination is that it produces disinfection by-products (DBPs), which pose potential health risks of their own. Currently, most drinking water regulations aggressively address DBP problems in public water distribution systems. The DBPs of most concern include the trihalomethanes (THMs), the haloacetic acids (HAAs), bromate, and chlorite. However, in the latest edition of the WHO Guidelines for Drinking Water Quality

  1. Guidelines for ultraviolet disinfection of drinking water: considerations for Ontario.

    PubMed

    Hofmann, Ron; Andrews, Bob; Lachmaniuk, Pat

    The Ontario Ministry of the Environment is actively investigating protocols for approving the installation of ultraviolet (UV) disinfection systems for drinking water disinfection. This paper discusses issues that may be considered for selecting the appropriate UV dose, validating UV reactor performance, and monitoring the performance of the reactor once installed.

  2. Disinfection By-Products and Drinking Water Treatment

    EPA Science Inventory

    The disinfection of drinking water has been rightly hailed as a public health triumph of the 20th century. Before its widespread use, millions of people died from waterborne diseases. Now, people in developed nations receive quality drinking water every day from their public wa...

  3. An evaluation of drinking water samples treated with alternative disinfectants

    SciTech Connect

    Patterson, K.S.; Lykins, B.W. Jr.; Garner, L.M.

    1995-10-01

    Due to concern over potential human health risks associated with the use of chlorine (Cl{sub 2}) for disinfection of drinking water, many utilities are considering alternative disinfectants. An evaluation is thus needed of the potential risks associated with the use of alternative disinfectants relative to those posed by Cl{sub 2}. At a pilot-scale drinking water plant in Jefferson Parish, LA., two studies were conducted in which clarified and sand filtered Mississippi River water was treated with either ozone (O{sub 3}), monochloramine (NH{sub 2}Cl), Cl{sub 2} or was not disinfected. Ozonated water was also post-disinfected with either NH{sub 2}Cl or Cl{sub 2}, to provide a disinfectant residual. For each treatment stream total organic carbon (TOC), total organic halide (TOX) and microbiological contaminants were determined. XAD resin concentrates were also prepared for mutagenicity testing in the Ames Salmonella assay. Water samples disinfected with O{sub 3} alone had low levels of mutagenic activity, the same as the non-disinfected water. The level of mutagenicity observed following chlorination was approximately twice that observed following treatment with NH{sub 2}Cl. Disinfection with O{sub 3} prior to treatment with either Cl{sub 2} or NH{sub 2}Cl resulted in a significantly lower level of mutagenicity than when either disinfectant was used alone. The concentrations of TOX present in the water samples showed a pattern similar to that of the mutagenicity data. The levels of TOC, by contrast, were similar for all the treatment streams. No significant baterial contamination was observed in water samples treated with either Cl{sub 2} or NH{sub 2}Cl alone or in combination with O{sub 3}, as determined by heterotrophic plate counts. However, O{sub 3} alone did not insure an acceptable level of disinfection at the end of the treatment stream.

  4. The Occurrence and Comparative Toxicity of Haloacetaldehyde Disinfection Byproducts in Drinking Water

    EPA Science Inventory

    The introduction of drinking water disinfection greatly reduced the incidence of waterborne diseases. However, the reaction between disinfectants and natural organic matter in the source water can lead to an unintended consequence, which is the formation of drinking water disinfe...

  5. CHEMICAL AND BIOLOGICAL CHARACTERIZATION OF NEWLY DISCOVERED IODOACID DRINKING WATER DISINFECTION BYPRODUCTS

    EPA Science Inventory

    Iodoacid drinking water disinfection byproducts (DBPs) were recently uncovered in drinking water samples from source water with a high bromide/iodide concentration that was disinfected with chloramines. The purpose of this paper is to report the analytical chemical identification...

  6. Roadmap for Interdisciplinary Research on Drinking Water Disinfection By-Products

    EPA Science Inventory

    Slide presentation on interdisciplinary research on drinking water disinfection by-products which summarized important issues with drinking water disinfection by-products and focused on emerging, unregulated DBPs.

  7. COMPARATIVE RISK DILEMNAS IN DRINKING WATER DISINFECTION [EDITORIAL

    EPA Science Inventory

    Disinfection of drinking water supplies has been one of the most succesful public health interventions of the twentieth century. It has virtually eliminated outbreaks of serious waterborne infectious diseases, such as cholera and typhoid. there are still, however, an average of...

  8. DRINKING WATER DISINFECTION BYPRODUCTS AND DURATION OF GESTATION

    EPA Science Inventory

    Recent studies of drinking water disinfection by-products (DBPs) suggest high exposure decreases risk of preterm birth. We examined this association with total trihalomethane (TTHM) and five haloacetic acids (HAA5) among 2,041 women in a prospective pregnancy study conducted from...

  9. Drinking water and biofilm disinfection by Fenton-like reaction.

    PubMed

    Gosselin, F; Madeira, L M; Juhna, T; Block, J C

    2013-10-01

    A Fenton-like disinfection process was conducted with Fenton's reagent (H2O2) at pH 3 or 5 on autochthonous drinking water biofilms grown on corroded or non-corroded pipe material. The biofilm disinfection by Fenton-like oxidation was limited by the low content of iron and copper in the biomass grown on non-corroded plumbing. It was slightly improved by spiking the distribution system with some additional iron source (soluble iron II or ferrihydrite particles appeared as interesting candidates). However successful in situ disinfection of biofilms was only achieved in fully corroded cast iron pipes using H2O2 and adjusting the pH to 5. These new results provide additional support for the use of Fenton's processes for cleaning drinking water distribution systems contaminated with biological agents or organics.

  10. Formation of disinfection byproducts in typical Chinese drinking water.

    PubMed

    Liu, Wenbo; Zhao, Yanmei; Chow, Christopher W K; Wang, Dongsheng

    2011-01-01

    Eight typical drinking water supplies in China were selected in this study. Both source and tap water were used to investigate the occurrence of chlorinated disinfection byproducts (DBPs), and seasonal variation in the concentrations of trihalomethanes (THMs) of seven water sources was compared. The results showed that the pollution level for source water in China, as shown by DBP formation potential, was low. The most encountered DBPs were chloroform, dichloroacetic acid, trichloroacetic acid, and chlorodibromoacetic acid. The concentration of every THMs and haloacetic acid (HAA) compound was under the limit of standards for drinking water quality. The highest total THMs concentrations were detected in spring.

  11. Drinking water disinfection byproducts: review and approach to toxicity evaluation.

    PubMed Central

    Boorman, G A

    1999-01-01

    There is widespread potential for human exposure to disinfection byproducts (DBPs) in drinking water because everyone drinks, bathes, cooks, and cleans with water. The need for clean and safe water led the U.S. Congress to pass the Safe Drinking Water Act more than 20 years ago in 1974. In 1976, chloroform, a trihalomethane (THM) and a principal DBP, was shown to be carcinogenic in rodents. This prompted the U.S. Environmental Protection Agency (U.S. EPA) in 1979 to develop a drinking water rule that would provide guidance on the levels of THMs allowed in drinking water. Further concern was raised by epidemiology studies suggesting a weak association between the consumption of chlorinated drinking water and the occurrence of bladder, colon, and rectal cancer. In 1992 the U.S. EPA initiated a negotiated rulemaking to evaluate the need for additional controls for microbial pathogens and DBPs. The goal was to develop an approach that would reduce the level of exposure from disinfectants and DBPs without undermining the control of microbial pathogens. The product of these deliberations was a proposed stage 1 DBP rule. It was agreed that additional information was necessary on how to optimize the use of disinfectants while maintaining control of pathogens before further controls to reduce exposure beyond stage 1 were warranted. In response to this need, the U.S. EPA developed a 5-year research plan to support the development of the longer term rules to control microbial pathogens and DBPs. A considerable body of toxicologic data has been developed on DBPs that occur in the drinking water, but the main emphasis has been on THMs. Given the complexity of the problem and the need for additional data to support the drinking water DBP rules, the U.S. EPA, the National Institute of Environmental Health Sciences, and the U.S. Army are working together to develop a comprehensive biologic and mechanistic DBP database. Selected DBPs will be tested using 2-year toxicity and

  12. Drinking water disinfection byproducts: review and approach to toxicity evaluation.

    PubMed

    Boorman, G A

    1999-02-01

    There is widespread potential for human exposure to disinfection byproducts (DBPs) in drinking water because everyone drinks, bathes, cooks, and cleans with water. The need for clean and safe water led the U.S. Congress to pass the Safe Drinking Water Act more than 20 years ago in 1974. In 1976, chloroform, a trihalomethane (THM) and a principal DBP, was shown to be carcinogenic in rodents. This prompted the U.S. Environmental Protection Agency (U.S. EPA) in 1979 to develop a drinking water rule that would provide guidance on the levels of THMs allowed in drinking water. Further concern was raised by epidemiology studies suggesting a weak association between the consumption of chlorinated drinking water and the occurrence of bladder, colon, and rectal cancer. In 1992 the U.S. EPA initiated a negotiated rulemaking to evaluate the need for additional controls for microbial pathogens and DBPs. The goal was to develop an approach that would reduce the level of exposure from disinfectants and DBPs without undermining the control of microbial pathogens. The product of these deliberations was a proposed stage 1 DBP rule. It was agreed that additional information was necessary on how to optimize the use of disinfectants while maintaining control of pathogens before further controls to reduce exposure beyond stage 1 were warranted. In response to this need, the U.S. EPA developed a 5-year research plan to support the development of the longer term rules to control microbial pathogens and DBPs. A considerable body of toxicologic data has been developed on DBPs that occur in the drinking water, but the main emphasis has been on THMs. Given the complexity of the problem and the need for additional data to support the drinking water DBP rules, the U.S. EPA, the National Institute of Environmental Health Sciences, and the U.S. Army are working together to develop a comprehensive biologic and mechanistic DBP database. Selected DBPs will be tested using 2-year toxicity and

  13. MUTAGENICITY AND DISINFECTION BY-PRODUCTS IN SURFACE DRINKING WATER DISINFECTED WITH PERACETIC ACID

    EPA Science Inventory

    The aims of this research were to study the influence of peracetic acid (PAA) on the formation of mutagens in surface waters used for human consumption and to assess its potential application for the disinfection of drinking water. The results obtained using PAA were compared to ...

  14. Drinking water and health: Disinfectants and disinfectant by-products. Volume 7

    SciTech Connect

    Not Available

    1987-01-01

    Studies of the toxicity of the by-products of disinfectants have focused on the trihalomethanes (THMs), which are formed during chlorination and for which considerable data on carcinogenicity have been developed. The level of total THMs in finished drinking water, currently regulated at 100 micrograms/L, should be reduced. Noting that chloroform is the principal THM produced by chlorination, the subcommittee found this level to be unsupportable on the basis of the risk values for chloroform developed in this review. Other, non-volatile by-products of chlorination may be important in contributing mutagenic properties to drinking water, especially when the natural water being treated contains high levels of organic matter. Short-term animal skin tests, although not conclusive, provide indications that organic concentrates from chlorinated water are tumorigenic under some experimental conditions. Unfortunately, many by-products of chlorination and other disinfection practices have not been identified. Consequently, the risks of ingesting cannot be quantified at present, but are potentially high enough to warrant continued efforts to analyze them. The use of alternative methods of drinking water disinfection is increasing, largely due to health and regulatory concerns about trihalomethanes. Thus, the nature and toxicity of the by-products of some other widely used water treatments (chloramination, ozonation, and chlorine dioxide) are also evaluated in the report to the extent allowed by available data. The subcommittee calculated quantitative risk assessment for disinfectants or their by-products when there was sufficient data.

  15. RESEARCH PLAN FOR MICROBIAL PATHOGENS AND DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    This research plan was developed to describe research needed to support EPA's development of drinking water regulations concerning disinfectants, disinfection by-products (DBPs) and microbial pathogens, focusing on key scientific and technical information needed. The research pl...

  16. Differential resistance of drinking water bacterial populations to monochloramine disinfection.

    PubMed

    Chiao, Tzu-Hsin; Clancy, Tara M; Pinto, Ameet; Xi, Chuanwu; Raskin, Lutgarde

    2014-04-01

    The impact of monochloramine disinfection on the complex bacterial community structure in drinking water systems was investigated using culture-dependent and culture-independent methods. Changes in viable bacterial diversity were monitored using culture-independent methods that distinguish between live and dead cells based on membrane integrity, providing a highly conservative measure of viability. Samples were collected from lab-scale and full-scale drinking water filters exposed to monochloramine for a range of contact times. Culture-independent detection of live cells was based on propidium monoazide (PMA) treatment to selectively remove DNA from membrane-compromised cells. Quantitative PCR (qPCR) and pyrosequencing of 16S rRNA genes was used to quantify the DNA of live bacteria and characterize the bacterial communities, respectively. The inactivation rate determined by the culture-independent PMA-qPCR method (1.5-log removal at 664 mg·min/L) was lower than the inactivation rate measured by the culture-based methods (4-log removal at 66 mg·min/L). Moreover, drastic changes in the live bacterial community structure were detected during monochloramine disinfection using PMA-pyrosequencing, while the community structure appeared to remain stable when pyrosequencing was performed on samples that were not subject to PMA treatment. Genera that increased in relative abundance during monochloramine treatment include Legionella, Escherichia, and Geobacter in the lab-scale system and Mycobacterium, Sphingomonas, and Coxiella in the full-scale system. These results demonstrate that bacterial populations in drinking water exhibit differential resistance to monochloramine, and that the disinfection process selects for resistant bacterial populations.

  17. ANALYZING DRINKING WATER FOR DISINFECTION BYPRODUCTS

    EPA Science Inventory

    In the mid 19th Century, Chinese workers on the North American transcontinental railroad suffered less illness than other groups. While generally mysterious at the time, today the reason is obvious. The Chinese preference for tea required heating the water, thus killing many path...

  18. Energy-efficient drinking water disinfection for greenhouse gas mitigation

    SciTech Connect

    Gadgil, A.J.; Greene, D.M.; Rosenfeld, A.

    1998-07-01

    Anecdotal evidence suggests that approximately one billion people worldwide use cookstoves to boil their drinking water. About half of this population is in China. Some populations (e.g. Jakarta) spend 1% of their GDP on boiling drinking water. Impoverished and/or ignorant populations not yet boiling their drinking water will do so when they can both afford it and understand the risks of unsafe drinking water. A recently developed water disinfection technology (UV Waterworks) can produce safe drinking water while earning tradable carbon credits (or credit as a clean development mechanism) when implemented as part of national energy, health, and carbon emissions trading policy, UV Waterworks uses approximately 6,000 times less energy than boiling over a biomass cookstove. Each unit that replaces boiling may save up to 175 or 300 tons/year of carbon-equivalent GHG emissions, depending on if it replaces sustainably harvested biomass (SHB) or non-SHB. For the approximately 500M Chinese boiling their drinking water over biomass (assumed SHB), this suggests a technical potential (that is, potential under the limiting case of 100% market adoption) of saving 87M tons/year of carbon-equivalent non-CO{sub 2} GHG emissions. The energy savings and corresponding emissions reductions will vary with cookstove fuels and stove efficiency: non-SHB and kerosene represent the most and least GHG-producing cookstove fuels, respectively, among those readily available to the populations of interest. The authors bracket the global technical potential for carbon emission reductions resulting from implementation of UV Waterworks, and estimate the value of tradable carbon credits earned from these reductions.

  19. Controlling Legionella in hospital drinking water: an evidence-based review of disinfection methods.

    PubMed

    Lin, Yusen E; Stout, Janet E; Yu, Victor L

    2011-02-01

    Hospital-acquired Legionnaires' disease is directly linked to the presence of Legionella in hospital drinking water. Disinfecting the drinking water system is an effective preventive measure. The efficacy of any disinfection measures should be validated in a stepwise fashion from laboratory assessment to a controlled multiple-hospital evaluation over a prolonged period of time. In this review, we evaluate systemic disinfection methods (copper-silver ionization, chlorine dioxide, monochloramine, ultraviolet light, and hyperchlorination), a focal disinfection method (point-of-use filtration), and short-term disinfection methods in outbreak situations (superheat-and-flush with or without hyperchlorination). The infection control practitioner should take the lead in selection of the disinfection system and the vendor. Formal appraisals by other hospitals with experience of the system under consideration is indicated. Routine performance of surveillance cultures of drinking water to detect Legionella and monitoring of disinfectant concentrations are necessary to ensure long-term efficacy.

  20. Field-testing UV disinfection of drinking water

    SciTech Connect

    Gadgil, A.; Drescher, A.; Greene, D.; Miller, P.; Motau, C.; Stevens, F.

    1997-09-01

    A recently invented device, ``UV Waterworks,`` uses ultraviolet (UV) light to disinfect drinking water. Its novel features are: low cost, robust design, rapid disinfection, low electricity use, low maintenance, high flow rate and ability to work with unpressurized water sources. The device could service a community of 1,000 persons, at an annual total cost of less than 10 US cents per person. UV Waterworks has been successfully tested in the laboratory. Limited field trials of an early version of the device were conducted in India in 1994--95. Insights from these trials led to the present design. Extended field trials of UV Waterworks, initiated in South Africa in February 1997, will be coordinated by the South African Center for Essential Community Services (SACECS), with technical and organizational support from Lawrence Berkeley National Laboratory(LBNL) and the Natural Resources Defense Council (both US). The first of the eight planned sites of the year long trial is an AIDS hospice near Durban. Durban metro Water and LBNL lab-tested a UV Waterworks unit prior to installing it at the hospice in August, 1997. The authors describe the field test plans and preliminary results from Durban.

  1. GC/MS IDENTIFICATION OF DRINKING WATER DISINFECTION BY-PRODUCTS FROM MILWAUKEE'S NEW OZONATION PLANTS

    EPA Science Inventory

    The Milwaukee Water Works recently added ozonation disinfection facilities to their municipal drinking water treatment. Coupling ozone treatment with biologically active filtration (BAF) was seen as a logical step to enhance multiple water quality objectives (an effective barrier...

  2. [First results on the use of chloramines to reduce disinfection byproducts in drinking water].

    PubMed

    Azara, Antonio; Muresu, Elena; Dettori, Marco; Ciappeddu, Pierluigi; Deidda, Antonio; Maida, Alessandro

    2010-01-01

    The presence of disinfection byproducts (DBP) in drinking water raises concerns about the safety of chlorination and is one of the problems inherent the use of surface water as a source of drinking water. In order to reduce the presence of DBP (in particular of chlorites), we evaluated the combined use of chlorine dioxide for primary disinfection and monochloramine for residual disinfection in a water purification plant and distribution system in Sardinia (Italy). The results are very encouraging. Disinfection byproducts were reduced and other parameters were found to be within the recommended standards, indicating further improvements of the purification process.

  3. Metagenomic analyses of drinking water receiving different disinfection treatments.

    PubMed

    Gomez-Alvarez, Vicente; Revetta, Randy P; Santo Domingo, Jorge W

    2012-09-01

    A metagenome-based approach was used to assess the taxonomic affiliation and function potential of microbial populations in free-chlorine-treated (CHL) and monochloramine-treated (CHM) drinking water (DW). In all, 362,640 (averaging 544 bp) and 155,593 (averaging 554 bp) pyrosequencing reads were analyzed for the CHL and CHM samples, respectively. Most annotated proteins were found to be of bacterial origin, although eukaryotic, archaeal, and viral proteins were also identified. Differences in community structure and function were noted. Most notably, Legionella-like genes were more abundant in the CHL samples while mycobacterial genes were more abundant in CHM samples. Genes associated with multiple disinfectant mechanisms were identified in both communities. Moreover, sequences linked to virulence factors, such as antibiotic resistance mechanisms, were observed in both microbial communities. This study provides new insights into the genetic network and potential biological processes associated with the molecular microbial ecology of DW microbial communities.

  4. Disinfectant Penetration into Nitrifying Drinking Water Distribution System Biofilm Using Microelectrodes

    EPA Science Inventory

    Nitrification within drinking water distribution systems reduces water quality, causes difficulties maintaining adequate disinfectant residual, and poses public health concerns including exposure to nitrite, nitrate, and opportunistic pathogenic microorganisms. Monochloramine is...

  5. DETERMINATION OF NEWLY IDENTIFIED DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    The Metropolitan Water District of Southern California (MWDSC) is investigating the occurrence of 39 newly identified disinfection by-products (DBPs)-which were not included in the Information Collection Rule (ICR)-in drinking waters. Halomethanes (HMs), haloacetonitriles (HANs),...

  6. Association between drinking water disinfection and somatic parameters at birth.

    PubMed

    Kanitz, S; Franco, Y; Patrone, V; Caltabellotta, M; Raffo, E; Riggi, C; Timitilli, D; Ravera, G

    1996-05-01

    We conducted an epidemiological study in Liguria, Italy, on the association between somatic parameters at birth and drinking water disinfection with chlorine dioxide and/or sodium hypochlorite. Over 2 years (1988-1989), 676 births at two public hospitals, one in Genoa (548 cases) and another in Chiavari (128 cases) were examined and data regarding both mother and child were obtained from hospital records. Results indicate a higher frequency of small body length (< or = 49.5 cm) and small cranial circumference (< or = 35 cm) in infants born to mothers who drank water treated with chlorine compounds. In particular, the statistical analysis (by simultaneous variance analysis and Scheffé test) indicated that there may be an association between infants with smaller body length and mothers who drank water treated with chlorine dioxide [adjusted odds radio (OR) = 2.0; 95% CI = 1.2-3.3] or sodium hypoclorite (adjusted OR = 2.3; 95% CI = 1.3-4.2) and between infants with smaller cranial circumference and mothers who drank water treated with chlorine dioxide (adjusted OR = 2.2; 95% CI = 1.4-3.9) or sodium hypochlorite (adjusted OR = 3.5; 95% CI = 2.1-8.5). The presence of neonatal jaundice is almost twice as likely (adjusted OR = 1.7; 95% CI = 1.1-3.1) in infants whose mothers drank water treated with chlorine dioxide.

  7. Association between drinking water disinfection and somatic parameters at birth.

    PubMed

    Kanitz, S; Franco, Y; Patrone, V; Caltabellotta, M; Raffo, E; Riggi, C; Timitilli, D; Ravera, G

    1996-05-01

    We conducted an epidemiological study in Liguria, Italy, on the association between somatic parameters at birth and drinking water disinfection with chlorine dioxide and/or sodium hypochlorite. Over 2 years (1988-1989), 676 births at two public hospitals, one in Genoa (548 cases) and another in Chiavari (128 cases) were examined and data regarding both mother and child were obtained from hospital records. Results indicate a higher frequency of small body length (< or = 49.5 cm) and small cranial circumference (< or = 35 cm) in infants born to mothers who drank water treated with chlorine compounds. In particular, the statistical analysis (by simultaneous variance analysis and Scheffé test) indicated that there may be an association between infants with smaller body length and mothers who drank water treated with chlorine dioxide [adjusted odds radio (OR) = 2.0; 95% CI = 1.2-3.3] or sodium hypoclorite (adjusted OR = 2.3; 95% CI = 1.3-4.2) and between infants with smaller cranial circumference and mothers who drank water treated with chlorine dioxide (adjusted OR = 2.2; 95% CI = 1.4-3.9) or sodium hypochlorite (adjusted OR = 3.5; 95% CI = 2.1-8.5). The presence of neonatal jaundice is almost twice as likely (adjusted OR = 1.7; 95% CI = 1.1-3.1) in infants whose mothers drank water treated with chlorine dioxide. PMID:8743439

  8. EVALUATION OF ON-SITE CHLORINE GENERATORS FOR THE DISINFECTION OF DRINKING WATER

    EPA Science Inventory

    Public Water Systems (PWSs) routinely use various forms of chlorine as the disinfectant of choice for the treatment of drinking water. Chlorine is a popular choice because it is a very effective disinfectant, it is inexpensive, and it is widely available in various forms to suit...

  9. IDENTIFICATION OF NEW DRINKING WATER DISINFECTION BY-PRODUCTS FROM OZONE, CHLORINE DIOXIDE, CHLORAMINE, AND CHLORINE

    EPA Science Inventory

    Due to concern over the potential adverse health effects of trihalomethanes (THMs) and other chlorinated by-products in chlorinated drinking water, alternative disinfection methods are being explored. Ozone, chlorine dioxide, and chloramine are currently popular alternatives to ...

  10. MUTAGENICITY IN SALMONELLA OF HALONITROMETHANES: A RECENTLY RECOGNIZED CLASS OF DISINFECTION BYPRODUCTS IN DRINKING WATERS.

    EPA Science Inventory

    Halonitromethanes(HNMs)are a recently identified class of disinfection by-products (DBPs) in drinking water.They include chloronitromethane (CHN), dichloronitromethane (DCNM), trichloronitromethane (TCNM), bromonitromethane (BNM), dibromonitromethane (DBNM), tribromonitromethane ...

  11. DISINFECTION BY-PRODUCTS AND OTHER EMERGING CONTAMINANTS IN DRINKING WATER

    EPA Science Inventory

    Although drinking water disinfection by-products (DBPs) have been studied for the last 30 years, significant, new concerns have arisen. These concerns include adverse reproductive and developmental effects recently observed in human populations, concerns that the types of cancer...

  12. Why Do People Stop Treating Contaminated Drinking Water with Solar Water Disinfection (SODIS)?

    ERIC Educational Resources Information Center

    Tamas, Andrea; Mosler, Hans-Joachim

    2011-01-01

    Solar Water Disinfection (SODIS) is a simple method designed to treat microbiologically contaminated drinking water at household level. This article characterizes relapse behavior in comparison with continued SODIS use after a 7-month nonpromotion period. In addition, different subtypes among relapsers and continuers were assumed to diverge mainly…

  13. QSPR for predicting chloroform formation in drinking water disinfection.

    PubMed

    Luilo, G B; Cabaniss, S E

    2011-01-01

    Chlorination is the most widely used technique for water disinfection, but may lead to the formation of chloroform (trichloromethane; TCM) and other by-products. This article reports the first quantitative structure-property relationship (QSPR) for predicting the formation of TCM in chlorinated drinking water. Model compounds (n = 117) drawn from 10 literature sources were divided into training data (n = 90, analysed by five-way leave-many-out internal cross-validation) and external validation data (n = 27). QSPR internal cross-validation had Q² = 0.94 and root mean square error (RMSE) of 0.09 moles TCM per mole compound, consistent with external validation Q2 of 0.94 and RMSE of 0.08 moles TCM per mole compound, and met criteria for high predictive power and robustness. In contrast, log TCM QSPR performed poorly and did not meet the criteria for predictive power. The QSPR predictions were consistent with experimental values for TCM formation from tannic acid and for model fulvic acid structures. The descriptors used are consistent with a relatively small number of important TCM precursor structures based upon 1,3-dicarbonyls or 1,3-diphenols.

  14. Mammalian Cell Cytotoxicity and Genotoxicity of the Haloacetic Acids, A Major Class of Drinking Water Disinfection By-Products

    EPA Science Inventory

    The haloacetic acids (HAAs) are disinfection by-products (DBPs) that are formed during the disinfection of drinking water, wastewaters and recreational pool waters. Currently, five HAAs [bromoacetic acid (BAA), dibromoacetic acid (DBAA), chloroacetic acid (CAA), dichloroacetic ac...

  15. Occurrence assessment for disinfectants and disinfection by-products (phase 6A) in public drinking water. Final report

    SciTech Connect

    Not Available

    1992-08-03

    The EPA Office of Ground Water and Drinking Water is developing national primary drinking water regulations for disinfectant and disinfection by-product contaminants. Thirteen contaminants are being considered to be regulated under Phase 6. These contaminants, referred to as Phase 6a, are the subject of the report. The information is important for setting the Maximum Contaminant Level Goal for a contaminant. The exposure information also is used to estimate the baseline health impact assessment of current levels and for evaluation of the health benefits of the regulatory alternatives.

  16. Bench-Scale Evaluation of Peracetic Acid and Twin Oxide ™ as Disinfectants in Drinking Water

    EPA Science Inventory

    Chlorine is widely used as an inexpensive and potent disinfectant in the United States for drinking water. However, chlorine has the potential for forming carcinogenic and mutagenic disinfection by-products (DBPs). In this study, bench scale experiments were conducted at the U.S...

  17. Continuous-flow solar UVB disinfection reactor for drinking water.

    PubMed

    Mbonimpa, Eric Gentil; Vadheim, Bryan; Blatchley, Ernest R

    2012-05-01

    Access to safe, reliable sources of drinking water is a long-standing problem among people in developing countries. Sustainable solutions to these problems often involve point-of-use or community-scale water treatment systems that rely on locally-available resources and expertise. This philosophy was used in the development of a continuous-flow, solar UVB disinfection system. Numerical modeling of solar UVB spectral irradiance was used to define temporal variations in spectral irradiance at several geographically-distinct locations. The results of these simulations indicated that a solar UVB system would benefit from incorporation of a device to amplify ambient UVB fluence rate. A compound parabolic collector (CPC) was selected for this purpose. Design of the CPC was based on numerical simulations that accounted for the shape of the collector and reflectance. Based on these simulations, a prototype CPC was constructed using materials that would be available and inexpensive in many developing countries. A UVB-transparent pipe was positioned in the focal area of the CPC; water was pumped through the pipe to allow exposure of waterborne microbes to germicidal solar UVB radiation. The system was demonstrated to be effective for inactivation of Escherichia coli, and DNA-weighted UV dose was shown to govern reactor performance. The design of the reactor is expected to scale linearly, and improvements in process performance (relative to results from the prototype) can be expected by use of larger CPC geometry, inclusion of better reflective materials, and application in areas with greater ambient solar UV spectral irradiance than the location of the prototype tests. The system is expected to have application for water treatment among communities in (developing) countries in near-equatorial and tropical locations. It may also have application for disaster relief or military field operations, as well as in water treatment in areas of developed countries that receive

  18. Mass Spectrometry Identification of Toxicologically Important Drinking Water Disinfection By-Products

    EPA Science Inventory

    The disinfection of drinking water has been rightly hailed as a public health triumph of the 20th century. Before its widespread use, millions of people died from waterborne diseases. Now, people in developed nations receive quality drinking water every day from their public wate...

  19. Evaluation of Disinfection Byproducts Formed from the Chlorination of Lyophilized and Reconstituted NOM Concentrate from a Drinking Water Source - Poster

    EPA Science Inventory

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by difficulties in shipping large water quantities and NOM geographical and temporal variability. Access to a drinking water representative, shelf-stable, concentrated NOM source would solve th...

  20. Evaluation of Disinfection Byproducts formed from the Chlorination of Lyophilized and Reconstituted NOM Concentrate from a Drinking Water Source

    EPA Science Inventory

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by difficulties in shipping large water quantities and NOM geographical and temporal variability. Access to a drinking water representative, shelf-stable, concentrated NOM source would solve th...

  1. OCCURRENCE, GENOTOXICITY, AND CARCINOGENICITY OF EMERGING DISINFECTION BY-PRODUCTS IN DRINKING WATER: A REVIEW AND ROADMAP FOR RESEARCH

    EPA Science Inventory

    Disinfection by-products (DBPs) are formed when disinfectants (chlorine, ozone, chlorine dioxide, or chloramines) react with naturally occurring organic matter, anthropogenic contaminants, bromide, and iodide during the production of drinking water. Here we review 30 years of re...

  2. Toxic impact of bromide and iodide on drinking water disinfected with chlorine or chloramines.

    PubMed

    Yang, Yang; Komaki, Yukako; Kimura, Susana Y; Hu, Hong-Ying; Wagner, Elizabeth D; Mariñas, Benito J; Plewa, Michael J

    2014-10-21

    Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the most toxic. The objectives of this research were (1) to determine if monochloramine (NH2Cl) disinfection generated drinking water with less toxicity than water disinfected with free chlorine (HOCl) and (2) to determine the impact of added bromide and iodide in conjunction with HOCl or NH2Cl disinfection on mammalian cell cytotoxicity and genomic DNA damage induction. Water disinfected with chlorine was less cytotoxic but more genotoxic than water disinfected with chloramine. For both disinfectants, the addition of Br(-) and I(-) increased cytotoxicity and genotoxicity with a greater response observed with NH2Cl disinfection. Both cytotoxicity and genotoxicity were highly correlated with TOBr and TOI. However, toxicity was weakly and inversely correlated with TOCl. Thus, the forcing agents for cytotoxicity and genotoxicity were the generation of brominated and iodinated DBPs rather than the formation of chlorinated DBPs. Disinfection practices need careful consideration especially when using source waters containing elevated bromide and iodide.

  3. Effects of phosphorus on biofilm disinfections in model drinking water distribution systems.

    PubMed

    Fang, Wei; Hu, Jiangyong; Ong, Say Leong

    2010-09-01

    Drinking water biofilm development is affected by the available nutrient levels and the presence of disinfectants. Phosphorus is recognized as another important limiting nutrient besides organic carbon. In this study, drinking water biofilms were developed in annular reactors to examine the effects of phosphorus on the biofilm disinfections with free chlorine and monochloramine. Phosphorus addition was found to increase the biofilm cell number but decrease the exopolysaccharides (EPS) production. The disinfection efficacies of both free chlorine and monochloramine were increased when phosphorus was added into the reactor systems. At the same disinfection dosages, monochloramine showed greater biofilm removal efficiency than free chlorine. Monochloramine could be a better choice than free chlorine in biofilm disinfection when phosphate-based corrosion inhibitors are applied.

  4. DISINFECTION BYPRODUCTS IN DRINKING WATER [LETTER TO THE EDITOR

    EPA Science Inventory

    Comment on Professor Howard Weinberg's report on the analysis of potable water for disinfection byproducts.

    "I am unconvinced that it is necessary to identify and quantify each individual compound. Suppose we identify 1000 or 10,000 individual compounds, can we afford t...

  5. [Genotoxicity of drinking water during chlorine and chloramine disinfection and the influence of disinfection conditions using the umu-test].

    PubMed

    Liu, Qing; Zhang, Li-Ping; Liu, Wen-Jun; Nie, Xue-Biao; Zhang, Su-Xia; Zhang, Shun

    2010-01-01

    In this study, the effects of disinfectant dosage, reaction time and the ratio of Cl2 to N of disinfectant on genotoxicity of effluent of ozone-biological activated carbon (O3-BAC) during chlorine or chloramine disinfection were investigated using umu-test. It was found that, the genotoxicity of effluent of O3-BAC before disinfection ranged from 20-70 ng/L, and it increased after disinfection by chlorine or chloramines. With the same reaction time(24 h), genotoxicity after chlorination (40-95 ng/L) was higher than that after chloramination (20-40 ng/L) under same initial dosage. For chlorination, with initial dosage increasing from 0 mg/L to 10 mg/L, genotoxicity increased firstly, and got the maximum value at about 0.5-1 mg/L dosage, then decreased and got the minimum value at about 3-5 mg/L dosage, and finally increased again. For chloramination, genotoxicity didn't change that much. With the dosage of 3 mg/L and reaction time increasing from 0 h to 72 h, no matter for chlorine or chloramines disinfection, genotoxicity of effluent of O3-BAC both increased firstly, and got the maximum value at about 2 h, then decreased and got the minimum value at about 18 h, and finally increased again, and genotoxicity after chlorine disinfection (83-120 ng/L) was higher than that after chloramines disinfection (20-62 ng/L) under same reaction time. Further more, effects of the different ratios of Cl2 to N of disinfectant on genotoxicity of effluent of O3-BAC were also studied. Results of this study demonstrate that under test conditions, chloramine disinfection is safer than chlorine disinfection in the aspect of genotoxicity for drinking water, and the changes of genotoxicity are different from those of total HAAs.

  6. Nano-silver in drinking water and drinking water sources: stability and influences on disinfection by-product formation.

    PubMed

    Tugulea, A-M; Bérubé, D; Giddings, M; Lemieux, F; Hnatiw, J; Priem, J; Avramescu, M-L

    2014-10-01

    Nano-silver is increasingly used in consumer products from washing machines and refrigerators to devices marketed for the disinfection of drinking water or recreational water. The nano-silver in these products may be released, ending up in surface water bodies which may be used as drinking water sources. Little information is available about the stability of the nano-silver in sources of drinking water, its fate during drinking water disinfection processes, and its interaction with disinfection agents and disinfection by-products (DBPs). This study aims to investigate the stability of nano-silver in drinking water sources and in the finished drinking water when chlorine and chloramines are used for disinfection and to observe changes in the composition of DBPs formed when nano-silver is present in the source water. A dispersion of nano-silver particles (10 nm; PVP-coated) was used to spike untreated Ottawa River water, treated Ottawa River water, organic-free water, and a groundwater at concentrations of 5 mg/L. The diluted dispersions were kept under stirred and non-stirred conditions for up to 9 months and analyzed weekly using UV absorption to assess the stability of the nano-silver particles. In a separate experiment, Ottawa River water containing nano-silver particles (at 0.1 and 1 mg/L concentration, respectively) was disinfected by adding sodium hypochlorite (a chlorinating agent) in sufficient amounts to maintain a free chlorine residual of approximately 0.4 mg/L after 24 h. The disinfected drinking water was then quenched with ascorbic acid and analyzed for 34 neutral DBPs (trihalomethanes, haloacetonitriles, haloacetaldehydes, 1,1 dichloro-2-propanone, 1,1,1 trichloro-2-propanone, chloropicrin, and cyanogen chloride). The results were compared to the profile of DBPs obtained under the same conditions in the absence of nano-silver and in the presence of an equivalent concentration of Ag(+) ions (as AgNO3). The stability of the nano-silver dispersions in

  7. Nano-silver in drinking water and drinking water sources: stability and influences on disinfection by-product formation.

    PubMed

    Tugulea, A-M; Bérubé, D; Giddings, M; Lemieux, F; Hnatiw, J; Priem, J; Avramescu, M-L

    2014-10-01

    Nano-silver is increasingly used in consumer products from washing machines and refrigerators to devices marketed for the disinfection of drinking water or recreational water. The nano-silver in these products may be released, ending up in surface water bodies which may be used as drinking water sources. Little information is available about the stability of the nano-silver in sources of drinking water, its fate during drinking water disinfection processes, and its interaction with disinfection agents and disinfection by-products (DBPs). This study aims to investigate the stability of nano-silver in drinking water sources and in the finished drinking water when chlorine and chloramines are used for disinfection and to observe changes in the composition of DBPs formed when nano-silver is present in the source water. A dispersion of nano-silver particles (10 nm; PVP-coated) was used to spike untreated Ottawa River water, treated Ottawa River water, organic-free water, and a groundwater at concentrations of 5 mg/L. The diluted dispersions were kept under stirred and non-stirred conditions for up to 9 months and analyzed weekly using UV absorption to assess the stability of the nano-silver particles. In a separate experiment, Ottawa River water containing nano-silver particles (at 0.1 and 1 mg/L concentration, respectively) was disinfected by adding sodium hypochlorite (a chlorinating agent) in sufficient amounts to maintain a free chlorine residual of approximately 0.4 mg/L after 24 h. The disinfected drinking water was then quenched with ascorbic acid and analyzed for 34 neutral DBPs (trihalomethanes, haloacetonitriles, haloacetaldehydes, 1,1 dichloro-2-propanone, 1,1,1 trichloro-2-propanone, chloropicrin, and cyanogen chloride). The results were compared to the profile of DBPs obtained under the same conditions in the absence of nano-silver and in the presence of an equivalent concentration of Ag(+) ions (as AgNO3). The stability of the nano-silver dispersions in

  8. A NATIONWIDE DRINKING WATER DISINFECTION BY-PRODUCT OCCURRENCE STUDY - IDENTIFICATION OF NEW AND TOXICOLOGICALLY SIGNIFICANT COMPOUNDS WITH MASS SPECTROMETRY

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are formed when disinfectants, such as chlorine, react with natural organic matter and bromide present in the water. Chloroform was the first DBP identified in drinking water (in 1974), and was subsequently shown (along with other t...

  9. Reduced Efficiency of Chlorine Disinfection of Naegleria fowleri in a Drinking Water Distribution Biofilm.

    PubMed

    Miller, Haylea C; Wylie, Jason; Dejean, Guillaume; Kaksonen, Anna H; Sutton, David; Braun, Kalan; Puzon, Geoffrey J

    2015-09-15

    Naegleria fowleri associated with biofilm and biological demand water (organic matter suspended in water that consumes disinfectants) sourced from operational drinking water distribution systems (DWDSs) had significantly increased resistance to chlorine disinfection. N. fowleri survived intermittent chlorine dosing of 0.6 mg/L for 7 days in a mixed biofilm from field and laboratory-cultured Escherichia coli strains. However, N. fowleri associated with an attached drinking water distribution biofilm survived more than 30 times (20 mg/L for 3 h) the recommended concentration of chlorine for drinking water. N. fowleri showed considerably more resistance to chlorine when associated with a real field biofilm compared to the mixed laboratory biofilm. This increased resistance is likely due to not only the consumption of disinfectants by the biofilm and the reduced disinfectant penetration into the biofilm but also the composition and microbial community of the biofilm itself. The increased diversity of the field biofilm community likely increased N. fowleri's resistance to chlorine disinfection compared to that of the laboratory-cultured biofilm. Previous research has been conducted in only laboratory scale models of DWDSs and laboratory-cultured biofilms. To the best of our knowledge, this is the first study demonstrating how N. fowleri can persist in a field drinking water distribution biofilm despite chlorination. PMID:26287820

  10. Reduced Efficiency of Chlorine Disinfection of Naegleria fowleri in a Drinking Water Distribution Biofilm.

    PubMed

    Miller, Haylea C; Wylie, Jason; Dejean, Guillaume; Kaksonen, Anna H; Sutton, David; Braun, Kalan; Puzon, Geoffrey J

    2015-09-15

    Naegleria fowleri associated with biofilm and biological demand water (organic matter suspended in water that consumes disinfectants) sourced from operational drinking water distribution systems (DWDSs) had significantly increased resistance to chlorine disinfection. N. fowleri survived intermittent chlorine dosing of 0.6 mg/L for 7 days in a mixed biofilm from field and laboratory-cultured Escherichia coli strains. However, N. fowleri associated with an attached drinking water distribution biofilm survived more than 30 times (20 mg/L for 3 h) the recommended concentration of chlorine for drinking water. N. fowleri showed considerably more resistance to chlorine when associated with a real field biofilm compared to the mixed laboratory biofilm. This increased resistance is likely due to not only the consumption of disinfectants by the biofilm and the reduced disinfectant penetration into the biofilm but also the composition and microbial community of the biofilm itself. The increased diversity of the field biofilm community likely increased N. fowleri's resistance to chlorine disinfection compared to that of the laboratory-cultured biofilm. Previous research has been conducted in only laboratory scale models of DWDSs and laboratory-cultured biofilms. To the best of our knowledge, this is the first study demonstrating how N. fowleri can persist in a field drinking water distribution biofilm despite chlorination.

  11. Disinfection Byproduct Formation in Reverse-Osmosis Concentrated and Lyophilized Natural Organic Matter from a Drinking Water Source

    EPA Science Inventory

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking wa...

  12. INTEGRATED DISINFECTION BYPRODUCTS MIXTURES RESEARCH: COMPREHENSIVE CHARACTERIZATION OF WATER CONCENTRATES PREPARED FROM CHLORINATED AND OZONATED/POSTCHLORINATED DRINKING WATER

    EPA Science Inventory

    This article describes the disinfection byproduct (DBP) characterization portion of a series of experiments designed for comprehensive chemical and toxicological evaluation of two drinking water concentrates containing highly complex mixtures of DBP. This project, called the Four...

  13. Ultraviolet, chlorine and ozone disinfection of some enteroviruses in drinking water and treated effluents.

    PubMed

    Ali, M A

    1997-01-01

    The inactivation efficiency of chlorine, ultraviolet light and ozone were determined for poliovirus type 3, Coxsackievirus type B4 and Hepatitis A virus in drinking water and treated effluent. Ultraviolet was more efficient than the other two disinfectants at wave length 254 nm where no infective virus was detected after 4 min of UV irradiation in both drinking water and treated effluent. Inactivation by chlorine dose more than 25 mg/L was sufficient for studied viruses in both drinking water and treated effluent. Also virus-seeded drinking water was exposed to ozone for 18 min at ozone rate of 319 mg/L/h to obtain the maximum inactivation of PV3, CoxB4 and HAV but about 20 min of ozone exposure was needed for treated effluent. Physico-chemical parameters were measured before and after disinfection assay. No significant changes were observed.

  14. Comparative Evaluation of Alternative Disinfectants for Drinking Water and Wastewater Treatment

    EPA Science Inventory

    The Water Supply and Water Resources Division (WSWRD) of the U.S. Environmental Protection Agency’s (EPA) National Risk Management Research Laboratory (NRMRL) initiated a research program to evaluate the performance of various disinfectants that could potentially be used in drink...

  15. [The disinfection and preservation of drinking water with low-voltage pulsed electrical discharges].

    PubMed

    Avchinnikov, A V; Rakhmanin, Iu A; Zhuk, E G

    1995-01-01

    Two-hour exposure to low-voltage (2.8 to 3 kV) pulsed electric discharges (PED) effectively (by 99.9999%) disinfected drinking water. Preservation of water with IED had a pronounced bactericidal effect in respect of numerous pathogenic and opportunistic microorganisms. The aftereffect of PED persists for at least 2 months.

  16. Differential toxicity of drinking water disinfected with combinations of ultraviolet radiation and chlorine.

    PubMed

    Plewa, Michael J; Wagner, Elizabeth D; Metz, Deborah H; Kashinkunti, Ramesh; Jamriska, Katherine J; Meyer, Maria

    2012-07-17

    Alternative technologies to disinfect drinking water such as ultraviolet (UV) disinfection are becoming more widespread. The benefits of UV disinfection include reduced risk of microbial pathogens such as Cryptosporidium and reduced production of regulated drinking water disinfection byproducts (DBPs). The objective of this research was to determine if mammalian cell cytotoxicity and genotoxicity varied in response to different chlorination protocols with and without polychromatic medium pressure UV (MPUV) and monochromatic low pressure UV (LPUV) disinfection technologies. The specific aims were to analyze the mammalian cell cytotoxicity and genotoxicity of concentrated organic fractions from source water before and after chlorination and to determine the cytotoxicity and genotoxicity of the concentrated organic fractions from water samples treated with UV alone or UV before or after chlorination. Exposure of granular activated carbon-filtered Ohio River water to UV alone resulted in the lowest levels of mammalian cell cytotoxicity and genotoxicity. With combinations of UV and chlorine, the lowest levels of cytotoxicity and genotoxicity were observed with MPUV radiation. The best combined UV plus chlorine methodology that generated the lowest cytotoxicity and genotoxicity employed chlorination first followed by MPUV radiation. These data may prove important in the development of multibarrier methods of pathogen inactivation of drinking water, while limiting unintended toxic consequences.

  17. A new approach to evaluating the toxicity and genotoxicity of disinfected drinking water.

    PubMed

    Monarca, Silvano; Zani, Claudia; Richardson, Susan D; Thruston, Alfred D; Moretti, Massimo; Feretti, Donatella; Villarini, Milena

    2004-10-01

    The aim of this study was to evaluate the formation of toxic and genotoxic compounds in surface drinking waters treated with two widely used disinfectants, sodium hypochlorite (NaClO) and chlorine dioxide (ClO(2)), and a new disinfectant, peracetic acid (PAA). For this purpose a pilot plant was set up to add these biocides continuously to pre-filtered lake water flowing into three different basins. During three seasonal experiments, short-term in vivo tests (with plant, fish and molluscs) and in vitro tests (with bacteria, yeast and human cells) were carried out to evaluate the formation of genotoxic disinfection by-products (DBPs). Gas chromatography/mass spectrometry (GC/MS) was used to identify DBPs produced during the different treatments, microbiological analyses were performed to test the biocidal activity of the disinfectants, and chemical analyses were carried out to evaluate the quality of the water. The pilot drinking water plant under study was useful in studying the toxicity and genotoxicity of disinfected drinking water with this combined chemical/biotoxicological approach. This paper describes the setting up of the pilot plant and sets out/reports the results of the microbiological and chemical analyses.

  18. MULTISPECTRAL IDENTIFICATION OF CHLORINE DIOXIDE DISINFECTION BYPRODUCTS IN DRINKING WATER

    EPA Science Inventory

    This paper discusses the identification of organic disinfection byproducts (DBPs) at a pilot plant in Evansville, IN, which uses chlorine dioxide as a primary disinfectant. Unconventional multispectral identification techniques (gas chromatography combined with high- and low reso...

  19. Metagenomic Analyses of Drinking Water Receiving Different Disinfection Treatments

    EPA Science Inventory

    A metagenome-based approach was utilized for assessing the taxonomic affiliation and function potential of microbial populations in free chlorine (CHL) and monochloramine (CHM) treated drinking water (DW). A total of 1,024, 242 (averaging 544 bp) and 849, 349 (averaging 554 bp) ...

  20. Relationship of drinking water disinfectants to plasma cholesterol and thyroid hormone levels in experimental studies

    SciTech Connect

    Revis, N.W.; McCauley, P.; Bull, R.; Holdsworth, G.

    1986-03-01

    The effects of drinking water containing 2 or 15 ppm chlorine (pH 6.5 and 8.5), chlorine dioxide, and monochloramine on thyroid function and plasma cholesterol were studied because previous investigators have reported cardiovascular abnormalities in experimental animals exposed to chlorinated water. Plasma thyroxine (T4) levels, as compared to controls, were significantly decreased in pigeons fed a normal or high-cholesterol diet and drinking water containing these drinking water disinfectants at a concentration of 15 ppm (the exception was chlorine at pH 6.5) for 3 months. In most of the treatment groups, T4 levels were significantly lower following the exposure to drinking water containing the 2 ppm dose. Increase in plasma cholesterol were frequently observed in the groups with lower T4 levels. This association was most evident in pigeons fed the high-cholesterol diet and exposed to these disinfectants at a dose of 15 ppm. The factor(s) associated with the effect of these disinfectants on plasma T4 and cholesterol is not known. The authors suggest however that these effects are probably mediated by products formed when these disinfectants react with organic matter in the upper gastrointestinal tract.

  1. The effect of chlorine and combined chlorine/UV treatment on coliphages in drinking water disinfection.

    PubMed

    Zyara, Alyaa M; Torvinen, Eila; Veijalainen, Anna-Maria; Heinonen-Tanski, Helvi

    2016-08-01

    Chlorine disinfection is a globally used method to ensure the safety of drinking water. However, it has not always been successful against viruses and, therefore, it is important to find new methods to disinfect water. Seventeen different coliphages were isolated from the treated municipal wastewater. These coliphages and MS2 were treated with different dosages of chlorine in drinking water, and a combined chlorine/ultraviolet irradiation treatment for the chlorine-resistant coliphages. Chlorine disinfection with 0.3-0.5 mg/L total chlorine (free Cl-dosage 0.12-0.21 mg/L) for 10 min achieved 2.5-5.7 Log10-reductions for 11 sensitive coliphages. The six most resistant coliphages showed no reduction with these chlorine concentrations. MS2 was intermediate in chlorine resistance, and thus it is not a good indicator for viruses in chlorine disinfection. In the combined treatment total chlorine of 0.05-0.25 mg/L (free Cl-dosage 0.02-0.08 mg/L) and ultraviolet irradiation (14-22 mWs/cm(2)) were more effective than chlorine alone, and 3-5 Log10-reductions were achieved for the chlorine-resistant strains. The chlorination efficiency could be increased by higher dosages and longer contact times, but this could increase the formation of disinfection by-products. Therefore, the combination treatment is a recommended disinfection method. PMID:27441859

  2. The effect of chlorine and combined chlorine/UV treatment on coliphages in drinking water disinfection.

    PubMed

    Zyara, Alyaa M; Torvinen, Eila; Veijalainen, Anna-Maria; Heinonen-Tanski, Helvi

    2016-08-01

    Chlorine disinfection is a globally used method to ensure the safety of drinking water. However, it has not always been successful against viruses and, therefore, it is important to find new methods to disinfect water. Seventeen different coliphages were isolated from the treated municipal wastewater. These coliphages and MS2 were treated with different dosages of chlorine in drinking water, and a combined chlorine/ultraviolet irradiation treatment for the chlorine-resistant coliphages. Chlorine disinfection with 0.3-0.5 mg/L total chlorine (free Cl-dosage 0.12-0.21 mg/L) for 10 min achieved 2.5-5.7 Log10-reductions for 11 sensitive coliphages. The six most resistant coliphages showed no reduction with these chlorine concentrations. MS2 was intermediate in chlorine resistance, and thus it is not a good indicator for viruses in chlorine disinfection. In the combined treatment total chlorine of 0.05-0.25 mg/L (free Cl-dosage 0.02-0.08 mg/L) and ultraviolet irradiation (14-22 mWs/cm(2)) were more effective than chlorine alone, and 3-5 Log10-reductions were achieved for the chlorine-resistant strains. The chlorination efficiency could be increased by higher dosages and longer contact times, but this could increase the formation of disinfection by-products. Therefore, the combination treatment is a recommended disinfection method.

  3. Type of disinfectant in drinking water and patterns of mortality in Massachusetts

    SciTech Connect

    Zierler, S.; Danley, R.A.; Feingold, L.

    1986-11-01

    Chlorination has been the major strategy for disinfection of drinking water in the United States. Concern about the potential health effects of the reaction by-products of chlorine has prompted use of alternative strategies. One such method is chloramination, a treatment process that does not appear to have carcinogenic by-product, but may have less potent biocidal activity than chlorination. The authors examined the patterns of mortality of residents in Massachusetts who died between 1969 and 1983 and lived in communities using drinking water that was disinfected either by chlorine or chloramine. Comparison of type of disinfectant among 51,645 cases of deaths due to selected cancer sites and 214,998 controls who died from cardiovascular, cerebrovascular, or pulmonary disease, or from lymphatic cancer showed small variation in the patterns of mortality. Bladder cancer was moderately associated with residence at death in a chlorinated community in a logistic regression analysis using controls who die from lymphatic cancer. A slight excess of deaths from pneumonia and influenza was observed in communities whose residents drink chloraminated water compared to residents from chlorinated communities, as well as to all Massachusetts residents. These results are intended to be preliminary and crude descriptions of the relationship under study. The serious potential for misclassification of exposure status and errors in death certificate classification of cause of death affect the interpretability of the overall evidence that patterns of mortality are similar according to disinfectant in drinking water.

  4. REPRODUCTIVE AND DEVELOPMENTAL TOXICITY ASSOCIATED WITH DISINFECTION BY-PRODUCTS OF DRINKING WATER

    EPA Science Inventory

    Over the past decade many toxicologic studies have addressed the potential for disinfection byproducts of drinking water to elicit alterations on the reproductive system and fetal development.
    The types and designs of these studies vary considerably, but in general they can ...

  5. SURVEY OF HALONITROMETHANES AND IODOMETHANES: DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    This project involves the study of two classes of chemicals, halonitromethanes and iodomethanes, which have been found to be drinking water disinfection by-products (DBPs). Both have been predicted to have toxicity. In toxicity screening tests, bromonitromethanes have been shown ...

  6. DISINFECTION BY-PRODUCTS OF HEALTH CONCERN IN DRINKING WATER: RESULTS OF A NATIONWIDE OCCURRENCE STUDY

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are of concern because some epidemiologic studies have shown that some DBPs are associated with cancer or adverse reproductive/developmental effects in human populations, and other studies have shown that certain DBPs cause similar h...

  7. HALONITROMETHANE DRINKING WATER DISINFECTION BY-PRODUCTS: CHEMICAL CHARACTERIZATION AND MAMMALIAN CELL CYTOTOXICITY AND GENOTOXICITY

    EPA Science Inventory

    Halonitromethanes are drinking water disinfection by-products that have recently received a high priority for health effects research from the U.S. Environmental Protection Agency. Our purpose was to identify and synthesize where necessary the mixed halonitromethanes and to deter...

  8. ANIMAL MODELS FOR STUDYING MISCARRIAGE: ILLUSTRATION WITH STUDY OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Animal models for studying miscarriage: Illustration with study of drinking water disinfection by-products
    Authors & affiliations:
    Narotsky1, M.G. and S. Bielmeier Laffan2.
    1Reproductive Toxicology Division, NHEERL, ORD, U.S. Environmental Protection Agency, Research Tri...

  9. TRIBROMOPYRROLE, BROMINATED ACIDS, AND OTHER DISINFECTION BYPRODUCTS PRODUCED BY DISINFECTION OF DRINKING WATER RICH IN BROMIDE

    EPA Science Inventory

    Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comp...

  10. Transformation of pharmaceuticals during oxidation/disinfection processes in drinking water treatment.

    PubMed

    Postigo, Cristina; Richardson, Susan D

    2014-08-30

    Pharmaceuticals are emerging contaminants of concern and are widespread in the environment. While the levels of these substances in finished drinking waters are generally considered too low for human health concern, there are now concerns about their disinfection by-products (DBPs) that can form during drinking water treatment, which in some cases have been proven to be more toxic than the parent compounds. The present manuscript reviews the transformation products of pharmaceuticals generated in water during different disinfection processes, i.e. chlorination, ozonation, chloramination, chlorine dioxide, UV, and UV/hydrogen peroxide, and the main reaction pathways taking place. Most of the findings considered for this review come from controlled laboratory studies involving reactions of pharmaceuticals with these oxidants used in drinking water treatment.

  11. Tribromopyrrole, brominated acids, and other disinfection byproducts produced by disinfection of drinking water rich in bromide.

    PubMed

    Richardson, Susan D; Thruston, Alfred D; Rav-Acha, Chaim; Groisman, Ludmila; Popilevsky, Inna; Juraev, Olga; Glezer, Victor; McKague, A Bruce; Plewa, Michael J; Wagner, Elizabeth D

    2003-09-01

    Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comprehensive investigation of DBPs formed by chlorine dioxide under high bromide conditions. Drinking water from full-scale treatment plants in Israel was studied, along with source water (Sea of Galilee) treated under carefully controlled laboratory conditions. Select DBPs (trihalomethanes, haloacetic acids, aldehydes, chlorite, chlorate, and bromate) were quantified. Many of the DBPs identified have not been previously reported, and several of the identifications were confirmed through the analysis of authentic standards. Elevated bromide levels in the source water caused a significant shift in speciation to bromine-containing DBPs; bromoform and dibromoacetic acid were the dominant DBPs observed, with very few chlorine-containing compounds found. Iodo-trihalomethanes were also identified, as well as a number of new brominated carboxylic acids and 2,3,5-tribromopyrrole, which represents the first time a halogenated pyrrole has been reported as a DBP. Most of the bromine-containing DBPs were formed during pre-chlorination at the initial reservoir, and were not formed by chlorine dioxide itself. An exception wasthe iodo-THMs, which appeared to be formed by a combination of chlorine dioxide with chloramines or chlorine (either added deliberately or as an impurity in the chlorine dioxide). A separate laboratory study was also conducted to quantitatively determine the contribution of fulvic acids and humic acids (from isolated natural organic matter in the Sea of Galilee) as precursor material to several of the DBPs identified. Results showed that fulvic acid plays a greater role in the formation of THMs, haloacetic acids, and aldehydes, but 2,3,5-tribromopyrrole was produced primarily from humic

  12. Use of household bleach for emergency disinfection of drinking water.

    PubMed

    Elmaksoud, Sherif Abd; Patel, Nikita; Maxwell, Sherri L; Sifuentes, Laura Y; Gerba, Charles P

    2014-05-01

    Household bleach is typically used as a disinfectant for water in times of emergencies and by those engaging in recreational activities such as camping or rafting. The Centers for Disease Control and Prevention recommend a concentration of free chlorine of 1 mg/L for 30 minutes, or about 0.75 mL (1/8 teaspoon) of household bleach per gallon of water. The goal of the study described in this article was to assess two household bleach products to kill waterborne bacteria and viruses using the test procedures in the U.S. Environmental Protection Agency's Guide Standard and Protocol for Testing Microbiological Purifiers. Bleach was found to meet these requirements in waters of low turbidity and organic matter. While the test bacterium was reduced by six logs in high turbid and organic-laden waters, the test viruses were reduced only by one-half to one log. In such waters greater chlorine doses or contact times are needed to achieve greater reduction of viruses. PMID:24909009

  13. Use of household bleach for emergency disinfection of drinking water.

    PubMed

    Elmaksoud, Sherif Abd; Patel, Nikita; Maxwell, Sherri L; Sifuentes, Laura Y; Gerba, Charles P

    2014-05-01

    Household bleach is typically used as a disinfectant for water in times of emergencies and by those engaging in recreational activities such as camping or rafting. The Centers for Disease Control and Prevention recommend a concentration of free chlorine of 1 mg/L for 30 minutes, or about 0.75 mL (1/8 teaspoon) of household bleach per gallon of water. The goal of the study described in this article was to assess two household bleach products to kill waterborne bacteria and viruses using the test procedures in the U.S. Environmental Protection Agency's Guide Standard and Protocol for Testing Microbiological Purifiers. Bleach was found to meet these requirements in waters of low turbidity and organic matter. While the test bacterium was reduced by six logs in high turbid and organic-laden waters, the test viruses were reduced only by one-half to one log. In such waters greater chlorine doses or contact times are needed to achieve greater reduction of viruses.

  14. Reducing diarrhoea in Guatemalan children: randomized controlled trial of flocculant-disinfectant for drinking-water.

    PubMed Central

    Chiller, Tom M.; Mendoza, Carlos E.; Lopez, M. Beatriz; Alvarez, Maricruz; Hoekstra, Robert M.; Keswick, Bruce H.; Luby, Stephen P.

    2006-01-01

    OBJECTIVE: To examine the effect of a new point-of-use treatment for drinking-water, a commercially developed flocculant-disinfectant, on the prevalence of diarrhoea in children. METHODS: We conducted a randomized controlled trial among 514 rural Guatemalan households, divided into 42 neighbourhood clusters, for 13 weeks, from 4 November 2002 through 31 January 2003. Clusters assigned to water treatment with the flocculant-disinfectant were compared with those using their usual water-handling practices. The longitudinal prevalence of diarrhoea was calculated as the proportion of total days with diarrhoea divided by the total number of days of observation. The prevalence of diarrhoea was compared using the Wilcoxon rank-sum test. FINDINGS: The 1702 people in households receiving the disinfectant had a prevalence of diarrhoea that was 40% lower than that among the 1699 people using standard water-handling practices (0.9% versus 1.5%; P = 0.001). In households using the flocculant-disinfectant, children < 1 year of age had a 39% lower prevalence of diarrhoea than those in households using their standard practices (3.7% versus 6.0%; P = 0.005). CONCLUSION: In settings where families rarely treat drinking-water, we introduced a novel flocculant-disinfectant that reduced the longitudinal prevalence of diarrhoea, especially among children aged < 1 year, among whom diarrhoea has been strongly associated with mortality. Successful introduction and use of this product could contribute to preventing diarrhoeal disease globally. PMID:16501712

  15. Evidence that monochloramine disinfectant could lead to elevated Pb levels in drinking water.

    PubMed

    Switzer, Jay A; Rajasekharan, Vishnu V; Boonsalee, Sansanee; Kulp, Elizabeth A; Bohannan, Eric W

    2006-05-15

    Many water districts have recently shifted from free chlorine (in the form of HOCl/OCl-) to monochloramine (NH2-Cl) as a disinfectant for drinking water to lower the concentration of chlorinated hydrocarbon byproducts in the water. There is concern that the use of NH2Cl disinfectant may lead to higher Pb levels in drinking water. In this study, the electrochemical quartz crystal microbalance is used to compare the effects of these two disinfectants on the dissolution of Pb films. A 0.5 microm thick Pb film nearly completely dissolves in a NH2Cl solution, but it is passivated in a HOCl/OCl- solution. X-ray diffraction analysis shows that the NH2Cl oxidizes Pb to Pb(II) species such as Pb3-(OH)2(CO3)2, whereas the stronger oxidant, HOCl/OCl-, oxidizes Pb to Pb(IV) as an insoluble PbO2 conversion coating. Although NH2Cl may produce less halogenated organic byproducts than HOCl/OCl- when used as a disinfectant, it may lead to increased Pb levels in drinking water.

  16. Drinking Water FAQ

    MedlinePlus

    ... Water & Nutrition Camping, Hiking, Travel Drinking Water Treatment & Sanitation for Backcountry & Travel Use Emergency Disinfection of Drinking ... Drinking Water Healthy Swimming / Recreational Water Global Water, Sanitation, & Hygiene Other Uses of Water Water-related Emergencies & ...

  17. Disinfection aboard cruise liners and naval units: formation of disinfection by-products using chlorine dioxide in different qualities of drinking water.

    PubMed

    Ufermann, Petra; Petersen, Hauke; Exner, Martin

    2011-12-01

    The world-wide deployment of cruise liners and naval units has caused an increased need for the disinfection of drinking water. The main cause for this is the unknown quality of drinking water in foreign harbours--besides the formation of bio-films due to the climatically disadvantageous conditions in the operational area. Water conduits on board are currently disinfected with calcium hypochlorite in case of microbiological contamination. Chemical and physical analyses after disinfection with calcium hypochlorite have shown that organic by-products consisting of trihalomethanes develop in considerable amounts during disinfection. Furthermore, the method is susceptible to handling errors and thus often leads to insufficient disinfection results. Hitherto, the use of other disinfection methods allowed by government regulations, especially chlorine dioxide, is not widely spread. Unlike disinfection with calcium hypochlorite, chlorine dioxide does not lead to the formation of trihalomethanes. Typical disinfection by-products (DBP) are the anions chlorite and chlorate, which are formed in oxidative processes. The formation conditions of these anions have not yet been elucidated. For this reason, the probability of the generation of inorganic by-products after disinfection with chlorine dioxide has been determined, and their occurrence in drinking water on board has been examined with respect to a possible correlation between water quality and the formation of chlorate and chlorite. Therefore, a chromatographic method was developed and validated in order to determine the periodical development of chlorate and chlorite from chorine dioxide in purified water at different pH-values as well as in actual drinking water samples from water conduits on board. The formation of the by-products chlorite and chlorate after disinfection with chlorine dioxide is influenced neither by pH-value nor by chemical properties of the disinfected water. Considering the examined conditions

  18. Study of Disinfection By-Products and Long Term Storage of Drinking Water.

    NASA Astrophysics Data System (ADS)

    McGee, G.; White, D.; Garland, S.

    2002-12-01

    One of the challenges facing many of Alaska's communities is providing safe and reliable drinking water from sources containing high concentrations of natural organic material (NOM). These highly colored waters, locally referred to as "tundra tea," often result in the formation of disinfectant byproducts during treatment. Since surface water sources in the Arctic are often frozen for 6-9 months per year, communities are often forced to either store raw water for treatment during the winter or treat and store enough drinking water during the summer to last through the winter. Because long-term storage practices are somewhat unique to water treatment in the rural Northern communities, the practice has not been thoroughly studied and there is limited published information on how water quality is affected by extended storage. Anecdotal evidence and data collected by field engineers indicate that significant changes are occurring and that the quality of the treated water can be adversely impacted. The University of Alaska Small Drinking Water System Technical Assistance Center (ATTAC) is conducting fundamental and applied research to help Alaska's small communities provide safe and reliable drinking water. One research focus area is the formation of disinfection by-products (DBPs) in small drinking water systems. Studies to characterize the NOM present in Alaskan surface waters and demonstrations of NOM removal technologies have been have been conducted over the past several years. The study presented here examined the formation of disinfection by-products during long-term storage of water from five small Alaskan water systems. Results from this research suggest that long-term storage has a significant impact on DBP formation. The results suggest that the NOM escaping treatment is likely to react in the storage tank resulting in DBP concentrations that are well above the estimated DBP formation potential.

  19. ORD'S FOUR LAB STUDY: TOXICOLOGICAL AND CHEMICAL EVALUATION OF COMPLEX MIXTURES OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Disinfectants used in the production of drinking water react with naturally occurring organic and inorganic material in the source water to produce disinfection by-products (DBPs). Humans are exposed daily to a complex mixture of DBPs via oral, dermal, and inhalation routes. To ...

  20. Evaluation of an Innovative Approach to Validation of Ultraviolet (UV) Reactors for Disinfection in Drinking Water Systems

    EPA Science Inventory

    UV disinfection is an effective process for inactivating many microbial pathogens found in source waters with the potential as stand-alone treatment or in combination with other disinfectants. For surface and groundwater sourced drinking water applications, the U.S. Environmental...

  1. Drinking Water Disinfection by In-line Electrolysis: Product and Inorganic By-Product Formation

    NASA Astrophysics Data System (ADS)

    Bergmann, M. E. Henry

    This section covers peculiarities of so-called in-line electrolysis when drinking water is electrolysed to produce disinfection species killing microorganisms. Mainly mixed oxide electrodes (MIO) based on IrO2 and/or RuO2 coatings and boron-doped diamond electrodes were used in the studies. Artificial and real drinking water systems were electrolysed in continuous and discontinuous operating mode, varying water composition, current density and electrode materials. Results show, besides the ability of producing active chlorine, risks of inorganic disinfection by-products (DBPs) such as chlorate, perchlorate, nitrite, ammonium, chloramines, hydrogen peroxide and others. DBPs are responsible for analysis errors using DPD method for active chlorine measurements. Geometry may influence by-product yield. As a conclusion, the necessity of developing test routines for practical cell applications must be underlined.

  2. Response of Simulated Drinking Water Biofilm Mechanical and Structural Properties to Long-Term Disinfectant Exposure.

    PubMed

    Shen, Yun; Huang, Conghui; Monroy, Guillermo L; Janjaroen, Dao; Derlon, Nicolas; Lin, Jie; Espinosa-Marzal, Rosa; Morgenroth, Eberhard; Boppart, Stephen A; Ashbolt, Nicholas J; Liu, Wen-Tso; Nguyen, Thanh H

    2016-02-16

    Mechanical and structural properties of biofilms influence the accumulation and release of pathogens in drinking water distribution systems (DWDS). Thus, understanding how long-term residual disinfectants exposure affects biofilm mechanical and structural properties is a necessary aspect for pathogen risk assessment and control. In this study, elastic modulus and structure of groundwater biofilms was monitored by atomic force microscopy (AFM) and optical coherence tomography (OCT) during three months of exposure to monochloramine or free chlorine. After the first month of disinfectant exposure, the mean stiffness of monochloramine- or free-chlorine-treated biofilms was 4 to 9 times higher than those before treatment. Meanwhile, the biofilm thickness decreased from 120 ± 8 μm to 93 ± 6-107 ± 11 μm. The increased surface stiffness and decreased biofilm thickness within the first month of disinfectant exposure was presumably due to the consumption of biomass. However, by the second to third month during disinfectant exposure, the biofilm mean stiffness showed a 2- to 4-fold decrease, and the biofilm thickness increased to 110 ± 7-129 ± 8 μm, suggesting that the biofilms adapted to disinfectant exposure. After three months of the disinfectant exposure process, the disinfected biofilms showed 2-5 times higher mean stiffness (as determined by AFM) and 6-13-fold higher ratios of protein over polysaccharide, as determined by differential staining and confocal laser scanning microscopy (CLSM), than the nondisinfected groundwater biofilms. However, the disinfected biofilms and nondisinfected biofilms showed statistically similar thicknesses (t test, p > 0.05), suggesting that long-term disinfection may not significantly remove net biomass. This study showed how biofilm mechanical and structural properties vary in response to a complex DWDS environment, which will contribute to further research on the risk assessment and control of biofilm-associated-pathogens in DWDS.

  3. MUTAGENICITY IN SALMONELLA OF HALONITROMETHANES: A RECENTLY RECOGNIZED CLASS OF DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Halonitromethanes (HNMs) are a recently identified class of disinfection by-products in drinking water. They include chloronitromethane (CHN), dichloronitromethane (DCNM), trichloronitromethane (TCNM), bromonitromethane (BNM), dibromonitromethane (DBNM), tribromonitromethane (TBN...

  4. GESTATIONAL AND LACTATIONAL EFFECTS IN RATS OF SODIUM, SULFATE, AND CONCENTRATED DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Epidemiological and animal toxicity studies have raised concerns regarding possible adverse health effects of disinfection by-products (DBPs) in drinking water (DW). Because many DBPs are unidentified, we sought to evaluate DW concentrates. In preparation for a multigenerational ...

  5. Gestational and lactational effects in rats of sodium, sulfate, and concentrated disinfection by-products in drinking water

    EPA Science Inventory

    Epidemiological and animal toxicity studies have raised concerns regarding possible adverse health effects of disinfection by-products (DBPs) in drinking water (DW). Because many DBPs are unidentified, we sought to evaluate DW concentrates. In preparation for a multigenerational ...

  6. Acceptability of solar disinfection of drinking water treatment in Kathmandu Valley, Nepal.

    PubMed

    Rainey, Rochelle C; Harding, Anna K

    2005-10-01

    This research examines the acceptability of solar disinfection of drinking water (SODIS) in a village in Kathmandu Valley, Nepal, using constructs from the Health Belief Model as a framework to identify local understandings of water, sanitation and health issues. There has been no published research on the acceptability of SODIS in household testing in Nepal. Understanding the context of water and water purity in Nepalese villages is essential to identify culturally appropriate interventions to improve the quality of drinking water and health. Forty households from the village census list were randomly selected and the senior woman in each household was asked to participate. Baseline data on water sources and behaviors were collected in March 2002, followed by training in SODIS. Follow-up data were collected in June and July 2002. Only 9% of households routinely adopted SODIS. Participants mentioned the benefit of treating water to reduce stomach ailments, but this did not outweigh the perceived barriers of heavy domestic and agricultural workloads, other cultural barriers, uncertainty about the necessity of treating the water, and lack of knowledge that untreated drinking water causes diarrhea. Strategies for developing safe water systems must include public health education about waterborne diseases, source water protection, and a motivational component to achieve implementation and sustained use. In addition, other options for disinfecting water should be provided, given the women's work constraints and low level of formal education.

  7. Formation of nitrogenous disinfection by-products in 10 chlorinated and chloraminated drinking water supply systems.

    PubMed

    Liew, Deborah; Linge, Kathryn L; Joll, Cynthia A

    2016-09-01

    The presence of nitrogenous disinfection by-products (N-DBPs) in drinking water supplies is a public health concern, particularly since some N-DBPs have been reported to be more toxic than the regulated trihalomethanes and haloacetic acids. In this paper, a comprehensive evaluation of the presence of N-DBPs in 10 drinking water supply systems in Western Australia is presented. A suite of 28 N-DBPs, including N-nitrosamines, haloacetonitriles (HANs), haloacetamides (HAAms) and halonitromethanes (HNMs), were measured and evaluated for relationships with bulk parameters in the waters before disinfection. A number of N-DBPs were frequently detected in disinfected waters, although at generally low concentrations (<10 ng/L for N-nitrosamines and <10 μg/L for other N-DBPs) and below health guideline values where they exist. While there were no clear relationships between N-DBP formation and organic nitrogen in the pre-disinfection water, N-DBP concentrations were significantly correlated with dissolved organic carbon (DOC) and ammonia, and these, in addition to high bromide in one of the waters, led to elevated concentrations of brominated HANs (26.6 μg/L of dibromoacetonitrile). There were significant differences in the occurrence of all classes of N-DBPs between chlorinated and chloraminated waters, except for HNMs, which were detected at relatively low concentrations in both water types. Trends observed in one large distribution system suggest that N-DBPs can continue to form or degrade within distribution systems, and redosing of disinfectant may cause further by-product formation.

  8. Formation of nitrogenous disinfection by-products in 10 chlorinated and chloraminated drinking water supply systems.

    PubMed

    Liew, Deborah; Linge, Kathryn L; Joll, Cynthia A

    2016-09-01

    The presence of nitrogenous disinfection by-products (N-DBPs) in drinking water supplies is a public health concern, particularly since some N-DBPs have been reported to be more toxic than the regulated trihalomethanes and haloacetic acids. In this paper, a comprehensive evaluation of the presence of N-DBPs in 10 drinking water supply systems in Western Australia is presented. A suite of 28 N-DBPs, including N-nitrosamines, haloacetonitriles (HANs), haloacetamides (HAAms) and halonitromethanes (HNMs), were measured and evaluated for relationships with bulk parameters in the waters before disinfection. A number of N-DBPs were frequently detected in disinfected waters, although at generally low concentrations (<10 ng/L for N-nitrosamines and <10 μg/L for other N-DBPs) and below health guideline values where they exist. While there were no clear relationships between N-DBP formation and organic nitrogen in the pre-disinfection water, N-DBP concentrations were significantly correlated with dissolved organic carbon (DOC) and ammonia, and these, in addition to high bromide in one of the waters, led to elevated concentrations of brominated HANs (26.6 μg/L of dibromoacetonitrile). There were significant differences in the occurrence of all classes of N-DBPs between chlorinated and chloraminated waters, except for HNMs, which were detected at relatively low concentrations in both water types. Trends observed in one large distribution system suggest that N-DBPs can continue to form or degrade within distribution systems, and redosing of disinfectant may cause further by-product formation. PMID:27523603

  9. Occurrence and Comparative Toxicity of Haloacetaldehyde Disinfection Byproducts in Drinking Water.

    PubMed

    Jeong, Clara H; Postigo, Cristina; Richardson, Susan D; Simmons, Jane Ellen; Kimura, Susana Y; Mariñas, Benito J; Barcelo, Damia; Liang, Pei; Wagner, Elizabeth D; Plewa, Michael J

    2015-12-01

    The introduction of drinking water disinfection greatly reduced waterborne diseases. However, the reaction between disinfectants and natural organic matter in the source water leads to an unintended consequence, the formation of drinking water disinfection byproducts (DBPs). The haloacetaldehydes (HALs) are the third largest group by weight of identified DBPs in drinking water. The primary objective of this study was to analyze the occurrence and comparative toxicity of the emerging HAL DBPs. A new HAL DBP, iodoacetaldehyde (IAL) was identified. This study provided the first systematic, quantitative comparison of HAL toxicity in Chinese hamster ovary cells. The rank order of HAL cytotoxicity is tribromoacetaldehyde (TBAL) ≈ chloroacetaldehyde (CAL) > dibromoacetaldehyde (DBAL) ≈ bromochloroacetaldehyde (BCAL) ≈ dibromochloroacetaldehyde (DBCAL) > IAL > bromoacetaldehyde (BAL) ≈ bromodichloroacetaldehyde (BDCAL) > dichloroacetaldehyde (DCAL) > trichloroacetaldehyde (TCAL). The HALs were highly cytotoxic compared to other DBP chemical classes. The rank order of HAL genotoxicity is DBAL > CAL ≈ DBCAL > TBAL ≈ BAL > BDCAL>BCAL ≈ DCAL>IAL. TCAL was not genotoxic. Because of their toxicity and abundance, further research is needed to investigate their mode of action to protect the public health and the environment.

  10. Assessing microbiological water quality in drinking water distribution systems with disinfectant residual using flow cytometry.

    PubMed

    Gillespie, Simon; Lipphaus, Patrick; Green, James; Parsons, Simon; Weir, Paul; Juskowiak, Kes; Jefferson, Bruce; Jarvis, Peter; Nocker, Andreas

    2014-11-15

    Flow cytometry (FCM) as a diagnostic tool for enumeration and characterization of microorganisms is rapidly gaining popularity and is increasingly applied in the water industry. In this study we applied the method to obtain a better understanding of total and intact cell concentrations in three different drinking water distribution systems (one using chlorine and two using chloramines as secondary disinfectants). Chloramine tended to result in lower proportions of intact cells than chlorine over a wider residual range, in agreement with existing knowledge that chloramine suppresses regrowth more efficiently. For chlorinated systems, free chlorine concentrations above 0.5 mg L(-1) were found to be associated with relatively low proportions of intact cells, whereas lower disinfectant levels could result in substantially higher percentages of intact cells. The threshold for chlorinated systems is in good agreement with guidelines from the World Health Organization. The fact that the vast majority of samples failing the regulatory coliform standard also showed elevated proportions of intact cells suggests that this parameter might be useful for evaluating risk of failure. Another interesting parameter for judging the microbiological status of water, the biological regrowth potential, greatly varied among different finished waters providing potential help for investment decisions. For its measurement, a simple method was introduced that can easily be performed by water utilities with FCM capability.

  11. Integrated Disinfection By-Products Mixtures Research: Disinfection of Drinking Waters by Chlorination and Ozonation/Postchlorination Treatment Scenarios

    EPA Science Inventory

    This article describes disinfection of the same source water by two commonly used disinfection treatment scenarios for purposes of subsequent concentration, chemical analysis, and toxicological evaluation. Accompanying articles in this issue of the Journal of Toxicology and Envir...

  12. Solar disinfection of drinking water and diarrhoea in Maasai children: a controlled field trial.

    PubMed

    Conroy, R M; Elmore-Meegan, M; Joyce, T; McGuigan, K G; Barnes, J

    During December 1995-March 1996 in Kajiado Province, Kenya, 206 Maasai children, 5-16 years old, whose drinking water was contaminated with fecal coliform bacteria, were assigned 1.5 liter plastic bottles in which to store their drinking water. These bottles were re-used commercial table water bottles. The families of the children had only community sources for drinking water: 2 open water-holes and 1 tank fed from a piped supply. These water sources were not suited to chlorination. Scarce fuel and indoor air pollution precluded boiling water inside the hut. In the presence of their mothers, 108 children (the solar group) were told to fill the bottles with water at dawn, leave them in full sunlight on the roofs of their homes, and wait until midday before drinking from the bottles. The remaining 98 children (the control group) were told to leave the bottles in their homes. The purpose of the study was to evaluate the effect of solar disinfection on diarrheal disease in these Maasai children. Over a 12-week period, children in the solar group suffered fewer diarrhea episodes than those in the control group (4.1 vs. 4.5; adjusted odds ratio [AOR] = 0.66). They also were less likely to have diarrhea episodes severe enough to prevent them from doing their chores (1.7 vs. 2.3; AOR = 0.65). These findings suggest that solar disinfection of water may reduce diarrhea in communities with no access to other means of disinfection. PMID:8973432

  13. THE ROLE OF GC-MS AND LC-MS IN THE DISCOVERY OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Gas chromatography-mass spectrometry (GC-MS) has played a pivotal role in the discovery of disinfection by-products (DBPs) in drinking water. DBPs are formed when disinfectants, such as chlorine, ozone, chlorine dioxide or chloramine, react with natural organic matter in the wate...

  14. OCCURRENCE OF IODO-ACID AND IODO-THM DISINFECTION BY-PRODUCTS IN CHLORAMINATED DRINKING WATER

    EPA Science Inventory

    As part of a recent Nationwide Disinfection By-Product (DBP) Occurrence Study, iodo-acids were identified for the first time as DBPs in drinking water disinfected with chloramines. The iodo-acids identified included iodoacetic acid, bromoiodoacetic acid, (E)-3-bromo-3-iodo-prope...

  15. Drinking water quality and solar disinfection: effectiveness in peri-urban households in Nepal.

    PubMed

    Rainey, Rochelle C; Harding, Anna K

    2005-09-01

    The study examined pH, turbidity and fecal contamination of drinking water from household water storage containers, wells and taps, and the Godawari River, and tested the effectiveness of solar disinfection (SODIS) in reducing levels of fecal contamination from household containers. The research was conducted in 40 households in a village 6 km outside the capital city of Kathmandu, Nepal. Three rounds of data were collected: a baseline in March 2002 followed by training in solar disinfection, and follow-ups in June and July 2002. Untreated drinking water was found to have levels of contamination ranging from 0 to too numerous to count fecal coliform CFU 100ml(-1). Source water was significantly more contaminated than water from the household storage containers. Wells were less contaminated than taps. SODIS reduced the level of contamination under household conditions. Turbidity from taps was above 30 NTU in the rainy season, above the maximum for effective solar disinfection. SODIS was routinely adopted by only 10% of the participating households during the study.

  16. THE COMBINED CARCINOGENIC RISK FOR EXPOSURE TO MIXTURES OF DRINKING WATER DISINFECTION BY-PRODUCTS MAY BE LESS THAN ADDITIVE

    EPA Science Inventory

    The Combined Carcinogenic Risk for Exposure to Mixtures of Drinking Water Disinfection By-Products May be Less Than Additive

    Risk assessment methods for chemical mixtures in drinking water are not well defined. Current default risk assessments for chemical mixtures assume...

  17. Reproductive toxicity of a mixture of regulated drinking-water disinfection by-products in a multigenerational rat bioassay

    EPA Science Inventory

    BACKGROUND:Trihalomethanes (THMs) and haloaretic acids (HAAs) are regulated disinfection by-products (DBPs); their joint reproductive toxicity in drinking water is unknown.OBJECTIVE: We aimed to evaluate a drinking water mixture of the four regulated THMs and five regulated HAAs ...

  18. Feasibility of the silver-UV process for drinking water disinfection.

    PubMed

    Butkus, Michael A; Talbot, Mark; Labare, Michael P

    2005-12-01

    A synergistic effect between cationic silver and UV radiation (silver-UV disinfection) has been observed that can appreciably enhance inactivation of viruses. The purpose of this work was to assess the feasibility of this technique for drinking water disinfection and evaluate the effects of selected impurities, found in fresh water, and common parameters on inactivation of the coliphage MS-2 with the silver-UV process. Turbidity (kaolin), calcium hardness, carbonate alkalinity, and pH did not significantly degrade inactivation. Inactivation was reduced in the presence of chloride, at concentrations greater than 30 mg/L, and in water samples with UV-254 absorbance values greater than ca. 0.1 cm(-1). Inactivation of MS-2 with silver-UV disinfection was also reduced at high phosphate concentrations (above ca. 5 mM). Silver-UV inactivation of MS-2 increased with increases in temperature between 10 and 20 degrees C. Silver-UV inactivation of MS-2 was increased by greater than 1-log over UV alone, in two untreated fresh water sources, which indicates that silver-UV may be a viable treatment technology. An assessment of operation and management costs suggests that an increase in inactivation of MS-2 with silver-UV disinfection could be economically beneficial.

  19. New chlorinated amphetamine-type-stimulants disinfection-by-products formed during drinking water treatment.

    PubMed

    Huerta-Fontela, Maria; Pineda, Oriol; Ventura, Francesc; Galceran, Maria Teresa

    2012-06-15

    Previous studies have demonstrated high removal rates of amphetamine-type-stimulants (ATSs) through conventional drinking water treatments; however the behaviour of these compounds through disinfection steps and their transformation into disinfection-by-products (DBPs) is still unknown. In this work, for the first time, the reactivity of some ATSs such as amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyethylamphetamine (MDEA) with chlorine has been investigated under simulated and real drinking water treatment conditions in order to evaluate their ability to give rise to transformation products. Two new DBPs from these illicit drugs have been found. A common chlorinated-by-product (3-chlorobenzo)-1,3-dioxole, was identified for both MDA and MDEA while for MDMA, 3-chlorocatechol was found. The presence of these DBPs in water samples collected through drinking water treatment was studied in order to evaluate their formation under real conditions. Both compounds were generated through treatment from raw river water samples containing ATSs at concentration levels ranging from 1 to 15 ng/L for MDA and from 2.3 to 78 ng/L for MDMA. One of them, (3-chlorobenzo)-1,3-dioxole, found after the first chlorination step, was eliminated after ozone and GAC treatment while the MDMA DBP mainly generated after the postchlorination step, showed to be recalcitrant and it was found in final treated waters at concentrations ranging from 0.5 to 5.8 ng/L.

  20. Human cell toxicogenomic analysis of bromoacetic acid: a regulated drinking water disinfection by-product.

    PubMed

    Muellner, Mark G; Attene-Ramos, Matias S; Hudson, Matthew E; Wagner, Elizabeth D; Plewa, Michael J

    2010-04-01

    The disinfection of drinking water is a major achievement in protecting the public health. However, current disinfection methods also generate disinfection by-products (DBPs). Many DBPs are cytotoxic, genotoxic, teratogenic, and carcinogenic and represent an important class of environmentally hazardous chemicals that may carry long-term human health implications. The objective of this research was to integrate in vitro toxicology with focused toxicogenomic analysis of the regulated DBP, bromoacetic acid (BAA) and to evaluate modulation of gene expression involved in DNA damage/repair and toxic responses, with nontransformed human cells. We generated transcriptome profiles for 168 genes with 30 min and 4 hr exposure times that did not induce acute cytotoxicity. Using qRT-PCR gene arrays, the levels of 25 transcripts were modulated to a statistically significant degree in response to a 30 min treatment with BAA (16 transcripts upregulated and nine downregulated). The largest changes were observed for RAD9A and BRCA1. The majority of the altered transcript profiles are genes involved in DNA repair, especially the repair of double strand DNA breaks, and in cell cycle regulation. With 4 hr of treatment the expression of 28 genes was modulated (12 upregulated and 16 downregulated); the largest fold changes were in HMOX1 and FMO1. This work represents the first nontransformed human cell toxicogenomic study with a regulated drinking water disinfection by-product. These data implicate double strand DNA breaks as a feature of BAA exposure. Future toxicogenomic studies of DBPs will further strengthen our limited knowledge in this growing area of drinking water research.

  1. Do Iodine Contrast Media Compounds Used for Medical Imaging Contribute to the Formation of Iodinated Disinfection By-Products in Drinking Water?

    EPA Science Inventory

    Iodinated disinfection byproducts (DBPs) have recently gained attention due to their cyto- and genotoxicity and increased formation in drinking water treated with chloramine, which has become an increasingly popular disinfectant in the United States. One of these—iodoacetic acid...

  2. Disinfection of drinking water by using a novel electrochemical reactor employing carbon-cloth electrodes.

    PubMed Central

    Matsunaga, T; Nakasono, S; Takamuku, T; Burgess, J G; Nakamura, N; Sode, K

    1992-01-01

    A novel electrochemical reactor employing carbon-cloth electrodes was constructed for disinfection of drinking water. Escherichia coli K-12 (10(2) cells per cm3) was sterilized when a cell suspension was passed through the reactor at a dilution rate of 6.0 h-1, and a potential of 0.7 V versus a saturated calomel electrode was applied to an electrode. The survival ratio increased with increasing dilution rate but was less than 0.1% at dilution rates of less than 6.0 h-1. Although the survival ratio increased with increasing cell concentration above 10(3) cells per cm3, the disinfection rate also increased. The disinfection rate was 6.0 x 10(2) cells per cm3 per h at a cell concentration of 10(2) cells per cm3. Continuous sterilization of E. coli cells was carried out for 24 h. Sterilization is based on an electrochemical reaction between the electrode and the cell which is mediated by intracellular coenzyme A. Sterilization of drinking water by using this reactor was successfully performed, demonstrating the potential of such a reactor for clean and efficient water purification. PMID:1610189

  3. Synergistic effect of solar radiation and solar heating to disinfect drinking water sources.

    PubMed

    Rijal, G K; Fujioka, R S

    2001-01-01

    Waterborne diseases are still common in developing countries as drinking water sources are contaminated and feasible means to reliably treat and disinfect these waters are not available. Many of these developing countries are in the tropical regions of the world where sunlight is plentiful. The objective of this study was to evaluate the effectiveness of combining solar radiation and solar heating to disinfect contaminated water using a modified Family Sol*Saver System (FSP). The non-UV transmittable cover sheet of the former FSP system was replaced with an UV transmittable plastic cover sheet to enable more wavelengths of sunlight to treat the water. Disinfection efficiency of both systems was evaluated based on reduction of the natural populations of faecal coliform, E. coli, enterococci, C. perfringens, total heterotrophic bacteria, hydrogen sulphide producing bacteria and FRNA virus. The results showed that under sunny and partly sunny conditions, water was heated to critical temperature (60 degrees C) in both the FSP systems inactivating more than 3 log (99.9%) of the concentrations of faecal coliform and E. coli to undetectable levels of < 1 CFU/100 mL within 2-5 h exposure to sunlight. However, under cloudy conditions, the two FSP systems did not reduce the concentrations of faecal indicator bacteria to levels of < 1 CFU/100 mL. Nonetheless, sufficient evidence was obtained to show that UV radiation of sunlight plus heat worked synergistically to enhance the inactivation of faecal indicator bacteria. The relative log removal of indicator microorganism in the FSP treated water was total heterotrophic bacteria < C. perfringens < F RNA virus < enterococci < E. coli < faecal coliform. In summary, time of exposure to heat and radiation effects of sunlight were important in disinfecting water by solar units. The data indicated that direct radiation of sunlight worked synergistically with solar heating of the water to disinfect the water. Thus, effective

  4. Synergistic effect of solar radiation and solar heating to disinfect drinking water sources.

    PubMed

    Rijal, G K; Fujioka, R S

    2001-01-01

    Waterborne diseases are still common in developing countries as drinking water sources are contaminated and feasible means to reliably treat and disinfect these waters are not available. Many of these developing countries are in the tropical regions of the world where sunlight is plentiful. The objective of this study was to evaluate the effectiveness of combining solar radiation and solar heating to disinfect contaminated water using a modified Family Sol*Saver System (FSP). The non-UV transmittable cover sheet of the former FSP system was replaced with an UV transmittable plastic cover sheet to enable more wavelengths of sunlight to treat the water. Disinfection efficiency of both systems was evaluated based on reduction of the natural populations of faecal coliform, E. coli, enterococci, C. perfringens, total heterotrophic bacteria, hydrogen sulphide producing bacteria and FRNA virus. The results showed that under sunny and partly sunny conditions, water was heated to critical temperature (60 degrees C) in both the FSP systems inactivating more than 3 log (99.9%) of the concentrations of faecal coliform and E. coli to undetectable levels of < 1 CFU/100 mL within 2-5 h exposure to sunlight. However, under cloudy conditions, the two FSP systems did not reduce the concentrations of faecal indicator bacteria to levels of < 1 CFU/100 mL. Nonetheless, sufficient evidence was obtained to show that UV radiation of sunlight plus heat worked synergistically to enhance the inactivation of faecal indicator bacteria. The relative log removal of indicator microorganism in the FSP treated water was total heterotrophic bacteria < C. perfringens < F RNA virus < enterococci < E. coli < faecal coliform. In summary, time of exposure to heat and radiation effects of sunlight were important in disinfecting water by solar units. The data indicated that direct radiation of sunlight worked synergistically with solar heating of the water to disinfect the water. Thus, effective

  5. Effect of solar disinfection on viability of intestinal protozoa in drinking water.

    PubMed

    Gaafar, Maha R

    2007-04-01

    The effect of solar disinfection on the viability of intestinal protozoa Giardia lamblia, Microsporidia sp., Cryptosporidium parvum, Cyclospora cyatenensis and Entamoeba histolytica in drinking water was studied as compared to chlorine disinfection. The protozoa were collected from stool samples, to infect to the distilled water. Chlorinated water samples were prepared at concentration of 4 ppm, and the parasites were incubated overnight at room temperature with the treated water. Sun treatment was applied for 2 exposures (6 & 24 hrs), in summer and winter. Sun treated water samples were put in tubes and exposed to sun. The 2 disinfection methods were tested in plastic and glass test tubes. Parasites viability was assessed by viability assay using trypan blue stain (0.4%), and bioassay infectivity tests in experimentally laboratory bred mice. Results proved that all parasites' viability was not affected by chlorine, following solar disinfection treatment, parasites became dark blue in colour and deformed by trypan blue stain. High parasites death was recorded for all parasites except Microsporidia sp. Bioassay infectivity test showed a statistically significant reduction in mean number of all parasites in intestinal sections compared to controls. The best results were tubes exposure to sun for 24 hrs in summer, where G. lamblia, C. parvum and C. cyatenensis were inactivated or absence in intestinal sections. No statistically significant difference was between the use of plastic and glass tubes, either in chlorine or sun treated parasites. So, solar disinfection proved a simple, cheap and effective means for improving water for human use, particularly in developing countries. PMID:17580569

  6. Formation and occurrence of new polar iodinated disinfection byproducts in drinking water.

    PubMed

    Pan, Yang; Li, Wenbin; An, Hao; Cui, Hao; Wang, Ying

    2016-02-01

    During drinking water disinfection, iodinated disinfection byproducts (I-DBPs) can be generated through reactions between iodide, disinfectants, and natural organic matter. Drinking water I-DBPs have been increasingly attracting attention as emerging organic pollutants as a result of their significantly higher toxicity and growth inhibition than their chloro- and bromo-analogues. In this study, by adopting ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry precursor ion scan, multiple reaction monitoring, and product ion scan analyses, 11 new polar I-DBPs with confirmed structures and eight new polar I-DBPs with proposed structures were detected in simulated drinking water samples. Chloramination of simulated raw waters containing natural organic matter with higher aromaticity produced higher levels of new phenolic I-DBPs. Formation of new polar I-DBPs and total organic iodine (TOI) was most favored in chloramination, followed by chlorine dioxide treatment, and relatively minor in chlorination. Lower pH in chloramination substantially enhanced the formation of new polar I-DBPs and TOI. NH2Cl and dissolved organic nitrogen could be important nitrogen sources and precursors for formation of the two new nitrogenous phenolic I-DBPs. Notably, in tap water samples collected from nine major cities located in the Yangtze River Delta region of China, seven of the 11 new polar I-DBPs with confirmed structures were detected at levels from 0.11 to 28 ng/L, and the two new nitrogenous phenolic I-DBPs were ubiquitous with concentrations from 0.12 to 24 ng/L, likely due to the relatively high dissolved organic nitrogen levels in regional source waters.

  7. Formation and occurrence of new polar iodinated disinfection byproducts in drinking water.

    PubMed

    Pan, Yang; Li, Wenbin; An, Hao; Cui, Hao; Wang, Ying

    2016-02-01

    During drinking water disinfection, iodinated disinfection byproducts (I-DBPs) can be generated through reactions between iodide, disinfectants, and natural organic matter. Drinking water I-DBPs have been increasingly attracting attention as emerging organic pollutants as a result of their significantly higher toxicity and growth inhibition than their chloro- and bromo-analogues. In this study, by adopting ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry precursor ion scan, multiple reaction monitoring, and product ion scan analyses, 11 new polar I-DBPs with confirmed structures and eight new polar I-DBPs with proposed structures were detected in simulated drinking water samples. Chloramination of simulated raw waters containing natural organic matter with higher aromaticity produced higher levels of new phenolic I-DBPs. Formation of new polar I-DBPs and total organic iodine (TOI) was most favored in chloramination, followed by chlorine dioxide treatment, and relatively minor in chlorination. Lower pH in chloramination substantially enhanced the formation of new polar I-DBPs and TOI. NH2Cl and dissolved organic nitrogen could be important nitrogen sources and precursors for formation of the two new nitrogenous phenolic I-DBPs. Notably, in tap water samples collected from nine major cities located in the Yangtze River Delta region of China, seven of the 11 new polar I-DBPs with confirmed structures were detected at levels from 0.11 to 28 ng/L, and the two new nitrogenous phenolic I-DBPs were ubiquitous with concentrations from 0.12 to 24 ng/L, likely due to the relatively high dissolved organic nitrogen levels in regional source waters. PMID:26606185

  8. Microbiological effectiveness and cost of boiling to disinfect drinking water in rural Vietnam.

    PubMed

    Clasen, Thomas F; Thao, Do Hoang; Boisson, Sophie; Shipin, Oleg

    2008-06-15

    Despite certain shortcomings, boiling is still the most common means of treating water in the home and the benchmark against which alternative household-based disinfection and filtration methods must be measured. We assessed the microbiological effectiveness and cost of boiling among a vulnerable population relying on unimproved water sources and commonly practicing boiling as a means of disinfecting water. In a 12 week study among 50 households from a rural community in Vietnam, boiling was associated with a 97% reduction in geometric mean thermotolerant coliforms (TTCs) (p < 0.001). Despite high levels of faecal contamination in source water, 37% of stored water samples from self-reported boilers met the WHO standard for safe drinking water (0 TTC/100 mL), and 38.3% fell within the low risk category (1--10 TTC/100 mL). Nevertheless, 60.5% of stored drinking water samples were positive for TTC, with 22.2% falling into the medium risk category (11--100 TTC/100 mL). The estimated cost of wood used to boil water was US$ 0.272 per month for wood collectors and US$ 1.68 per month for wood purchasers, representing approximately 0.48% to 1.04%, respectively, of the average monthly income of participating households.

  9. DEVELOPMENT OF A NOVEL METHOD FOR ANALYSIS OF TRANSCRIPTIONAL CHANGES IN TRANSITIONAL EPITHELIUM FROM URINARY BLADDERS OF RATS EXPOSED TO DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory


    Development of a Novel Method for Analysis of Transcriptional Changes in Transitional Epithelium from Urinary Bladders of Rats Exposed to Drinking Water Disinfection By- products.

    Epidemiologic studies in human populations that drink chemically disinfected drinking wa...

  10. Evidence of arsenic release promoted by disinfection by-products within drinking-water distribution systems.

    PubMed

    Andra, Syam S; Makris, Konstantinos C; Botsaris, George; Charisiadis, Pantelis; Kalyvas, Harris; Costa, Costas N

    2014-02-15

    Changes in disinfectant type could trigger a cascade of reactions releasing pipe-anchored metals/metalloids into finished water. However, the effect of pre-formed disinfection by-products on the release of sorbed contaminants (arsenic-As in particular) from drinking water distribution system pipe scales remains unexplored. A bench-scale study using a factorial experimental design was performed to evaluate the independent and interaction effects of trihalomethanes (TTHM) and haloacetic acids (HAA) on arsenic (As) release from either scales-only or scale-biofilm conglomerates (SBC) both anchored on asbestos/cement pipe coupons. A model biofilm (Pseudomonas aeruginosa) was allowed to grow on select pipe coupons prior experimentation. Either TTHM or HAA individual dosing did not promote As release from either scales only or SBC, detecting <6 μg AsL(-1) in finished water. In the case of scales-only coupons, the combination of the highest spike level of TTHM and HAA significantly (p<0.001) increased dissolved and total As concentrations to levels up to 16 and 95 μg L(-1), respectively. Similar treatments in the presence of biofilm (SBC) resulted in significant (p<0.001) increase in dissolved and total recoverable As up to 20 and 47 μg L(-1), respectively, exceeding the regulatory As limit. Whether or not, our laboratory-based results truly represent mechanisms operating in disinfected finished water in pipe networks remains to be investigated in the field.

  11. Effect of disinfectant, water age, and pipe materials on bacterial and eukaryotic community structure in drinking water biofilm.

    PubMed

    Wang, Hong; Masters, Sheldon; Edwards, Marc A; Falkinham, Joseph O; Pruden, Amy

    2014-01-01

    Availability of safe, pathogen-free drinking water is vital to public health; however, it is impossible to deliver sterile drinking water to consumers. Recent microbiome research is bringing new understanding to the true extent and diversity of microbes that inhabit water distribution systems. The purpose of this study was to determine how water chemistry in main distribution lines shape the microbiome in drinking water biofilms and to explore potential associations between opportunistic pathogens and indigenous drinking water microbes. Effects of disinfectant (chloramines, chlorine), water age (2.3 days, 5.7 days), and pipe material (cement, iron, PVC) were compared in parallel triplicate simulated water distribution systems. Pyrosequencing was employed to characterize bacteria and terminal restriction fragment polymorphism was used to profile both bacteria and eukaryotes inhabiting pipe biofilms. Disinfectant and water age were both observed to be strong factors in shaping bacterial and eukaryotic community structures. Pipe material only influenced the bacterial community structure (ANOSIM test, P < 0.05). Interactive effects of disinfectant, pipe material, and water age on both bacteria and eukaryotes were noted. Disinfectant concentration had the strongest effect on bacteria, while dissolved oxygen appeared to be a major driver for eukaryotes (BEST test). Several correlations of similarity metrics among populations of bacteria, eukaryotes, and opportunistic pathogens, as well as one significant association between mycobacterial and proteobacterial operational taxonomic units, provides insight into means by which manipulating the microbiome may lead to new avenues for limiting the growth of opportunistic pathogens (e.g., Legionella) or other nuisance organisms (e.g., nitrifiers).

  12. Bioanalytical assessment of the formation of disinfection byproducts in a drinking water treatment plant.

    PubMed

    Neale, Peta A; Antony, Alice; Bartkow, Michael E; Farré, Maria José; Heitz, Anna; Kristiana, Ina; Tang, Janet Y M; Escher, Beate I

    2012-09-18

    Disinfection of drinking water is the most successful measure to reduce water-borne diseases and protect health. However, disinfection byproducts (DBPs) formed from the reaction of disinfectants such as chlorine and monochloramine with organic matter may cause bladder cancer and other adverse health effects. In this study the formation of DBPs through a full-scale water treatment plant serving a metropolitan area in Australia was assessed using in vitro bioanalytical tools, as well as through quantification of halogen-specific adsorbable organic halogens (AOXs), characterization of organic matter, and analytical quantification of selected regulated and emerging DBPs. The water treatment train consisted of coagulation, sand filtration, chlorination, addition of lime and fluoride, storage, and chloramination. Nonspecific toxicity peaked midway through the treatment train after the chlorination and storage steps. The dissolved organic matter concentration decreased after the coagulation step and then essentially remained constant during the treatment train. Concentrations of AOXs increased upon initial chlorination and continued to increase through the plant, probably due to increased chlorine contact time. Most of the quantified DBPs followed a trend similar to that of AOXs, with maximum concentrations observed in the final treated water after chloramination. The mostly chlorinated and brominated DBPs formed during treatment also caused reactive toxicity to increase after chlorination. Both genotoxicity with and without metabolic activation and the induction of the oxidative stress response pathway showed the same pattern as the nonspecific toxicity, with a maximum activity midway through the treatment train. Although measured effects cannot be directly translated to adverse health outcomes, this study demonstrates the applicability of bioanalytical tools to investigate DBP formation in a drinking water treatment plant, despite bioassays and sample preparation not

  13. Nitrogenous disinfection byproducts in English drinking water supply systems: Occurrence, bromine substitution and correlation analysis.

    PubMed

    Bond, Tom; Templeton, Michael R; Mokhtar Kamal, Nurul Hana; Graham, Nigel; Kanda, Rakesh

    2015-11-15

    Despite the recent focus on nitrogenous disinfection byproducts in drinking water, there is limited occurrence data available for many species. This paper analyses the occurrence of seven haloacetonitriles, three haloacetamides, eight halonitromethanes and cyanogen chloride in 20 English drinking water supply systems. It is the first survey of its type to compare bromine substitution factors (BSFs) between the haloacetamides and haloacetonitriles. Concentrations of the dihalogenated haloacetonitriles and haloacetamides were well correlated. Although median concentrations of these two groups were lower in chloraminated than chlorinated surface waters, median BSFs for both in chloraminated samples were approximately double those in chlorinated samples, which is significant because of the higher reported toxicity of the brominated species. Furthermore, median BSFs were moderately higher for the dihalogenated haloacetamides than for the haloacetonitriles. This indicates that, while the dihalogenated haloacetamides were primarily generated from hydrolysis of the corresponding haloacetonitriles, secondary formation pathways also contributed. Median halonitromethane concentrations were remarkably unchanging for the different types of disinfectants and source waters: 0.1 μg · mgTOC(-1) in all cases. Cyanogen chloride only occurred in a limited number of samples, yet when present its concentrations were higher than the other N-DBPs. Concentrations of cyanogen chloride and the sum of the halonitromethanes were not correlated with any other DBPs.

  14. Reducing the chlorine dioxide demand in final disinfection of drinking water treatment plants using activated carbon.

    PubMed

    Sorlini, Sabrina; Biasibetti, Michela; Collivignarelli, Maria Cristina; Crotti, Barbara Marianna

    2015-01-01

    Chlorine dioxide is one of the most widely employed chemicals in the disinfection process of a drinking water treatment plant (DWTP). The aim of this work was to evaluate the influence of the adsorption process with granular activated carbon (GAC) on the chlorine dioxide consumption in final oxidation/disinfection. A first series of tests was performed at the laboratory scale employing water samples collected at the outlet of the DWTP sand filter of Cremona (Italy). The adsorption process in batch conditions with seven different types of GAC was studied. A second series of tests was performed on water samples collected at the outlet of four GAC columns installed at the outlet of the DWTP sand filter. The results showed that the best chlorine dioxide demand (ClO2-D) reduction yields are equal to 60-80% and are achieved in the first 30 min after ClO2 addition, during the first 16 days of the column operation using a mineral, coal-based, mesoporous GAC. Therefore, this carbon removes organic compounds that are more rapidly reactive with ClO2. Moreover, a good correlation was found between the ClO2-D and UV absorbance at wavelength 254 nm using mineral carbons; therefore, the use of a mineral mesoporous GAC is an effective solution to control the high ClO2-D in the disinfection stage of a DWTP.

  15. QUENCHING OF CHLORINATION DISINFECTION BY-PRODUCT FORMATION IN DRINKING WATER BY HYDROGEN PEROXIDE. (R825362)

    EPA Science Inventory

    Reactions between chlorine disinfectants, dissolved organic matter, and other chemicals in water form a series of disinfection by-products (DBPs), including trihalomethanes (THMs) and haloacetic acids (HAAs), that are toxic and subject to increasingly stringent regulations. Th...

  16. Predictive model for disinfection by-product in Alexandria drinking water, northern west of Egypt.

    PubMed

    Abdullah, Ali M; Hussona, Salah El-dien

    2013-10-01

    Chlorine has been utilized in the early stages of water treatment processes as disinfectant. Disinfection for drinking water reduces the risk of pathogenic infection but may pose a chemical threat to human health due to disinfection residues and their by-products (DBP) when the organic and inorganic precursors are present in water. In the last two decades, many modeling attempts have been made to predict the occurrence of DBP in drinking water. Models have been developed based on data generated in laboratory-scale and field-scale investigations. The objective of this paper is to develop a predictive model for DBP formation in the Alexandria governorate located at the northern west of Egypt based on field-scale investigations as well as laboratory-controlled experimentations. The present study showed that the correlation coefficient between trihalomethanes (THM) predicted and THM measured was R (2)=0.88 and the minimum deviation percentage between THM predicted and THM measured was 0.8 %, the maximum deviation percentage was 89.3 %, and the average deviation was 17.8 %, while the correlation coefficient between dichloroacetic acid (DCAA) predicted and DCAA measured was R (2)=0.98 and the minimum deviation percentage between DCAA predicted and DCAA measured was 1.3 %, the maximum deviation percentage was 47.2 %, and the average deviation was 16.6 %. In addition, the correlation coefficient between trichloroacetic acid (TCAA) predicted and TCAA measured was R (2)=0.98 and the minimum deviation percentage between TCAA predicted and TCAA measured was 4.9 %, the maximum deviation percentage was 43.0 %, and the average deviation was 16.0 %.

  17. Why do people stop treating contaminated drinking water with Solar Water Disinfection (SODIS)?

    PubMed

    Tamas, Andrea; Mosler, Hans-Joachim

    2011-08-01

    Solar Water Disinfection (SODIS) is a simple method designed to treat microbiologically contaminated drinking water at household level. This article characterizes relapse behavior in comparison with continued SODIS use after a 7-month nonpromotion period. In addition, different subtypes among relapsers and continuers were assumed to diverge mainly in their intention to use SODIS and their degree of cognition intensity. Data were taken from a longitudinal SODIS promotion study. Cluster analyses were applied to find subtypes among 166 relapsers and 123 continuers. Overall relapsers have lower values for all psychological variables compared to overall continuers. A low-value and a high-value relapser subtype as well as a low-value and a high-value continuer subtype were found. Low-value relapsers differ from high-value relapsers in one central belief (taste), in affective connotation, social norms, and dissonance. Interestingly, high-value relapsers have values almost as high as low-value continuers, differing only in their degree of habit. Only high-value continuers seem to be stable and did not show a decrease in critical habit variables over time. The different subtypes are placed along the behavior change process, and possible interventions for each type are highlighted.

  18. MUTAGENICITY IN SALMONELLA AND DNA DAMAGE IN THE CHO/COMET ASSAY INDUCED BY NITROHALOMETHANES, A NOVEL CLASS OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Mutagenicity in Salmonella and DNA Damage in the CHO/Comet Assay Induced by Nitrohalomethanes, a Novel Class of Drinking Water Disinfection By-Products.

    Halomethanes are a class of drinking water disinfection by-products (DBPs) whose genotoxicity has been studied extensi...

  19. EFFECTS OF 20 WEEK EXPOSURES IN FEMALE SPRAGUE-DAWLEY (S-D) RATS TO THE DRINKING WATER DISINFECTION BY-PRODUCT DIBROMOACETIC ACID

    EPA Science Inventory

    Effects of 20 week exposures in female Sprague-Dawley (S-D) rats to the drinking water disinfection by-product dibromoacetic acid. A S Murr and J M Goldman, Endocrinol. Br., RTD, NHEERL, ORD, US EPA, Res. Tri. Pk, NC. Sponsor: Audrey Cummings

    The drinking water disinfect...

  20. EFFECTS OF 20 WEEK EXPOSURES IN FEMALE SPRAGUE-DAWLEY (S-D) RATS TO DIBROMOACETIC ACID, A DRINKING WATER DISINFECTANT BY-PRODUCT

    EPA Science Inventory

    Effects of 20 week exposures in female Sprague-Dawley (S-D) rats to the drinking water disinfection by-product dibromoacetic acid. A S Murr and J M Goldman, Endocrinol. Br., RTD, NHEERL, ORD, US EPA, Res. Tri. Pk, NC. Sponsor: Audrey Cummings

    The drinking water disinfect...

  1. OXIDATIVE DNA DAMAGE AND REPAIR IN RATS TREATED WITH POTASSIUM BROMATE AND A MIXTUE OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Oxidative DNA Damage and Repair in Rats Treated with Potassium Bromate and a Mixture of Drinking Water Disinfection By-Products

    Public drinking water treated with chemical disint'ectants contains a complex mixture of disinfection by-products (D BPs). There is a need for m...

  2. Tracking disinfection by-products and arsenic removal during various drinking water treatment trains.

    PubMed

    Tubić, Aleksandra; Dalmacija, Bozo; Agbaba, Jasmina; Ivancev-Tumbas, Ivana; Klasnja, Mile; Dalmacija, Milena

    2010-01-01

    In the central Banat region (Northern Serbia), groundwater is used as a drinking water source. Raw water originates from a 40-80 m and 100-150 m deep layer. It contains a high amount of natural organic matter (DOC = 9.17+/-0.87 mg C/L) with a trihalomethanes formation potential of 448+/-88.2 microg/L and a haloacetic acid formation potential of 174+/-68.9 microg/L. A high amount of arsenic (86.0+/-3.4 microg/L) is also found in this water. This study used a pilot-scale system to investigate the possibilities of combining polyaluminium chloride and ferrous-chloride to remove disinfection by-products precursors and arsenic by coagulation. Two treatment trains with different pre-treatment steps were investigated (ozone vs. H2O2/O3). For the final water polishing, filtration with granulated activated carbon (GAC) was applied. Both investigated treatment lines achieved a satisfactory chemical water quality. Simulation of disinfection conditions was performed and the contents of trihalomethanes and haloacetic acids measured, to investigate whether the chemical quality of the water remained satisfactory over a 48 hour period.

  3. A feasibility study of cumulative risk assessment methods for drinking water disinfection by-product mixtures.

    PubMed

    Teuschler, Linda K; Rice, Glenn E; Wilkes, Charles R; Lipscomb, John C; Power, Fred W

    Humans are exposed daily to complex mixtures of chemicals, including drinking water disinfection by-products (DBPs) via oral, dermal, and inhalation routes. Some positive epidemiological and toxicological studies suggest reproductive and developmental effects and cancer are associated with consumption of chlorinated drinking water. Thus, the U.S. Environmental Protection Agency (EPA) conducted research to examine the feasibility of evaluating simultaneous exposures to multiple DBPs via all three exposure routes. A cumulative risk assessment approach was developed for DBP mixtures by combining exposure modeling and physiologically based pharmacokinetic modeling results with a new mixtures risk assessment method, the cumulative relative potency factors (CRPF) approach. Internal doses were estimated for an adult female and an adult male, each of reproductive age, and for a child (age 6 yr) inclusive of oral, dermal, and inhalation exposures. Estimates of the daily internal doses were made for 13 major DBPs, accounting for activity patterns that affect the amount of human contact time with drinking water (e.g., tap water consumed, time spent showering), building characteristics (e.g., household air volumes), and physicochemical properties of the DBPs (e.g., inhalation rates, skin permeability rates, blood: air partition coefficients). A novel cumulative risk assessment method, the CRPF approach, is advanced that integrates the principles of dose addition and response addition to produce multiple-route, chemical mixture risk estimates using total absorbed doses. Research needs to improve this approach are presented.

  4. [Effect of ammonia-oxidizing bacteria (AOB) on chloraminated disinfection attenuation in drinking water distribution system].

    PubMed

    Bai, Xiao-Hui; Cai, Yun-Long; Zhou, Bin-Hui; Zhi, Xing-Hua

    2009-06-15

    The growth of microbe and formation of biofilm in water distribution system were important factors affecting the security of water quality. The number of ammonia-oxidizing bacteria (AOB) in biofilm of a chloraminated drinking water distribution system in Shanghai was detected by MPN-Griess method, and the relations among AOB, nitrification and chloraminated disinfection were analyzed. Meanwhile, the effects of AOB on chloraminated disinfection fastness and attenuation by simulation experiment were studied. The result indicated that the number of ammonia-oxidizing bacteria in pipe biofilm was between 1.0 x 10(2)-4.3 x 10(5) MPN/g dry biofilm. Correlation coefficients of AOB with ammonia, nitrite and nitrate were -0.563, 0.603 and -0.563. Correlation coefficients of AOB with total chlorine and mono-chloramine were -0.659 and -0.571. Fastness of AOB to chloramine was higher than heterotrophic bacteria and AOB can deplete more chloramine than HPC.

  5. Comparative genotoxicity of nitrosamine drinking water disinfection byproducts in Salmonella and mammalian cells.

    PubMed

    Wagner, Elizabeth D; Hsu, Kang-Mei; Lagunas, Angelica; Mitch, William A; Plewa, Michael J

    2012-01-24

    Nitrosamine water disinfection byproducts (DBPs) are an emerging class of non-halogenated, nitrogen-containing water contaminants. Five nitrosamine DBPs were analyzed for genotoxicity (N-nitrosodimethylamine (NDMA), N-nitrosopiperidine (NPIP), N-nitrosopyrrolidine (NPYR), N-nitrosomorpholine (NMOR) and N-nitrosodiphenylamine (NDPhA). Using Salmonella typhimurium strain YG7108 the descending rank order of mutagenicity was NDMA>NPIP>NMOR>NPYR; NDPhA was not mutagenic. We developed and calibrated an exogenous S9 mix that was highly effective in activating NDMA in Chinese hamster ovary (CHO) cells using the SCGE (Comet) assay. The descending rank order for genotoxicity was NDMA>NPIP>NMOR. NDPhA was genotoxic only at one concentration and NPYR was not genotoxic. The genotoxic potencies in S. typhimurium and CHO cells were highly correlated. Based on their comparative genotoxicity attention should be focused on the generation and occurrence of NDMA, NPIP and NMOR. Current drinking water disinfection processes may need to be modified such that the generation of nitrosamine DBPs is effectively limited in order to protect the environment and the public health.

  6. The Occurrence and Toxicity of Disinfection Byproducts in European Drinking Waters in Relation with the HIWATE Epidemiology Study

    PubMed Central

    Jeong, Clara H.; Wagner, Elizabeth D.; Siebert, Vincent R.; Anduri, Sridevi; Richardson, Susan D.; Daiber, Eric J.; McKague, A. Bruce; Kogevinas, Manolis; Villanueva, Cristina M.; Goslan, Emma H.; Luo, Wentai; Isabelle, Lorne M.; Pankow, James F.; Grazuleviciene, Regina; Cordier, Sylvaine; Edwards, Susan C.; Righi, Elena; Nieuwenhuijsen, Mark J.; Plewa, Michael J.

    2012-01-01

    The HIWATE (Health Impacts of long-term exposure to disinfection byproducts in drinking WATEr) project was a systematic analysis that combined the epidemiology on adverse pregnancy outcomes and other health effects with long term exposure to low levels of drinking water disinfection byproducts (DBPs) in the European Union. The present study focused on the relationship of the occurrence and concentration of DBPs with in vitro mammalian cell toxicity. Eleven drinking water samples were collected from 5 European countries. Each sampling location corresponded with an epidemiological study for the HIWATE program. Over 90 DBPs were identified; the range in the number of DBPs and their levels reflected the diverse collection sites, different disinfection processes, and the different characteristics of the source waters. For each sampling site, chronic mammalian cell cytotoxicity correlated highly with the numbers of DBPs identified and the levels of DBP chemical classes. Although there was a clear difference in the genotoxic responses among the drinking waters, these data did not correlate as well with the chemical analyses. Thus, the agents responsible for the genomic DNA damage observed in the HIWATE samples may be due to unresolved associations of combinations of identified DBPs, unknown emerging DBPs that were not identified, or other toxic water contaminants. This study represents the first to integrate quantitative in vitro toxicological data with analytical chemistry and human epidemiologic outcomes for drinking water DBPs. PMID:22958121

  7. Combining Mass Spectrometry and Toxicology for a Multi-Country European Epidemiologic Study on Drinking Water Disinfection By-Products.

    EPA Science Inventory

    The HiWATE (Health Impacts of long-term exposure to disinfection by-products in drinking WATEr) project is the first systematic analysis that combines the epidemiology on adverse pregnancy outcomes with analytical chemistry and analytical biology in the European Union. This study...

  8. Combining Mass Spectrometry and Toxicology for a Multi-Country European Epidemiologic Study on Drinking Water Disinfection By-Products

    EPA Science Inventory

    The HiWATE (Health Impacts of long-term exposure to disinfection by-products in drinking WATEr) project is the first systematic analysis that combines the epidemiology on adverse pregnancy outcomes with analytical chemistry and analytical biology in the European Union. This study...

  9. TOXICITY-BASED IDENTIFICATION OF DRINKING WATER DISINFECTION BY-PRODUCTS USING ESI-MS AND ESI-MS/MS

    EPA Science Inventory

    The goal of this research is to use a bio-assay directed approach to focus identification work on the most toxicologically important disinfection by-products. To this end, drinking water is being collected from full-scale treatment plants that use chlorine, ozone, chlorine dioxi...

  10. INVESTIGATIONS INTO THE GC/MS DECOMPOSITION OF TRIBROMONITROMETHANE IN DRINKING WATER DISINFECTION BY-PRODUCT ANALYSIS

    EPA Science Inventory

    Tribromonitromethane (bromopicrin) has been found to be a disinfection by-product (DBP) in
    chlorinated1 and ozonated2 drinking water, and is structurally similar to dibromonitromethane,
    which has been indicated through structural analysis to be a possible carcinogen. Bromop...

  11. OCCURRENCE, GENOTOXICITY, AND CARCINOGENICITY OF EMERGING DISINFECTION BY-PRODUCTS IN DRINKING WATER: A REVIEW AND ROADMAP FOR RESEARCH

    EPA Science Inventory

    Occurrence, Genotoxicity, and Carcinogenicity of Emerging Disinfection By-products in Drinking Water: A Review and Roadmap for Research
    Summary of Paper
    What is study?
    This is the first review of the 30 year's research effort on the occurrence, genotoxicity,...

  12. BIOTRANSFORMATION AND GENOTOXICITY OF THE DRINKING WATER DISINFECTION BYPRODUCT BROMODICHLOROMETHANE: DNA BINDING MEDIATED BY GLUTATHIONE TRANSFERASE THETA 1-1

    EPA Science Inventory

    The drinking water disinfection byproduct bromodichloromethane (CHBrCl2) was
    previously shown to be mutagenic in Salmonella typhimurium that overexpress rat glutathione
    transferase theta 1-1 (GSTT1-1). Several experimental approaches were undertaken in this study
    to inve...

  13. IDENTIFICATION OF PROTEINS INVOLVED IN TESTICULAR TOXICITY INDUCED BY HALOACID BY-PRODUCTS OF DRINKING WATER DISINFECTION

    EPA Science Inventory

    Dibromoacetic acid (DBA), a prevalent disinfection by-product in drinking water, perturbs spermiogenesis in adult rats suggesting that Sertoli-germ cell communication is compromised. When isolated seminiferous tubules from rats exposed to DBA in vivo were cultured, quantitative a...

  14. DISINFECTION BY-PRODUCTS OF HEALTH CONCERN IN DRINKING WATER: RESULTS OF A U.S. NATIONWIDE OCCURRENCE STUDY

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are of concern because some epidemiologic studies have shown that some DBPs are associated with cancer or adverse reproductive/developmental effects in human populations, and other studies have shown that certain DBPs cause similar h...

  15. TOXICITY-BASED IDENTIFICATION OF DRINKING WATER DISINFECTION BY-PRODUCTS USING LC/MS AND LC/MS/MS

    EPA Science Inventory

    The goal of this research is to use a bio-assay directed approach to focus identification work on the most toxicologically important disinfection by-products. To this end, drinking water is being collected from full-scale treatment plants that use chlorine, ozone, chlorine dioxi...

  16. THE CARCINOGENIC RESPONSE TO A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS (DBP) WAS LESS THAN ADDITIVE

    EPA Science Inventory

    THE CARCINOGENIC RESPONSE TO A MIXTURE OF DRINKING WATER DISINFECTION BY -PRODUCTS (DBP) W AS LESS THAN ADDITIVE.

    Current default risk assessments for chemical mixtures assume additivity of carcinogenic effects but this may under or over represent the actual biological res...

  17. RENAL CARCINOGENICITY OF INDIVIDUAL AND A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS (DBP) IN EKER RATS

    EPA Science Inventory

    RENAL CARCINOGENICITY OF INDIVIDUAL AND A MIXTURE OF DRINKING / WATER DISINFECTION BY -PRODUCTS (DBP) IN EKER RATS.

    Eker rats develop hereditary renal cell carcinoma secondary to a germline mutation in the tuberous sclerosis 2 tumor suppressor gene, and are highly suscepti...

  18. EPIDEMIOLOGIC EVALUATION OF THE POTENTIAL ASSOCIATION BETWEEN EXPOSURE TO DRINKING WATER DISINFECTION BY-PRODUCTS (DBP) AND SEMEN QUALITY

    EPA Science Inventory

    Epidemiologic Evaluation of the Potential Association between Exposure to Drinking Water Disinfection By-Products and Semen Quality
    *Morris, R; +Olshan, A; +Lansdell, L; *Jeffay, S; *Strader, L; *Klinefelter, G; *Perreault, S.

    * U.S. EPA/ORD/NHEERL/RTD/GEEBB, Research ...

  19. Exposure estimates to disinfection by-products of chlorinated drinking water.

    PubMed Central

    Weisel, C P; Kim, H; Haltmeier, P; Klotz, J B

    1999-01-01

    Exposure to disinfection by-products (DBPs) of drinking water is multiroute and occurs in households serviced by municipal water treatment facilities that disinfect the water as a necessary step to halt the spread of waterborne infectious diseases. Biomarkers of the two most abundant groups of DBPs of chlorination, exhaled breath levels of trihalomethanes (THMs) and urinary levels of two haloacetic acids, were compared to exposure estimates calculated from in-home tap water concentrations and responses to a questionnaire related to water usage. Background THM breath concentrations were uniformly low. Strong relationships were identified between the THM breath concentrations collected after a shower and both the THM water concentration and the THM exposure from a shower, after adjusting for the postshower delay time in collecting the breath sample. Urinary haloacetic acid excretion rates were not correlated to water concentrations. Urinary trichloroacetic acid excretion rates were correlated with ingestion exposure, and that correlation was stronger in a subset of individuals who consumed beverages primarily within their home where the concentration measurements were made. No correlation was observed between an average 48-hr exposure estimate and the urinary dichloroacetic acid excretion rate, presumably because of its short biological half-life. Valid biomarkers were identified for DBP exposures, but the time between the exposure and sample collection should be considered to account for different metabolic rates among the DBPs. Further, using water concentration as an exposure estimate can introduce misclassification of exposure for DBPs whose primary route is ingestion due to the great variability in the amount of water ingested across a population. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9924004

  20. Quantification of pathogen inactivation efficacy by free chlorine disinfection of drinking water for QMRA.

    PubMed

    Petterson, S R; Stenström, T A

    2015-09-01

    To support the implementation of quantitative microbial risk assessment (QMRA) for managing infectious risks associated with drinking water systems, a simple modeling approach for quantifying Log10 reduction across a free chlorine disinfection contactor was developed. The study was undertaken in three stages: firstly, review of the laboratory studies published in the literature; secondly, development of a conceptual approach to apply the laboratory studies to full-scale conditions; and finally implementation of the calculations for a hypothetical case study system. The developed model explicitly accounted for variability in residence time and pathogen specific chlorine sensitivity. Survival functions were constructed for a range of pathogens relying on the upper bound of the reported data transformed to a common metric. The application of the model within a hypothetical case study demonstrated the importance of accounting for variable residence time in QMRA. While the overall Log10 reduction may appear high, small parcels of water with short residence time can compromise the overall performance of the barrier. While theoretically simple, the approach presented is of great value for undertaking an initial assessment of a full-scale disinfection contactor based on limited site-specific information.

  1. Quantification of pathogen inactivation efficacy by free chlorine disinfection of drinking water for QMRA.

    PubMed

    Petterson, S R; Stenström, T A

    2015-09-01

    To support the implementation of quantitative microbial risk assessment (QMRA) for managing infectious risks associated with drinking water systems, a simple modeling approach for quantifying Log10 reduction across a free chlorine disinfection contactor was developed. The study was undertaken in three stages: firstly, review of the laboratory studies published in the literature; secondly, development of a conceptual approach to apply the laboratory studies to full-scale conditions; and finally implementation of the calculations for a hypothetical case study system. The developed model explicitly accounted for variability in residence time and pathogen specific chlorine sensitivity. Survival functions were constructed for a range of pathogens relying on the upper bound of the reported data transformed to a common metric. The application of the model within a hypothetical case study demonstrated the importance of accounting for variable residence time in QMRA. While the overall Log10 reduction may appear high, small parcels of water with short residence time can compromise the overall performance of the barrier. While theoretically simple, the approach presented is of great value for undertaking an initial assessment of a full-scale disinfection contactor based on limited site-specific information. PMID:26322749

  2. Biological mechanism for the toxicity of haloacetic acid drinking water disinfection byproducts.

    PubMed

    Pals, Justin A; Ang, Justin K; Wagner, Elizabeth D; Plewa, Michael J

    2011-07-01

    The halogenated acetic acids are a major class of drinking water disinfection byproducts (DBPs) with five haloacetic acids regulated by the U.S. EPA. These agents are cytotoxic, genotoxic, mutagenic, and teratogenic. The decreasing toxicity rank order of the monohalogenated acetic acids (monoHAAs) is iodo- > bromo- > chloroacetic acid. We present data that the monoHAAs inhibit glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity in a concentration-dependent manner with the same rank order as above. The rate of inhibition of GAPDH and the toxic potency of the monoHAAs are highly correlated with their alkylating potential and the propensity of the halogen leaving group. This strong association between GAPDH inhibition and the monoHAA toxic potency supports a comprehensive mechanism for the adverse biological effects by this widely occurring class of regulated DBPs.

  3. Molecular structure of a new chlorinated disinfection by-product in drinking water

    NASA Astrophysics Data System (ADS)

    Gong, Huijuan; Wang, Huaqin; You, Zhen; Zou, Huixian; Shen, Xing

    2005-06-01

    A new found chlorinated disinfection by-product (DBP) in drinking water was isolated and characterized by MS, FTIR, 1H and 13C NMR spectroscopy. Single crystal X-ray diffraction method was also carried out to determinate the exact structure of the compound. The crystal is of monoclinic, and space group P2 1/ m with a=7.8800(16), b=6.7950(14), c=8.8350(18) Å, β=115.02(3)°, V=428.67(15) Å 3, Z=4, Dc=1.778 g/cm 3, μ=1.028 mm -1 and F(000)=228, R=0.0510 and wR=0.2205 for 982 unique reflections with 918 observed ones [ I>2 σ( I)]. The results confirmed the structure of this compound. It was finally identified as 2,2,4-trichloro-5-methoxy-cyclopent-4-ene-1,3-dione (TCMCD).

  4. Occurrence, profiling and prioritization of halogenated disinfection by-products in drinking water of China.

    PubMed

    Ding, Huanhuan; Meng, Liping; Zhang, Haifeng; Yu, Jianwei; An, Wei; Hu, Jianying; Yang, Min

    2013-07-01

    The occurrence of 28 disinfection by-products (DBPs), which were divided into 5 groups, in 70 drinking water treatment plants in 31 cities across China was investigated, and the toxic potency of each DBP group was calculated using mammalian cell toxicity data from previous studies for profiling. Of the 28 DBPs, 21 were detected with an average frequency of detection of 50%. Trihalomethanes (THM4) and haloacetic acids (HAAs) were the most predominant species, whose median concentration levels were at 10.53 and 10.95 μg L(-1), respectively. Two of four iodinated trihalomethanes (I-THMs) were detected, and the concentration of the I-THMs ranged from under the detection limit to 5.58 μg L(-1). The total concentration of haloacetonitriles (HANs) in different water samples ranged from under the limit of detection to 39.20 μg L(-1), with a median concentration of 1.11 μg L(-1). Two of four halonitromethanes (HNMs) were detected, and the maximum concentrations of chloronitromethane (CNM) and trichloronitromethane (TCNM) were 0.96 and 0.28 μg L(-1), respectively. HANs were found to be the most potent DBP group in terms of cytotoxicity, and HANs and HAAs had the same level of genotoxic potency. These results indicate that although at a low concentration level, the toxic potency of the unregulated HANs in drinking water may not be neglected. PMID:23743579

  5. Occurrence, profiling and prioritization of halogenated disinfection by-products in drinking water of China.

    PubMed

    Ding, Huanhuan; Meng, Liping; Zhang, Haifeng; Yu, Jianwei; An, Wei; Hu, Jianying; Yang, Min

    2013-07-01

    The occurrence of 28 disinfection by-products (DBPs), which were divided into 5 groups, in 70 drinking water treatment plants in 31 cities across China was investigated, and the toxic potency of each DBP group was calculated using mammalian cell toxicity data from previous studies for profiling. Of the 28 DBPs, 21 were detected with an average frequency of detection of 50%. Trihalomethanes (THM4) and haloacetic acids (HAAs) were the most predominant species, whose median concentration levels were at 10.53 and 10.95 μg L(-1), respectively. Two of four iodinated trihalomethanes (I-THMs) were detected, and the concentration of the I-THMs ranged from under the detection limit to 5.58 μg L(-1). The total concentration of haloacetonitriles (HANs) in different water samples ranged from under the limit of detection to 39.20 μg L(-1), with a median concentration of 1.11 μg L(-1). Two of four halonitromethanes (HNMs) were detected, and the maximum concentrations of chloronitromethane (CNM) and trichloronitromethane (TCNM) were 0.96 and 0.28 μg L(-1), respectively. HANs were found to be the most potent DBP group in terms of cytotoxicity, and HANs and HAAs had the same level of genotoxic potency. These results indicate that although at a low concentration level, the toxic potency of the unregulated HANs in drinking water may not be neglected.

  6. The epidemiology and possible mechanisms of disinfection by-products in drinking water.

    PubMed

    Nieuwenhuijsen, Mark J; Grellier, James; Smith, Rachel; Iszatt, Nina; Bennett, James; Best, Nicky; Toledano, Mireille

    2009-10-13

    This paper summarizes the epidemiological evidence for adverse health effects associated with disinfection by-products (DBPs) in drinking water and describes the potential mechanism of action. There appears to be good epidemiological evidence for a relationship between exposure to DBPs, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers including colorectal cancer is inconclusive and inconsistent. There appears to be some evidence for an association between exposure to DBPs, specifically THMs, and little for gestational age/intrauterine growth retardation and, to a lesser extent, pre-term delivery, but evidence for relationships with other outcomes such as low birth weight, stillbirth, congenital anomalies and semen quality is inconclusive and inconsistent. Major limitations in exposure assessment, small sample sizes and potential biases may account for the inconclusive and inconsistent results in epidemiological studies. Moreover, most studies have focused on total THMs as the exposure metric, whereas other DBPs appear to be more toxic than the THMs, albeit generally occurring at lower levels in the water. The mechanisms through which DBPs may cause adverse health effects including cancer and adverse reproductive effects have not been well investigated. Several mechanisms have been suggested, including genotoxicity, oxidative stress, disruption of folate metabolism, disruption of the synthesis and/or secretion of placental syncytiotrophoblast-derived chorionic gonadotropin and lowering of testosterone levels, but further work is required in this area.

  7. Relationship of dietary iodide and drinking water disinfectants to thyroid function in experimental animals

    SciTech Connect

    Revis, N.W.; McCauley, P.; Holdsworth, G.

    1986-11-01

    The importance of dietary iodide on the reported hypothyroid effect of drinking water disinfectants on thyroid function was investigated. Previous studies have also showed differences in the relative sensitivity of pigeons and rabbits to chlorinated water. Pigeons and rabbits were exposed for 3 months to diets containing high (950 ppb) or low (300 ppb) levels of iodide and to drinking water containing two levels of chlorine. Results showed that the high-iodide diet prevented the hypothyroid effect observed in pigeons given the low-iodide diet and chlorinated drinking water. Similar trends were observed in rabbits exposed to the same treatment; however, significant hypothyroid effects were not observed in this animal model. The factor associated with the observed effect of dietary iodide on the chlorine-induced change in thyroid function is unknown, as is the relative sensitivity of rabbits and pigeons to the effect of chlorine. Several factors may explain the importance of dietary iodide and the relative sensitivity of these species. For example, the iodine formed by the known reaction of chlorine with iodide could result in a decrease in the plasma level of iodide because of the relative absorption rates of iodide and iodine in the intestinal tract, and the various types and concentrations of chloroorganics (metabolites) formed in the diet following the exposure of various dietary constituents to chlorine could affect the thyroid function. The former factor was investigated in the present studies. Results do not confirm a consistent, significant reduction in the plasma level of iodide in rabbits and pigeons exposed to chlorinated water and the low-iodide diet. The latter factor is being investigated.

  8. Developmental Toxicity Evaluations of Whole Mixtures of Disinfection By-products using Concentrated Drinking Water in Rats: Gestational and Lactational Effects of Sulfate and Sodium*

    EPA Science Inventory

    A developmental toxicity bioassay was used in three experiments to evaluate drinking water concentrates for suitability in multigenerational studies. First, chlorinated water was concentrated 135 fold by reverse osmosis; select lost disinfection by-products were spiked back. Conc...

  9. Developmental Toxicity Evaluations of Whole Mixtures of Disinfection By-products using Concentrated Drinking Water in Rats: Gestational and Lactational Effects of Sulfate and Sodium

    EPA Science Inventory

    A developmental toxicity bioassay was used in three experiments to evaluate drinking water concentrates for suitability in multigenerational studies. First, chlorinated water was concentrated 135 fold by reverse osmosis; select lost disinfection by-products were spiked back. Co...

  10. Application of ultrasound and quartz sand for the removal of disinfection byproducts from drinking water.

    PubMed

    Yang, Wu; Dong, Lili; Luo, Zhen; Cui, Xiaochun; Liu, Jiancong; Liu, Zhongmou; Huo, Mingxin

    2014-04-01

    To the best of our knowledge, little information is available on the combined use of ultrasound (US) and quartz sand (QS) in the removal of disinfection byproducts (DBPs) from drinking water. This study investigates the removal efficiency for 12 DBPs from drinking water by 20 kHz sonolytic treatment, QS adsorption, and their combination. Results indicate that DBPs with logKow≤1.12 could not be sonolysized; for logKow≥1.97, more than 20% removal efficiency was observed, but the removal efficiency was unrelated to logKow. DBPs containing a nitro group are more sensitive to US than those that comprise nitrile, hydrogen, and hydroxyl groups. Among the 12 investigated DBPs, 9 could be adsorbed by QS adsorption. The adsorption efficiency ranged from 12% for 1,1-dichloro-2-propanone to 80% for trichloroacetonitrile. A synergistic effect was found between the US and QS on DBPs removal, and all the 12 DBPs could be effectively removed by the combined use of US and QS. In the presence of US, part of the QS particles were corroded into small particles which play a role in increasing the number of cavitation bubbles and reducing cavitation bubble size and then improve the removal efficiency of DBPs. On the other hand, the presence of US enhances the DBP mass transfer rate to cavitation bubbles and quartz sand. In addition, sonolytic treatment led to a slight decrease of pH, and TOC values decreased under all the three treatment processes.

  11. Identifying Carcinogenic Potentials of Drinking Water Disinfection Byproducts using Normal Human Colonocyte Cultures

    EPA Science Inventory

    Epidemiological studies have linked the consumption of disinfected surface waters to an increased risk of colorectal cancer. Approximately 600 byproducts (DBPs) have been identified for the major disinfectants currently in use and represent less than half of the total organic car...

  12. Enhanced formation of disinfection byproducts in shale gas wastewater-impacted drinking water supplies.

    PubMed

    Parker, Kimberly M; Zeng, Teng; Harkness, Jennifer; Vengosh, Avner; Mitch, William A

    2014-10-01

    The disposal and leaks of hydraulic fracturing wastewater (HFW) to the environment pose human health risks. Since HFW is typically characterized by elevated salinity, concerns have been raised whether the high bromide and iodide in HFW may promote the formation of disinfection byproducts (DBPs) and alter their speciation to more toxic brominated and iodinated analogues. This study evaluated the minimum volume percentage of two Marcellus Shale and one Fayetteville Shale HFWs diluted by fresh water collected from the Ohio and Allegheny Rivers that would generate and/or alter the formation and speciation of DBPs following chlorination, chloramination, and ozonation treatments of the blended solutions. During chlorination, dilutions as low as 0.01% HFW altered the speciation toward formation of brominated and iodinated trihalomethanes (THMs) and brominated haloacetonitriles (HANs), and dilutions as low as 0.03% increased the overall formation of both compound classes. The increase in bromide concentration associated with 0.01-0.03% contribution of Marcellus HFW (a range of 70-200 μg/L for HFW with bromide = 600 mg/L) mimics the increased bromide levels observed in western Pennsylvanian surface waters following the Marcellus Shale gas production boom. Chloramination reduced HAN and regulated THM formation; however, iodinated trihalomethane formation was observed at lower pH. For municipal wastewater-impacted river water, the presence of 0.1% HFW increased the formation of N-nitrosodimethylamine (NDMA) during chloramination, particularly for the high iodide (54 ppm) Fayetteville Shale HFW. Finally, ozonation of 0.01-0.03% HFW-impacted river water resulted in significant increases in bromate formation. The results suggest that total elimination of HFW discharge and/or installation of halide-specific removal techniques in centralized brine treatment facilities may be a better strategy to mitigate impacts on downstream drinking water treatment plants than altering

  13. Enhanced formation of disinfection byproducts in shale gas wastewater-impacted drinking water supplies.

    PubMed

    Parker, Kimberly M; Zeng, Teng; Harkness, Jennifer; Vengosh, Avner; Mitch, William A

    2014-10-01

    The disposal and leaks of hydraulic fracturing wastewater (HFW) to the environment pose human health risks. Since HFW is typically characterized by elevated salinity, concerns have been raised whether the high bromide and iodide in HFW may promote the formation of disinfection byproducts (DBPs) and alter their speciation to more toxic brominated and iodinated analogues. This study evaluated the minimum volume percentage of two Marcellus Shale and one Fayetteville Shale HFWs diluted by fresh water collected from the Ohio and Allegheny Rivers that would generate and/or alter the formation and speciation of DBPs following chlorination, chloramination, and ozonation treatments of the blended solutions. During chlorination, dilutions as low as 0.01% HFW altered the speciation toward formation of brominated and iodinated trihalomethanes (THMs) and brominated haloacetonitriles (HANs), and dilutions as low as 0.03% increased the overall formation of both compound classes. The increase in bromide concentration associated with 0.01-0.03% contribution of Marcellus HFW (a range of 70-200 μg/L for HFW with bromide = 600 mg/L) mimics the increased bromide levels observed in western Pennsylvanian surface waters following the Marcellus Shale gas production boom. Chloramination reduced HAN and regulated THM formation; however, iodinated trihalomethane formation was observed at lower pH. For municipal wastewater-impacted river water, the presence of 0.1% HFW increased the formation of N-nitrosodimethylamine (NDMA) during chloramination, particularly for the high iodide (54 ppm) Fayetteville Shale HFW. Finally, ozonation of 0.01-0.03% HFW-impacted river water resulted in significant increases in bromate formation. The results suggest that total elimination of HFW discharge and/or installation of halide-specific removal techniques in centralized brine treatment facilities may be a better strategy to mitigate impacts on downstream drinking water treatment plants than altering

  14. Reproductive and developmental effects of disinfection by-products in drinking water.

    PubMed

    Reif, J S; Hatch, M C; Bracken, M; Holmes, L B; Schwetz, B A; Singer, P C

    1996-10-01

    Recent epidemiologic studies have reported associations between the consumption of chlorinated drinking water and reproductive and developmental effects. Here we review the available epidemiologic data, assess the hazard potential posed by exposure to disinfection by-products, identify critical data gaps, and offer recommendations for further research. The epidemiologic evidence supporting associations between exposure to water disinfection by-products (DBPs) and adverse pregnancy outcomes is sparse, and positive findings should be interpreted cautiously. The methods used during the early stages of research in this area have been diverse. Variability in exposure assessment and endpoints makes it difficult to synthesize or combine the available data. Exposure misclassification and unmeasured confounding may have lead to bias in risk estimation. Future studies of reproductive outcome and exposure to chlorinated water should use improved methods for exposure assessment to 1) assure selection of appropriate exposure markers, 2) assess seasonal and annual fluctuations in DBPs, 3) assess variability within the distribution system, and 4) assess exposure through multiple routes such as bathing and showering, as well as consumption. Population-based studies should be conducted to evaluate male and female fertility, conception delay, growth retardation, and specific birth defects. The reproductive and developmental effects of exposure to DBPs could be efficiently explored in ongoing investigations by incorporating valid exposure markers and relevant questionnaire information. Future studies should make use of naturally occurring variability in the concentrations of DBPs and may incorporate biomarkers of exposure and effect in their design. Epidemiologic investigations should be conducted in parallel with laboratory-based and animal studies in a coordinated, multidisciplinary approach.

  15. Reproductive and developmental effects of disinfection by-products in drinking water.

    PubMed Central

    Reif, J S; Hatch, M C; Bracken, M; Holmes, L B; Schwetz, B A; Singer, P C

    1996-01-01

    Recent epidemiologic studies have reported associations between the consumption of chlorinated drinking water and reproductive and developmental effects. Here we review the available epidemiologic data, assess the hazard potential posed by exposure to disinfection by-products, identify critical data gaps, and offer recommendations for further research. The epidemiologic evidence supporting associations between exposure to water disinfection by-products (DBPs) and adverse pregnancy outcomes is sparse, and positive findings should be interpreted cautiously. The methods used during the early stages of research in this area have been diverse. Variability in exposure assessment and endpoints makes it difficult to synthesize or combine the available data. Exposure misclassification and unmeasured confounding may have lead to bias in risk estimation. Future studies of reproductive outcome and exposure to chlorinated water should use improved methods for exposure assessment to 1) assure selection of appropriate exposure markers, 2) assess seasonal and annual fluctuations in DBPs, 3) assess variability within the distribution system, and 4) assess exposure through multiple routes such as bathing and showering, as well as consumption. Population-based studies should be conducted to evaluate male and female fertility, conception delay, growth retardation, and specific birth defects. The reproductive and developmental effects of exposure to DBPs could be efficiently explored in ongoing investigations by incorporating valid exposure markers and relevant questionnaire information. Future studies should make use of naturally occurring variability in the concentrations of DBPs and may incorporate biomarkers of exposure and effect in their design. Epidemiologic investigations should be conducted in parallel with laboratory-based and animal studies in a coordinated, multidisciplinary approach. PMID:8930546

  16. Monohaloacetic acid drinking water disinfection by-products inhibit follicle growth and steroidogenesis in mouse ovarian antral follicles in vitro.

    PubMed

    Jeong, Clara H; Gao, Liying; Dettro, Tyler; Wagner, Elizabeth D; Ricke, William A; Plewa, Michael J; Flaws, Jodi A

    2016-07-01

    Water disinfection greatly reduced the incidence of waterborne diseases, but the reaction between disinfectants and natural organic matter in water leads to the formation of drinking water disinfection by-products (DBPs). DBPs have been shown to be toxic, but their effects on the ovary are not well defined. This study tested the hypothesis that monohalogenated DBPs (chloroacetic acid, CAA; bromoacetic acid, BAA; iodoacetic acid, IAA) inhibit antral follicle growth and steroidogenesis in mouse ovarian follicles. Antral follicles were isolated and cultured with either vehicle or DBPs (0.25-1.00mM of CAA; 2-15μM of BAA or IAA) for 48 and 96h. Follicle growth was measured every 24h and the media were analyzed for estradiol levels at 96h. Exposure to DBPs significantly inhibited antral follicle growth and reduced estradiol levels compared to controls. These data demonstrate that DBP exposure caused ovarian toxicity in vitro. PMID:27151372

  17. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters.

    PubMed

    Regli, Stig; Chen, Jimmy; Messner, Michael; Elovitz, Michael S; Letkiewicz, Frank J; Pegram, Rex A; Pepping, T J; Richardson, Susan D; Wright, J Michael

    2015-11-17

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired power plants, conventional oil and gas extraction, textile mills, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. We estimate bladder cancer risk from potential increased bromide levels in source waters of disinfecting public drinking water systems in the United States. Bladder cancer is the health end point used by the United States Environmental Protection Agency (EPA) in its benefits analysis for regulating disinfection byproducts in drinking water. We use estimated increases in the mass of the four regulated trihalomethanes (THM4) concentrations (due to increased bromide incorporation) as the surrogate disinfection byproduct (DBP) occurrence metric for informing potential bladder cancer risk. We estimate potential increased excess lifetime bladder cancer risk as a function of increased source water bromide levels. Results based on data from 201 drinking water treatment plants indicate that a bromide increase of 50 μg/L could result in a potential increase of between 10(-3) and 10(-4) excess lifetime bladder cancer risk in populations served by roughly 90% of these plants. PMID:26489011

  18. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters.

    PubMed

    Regli, Stig; Chen, Jimmy; Messner, Michael; Elovitz, Michael S; Letkiewicz, Frank J; Pegram, Rex A; Pepping, T J; Richardson, Susan D; Wright, J Michael

    2015-11-17

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired power plants, conventional oil and gas extraction, textile mills, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. We estimate bladder cancer risk from potential increased bromide levels in source waters of disinfecting public drinking water systems in the United States. Bladder cancer is the health end point used by the United States Environmental Protection Agency (EPA) in its benefits analysis for regulating disinfection byproducts in drinking water. We use estimated increases in the mass of the four regulated trihalomethanes (THM4) concentrations (due to increased bromide incorporation) as the surrogate disinfection byproduct (DBP) occurrence metric for informing potential bladder cancer risk. We estimate potential increased excess lifetime bladder cancer risk as a function of increased source water bromide levels. Results based on data from 201 drinking water treatment plants indicate that a bromide increase of 50 μg/L could result in a potential increase of between 10(-3) and 10(-4) excess lifetime bladder cancer risk in populations served by roughly 90% of these plants.

  19. Characterization of soluble microbial products as precursors of disinfection byproducts in drinking water supply.

    PubMed

    Liu, Jin-Lin; Li, Xiao-Yan; Xie, Yue-Feng; Tang, Hao

    2014-02-15

    Water pollution by wastewater discharge can cause the problem of disinfection byproducts (DBPs) in drinking water supply. In this study, DBP formation characteristics of soluble microbial products (SMPs) as the main products of wastewater organic biodegradation were investigated. The results show that SMPs can act as DBP precursors in simulated wastewater biodegradation process. Under the experimental conditions, stabilized SMPs had DBPFP (DBP formation potential) yield of around 5.6 μmol mmol(-1)-DOC (dissolved organic carbon) and DBP speciation profile different from that of the conventional precursor, natural organic matter (NOM). SMPs contained polysaccharides, proteins, and humic-like substances, and the latter two groups can act as reactive DBP precursors. SMP fraction with molecular weight of <1 kDa accounted for 85% of the organic carbon and 65% of the DBP formation. As small SMP molecules are more difficult to remove by conventional water treatment processes, more efforts are needed to control wastewater-derived DBP problem in water resource management.

  20. Disinfection characteristics of the dissolved organic fractions at several stages of a conventional drinking water treatment plant in Southern China.

    PubMed

    Zhao, Zhen-Ye; Gu, Ji-Dong; Li, Hai-Bo; Li, Xiao-Yan; Leung, Kenneth Mei-Yee

    2009-12-30

    Dissolved organic matter (DOM) influences many aspects of drinking water treatment, including the formation of harmful disinfection by-products (DBPs) when disinfectants are applied. DOM was isolated and fractionated using membrane ultra-filtration (UF) and reverse osmosis (RO) to eight individual fractions based on molecular weight cut-offs from a conventional surface water treatment plant (WTP) in Guangzhou of PR China. Molecular weights of these eight fractions were further calibrated using high performance size exclusion chromatography (HPSEC) and they ranged from 0.36 to 182.6 kDa. Fractions with molecular weight <0.80 kDa obtained by YC-05 UF membrane and RO were the major ones in all four stages of the water treatment processes; both ZM-500 and YM-100 membranes showed the highest removal efficiency when coupling with conventional coagulation and sedimentation processes. The elemental analysis showed that YC-05 fraction had greater polarity and aromaticity than any of the others. Furthermore, disinfection characteristics and trihalomethane formation potential (THMFP) were determined for all DOM fractions obtained in this study. YC-05 fraction was the major precursor for trihalomethane (THMs) formation among the samples tested and could be removed effectively by particulate activated carbon (PAC) adsorption. RO fraction could not be removed by PAC adsorption and, as a result, consumed more chlorine in the disinfection process. The results suggested that advanced drinking water treatment should focus on the removal of low molecular weight DOM in the source water.

  1. A picture of polar iodinated disinfection byproducts in drinking water by (UPLC/)ESI-tqMS.

    PubMed

    Ding, Guoyu; Zhang, Xiangru

    2009-12-15

    Iodinated disinfection byproducts (DBPs) are generally more toxic than their chlorinated and brominated analogues. Up to date, only a few iodinated DBPs in drinking water have been identified by gas chromatography/mass spectrometry. In this work, a method for fast selective detection of polar iodinated DBPs was developed using an electrospray ionization-triple quadrupole mass spectrometer (ESI-tqMS) by conducting precursor ion scan of iodide at m/z 126.9. With such a method, pictures of polar iodinated DBPs in chlorinated, chloraminated, and chlorine-ammonia treated water samples were achieved. By coupling state-of-the-art ultra performance liquid chromatography (UPLC) to the ESI-tqMS, structures of 17 iodinated DBPs were tentatively proposed. The results fully demonstrate that, with respect to the DBP number/levels among the three disinfection processes, chloramination generally generated the most/highest iodinated DBPs, chlorination generally produced the fewest/lowest iodinated DBPs, and chlorine-ammonia sequential treatment formed iodinated DBPs lying in between; the numbers of iodinated DBPs in chloraminated Suwannee River Fulvic Acid (SRFA) and Humic Acid (SRHA) were nearly the same, but the levels of aliphatic iodinated DBPs were higher in the chloraminated SRFA while the levels of aromatic iodinated DBPs were higher in the chloraminated SRHA; a couple of nitrogenous iodinated DBPs were found in chloramination and chlorine-ammonia treatment. The ratio of total organic iodine levels in chlorine-ammonia sequential treatment and chloramination could be expressed as a function of the lag time of ammonia addition.

  2. Toxicity of drinking water disinfection byproducts: cell cycle alterations induced by the monohaloacetonitriles.

    PubMed

    Komaki, Yukako; Mariñas, Benito J; Plewa, Michael J

    2014-10-01

    Haloacetonitriles (HANs) are a chemical class of drinking water disinfection byproducts (DBPs) that form from reactions between disinfectants and nitrogen-containing precursors, the latter more prevalent in water sources impacted by algae bloom and municipal wastewater effluent discharge. HANs, previously demonstrated to be genotoxic, were investigated for their effects on the mammalian cell cycle. Treating Chinese hamster ovary (CHO) cells with monoHANs followed by the release from the chemical treatment resulted in the accumulation of abnormally high DNA content in cells over time (hyperploid). The potency for the cell cycle alteration followed the order: iodoacetonitrile (IAN) > bromoacetonitrile (BAN) ≫ chloroacetonitrile (CAN). Exposure to 6 μM IAN, 12 μM BAN and 900 μM CAN after 26 h post-treatment incubation resulted in DNA repair; however, subsequent cell cycle alteration effects were observed. Cell proliferation of HAN-treated cells was suppressed for as long as 43 to 52 h. Enlarged cell size was observed after 52 h post-treatment incubation without the induction of cytotoxicity. The HAN-mediated cell cycle alteration was mitosis- and proliferation-dependent, which suggests that HAN treatment induced mitosis override, and that HAN-treated cells proceeded into S phase and directly into the next cell cycle. Cells with multiples genomes would result in aneuploidy (state of abnormal chromosome number and DNA content) at the next mitosis since extra centrosomes could compromise the assembly of bipolar spindles. There is accumulating evidence of a transient tetraploid state proceeding to aneuploidy in cancer progression. Biological self-defense systems to ensure genomic stability and to eliminate tetraploid cells exist in eukaryotic cells. A key tumor suppressor gene, p53, is oftentimes mutated in various types of human cancer. It is possible that HAN disruption of the normal cell cycle and the generation of aberrant cells with an abnormal number of

  3. Occurrence and formation of chloro- and bromo-benzoquinones during drinking water disinfection.

    PubMed

    Zhao, Yuli; Anichina, Janna; Lu, Xiufen; Bull, Richard J; Krasner, Stuart W; Hrudey, Steve E; Li, Xing-Fang

    2012-09-15

    Consumption of chlorinated drinking water has shown somewhat consistent association with increased risk of bladder cancer in a series of epidemiological studies, but plausible causative agents have not been identified. Halobenzoquinones (HBQs) have been recently predicted as putative disinfection byproducts (DBPs) that might be of toxicological relevance. This study reports the occurrence frequencies and concentrations of HBQs in plant effluents from nine drinking water treatment plants in the USA and Canada, where four common disinfection methods, chlorination, chloramination, chlorination with chloramination, and ozonation with chloramination, are used. In total, 16 water samples were collected and analyzed for eight HBQs: 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (2,6-DC-3-MBQ), 2,3,6-trichloro-1,4-benzoquinone (2,3,6-TriCBQ), 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,3-dibromo-5,6-dimethyl-1,4-benzoquinone (2,3-DB-5,6-DM-BQ), tetrabromo-1,4-benzoquinone (TetraB-1,4-BQ), and tetrabromo-1,2-benzoquinone (TetraB-1,2-BQ). Of these, 2,6-DCBQ, 2,6-DBBQ, 2,6-DC-3-MBQ and 2,3,6-TriCBQ were detected in 16, 11, 6, and 3 of the 16 samples with the method detection limit (DL) of 1.0, 0.5, 0.9 and 1.5 ng/L, respectively, using a solid phase extraction and high performance liquid chromatography-tandem mass spectrometry method. The concentrations were in the ranges of 4.5-274.5 ng/L for 2,6-DCBQ, below DL to 37.9 ng/L for 2,6-DBBQ, below DL to 6.5 ng/L for 2,6-DC-3-MBQ, and below DL to 9.1 ng/L for 2,3,6-TriCBQ. These authentic samples show DCBQ and DBBQ as the most abundant and frequently detectable HBQs. In addition, laboratory controlled experiments were performed to examine the formation of HBQs and their subsequent stability toward hydrolysis when the disinfectants, chlorine, chloramine, or ozone followed by chloramines, reacted with phenol (a known precursor) under various conditions

  4. Chemistry, Toxicity and Health Risk Assessment of Drinking Water Disinfection ByProducts

    EPA Science Inventory

    Disinfection byproducts (DBPs) are formed by the reaction of oxidizing chemicals (such as chlorine, ozone and chloramines) used to control waterborne pathogens with natural organic material and other substances in water. DBP mixture composition varies as a function of geographic ...

  5. Component-Based and Whole-Mixture Techniques for Addressing the Toxicity Of Drinking-Water Disinfection By-Product Mixtures

    EPA Science Inventory

    To conduct the health-effect studies described in subsequent articles, concentrated aqueous mixtures of disinfection byproducts were required for the two separate treatment trains described in the preceding article. To accomplish this, the finished drinking waters from each trea...

  6. INFLUENCE OF THE DRINKING WATER DISINFECTION BY-PRODUCT DIBROMOACETIC ACID ON RAT ESTROUS CYCLICITY AND OVARIAN FOLLICULAR STEROID RELEASE IN VITRO

    EPA Science Inventory

    The drinking water disinfection by-product, dibromoacetic acid (DBA) has been reported to affect gonadal functions in the male rat. However, there is little information regarding its influence on female reproductive activity. Consequently, the present study investigated the eff...

  7. Occurrence, Synthesis and Mammalian Cell Cytotoxicity and Genotoxicity of Haloacetamides: An Emerging Class of Nitrogenous Drinking Water Disinfection By-Products

    EPA Science Inventory

    The haloacetamides, a class of emerging nitrogenous drinking water disinfection by-products (DBPs), were analyzed for their chronic cytotoxicity and for the induction of genomic DNA damage in Chinese hamster ovary cells.

  8. DIBROMOACETIC ACID, A PREVALENT BY-PRODUCT OF DRINKING WATER DISINFECTION, COMPROMISES THE SYNTHESIS OF SPECIFIC SEMINFEROUS TUBULE PROTEINS FOLLOWING BOTH IN VIVO AND IN VITRO EXPOSURES

    EPA Science Inventory

    ABSTRACT
    Dibromoacetic acid(DBA) is a byproduct of drinking water disinfection that alters spermatogenesis in adult male rats. To identify a mechanism by which DBA alters spermatogenesis, seminiferous tubules representing specific groups of spermatogenic stages were expos...

  9. Analysis of oxyhalide disinfection by-products and other anions of interest in drinking water by ion chromatography.

    PubMed

    Hautman, D P; Bolyard, M

    1992-06-01

    The US Environmental Protection Agency is developing regulations for various drinking water disinfection by-products (DBPs). This effort involves developing analytical methods for the DBPs formed as a result of different disinfection treatments and collecting occurrence data for these species. Ion chromatography is one method being used to analyze drinking water samples for the following inorganic DBPs: chlorite, chlorate and bromate. These anions, however, are difficult to separate from common interfering anions of chloride, carbonate and nitrate. A method is therefore presented by which tetraborate/boric acid is used to separate these anions. Method detection limits of the order of 10 micrograms/l, using conductivity and UV detection were obtained. Stability studies of chlorite showing the effectiveness of ethylenediamine as a preservative and summary data for an occurrence of nitrite, nitrate and the DBP precursor bromide are presented.

  10. Determinants of disinfectant pretreatment efficacy for nitrosamine control in chloraminated drinking water.

    PubMed

    McCurry, Daniel L; Krasner, Stuart W; von Gunten, Urs; Mitch, William A

    2015-11-01

    Utilities using chloramines need strategies to mitigate nitrosamine formation to meet potential future nitrosamine regulations. The ability to reduce NDMA formation under typical post-chloramination conditions of pretreatment with ultraviolet light from a low pressure mercury lamp (LPUV), free chlorine (HOCl), ozone (O3), and UV light from a medium pressure mercury lamp (MPUV) were compared at exposures relevant to drinking water treatment. The order of efficacy after application to waters impacted by upstream wastewater discharges was O3 > HOCl ≈ MPUV > LPUV. NDMA precursor abatement generally did not correlate well between oxidants, and waters exhibited different behaviors with respect to pH and temperature, suggesting a variety of source-dependent NDMA precursors. For wastewater-impacted waters, the observed pH dependence for precursor abatement suggested the important role of secondary or tertiary amine precursors. Although hydroxyl radicals did not appear to be important for NDMA precursor abatement during O3 or MPUV pretreatment, the efficacy of MPUV correlated strongly with dissolved organic carbon concentration (p = 0.01), suggesting alternative indirect photochemical pathways. The temperature dependences during pre- and post-disinfection indicated that NDMA formation is likely to increase during warm seasons for O3 pretreatment, decrease for HOCl pretreatment, and remain unchanged for MPUV treatment, although seasonal changes in source water quality may counteract the temperature effects. For two waters impacted by relatively high polyDADMAC coagulant doses, pretreatment with HOCl, O3, and MPUV increased NDMA formation during post-chloramination. For O3 pretreatment, hydroxyl radicals likely led to precursor formation from the polymer in the latter tests. MPUV treatment of polymer-impacted water increased subsequent NDMA formation through an indirect photochemical process. Many factors may mitigate the importance of this increased NDMA formation

  11. Assessment of reproductive effects on complex mixtures of disinfection by-products in a multigenerational rat bioassay of drinking water concentrates

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  12. Assessment of Reproductive Effects of Complex Mixtures of Disinfection By-Products in a Multi-Generational Rat Bioassay of Drinking Water Concentrates - Monterey

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  13. Solar radiation disinfection of drinking water at temperate latitudes: inactivation rates for an optimised reactor configuration.

    PubMed

    Davies, C M; Roser, D J; Feitz, A J; Ashbolt, N J

    2009-02-01

    Solar radiation-driven inactivation of bacteria, virus and protozoan pathogen models was quantified in simulated drinking water at a temperate latitude (34 degrees S). The water was seeded with Enterococcus faecalis, Clostridium sporogenes spores, and P22 bacteriophage, each at ca 1x10(5) mL(-1), and exposed to natural sunlight in 30-L reaction vessels. Water temperature ranged from 17 to 39 degrees C during the experiments lasting up to 6h. Dark controls showed little inactivation and so it was concluded that the inactivation observed was primarily driven by non-thermal processes. The optimised reactor design achieved S90 values (cumulative exposure required for 90% reduction) for the test microorganisms in the range 0.63-1.82 MJ m(-2) of Global Solar Exposure (GSX) without the need for TiO2 as a catalyst. High turbidity (840-920 NTU) only reduced the S(90) value by <40%. Further, when all S90 means were compared this decrease was not statistically significant (prob.>0.05). However, inactivation was significantly reduced for E. faecalis and P22 when the transmittance of UV wavelengths was attenuated by water with high colour (140 PtCo units) or a suboptimally transparent reactor lid (prob.<0.05). S90 values were consistent with those measured by other researchers (ca 1-10 MJ m(-2)) for a range of waters and microorganisms. Although temperatures required for SODIS type pasteurization were not produced, non-thermal inactivation alone appeared to offer a viable means for reliably disinfecting low colour source waters by greater than 4 orders of magnitude on sunny days at 34 degrees S latitude.

  14. IODO-ACID DISINFECTION BY-PRODUCTS IN DRINKING WATER: DOES LC/ESI-MS/MS OFFER AN ADVANTAGE OVER GC/NCI-MS?

    EPA Science Inventory

    As part of a recent Nationwide Disinfection By-Product (DBP) Occurrence Study, iodo-acids were identified for the first time as DBPs in drinking water disinfected with chloramines. The iodo-acids identified included iodoacetic acid, bromoiodoacetic acid, (E)-3-bromo-3-iodo-prope...

  15. OXIDATIVE DNA DAMAGE FROM POTASSIUM BROMATE EXPOSURE IN LONG-EVANS RATS IS NOT ENHANCED BY A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Public drinking water treated with chemical disinfectants contains a complex mixture of disinfection by-products (DBPs) for which the relative toxicity of the mixtures needs to be characterized to accurately assess risk. Potassium bromate (KBrO3) is a by-product from ozonation of...

  16. Glutathione-Mediated Detoxification of Halobenzoquinone Drinking Water Disinfection Byproducts in T24 Cells

    PubMed Central

    Li, Jinhua; Wang, Wei; Zhang, Hongquan; Le, X. Chris; Li, Xing-Fang

    2014-01-01

    Halobenzoquinones (HBQs) are a new class of drinking water disinfection byproducts (DBPs) and are capable of producing reactive oxygen species and causing oxidative damage to proteins and DNA in T24 human bladder carcinoma cells. However, the exact mechanism of the cytotoxicity of HBQs is unknown. Here, we investigated the role of glutathione (GSH) and GSH-related enzymes including glutathione S-transferase (GST) and glutathione peroxidase (GPx) in defense against HBQ-induced cytotoxicity in T24 cells. The HBQs are 2,6-dichloro-1,4-benzoquinone (DCBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), 2,3,6-trichloro-1,4-benzoquinone (TriCBQ), and 2,6-dibromobenzoquinone (DBBQ). We found that depletion of cellular GSH could sensitize cells to HBQs and extracellular GSH supplementation could attenuate HBQ-induced cytotoxicity. HBQs caused significant cellular GSH depletion and increased cellular GST activities in a concentration-dependent manner. Our mass spectrometry study confirms that HBQs can conjugate with GSH, explaining in part the mechanism of GSH depletion by HBQs. The effects of HBQs on GPx activity are compound dependent; DCMBQ and DBBQ decrease cellular GPx activities, whereas DCBQ and TriCBQ have no significant effects. Pearson correlation analysis shows that the cellular GSH level is inversely correlated with ROS production and cellular GST activity in HBQ-treated cells. These results support a GSH and GSH-related enzyme-mediated detoxification mechanism of HBQs in T24 cells. PMID:24812012

  17. An electrospray ionization-tandem mass spectrometry method for identifying chlorinated drinking water disinfection byproducts.

    PubMed

    Zhang, Xiangru; Minear, Roger A; Guo, Yingbo; Hwang, Cordelia J; Barrett, Sylvia E; Ikeda, Kazuhiro; Shimizu, Yoshihisa; Matsui, Saburo

    2004-11-01

    Identification of chlorinated drinking water disinfection byproducts (DBPs) was investigated by using electrospray ionization-mass spectrometry/mass spectrometry (ESI-MS/MS). Chlorine-containing compounds were found to form chloride ion fragments by MS/MS, which can be used as a 'fingerprint' for chlorinated DBPs. Instrumental parameters that affect the formation of chloride ions by ESI-MS/MS were examined, and appropriate conditions for use in finding specific structural information were evaluated. The results show that maximizing the formation of chloride ions by MS/MS required a relatively high collision energy and collision gas pressure; also, limiting the scan range to m/z 30-40 allowed improved sensitivity for detection; but obtaining structural information required the use of lower collision energies. The conditions obtained were demonstrated to be effective in identifying chlorinated DBPs in a standard sample with relatively low concentrations of each component and in a chlorinated humic substance sample. Sample pretreatment techniques including ultrafiltration and size exclusion chromatography appeared to be helpful for identifying highly polar or high molecular weight chlorine-containing DBPs by ESI-MS/MS.

  18. Glutathione-mediated detoxification of halobenzoquinone drinking water disinfection byproducts in T24 cells.

    PubMed

    Li, Jinhua; Wang, Wei; Zhang, Hongquan; Le, X Chris; Li, Xing-Fang

    2014-10-01

    Halobenzoquinones (HBQs) are a new class of drinking water disinfection byproducts (DBPs) and are capable of producing reactive oxygen species and causing oxidative damage to proteins and DNA in T24 human bladder carcinoma cells. However, the exact mechanism of the cytotoxicity of HBQs is unknown. Here, we investigated the role of glutathione (GSH) and GSH-related enzymes including glutathione S-transferase (GST) and glutathione peroxidase (GPx) in defense against HBQ-induced cytotoxicity in T24 cells. The HBQs are 2,6-dichloro-1,4-benzoquinone (DCBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), 2,3,6-trichloro-1,4-benzoquinone (TriCBQ), and 2,6-dibromobenzoquinone (DBBQ). We found that depletion of cellular GSH could sensitize cells to HBQs and extracellular GSH supplementation could attenuate HBQ-induced cytotoxicity. HBQs caused significant cellular GSH depletion and increased cellular GST activities in a concentration-dependent manner. Our mass spectrometry study confirms that HBQs can conjugate with GSH, explaining in part the mechanism of GSH depletion by HBQs. The effects of HBQs on GPx activity are compound dependent; DCMBQ and DBBQ decrease cellular GPx activities, whereas DCBQ and TriCBQ have no significant effects. Pearson correlation analysis shows that the cellular GSH level is inversely correlated with ROS production and cellular GST activity in HBQ-treated cells. These results support a GSH and GSH-related enzyme-mediated detoxification mechanism of HBQs in T24 cells.

  19. Disinfection efficacy of chlorine and peracetic acid alone or in combination against Aspergillus spp. and Candida albicans in drinking water.

    PubMed

    Sisti, Maurizio; Brandi, Giorgio; De Santi, Mauro; Rinaldi, Laura; Schiavano, Giuditta F

    2012-03-01

    The aim of the present study was to evaluate the fungicidal activity of chlorine and peracetic acid in drinking water against various pathogenic Aspergillus spp. and Candida albicans strains. A. nidulans exhibited the greatest resistance, requiring 10 ppm of chlorine for 30 min contact time for a complete inactivation. Under the same experimental conditions, peracetic acid was even less fungicidal. In this case, A. niger proved to be the most resistant species (50 ppm for 60 min for complete inactivation). All Aspergillus spp. were insensitive to 10 ppm even with extended exposure (>5 h). The combination of chlorine and peracetic acid against Aspergillus spp. did not show synergistic effects except in the case of A. flavus. Complete growth inhibition of C. albicans was observed after about 3 h contact time with 0.2 ppm. C. albicans was less sensitive to peracetic acid. Hence the concentrations of chlorine that are usually present in drinking water distribution systems are ineffective against several Aspergillus spp. and peracetic acid cannot be considered an alternative to chlorine for disinfecting drinking water. The combination of the two biocides is not very effective in eliminating filamentous fungi at the concentrations permitted for drinking water disinfection.

  20. The effect of inorganic precursors on disinfection byproduct formation during UV-chlorine/chloramine drinking water treatment.

    PubMed

    Lyon, Bonnie A; Dotson, Aaron D; Linden, Karl G; Weinberg, Howard S

    2012-10-01

    Ultraviolet (UV) disinfection is being increasingly used in drinking water treatment. It is important to understand how its application to different types of water may influence finished water quality, particularly as anthropogenic activity continues to impact the quality of source waters. The objective of this study was to evaluate the effect of inorganic precursors on the formation of regulated and unregulated disinfection byproducts (DBPs) during UV irradiation of surface waters when combined with chlorination or chloramination. Samples were collected from three drinking water utilities supplied by source waters with varying organic and inorganic precursor content. The filtered samples were treated in the laboratory with a range of UV doses delivered from low pressure (LP, UV output at 253.7 nm) and medium pressure (MP, polychromatic UV output 200-400 nm) mercury lamps followed by chlorination or chloramination, in the presence and absence of additional bromide and nitrate. The regulated trihalomethanes and haloacetic acids were not affected by UV pretreatment at disinfection doses (40-186 mJ/cm²). With higher doses (1000 mJ/cm²), trihalomethane formation was increased 30-40%. While most effects on DBPs were only observed with doses much higher than typically used for UV disinfection, there were some effects on unregulated DBPs at lower doses. In nitrate-spiked samples (1-10 mg N/L), chloropicrin formation doubled and increased three- to six-fold with 40 mJ/cm² MP UV followed by chloramination and chlorination, respectively. Bromopicrin formation was increased in samples containing bromide (0.5-1 mg/L) and nitrate (1-10 mg N/L) when pretreated with LP or MP UV (30-60% with 40 mJ/cm² LP UV and four- to ten-fold increase with 40 mJ/cm² MP UV, after subsequent chlorination). The formation of cyanogen chloride doubled and increased three-fold with MP UV doses of 186 and 1000 mJ/cm², respectively, when followed by chloramination in nitrate-spiked samples but

  1. THE HEALTHY MEN STUDY: A MODEL APPROACH FOR EXAMINING POTENTIAL MALE REPRODUCTIVE HEALTH EFFECTS ASSOCIATED WITH EXPOSURE TO DISINFECTION BYPRODUCTS IN DRINKING WATER.

    EPA Science Inventory

    The Healthy Men Study (HMS) is a prospective multisite community study on drinking water disinfection byproducts (DBPs) and male reproductive health. We are testing whether exposure to DBPs in drinking water may be associated with altered semen quality, a hypothesis derived from...

  2. INTERRELATIONSHIPS AMONG EPIGENETIC MECHANISMS FOR RISK ASSESSMENT OF DICHLOROACETIC ACID, A DRINKING WATER BY-PRODUCT OF THE CHLORINE DISINFECTION PROCESS

    EPA Science Inventory

    The reauthorization of The Safe Drinking Water Act of 1996 requires the EPA to develop a priority list of chemicals that are present in drinking water and to conduct research into the modes and mechanisms of action by which they produce adverse effects. The disinfection by-produc...

  3. Identification and characterization of phenylacetonitrile as a nitrogenous disinfection byproduct derived from chlorination of phenylalanine in drinking water.

    PubMed

    Ma, Xiaoyan; Deng, Jing; Feng, Jiao; Shanaiah, Narasimhamurthy; Smiley, Elizabeth; Dietrich, Andrea M

    2016-10-01

    Unregulated disinfection byproducts (DBPs), including nitrogenous disinfection byproducts (N-DBPs), originating from chlorination of the precursor amino acid phenylalanine in aqueous systems, were identified in laboratory reactions and distributed tap. The major N-DBP identified was phenylacetonitrile, and minor DBPs of benzyl chloride, phenylacetaldehyde, 2-chlorobenzyl cyanide, and 2, 6-diphenylpyridine were also formed. Phenylacetonitrile was generated through decarboxylation, dechlorination and/or hydrolysis processes. With an aromatic structure, phenylacetonitrile has an unpleasant odor of various descriptors and an odor threshold concentration of 0.2 ppt-v as measured through gas chromatography-olfactometry. The half-life of phenylacetonitrile in reagent water and chlorinated water at 19 °C were 121 h and 792 h, respectively. The occurrence of phenylacetonitrile as an N-DBP in tap water was investigated for the first time; the results revealed that μg/L concentrations were present in nine different distributed drinking waters in China and the United States. Phenylacetonitrile deteriorates the aesthetic quality of drinking water and may present risk due to its prolonged existence in drinking water, especially in the presence of residual chlorine.

  4. A Summary of Publications on the Development of Mode-of-Action Information and Statistical Tools for Evaluating Health Outcomes from Drinking Water Disinfection By-Product (DBP) Exposures

    EPA Science Inventory

    Chemical contaminants are formed as a consequence of chemical disinfection of public drinking waters. Chemical disinfectants, which are used to kill harmful microorganisms, react with natural organic matter (NOM), bromide, iodide, and other compounds, forming complex mixtures...

  5. Silver nanoparticle-alginate composite beads for point-of-use drinking water disinfection.

    PubMed

    Lin, Shihong; Huang, Rixiang; Cheng, Yingwen; Liu, Jie; Lau, Boris L T; Wiesner, Mark R

    2013-08-01

    Silver nanoparticles (AgNPs)-alginate composite beads were synthesized using three different approaches as filler materials of packed columns for simultaneous filtration-disinfection as an alternative portable water treatment process. The prepared composite beads were packed into a column through which Escherichia coli containing water was filtered to evaluate the disinfection efficacy. Excellent disinfection performance (no detectable viable colony) was achieved with a hydraulic retention time (HRT) as short as 1 min (the shortest tested) with the SGR (Simultaneous-Gelation-Reduction) and AR (Adsorption-Reduction) beads that were prepared using in situ reduction of Ag(+). Comparatively, the SGR beads released significantly less Ag(+)/AgNPs than the AR beads did within the same HRT. From the results of this study it was identified that SGR may be the best choice among all three different synthesis approaches in that the SGR beads can achieve satisfactory bactericidal performance with a relatively low material consumption rate.

  6. Genotoxic and clastogenic effects of monohaloacetic acid drinking water disinfection by-products in primary human lymphocytes.

    PubMed

    Escobar-Hoyos, Luisa F; Hoyos-Giraldo, Luz Stella; Londoño-Velasco, Elizabeth; Reyes-Carvajal, Ingrid; Saavedra-Trujillo, Diana; Carvajal-Varona, Silvio; Sánchez-Gómez, Adalberto; Wagner, Elizabeth D; Plewa, Michael J

    2013-06-15

    The haloacetic acids (HAAs) are the second-most prevalent class of drinking water disinfection by-products formed by chemical disinfectants. Previous studies have determined DNA damage and repair of HAA-induced lesions in mammalian and human cell lines; however, little is known of the genomic DNA and chromosome damage induced by these compounds in primary human cells. The aim of this study was to evaluate the genotoxic and clastogenic effects of the monoHAA disinfection by-products in primary human lymphocytes. All monoHAAs were genotoxic in primary human lymphocytes, the rank order of genotoxicity and cytotoxicity was IAA > BAA > CAA. After 6 h of repair time, only 50% of the DNA damage (maximum decrease in DNA damage) was repaired compared to the control. This demonstrates that primary human lymphocytes are less efficient in repairing the induced damage by monoHAAs than previous studies with mammalian cell lines. In addition, the monoHAAs induced an increase in the chromosome aberration frequency as a measurement of the clastogenic effect of these compounds. These results coupled with genomic technologies in primary human cells and other mammalian non-cancerous cell lines may lead to the identification of biomarkers that may be employed in feedback loops to aid water chemists and engineers in the overall goal of producing safer drinking water.

  7. Formation of brominated disinfection byproducts during Chloramination of drinking water: new polar species and overall kinetics.

    PubMed

    Zhai, Hongyan; Zhang, Xiangru; Zhu, Xiaohu; Liu, Jiaqi; Ji, Min

    2014-01-01

    The formation of brominated disinfection byproducts (Br-DBPs), which are generally significantly more cytotoxic and genotoxic than their chlorinated analogues, in chloramination has not been fully examined. In this work, the formation of new polar Br-DBPs in simulated drinking waters was examined using state-of-the-art ultraperformance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry. As many as 29 aliphatic, aromatic, or nitrogenous polar Br-DBPs were detected in chloramination, and five of them (including 2,4,6-tribromoresorcinol, 2,6-dibromo-4-nitrophenol, 2,2,4-tribromo-5-hydroxy-4-cyclopentene-1,3-dione, 2,2,4-dibromochloro-5-hydroxy-4-cyclopentene-1,3-dione, and 2,2,4-bromodichloro-5-hydroxy-4-cyclopentene-1,3-dione) were tentatively identified. Unlike chlorination, chloramination favored the formation of aromatic and nitrogenous polar Br-DBPs and was mild enough to allow polar intermediate Br-DBPs to accumulate. To further explore the formation mechanism of Br-DBPs in chloramination, a quantitative empirical model involving 33 major reactions was developed to describe the overall kinetics. According to the modeling results, bromochloramine and monobromamine were the major species responsible for 54.2-58.1% and 41.7-45.7%, respectively, of the formed Br-DBPs, while hypobromous acid accounted for only 0.2% of the formed Br-DBPs; direct reactions between monochloramine and natural organic matter accounted for the majority of the formed chlorinated DBPs (93.7-95.1%); hypochlorous acid and hypobromous acid in the chloramination were at ng/L or subng/L levels, which were not enough to cause polar intermediate Br-DBPs to decompose.

  8. INTEGRATED TECHNOLOGY-BASED TOXICOLOGY STUDIES ON DRINKING WATER DISINFECTION BYPRODUCTS (DBPS)

    EPA Science Inventory

    DBPs are formed by reactions of chemical disinfectants with natural organic matter in the source water. Although more than 300 DBPs are known, many remain unidentified; for chlorination, known DBPs account for ~50% of the mass of total organic halide. Toxicological evaluation o...

  9. Non-PRASA Drinking Water Research on UV Disinfection in Puerto Rico

    EPA Science Inventory

    The U.S. EPA and InterAmerican University of San German worked with water treatment operators from Patillas, Puerto Rico on the installation, training and testing of pretreatment/UV disinfection systems in the communities of La Sofia and Apeadero. This presentation provides path...

  10. Disinfection of drinking water contaminated with Cryptosporidium parvum oocysts under natural sunlight and using the photocatalyst TiO2.

    PubMed

    Méndez-Hermida, Fernando; Ares-Mazás, Elvira; McGuigan, Kevin G; Boyle, Maria; Sichel, Cosima; Fernández-Ibáñez, Pilar

    2007-09-25

    The results of a batch-process solar disinfection (SODIS) and solar photocatalytic disinfection (SPCDIS) on drinking water contaminated with Cryptosporidium are reported. Cryptosporidium parvum oocyst suspensions were exposed to natural sunlight in Southern Spain and the oocyst viability was evaluated using two vital dyes [4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI)]. SODIS exposures (strong sunlight) of 8 and 12h reduced oocyst viability from 98% (+/-1.3%) to 11.7% (+/-0.9%) and 0.3% (+/-0.33%), respectively. SODIS reactors fitted with flexible plastic inserts coated with TiO2 powder (SPCDIS) were found to be more effective than those which were not. After 8 and 16 h of overcast and cloudy solar irradiance conditions, SPCDIS reduced oocyst viability from 98.3% (+/-0.3%) to 37.7% (+/-2.6%) and 11.7% (+/-0.7%), respectively, versus to that achieved using SODIS of 81.3% (+/-1.6%) and 36.0% (+/-1.0%), respectively. These results confirm that solar disinfection of drinking water can be an effective household intervention against Cryptosporidium contamination.

  11. Drinking water biofilms on copper and stainless steel exhibit specific molecular responses towards different disinfection regimes at waterworks.

    PubMed

    Jungfer, Christina; Friedrich, Frank; Varela Villarreal, Jessica; Brändle, Katharina; Gross, Hans-Jürgen; Obst, Ursula; Schwartz, Thomas

    2013-09-01

    Biofilms growing on copper and stainless steel substrata in natural drinking water were investigated. A modular pilot-scale distribution facility was installed at four waterworks using different raw waters and disinfection regimes. Three-month-old biofilms were analysed using molecular biology and microscopy methods. High total cell numbers, low counts of actively respiring cells and low numbers of cultivable bacteria indicated the high abundance of viable but not cultivable bacteria in the biofilms. The expression of the recA SOS responsive gene was detected and underlined the presence of transcriptionally active bacteria within the biofilms. This effect was most evident after UV disinfection, UV oxidation and UV disinfection with increased turbidity at waterworks compared to chemically treated and non-disinfected systems. Furthermore, live/dead staining techniques and environmental scanning electron microscopy imaging revealed the presence of living and intact bacteria in biofilms on copper substrata. Cluster analyses of DGGE profiles demonstrated differences in the composition of biofilms on copper and steel materials.

  12. Use of reflectors to enhance the synergistic effects of solar heating and solar wavelengths to disinfect drinking water sources.

    PubMed

    Rijal, G K; Fujioka, R S

    2003-01-01

    Aluminum reflectors were added to solar units designed to inactivate faecal microorganisms (faecal coliform, E. coli, enterococci, FRNA coliphage, C. perfringens) in stream water and diluted sewage by the two mechanisms (solar heat, solar UV) known to inactivate microorganisms. During sunny conditions, solar units with and without reflectors inactivated E. coli to <1 CFU/100 ml to meet drinking water standards. Solar units with reflectors disinfected the water sooner by increasing the water temperature by 8-10 degrees C to 64-75 degrees C. However, FRNA coliphages were still detected in these samples, indicating that this treatment may not inactivate pathogenic human enteric viruses. During cloudy conditions, reflectors only increased the water temperature by 3-4 degrees C to a maximum of 43-49 degrees C and E. coli was not completely inactivated. Under sunny and cloudy conditions, the UV wavelengths of sunlight worked synergistically with increasing water temperatures and were able to disinfect microorganisms at temperatures (45-56 degrees C), which were not effective in inactivating microorganisms. Relative resistance to the solar disinfecting effects were C. perfringens > FRNA coliphages > enterococci > E. coli > faecal coliform.

  13. Genotoxic potential of by-products in drinking water in relation to water disinfection: survey of pre-ozonated and post-chlorinated drinking water by Ames-test.

    PubMed

    Sujbert, László; Rácz, Gergely; Szende, Béla; Schröder, Heinz C; G Müller, Werner E; Török, Géza

    2006-02-15

    Mutagenic potential of drinking water samples derived from ranneywells was studied. 100-100 l of untreated (rough) and ozone-treated as well as chlorinated-disinfected water were dropped on and adsorbed by macroreticular resin columns (Serdolit PAD-III and Amberlite XAD-2). The adsorbed material was desorbed by methanol and dichloromethane. After elimination of the solvents by vacuum distillation the adsorbed material was dissolved in dimethylsulfoxide. The mutagenic activity was tested in the Ames-Salmonella/rat liver microsome system. The tester strains were TA-98 and TA-100. The material adsorbed to Serdolit PAD-III from rough and also disinfected water did not induce mutagenicity in case of the TA-98 tester strain, irrespective of activation by liver microsomes. However, the material adsorbed to Amberlite XAD-2 exerted mutagenic effect on the TA-98 tester strain, with and without liver microsome activation, both in case of rough and disinfected water. The TA-100 tester strain showed mutation after, but not without activation, when treated with the material adsorbed by either Serdolit PAD-III or Amberlite XAD-2, in case of rough water. Material derived from disinfected water and adsorbed to Serdolit PAD-III, caused mutation of the TA tester strain also only after activation. The material derived from disinfected water and adsorbed to Amberlite XAD-2 proved to be mutagenic to the TA-100 tester strain both without and after activation. Mutagenic activity was exerted by the amount of concentrates derived from 0.28 to 0.83 l of rough and 0.83-2.5l of disinfected water. The mutagenic activity of drinking water raises the possibility of carcinogenic effect, too. Search for alternative methods of water disinfection may be recommended.

  14. A New Group of Disinfection Byproducts in Drinking Water: Trihalo-hydroxy-cyclopentene-diones.

    PubMed

    Pan, Yang; Li, Wenbin; Li, Aimin; Zhou, Qing; Shi, Peng; Wang, Ying

    2016-07-19

    We report the detection, synthesis, preparative isolation, structure characterization and identification, and formation of a new group of drinking water disinfection byproducts (DBPs): trihalo-hydroxy-cyclopentene-diones (trihalo-HCDs). With ultra performance liquid chromatography (UPLC)/electrospray ionization-triple quadruple mass spectrometry analyses (full scans, multiple reaction monitoring, and product ion scans) and high-resolution mass spectrometry analyses (full scans), the new group of DBPs was identified with formulae and proposed with structures. However, due to a lack of commercially available standard compounds, structure identification of this new group of DBPs was challenging. 2,4,6-Trihydroxybenzaldehyde was found to be a good precursor for the synthesis of the tribromo species (m/z 345/347/349/351) in the new group of DBPs by reacting with bromine at a 2,4,6-trihydroxybenzaldehyde-to-bromine molar ratio of 1:8. With UPLC/photodiode array analysis (simultaneous 2- and 3-dimensional operations), the new DBP was determined to have a maximum UV absorption at the wavelength of 280 nm. Through isolation with high performance liquid chromatography/UV-triggered collections followed by lyophilization, the pure standard of the new DBP was obtained. Characterized with Fourier transform infrared spectroscopy, the pure standard of the new DBP was finally identified to be tribromo-HCD, and thus the new group of DBPs was identified to be trihalo-HCDs. On the basis of the disclosed structure, formation pathways of tribromo-HCD through reactions of three different precursors and bromine were proposed and partially verified. Moreover, increasing the bromide level in source water shifted the formation of trihalo-HCDs from being more chlorinated to being more brominated; with an increase in the contact time from 1 h to 5 d, the formation of trihalo-HCDs kept increasing in chloramination, whereas they kept decreasing in chlorination; with an increase in the pH from 6

  15. A New Group of Disinfection Byproducts in Drinking Water: Trihalo-hydroxy-cyclopentene-diones.

    PubMed

    Pan, Yang; Li, Wenbin; Li, Aimin; Zhou, Qing; Shi, Peng; Wang, Ying

    2016-07-19

    We report the detection, synthesis, preparative isolation, structure characterization and identification, and formation of a new group of drinking water disinfection byproducts (DBPs): trihalo-hydroxy-cyclopentene-diones (trihalo-HCDs). With ultra performance liquid chromatography (UPLC)/electrospray ionization-triple quadruple mass spectrometry analyses (full scans, multiple reaction monitoring, and product ion scans) and high-resolution mass spectrometry analyses (full scans), the new group of DBPs was identified with formulae and proposed with structures. However, due to a lack of commercially available standard compounds, structure identification of this new group of DBPs was challenging. 2,4,6-Trihydroxybenzaldehyde was found to be a good precursor for the synthesis of the tribromo species (m/z 345/347/349/351) in the new group of DBPs by reacting with bromine at a 2,4,6-trihydroxybenzaldehyde-to-bromine molar ratio of 1:8. With UPLC/photodiode array analysis (simultaneous 2- and 3-dimensional operations), the new DBP was determined to have a maximum UV absorption at the wavelength of 280 nm. Through isolation with high performance liquid chromatography/UV-triggered collections followed by lyophilization, the pure standard of the new DBP was obtained. Characterized with Fourier transform infrared spectroscopy, the pure standard of the new DBP was finally identified to be tribromo-HCD, and thus the new group of DBPs was identified to be trihalo-HCDs. On the basis of the disclosed structure, formation pathways of tribromo-HCD through reactions of three different precursors and bromine were proposed and partially verified. Moreover, increasing the bromide level in source water shifted the formation of trihalo-HCDs from being more chlorinated to being more brominated; with an increase in the contact time from 1 h to 5 d, the formation of trihalo-HCDs kept increasing in chloramination, whereas they kept decreasing in chlorination; with an increase in the pH from 6

  16. Assessing exposure in epidemiologic studies to disinfection by-products in drinking water: report from an international workshop.

    PubMed Central

    Arbuckle, Tye E; Hrudey, Steve E; Krasner, Stuart W; Nuckols, Jay R; Richardson, Susan D; Singer, Philip; Mendola, Pauline; Dodds, Linda; Weisel, Clifford; Ashley, David L; Froese, Kenneth L; Pegram, Rex A; Schultz, Irvin R; Reif, John; Bachand, Annette M; Benoit, Frank M; Lynberg, Michele; Poole, Charles; Waller, Kirsten

    2002-01-01

    The inability to accurately assess exposure has been one of the major shortcomings of epidemiologic studies of disinfection by-products (DBPs) in drinking water. A number of contributing factors include a) limited information on the identity, occurrence, toxicity, and pharmacokinetics of the many DBPs that can be formed from chlorine, chloramine, ozone, and chlorine dioxide disinfection; b) the complex chemical interrelationships between DBPs and other parameters within a municipal water distribution system; and c) difficulties obtaining accurate and reliable information on personal activity and water consumption patterns. In May 2000, an international workshop was held to bring together various disciplines to develop better approaches for measuring DBP exposure for epidemiologic studies. The workshop reached consensus about the clear need to involve relevant disciplines (e.g., chemists, engineers, toxicologists, biostatisticians and epidemiologists) as partners in developing epidemiologic studies of DBPs in drinking water. The workshop concluded that greater collaboration of epidemiologists with water utilities and regulators should be encouraged in order to make regulatory monitoring data more useful for epidemiologic studies. Similarly, exposure classification categories in epidemiologic studies should be chosen to make results useful for regulatory or policy decision making. PMID:11834463

  17. Characterization of biofilm and corrosion of cast iron pipes in drinking water distribution system with UV/Cl2 disinfection.

    PubMed

    Zhu, Ying; Wang, Haibo; Li, Xiaoxiao; Hu, Chun; Yang, Min; Qu, Jiuhui

    2014-09-01

    The effect of UV/Cl2 disinfection on the biofilm and corrosion of cast iron pipes in drinking water distribution system were studied using annular reactors (ARs). Passivation occurred more rapidly in the AR with UV/Cl2 than in the one with Cl2 alone, decreasing iron release for higher corrosivity of water. Based on functional gene, pyrosequencing assays and principal component analysis, UV disinfection not only reduced the required initial chlorine dose, but also enhanced denitrifying functional bacteria advantage in the biofilm of corrosion scales. The nitrate-reducing bacteria (NRB) Dechloromonas exhibited the greatest corrosion inhibition by inducing the redox cycling of iron to enhance the precipitation of iron oxides and formation of Fe3O4 in the AR with UV/Cl2, while the rhizobia Bradyrhizobium and Rhizobium, and the NRB Sphingomonas, Brucella producing siderophores had weaker corrosion-inhibition effect by capturing iron in the AR with Cl2. These results indicated that the microbial redox cycling of iron was possibly responsible for higher corrosion inhibition and lower effect of water Larson-Skold Index (LI) changes on corrosion. This finding could be applied toward the control of water quality in drinking water distribution systems.

  18. Occurrence of carboxylic acids in different steps of two drinking-water treatment plants using different disinfectants.

    PubMed

    Jurado-Sánchez, Beatriz; Ballesteros, Evaristo; Gallego, Mercedes

    2014-03-15

    The occurrence of 35 aliphatic and aromatic carboxylic acids within two full scale drinking-water treatment plants was evaluated for the first time in this research. At the intake of each plant (raw water), the occurrence of carboxylic acids varied according to the quality of the water source although in both cases 13 acids were detected at average concentrations of 6.9 and 4.7 μg/L (in winter). In the following steps in each treatment plant, the concentration patterns of these compounds differed depending on the type of disinfectant applied. Thus, after disinfection by chloramination, the levels of the acids remained almost constant (average concentration, 6.3 μg/L) and four new acids were formed (butyric, 2-methylbutyric, 3-hydroxybenzoic and 2-nitrobenzoic) at low levels (1.1-5 μg/L). When ozonation/chlorination was used, the total concentration of the carboxylic acids in the raw water sample (4.7 μg/L) increased up to 6 times (average concentration, 26.3 μg/L) after disinfection and 6 new acids (mainly aromatic) were produced at high levels (3.5-100 μg/L). Seasonal variations of the carboxylic acids under study showed that in both plants, maximum levels of all the analytes were reached in the coldest months (autumn and winter), aromatic acids only being found in those seasons.

  19. Occurrence of regulated and non-regulated disinfection by-products in small drinking water systems.

    PubMed

    Guilherme, Stéphanie; Rodriguez, Manuel J

    2014-12-01

    The occurrence of regulated and non-regulated disinfection by-products (DBPs) was investigated in the drinking water of small systems in two provinces in Canada, Newfoundland and Labrador (NL) and Quebec (QC), through an intensive sampling program. Sixteen DBPs were studied: four trihalomethanes (THMs), five haloacetic acids (HAAs), four haloacetonitriles (HANs), one halonitromethane, chloropikrin (CPK) and two haloketones (HKs). Average measured concentrations of these compounds were much higher than those reported in the literature for medium and large systems. The measured average value for THMs was 75 μg L(-1) (Stdv=69μgL(-1)); HAAs, 77 μg L(-1) (Stdv=75 μg L(-1)); HANs, 2.5 μg L(-1) (Stdv=1.8 μg L(-1)); CPK, 0.4 μg L(-1) (Stdv=0.3 μg L(-1)) and HKs, 6.0 μg L(-1) (Stdv=4.5 μg L(-1)). The gap (some 10 times difference) between the average levels of regulated DBPs (THMs, HAAs) and non-regulated DBPs (HANs, CPK and HKs) is comparable to that observed in large systems where the occurrence of the same compounds has been reported. Generally, investigated DBPs followed a comparable seasonal evolution during the year: they decreased between the fall and winter and then increased to eventually reach a maximum in late summer. This trend was less observable in NL than in QC. However, observed seasonal fluctuations of DBPs were less considerable than those observed in medium and large systems located in similar temperate environments reported in the literature. Spatial variations from the plant to the extremities were high and comparable to those observed in large systems, which is surprising, considering the smaller size of distribution networks supplying small communities. Generally speaking, the results support the premise that problems associated with implementing treatment that removes DBP precursors in water submitted to chlorination can increase population exposure to these contaminants in small systems.

  20. MASS SPECTROMETRY FOR RISK MANAGEMENT OF DRINKING WATER TREATMENT; II. DISINFECTION BY-PRODUCTS: HALOACETIC ACIDS

    EPA Science Inventory

    Risk management of drinking water relies on quality analytical data. Analytical methodology can often be adapted from environmental monitoring sources. However, risk management sometimes presents special analytical challenges because data may be needed from a source for which n...

  1. Silver-based Antibacterial Surfaces for Drinking Water Disinfection - An overview

    EPA Science Inventory

    Risks associated with current disinfection techniques, including the formation of disinfection by-products and multi-drug resistant bacterial species, have prompted the exploration of advanced disinfection methods. One such technique employs silver nanoparticles incorporation on ...

  2. Contribution of the Antibiotic Chloramphenicol and Its Analogues as Precursors of Dichloroacetamide and Other Disinfection Byproducts in Drinking Water.

    PubMed

    Chu, Wenhai; Krasner, Stuart W; Gao, Naiyun; Templeton, Michael R; Yin, Daqiang

    2016-01-01

    Dichloroacetamide (DCAcAm), a disinfection byproduct, has been detected in drinking water. Previous research showed that amino acids may be DCAcAm precursors. However, other precursors may be present. This study explored the contribution of the antibiotic chloramphenicol (CAP) and two of its analogues (thiamphenicol, TAP; florfenicol, FF) (referred to collectively as CAPs), which occur in wastewater-impacted source waters, to the formation of DCAcAm. Their formation yields were compared to free and combined amino acids, and they were investigated in filtered waters from drinking-water-treatment plants, heavily wastewater-impacted natural waters, and secondary effluents from wastewater treatment plants. CAPs had greater DCAcAm formation potential than two representative amino acid precursors. However, in drinking waters with ng/L levels of CAPs, they will not contribute as much to DCAcAm formation as the μg/L levels of amino acids. Also, the effect of advanced oxidation processes (AOPs) on DCAcAm formation from CAPs in real water samples during subsequent chlorination was evaluated. Preoxidation of CAPs with AOPs reduced the formation of DCAcAm during postchlorination. The results of this study suggest that CAPs should be considered as possible precursors of DCAcAm, especially in heavily wastewater-impacted waters.

  3. Characterization and determination of chloro- and bromo-benzoquinones as new chlorination disinfection byproducts in drinking water.

    PubMed

    Zhao, Yuli; Qin, Feng; Boyd, Jessica M; Anichina, Janna; Li, Xing-Fang

    2010-06-01

    We report the characterization and determination of 2,6-dichloro-1,4-benzoquinone and three new disinfection byproducts (DBPs): 2,6-dichloro-3-methyl-1,4-benzoquinone, 2,3,6-trichloro-1,4-benzoquinone, and 2,6-dibromo-1,4-benzoquinone. These haloquinones are suspected bladder carcinogens and are likely produced during drinking water disinfection treatment. However, detection of these haloquinones is challenging, and consequently, they have not been characterized as DBPs until recently. We have developed an electrospray ionization tandem mass spectrometry technique based on our observation of unique ionization processes. These chloro- and bromo-quinones were ionized through a reduction step to form [M + H](-) under negative electrospray ionization. Tandem mass spectra and accurate mass measurements of these compounds showed major product ions, [M + H - HX](-), [M + H - HX - CO](-), [M + H - CO](-), and/or X(-) (where X represents Cl or Br). The addition of 0.25% formic acid to water samples was found to effectively stabilize the haloquinones in water and to improve the ionization for analysis. These improvements were rationalized from the estimates of pK(a) values (5.8-6.3) of these haloquinones. The method of tandem mass spectrometry detection, combined with sample preservation, solid phase extraction, and liquid chromatography separation, enabled the detection of haloquinones in chlorinated water samples collected from a drinking water treatment plant. The four haloquinones were detected only in drinking water after chlorination treatment, with concentrations ranging from 0.5 to 165 ng/L, but were not detectable in the untreated water. This method will be useful for future studies of occurrence, formation pathways, toxicity, and control of these new halogenated DBPs.

  4. Sample Enrichment for Bioanalytical Assessment of Disinfected Drinking Water: Concentrating the Polar, the Volatiles, and the Unknowns.

    PubMed

    Stalter, Daniel; Peters, Leon I; O'Malley, Elissa; Tang, Janet Yat-Man; Revalor, Marion; Farré, Maria José; Watson, Kalinda; von Gunten, Urs; Escher, Beate I

    2016-06-21

    Enrichment methods used in sample preparation for the bioanalytical assessment of disinfected drinking water result in the loss of volatile and hydrophilic disinfection byproducts (DBPs) and hence likely tend to underestimate biological effects. We developed and evaluated methods that are compatible with bioassays, for extracting nonvolatile and volatile DBPs from chlorinated and chloraminated drinking water to minimize the loss of analytes. For nonvolatile DBPs, solid-phase extraction (SPE) with TELOS ENV as solid phase performed superior compared to ten other sorbents. SPE yielded >70% recovery of nonpurgeable adsorbable organic halogens (AOX). For volatile DBPs, cryogenic vacuum distillation performed unsatisfactorily. Purge and cold-trap with crushed ice serving as condensation nuclei achieved recoveries of 50-100% for trihalomethanes and haloacetonitriles and approximately 60-90% for purged AOX from tap water. We compared the purgeable versus the nonpurgeable fraction by combining purge-and-trap extraction with SPE. The purgeable DBP fraction enriched with the purge-and-trap method exerted a lower oxidative stress response in mammalian cells than the nonpurgeable DBPs enriched with SPE after purging, while contributions of both fractions to bacterial cytotoxicity was more variable. 37 quantified DBPs explained almost the entire AOX in the purge-and-trap extracts, but <16% in the SPE extracts demonstrating that the nonpurgeable fraction is dominated by unknown DBPs. PMID:27153244

  5. Sample Enrichment for Bioanalytical Assessment of Disinfected Drinking Water: Concentrating the Polar, the Volatiles, and the Unknowns.

    PubMed

    Stalter, Daniel; Peters, Leon I; O'Malley, Elissa; Tang, Janet Yat-Man; Revalor, Marion; Farré, Maria José; Watson, Kalinda; von Gunten, Urs; Escher, Beate I

    2016-06-21

    Enrichment methods used in sample preparation for the bioanalytical assessment of disinfected drinking water result in the loss of volatile and hydrophilic disinfection byproducts (DBPs) and hence likely tend to underestimate biological effects. We developed and evaluated methods that are compatible with bioassays, for extracting nonvolatile and volatile DBPs from chlorinated and chloraminated drinking water to minimize the loss of analytes. For nonvolatile DBPs, solid-phase extraction (SPE) with TELOS ENV as solid phase performed superior compared to ten other sorbents. SPE yielded >70% recovery of nonpurgeable adsorbable organic halogens (AOX). For volatile DBPs, cryogenic vacuum distillation performed unsatisfactorily. Purge and cold-trap with crushed ice serving as condensation nuclei achieved recoveries of 50-100% for trihalomethanes and haloacetonitriles and approximately 60-90% for purged AOX from tap water. We compared the purgeable versus the nonpurgeable fraction by combining purge-and-trap extraction with SPE. The purgeable DBP fraction enriched with the purge-and-trap method exerted a lower oxidative stress response in mammalian cells than the nonpurgeable DBPs enriched with SPE after purging, while contributions of both fractions to bacterial cytotoxicity was more variable. 37 quantified DBPs explained almost the entire AOX in the purge-and-trap extracts, but <16% in the SPE extracts demonstrating that the nonpurgeable fraction is dominated by unknown DBPs.

  6. Balancing the risks and benefits of drinking water disinfection: disability adjusted life-years on the scale.

    PubMed

    Havelaar, A H; De Hollander, A E; Teunis, P F; Evers, E G; Van Kranen, H J; Versteegh, J F; Van Koten, J E; Slob, W

    2000-04-01

    To evaluate the applicability of disability adjusted life-years (DALYs) as a measure to compare positive and negative health effects of drinking water disinfection, we conducted a case study involving a hypothetical drinking water supply from surface water. This drinking water supply is typical in The Netherlands. We compared the reduction of the risk of infection with Cryptosporidium parvum by ozonation of water to the concomitant increase in risk of renal cell cancer arising from the production of bromate. We applied clinical, epidemiologic, and toxicologic data on morbidity and mortality to calculate the net health benefit in DALYs. We estimated the median risk of infection with C. parvum as 10(-3)/person-year. Ozonation reduces the median risk in the baseline approximately 7-fold, but bromate is produced in a concentration above current guideline levels. However, the health benefits of preventing gastroenteritis in the general population and premature death in patients with acquired immunodeficiency syndrome outweigh health losses by premature death from renal cell cancer by a factor of > 10. The net benefit is approximately 1 DALY/million person-years. The application of DALYs in principle allows us to more explicitly compare the public health risks and benefits of different management options. In practice, the application of DALYs may be hampered by the substantial degree of uncertainty, as is typical for risk assessment.

  7. Solar Radiation Disinfection of Drinking Water at Temperate Latitudes: Inactivation rates for an optimized reactor configuration

    EPA Science Inventory

    Solar radiation-driven inactivation of bacteria, virus and protozoan pathogen models was quantified in simulated drinking water at a temperate latitude (34°S). The water was seeded with Enterococcus faecalis, Clostridium sporogenes spores, and P22 bacteriophage, each at ca 1 x 10...

  8. Solar Disinfection Improves Drinking Water Quality to Prevent Diarrhea in Under-Five Children in Sikkim, India

    PubMed Central

    Rai, BB; Pal, Ranabir; Kar, Sumit; Tsering, Dechen C

    2010-01-01

    Background: Solar radiations improve the microbiological quality of water and offer a method for disinfection of drinking water that requires few resources and no expertise and may reduce the prevalence of diarrhea among under-five children. Aims and Objectives: To find out the reduction in the prevalence of diarrhea in the under-five children after consumption of potable water treated with solar disinfection method. Materials and Methods: This was a population-based interventional prospective study in the urban slum area of Mazegoan, Jorethang, south Sikkim, during the period 1st May 2007 to 30th November 2007 on 136 children in the under-five age group in 102 households selected by random sampling. Main outcome measure was the assessment of the reduction of the prevalence of diarrhea among under-five children after consumption of potable water treated with solar disinfection method practiced by the caregivers in the intervention group keeping water in polyethylene terephthalate (PET) bottles as directed by the investigators. The data were collected by the interview method using a pre-tested questionnaire prepared on the basis of socio-demographics and prevalence of diarrhea. The data were subjected to percentages and chi-square tests, which were used to find the significance. Results: After four weeks of intervention among the study group, the diarrhea prevalence was 7.69% among solar disinfection (SODIS) users, while 31.82% prevalence was observed among non-users in that period; the reduction in prevalence of diarrhea was 75.83%. After eight weeks of intervention, the prevalence of diarrhea was 7.58% among SODIS users and 31.43% among non-users; the reduction in diarrhea was 75.88% in the study group. The findings were found to be statistically significant. Conclusions: In our study, we observed that the prevalence of diarrhea decreased significantly after solar disinfection of water was practiced by the caregivers keeping potable water in PET bottles in the

  9. Safe drinking water act

    SciTech Connect

    Calabrese, E.J.; Gilbert, C.E. )

    1989-01-01

    This book covers drinking water regulations such as disinfectant by-products, synthetic organics, inorganic chemicals, microbiological contaminants, volatile organic chemicals, radionuclides, fluoride, toxicological approaches to setting new national drinking water regulations, and trihalomethanes. Gives organic and inorganic compounds scheduled to be regulated in 1989 and candidates for the 1990s regulations.

  10. Effect of Batch-Process Solar Disinfection on Survival of Cryptosporidium parvum Oocysts in Drinking Water

    PubMed Central

    Méndez-Hermida, F.; Castro-Hermida, J. A.; Ares-Mazás, E.; Kehoe, S. C.; McGuigan, K. G.

    2005-01-01

    The results of batch-process solar disinfection (SODIS) of Cryptosporidium parvum oocysts in water are reported. Oocyst suspensions were exposed to simulated sunlight (830 W m−2) at 40°C. Viability assays (4′,6′-diamidino-2-phenylindole [DAPI]/propidium iodide and excystation) and infectivity tests (Swiss CD-1 suckling mice) were performed. SODIS exposures of 6 and 12 h reduced oocyst infectivity from 100% to 7.5% (standard deviation = 2.3) and 0% (standard deviation = 0.0), respectively. PMID:15746372

  11. Effect of batch-process solar disinfection on survival of Cryptosporidium parvum oocysts in drinking water.

    PubMed

    Méndez-Hermida, F; Castro-Hermida, J A; Ares-Mazás, E; Kehoe, S C; McGuigan, K G

    2005-03-01

    The results of batch-process solar disinfection (SODIS) of Cryptosporidium parvum oocysts in water are reported. Oocyst suspensions were exposed to simulated sunlight (830 W m(-2)) at 40 degrees C. Viability assays (4',6'-diamidino-2-phenylindole [DAPI]/propidium iodide and excystation) and infectivity tests (Swiss CD-1 suckling mice) were performed. SODIS exposures of 6 and 12 h reduced oocyst infectivity from 100% to 7.5% (standard deviation = 2.3) and 0% (standard deviation = 0.0), respectively.

  12. Disinfection byproduct formation in reverse-osmosis concentrated and lyophilized natural organic matter from a drinking water source.

    PubMed

    Pressman, Jonathan G; McCurry, Daniel L; Parvez, Shahid; Rice, Glenn E; Teuschler, Linda K; Miltner, Richard J; Speth, Thomas F

    2012-10-15

    Drinking water treatment and disinfection byproduct (DBP) research can be complicated by natural organic matter (NOM) temporal variability. NOM preservation by lyophilization (freeze-drying) has been long practiced to address this issue; however, its applicability for drinking water research has been limited because the selected NOM sources are atypical of most drinking water sources. The purpose of this research was to demonstrate that reconstituted NOM from a lyophilized reverse-osmosis (RO) concentrate of a typical drinking water source closely represents DBP formation in the original NOM. A preliminary experiment assessed DBP formation kinetics and yields in concentrated NOM, which demonstrated that chlorine decays faster in concentrate, in some cases leading to altered DBP speciation. Potential changes in NOM reactivity caused by lyophilization were evaluated by chlorination of lyophilized and reconstituted NOM, its parent RO concentrate, and the source water. Bromide lost during RO concentration was replaced by adding potassium bromide prior to chlorination. Although total measured DBP formation tended to decrease slightly and unidentified halogenated organic formation tended to increase slightly as a result of RO concentration, the changes associated with lyophilization were minor. In lyophilized NOM reconstituted back to source water TOC levels and then chlorinated, the concentrations of 19 of 21 measured DBPs, constituting 96% of the total identified DBP mass, were statistically indistinguishable from those in the chlorinated source water. Furthermore, the concentrations of 16 of 21 DBPs in lyophilized NOM reconstituted back to the RO concentrate TOC levels, constituting 86% DBP mass, were statistically indistinguishable from those in the RO concentrate. This study suggests that lyophilization can be used to preserve concentrated NOM without substantially altering the precursors to DBP formation.

  13. Mutagenic activity associated with by-products of drinking water disinfection by chlorine, chlorine dioxide, ozone and UV-irradiation.

    PubMed

    Zoeteman, B C; Hrubec, J; de Greef, E; Kool, H J

    1982-12-01

    A retrospective epidemiological study in The Netherlands showed a statistical association between chlorination by-products in drinking water and cancer of the esophagus and stomach for males. A pilot-plant study with alternative disinfectants was carried out with stored water of the Rivers Rhine and Meuse. It was demonstrated that the increase of direct acting mutagens after treatment with chlorine dioxide is similar to the effect of chlorination. Ozonation of Rhine water reduced the mutagenic activity for Salmonella typhimurium TA 98 both with and without metabolic activation. UV alone hardly affects the mutagenicity of the stored river water for S. typh. TA 98. In all studies, practically no mutagenic activity for S. typh. TA 100 was found. Although remarkable changes in the concentration of individual organic compounds are reported, the identity of the mutagens detected is yet unclear. Compounds of possible interest due to their removal by ozonation are 1,3,3-trimethyloxindole, dicyclopentadiene and several alkylquinolines. Compounds which might be responsible for the increased mutagenicity after chlorination are two brominated acetonitriles and tri(2-chlorethyl) phosphate. Furthermore, the concentration procedure with adsorption on XAD resin and the subsequent elution step may have affected the results. It is proposed to focus further research more on the less volatile by-products of disinfection than on the trihalomethanes.

  14. MULTISPECTRAL IDENTIFICATION OF CHLORINE DIOXIDE DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    This paper discusses the identification of organic disinfection by-products (DBPs) at a pilot plant in Evansville, Indiana, that uses chlorine dioxide as a primary disinfectant. nconventional multispectral identification techniques (gas chromatography combined with high and low r...

  15. Frequency of use controls chemical leaching from drinking-water containers subject to disinfection.

    PubMed

    Andra, Syam S; Makris, Konstantinos C; Shine, James P

    2011-12-15

    Microbial-, and chemical-based burden of disease associated with lack of access to safe water continues to primarily impact developing countries. Cost-effective health risk-mitigating measures, such as of solar disinfection applied to microbial-contaminated water stored in plastic bottles have been increasingly tested in developing countries adversely impacted by epidemic water-borne diseases. Public health concerns associated with chemical leaching from water packaging materials led us to investigate the magnitude and variability of antimony (Sb) and bromine (Br) leaching from reused plastic containers (polyethylene terephthalate, PET; and polycarbonate, PC) subject to UV and/or temperature-driven disinfection. The overall objective of this study was to determine the main and interactive effects of temperature, UV exposure duration, and frequency of bottle reuse on the extent of leaching of Sb and Br from plastic bottles into water. Regardless of UV exposure duration, frequency of reuse (up to 27 times) was the major factor that linearly increased Sb leaching from PET bottles at all temperatures tested (13-47 °C). Leached Sb concentrations (∼360 ng L(-1)) from the highly reused (27 times) PET bottles (minimal Sb leaching from PC bottles, <15 ng L(-1)) did not pose a serious risk to human health according to current daily Sb acceptable intake estimates. Leached Br concentrations from both PET and PC containers (up to ∼15 μg L(-1)) did not pose a consumer health risk either, however, no acceptable daily dose estimates exist for oral ingestion of organo-brominated, or other plasticizers/additives compounds if they were to be found in bottled water at much lower concentrations. Additional research on potential leaching of organic chemicals from water packaging materials is deemed necessary under relevant environmental conditions.

  16. Frequency of use controls chemical leaching from drinking-water containers subject to disinfection.

    PubMed

    Andra, Syam S; Makris, Konstantinos C; Shine, James P

    2011-12-15

    Microbial-, and chemical-based burden of disease associated with lack of access to safe water continues to primarily impact developing countries. Cost-effective health risk-mitigating measures, such as of solar disinfection applied to microbial-contaminated water stored in plastic bottles have been increasingly tested in developing countries adversely impacted by epidemic water-borne diseases. Public health concerns associated with chemical leaching from water packaging materials led us to investigate the magnitude and variability of antimony (Sb) and bromine (Br) leaching from reused plastic containers (polyethylene terephthalate, PET; and polycarbonate, PC) subject to UV and/or temperature-driven disinfection. The overall objective of this study was to determine the main and interactive effects of temperature, UV exposure duration, and frequency of bottle reuse on the extent of leaching of Sb and Br from plastic bottles into water. Regardless of UV exposure duration, frequency of reuse (up to 27 times) was the major factor that linearly increased Sb leaching from PET bottles at all temperatures tested (13-47 °C). Leached Sb concentrations (∼360 ng L(-1)) from the highly reused (27 times) PET bottles (minimal Sb leaching from PC bottles, <15 ng L(-1)) did not pose a serious risk to human health according to current daily Sb acceptable intake estimates. Leached Br concentrations from both PET and PC containers (up to ∼15 μg L(-1)) did not pose a consumer health risk either, however, no acceptable daily dose estimates exist for oral ingestion of organo-brominated, or other plasticizers/additives compounds if they were to be found in bottled water at much lower concentrations. Additional research on potential leaching of organic chemicals from water packaging materials is deemed necessary under relevant environmental conditions. PMID:22040714

  17. Development and evaluation of a reflective solar disinfection pouch for treatment of drinking water.

    PubMed

    Walker, D Carey; Len, Soo-Voon; Sheehan, Brita

    2004-04-01

    A second-generation solar disinfection (SODIS) system (pouch) was constructed from food-grade, commercially available packaging materials selected to fully transmit and amplify the antimicrobial properties of sunlight. Depending upon the season, water source, and challenge organism, culturable bacteria were reduced between 3.5 and 5.5 log cycles. The system was also capable of reducing the background presumptive coliform population in nonsterile river water below the level of detection. Similar experiments conducted with a model virus, the F-specific RNA bacteriophage MS2, indicated that the pouch was slightly less efficient, reducing viable plaques by 3.5 log units in comparison to a 5.0 log reduction of enterotoxigenic Escherichia coli O18:H11 within the same time period. These results suggest that water of poor microbiological quality can be improved by using a freely available resource (sunlight) and a specifically designed plastic pouch constructed of food-grade packaging materials.

  18. Development and Evaluation of a Reflective Solar Disinfection Pouch for Treatment of Drinking Water

    PubMed Central

    Walker, D. Carey; Len, Soo-Voon; Sheehan, Brita

    2004-01-01

    A second-generation solar disinfection (SODIS) system (pouch) was constructed from food-grade, commercially available packaging materials selected to fully transmit and amplify the antimicrobial properties of sunlight. Depending upon the season, water source, and challenge organism, culturable bacteria were reduced between 3.5 and 5.5 log cycles. The system was also capable of reducing the background presumptive coliform population in nonsterile river water below the level of detection. Similar experiments conducted with a model virus, the F-specific RNA bacteriophage MS2, indicated that the pouch was slightly less efficient, reducing viable plaques by 3.5 log units in comparison to a 5.0 log reduction of enterotoxigenic Escherichia coli O18:H11 within the same time period. These results suggest that water of poor microbiological quality can be improved by using a freely available resource (sunlight) and a specifically designed plastic pouch constructed of food-grade packaging materials. PMID:15066858

  19. Inactivation and injury of total coliform bacteria after primary disinfection of drinking water by TiO2 photocatalysis.

    PubMed

    Rizzo, Luigi

    2009-06-15

    In this study the potential application of TiO(2) photocatalysis as primary disinfection system of drinking water was investigated in terms of coliform bacteria inactivation and injury. As model water the effluent of biological denitrification unit for nitrate removal from groundwater, which is characterized by high organic matter and bacteria release, was used. The injury of photocatalysis on coliform bacteria was characterized by means of selective (mEndo) and less selective (mT7) culture media. Different catalyst loadings as well as photolysis and adsorption effects were investigated. Photocatalysis was effective in coliform bacteria inactivation (91-99% after 60 min irradiation time, depending on both catalyst loading and initial density of coliform bacteria detected by mEndo), although no total removal was observed after 60 min irradiation time. The contribution of adsorption mechanism was significant (60-98% after 60 min, depending on catalyst loading) compared to previous investigations probably due to the nature of source water rich in particulate organic matter and biofilm. Photocatalysis process did not result in any irreversible injury (98.8% being the higher injury) under investigated conditions, thus a bacteria regrowth may take place under optimum environment conditions if any final disinfection process (e.g., chlorine or chlorine dioxide) is not used.

  20. DISRUPTION IN RAT ESTROUS CYCLICITY BY THE DRINKING WATER DISINFECTANT BY-PRODUCT DIBROMOACETIC ACID: RELATIONSHIP TO A SUPPRESSION ON ESTRADIOL METABOLISM?

    EPA Science Inventory

    Disruption in Rat Estrous Cyclicity by the Drinking Water Disinfectant By-Product Dibromoacetic Acid: Relationship to A Suppression on Estradiol Metabolism?

    Ashley S. Murr and Jerome M. Goldman, Endocrinology Branch, Reproductive Toxicology Division National Health and En...

  1. ALTERATION OF ESTROUS CYCLICITY BY THE DRINKING WATER DISINFECTION BY-PRODUCT DIBROMOACETIC ACID: RELATIONSHIP TO AN EFFECT ON ESTRADIOL METABOLISM?

    EPA Science Inventory

    A number of chemicals formed by disinfection of municipal drinking water have been suspected to cause reproductive alterations in humans and test animals. One class of these chemicals, the haloacetic acids, have been reported to alter a number of rat testicular endpoints, includ...

  2. CHLORINATED VS. CHLORAMINATED DRINKING WATER: TOXICITY-BASED IDENTIFICATION OF DISINFECTION BY-PRODUCTS USING ESI-MS AND ESI-MS/MS

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are of concern because some epidemiologic studies have shown that some DBPs are associated with cancer or adverse reproductive/developmental effects in human populations, and other studies have shown that certain DBPs cause similar h...

  3. EVALUATION OF THE IMMUNOMODULATORY EFFECTS OF THE DISINFECTION BYPRODUCT, SODIUM CHLORITE, IN FEMALE B6C3F1 MICE: A DRINKING WATER STUDY

    EPA Science Inventory

    Evaluation of the Immunomodulatory Effects of the Disinfection By-product, Sodium chlorite, in Female B6C3f1 mice: A Drinking Water Study.

    Niel A. Karrow, Tal, L. Guo, J. Ann McCay, Greg W. Johnson, Ronnetta D. Brown, Debrorah L. Musgrove, Dori R. Germolec, Robert W. Lueb...

  4. MEETING IN CHINA: CHLORINATED VS. CHLORAMINATED DRINKING WATER: TOXICITY-BASED IDENTIFICATION OF DISINFECTION BY-PRODUCTS USING ESI-MS AND ESI-MS/MS

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are of concern because epidemiologic studies have shown that they are associated with bladder cancer and adverse reproductive/developmental effects in human populations, and some cause cancer in laboratory animals. As a result, the U...

  5. Meeting in Canada: Chlorinated vs. Chloraminated Drinking Water: Toxicity-Based Identification of Disinfection By-Products Using ESI-MS and ESI-MS/MS

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are of concern because epidemiologic studies have shown that they are associated with bladder cancer and adverse reproductive/developmental effects in human populations. There is almost no information on high molecular weight DBPs (>...

  6. CARCINOGENICITY OF INDIVIDUAL AND A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS IN A RAT MODEL OF HEREDITARY RENAL CELL CARCINOMA

    EPA Science Inventory

    Carcinogenicity of Individual and a Mixture of Drinking Water Disinfection By-Products in a Rat Model of Hereditary Renal Cell Carcinoma

    Eker rats develop hereditary renal cell carcinoma secondary to a germline mutation in the tuberous sclerosis 2 (Tsc2) gene and are ligh...

  7. COMPONENT-BASED AND WHOLE-MIXTURE TECHNIQUES FOR ADDRESSING THE TOXICITY OF DRINKING WATER DISINFECTION BYPRODUCT MIXTURES

    EPA Science Inventory

    ABSTRACT

    Chemical disinfection of water is of direct public health benefit as it results in decreased waterborne illness. The chemicals used to disinfect water react with naturally occurring organic matter and bromide in the source water, resulting in the formation of a m...

  8. Removal of soluble microbial products as the precursors of disinfection by-products in drinking water supplies.

    PubMed

    Liu, Jin-Lin; Li, Xiao-Yan

    2015-01-01

    Water pollution worsens the problem of disinfection by-products (DBPs) in drinking water supply. Biodegradation of wastewater organics produces soluble microbial products (SMPs), which can be important DBP precursors. In this laboratory study, a number of enhanced water treatment methods for DBP control, including enhanced coagulation, ozonation, and activated carbon adsorption, were evaluated for their effectiveness in treating SMP-containing water for the DBP reduction purpose. The results show that enhanced coagulation with alum could remove SMPs only marginally and decrease the DBP formation potential (DBPFP) of the water by less than 20%. Although ozone could cause destruction of SMPs in water, the overall DBPFP of the water did not decrease but increased after ozonation. In contrast, adsorption by granular activated carbon could remove the SMP organics from water by more than 60% and reduce the DBPFP by more than 70%. It is apparent that enhanced coagulation and ozonation are not suitable for the removal of SMPs as DBP precursors from polluted water, although enhanced coagulation has been commonly used to reduce the DBP formation caused by natural organic matter. In comparison, activated carbon adsorption is shown as a more effective means to remove the SMP content from water and hence to control the wastewater-derived DBP problem in water supply.

  9. Removal of soluble microbial products as the precursors of disinfection by-products in drinking water supplies.

    PubMed

    Liu, Jin-Lin; Li, Xiao-Yan

    2015-01-01

    Water pollution worsens the problem of disinfection by-products (DBPs) in drinking water supply. Biodegradation of wastewater organics produces soluble microbial products (SMPs), which can be important DBP precursors. In this laboratory study, a number of enhanced water treatment methods for DBP control, including enhanced coagulation, ozonation, and activated carbon adsorption, were evaluated for their effectiveness in treating SMP-containing water for the DBP reduction purpose. The results show that enhanced coagulation with alum could remove SMPs only marginally and decrease the DBP formation potential (DBPFP) of the water by less than 20%. Although ozone could cause destruction of SMPs in water, the overall DBPFP of the water did not decrease but increased after ozonation. In contrast, adsorption by granular activated carbon could remove the SMP organics from water by more than 60% and reduce the DBPFP by more than 70%. It is apparent that enhanced coagulation and ozonation are not suitable for the removal of SMPs as DBP precursors from polluted water, although enhanced coagulation has been commonly used to reduce the DBP formation caused by natural organic matter. In comparison, activated carbon adsorption is shown as a more effective means to remove the SMP content from water and hence to control the wastewater-derived DBP problem in water supply. PMID:25241751

  10. Identification of developmentally toxic drinking water disinfection byproducts and evaluation of data relevant to mode of action

    SciTech Connect

    Colman, Joan; Rice, Glenn E.; Wright, J. Michael; Hunter, E. Sidney; Teuschler, Linda K.; Lipscomb, John C.; Hertzberg, Richard C.; Simmons, Jane Ellen; Fransen, Margaret; Osier, Mark; Narotsky, Michael G.

    2011-07-15

    Reactions between chemicals used to disinfect drinking water and compounds present in source waters produce chemical mixtures containing hundreds of disinfection byproducts (DBPs). Although the results have been somewhat inconsistent, some epidemiological studies suggest associations may exist between DBP exposures and adverse developmental outcomes. The potencies of individual DBPs in rodent and rabbit developmental bioassays suggest that no individual DBP can account for the relative risk estimates reported in the positive epidemiologic studies, leading to the hypothesis that these outcomes could result from the toxicity of DBP mixtures. As a first step in a mixtures risk assessment for DBP developmental effects, this paper identifies developmentally toxic DBPs and examines data relevant to the mode of action (MOA) for DBP developmental toxicity. We identified 24 developmentally toxic DBPs and four adverse developmental outcomes associated with human DBP exposures: spontaneous abortion, cardiovascular defects, neural tube defects, and low birth weight infancy. A plausible MOA, involving hormonal disruption of pregnancy, is delineated for spontaneous abortion, which some epidemiologic studies associate with total trihalomethane and bromodichloromethane exposures. The DBP data for the other three outcomes were inadequate to define key MOA steps.

  11. Drinking-Water Disinfection By-products and Semen Quality: A Cross-Sectional Study in China

    PubMed Central

    Zeng, Qiang; Wang, Yi-Xin; Xie, Shao-Hua; Xu, Liang; Chen, Yong-Zhe; Li, Min; Yue, Jing; Li, Yu-Feng; Liu, Ai-Lin

    2014-01-01

    Background: Exposure to disinfection by-products (DBPs) has been demonstrated to impair male reproductive health in animals, but human evidence is limited and inconsistent. Objective: We examined the association between exposure to drinking-water DBPs and semen quality in a Chinese population. Methods: We recruited 2,009 men seeking semen analysis from the Reproductive Center of Tongji Hospital in Wuhan, China, between April 2011 and May 2012. Each man provided a semen sample and a urine sample. Semen samples were analyzed for sperm concentration, sperm motility, and sperm count. As a biomarker of exposure to drinking-water DBPs, trichloroacetic acid (TCAA) was measured in the urine samples. Results: The mean (median) urinary TCAA concentration was 9.58 (7.97) μg/L (interquartile range, 6.01–10.96 μg/L). Compared with men with urine TCAA in the lowest quartile, increased adjusted odds ratios (ORs) were estimated for below-reference sperm concentration in men with TCAA in the second and fourth quartiles (OR = 1.79; 95% CI: 1.19, 2.69 and OR = 1.51; 95% CI: 0.98, 2.31, respectively), for below-reference sperm motility in men with TCAA in the second and third quartiles (OR = 1.46; 95% CI: 1.12, 1.90 and OR = 1.30; 95% CI: 1.00, 1.70, respectively), and for below-reference sperm count in men with TCAA in the second quartile (OR 1.62; 95% CI: 1.04, 2.55). Nonmonotonic associations with TCAA quartiles were also estimated for semen parameters modeled as continuous outcomes, although significant negative associations were estimated for all quartiles above the reference level for sperm motility. Conclusion: Our findings suggest that exposure to drinking-water DBPs may contribute to decreased semen quality in humans. Citation: Zeng Q, Wang YX, Xie SH, Xu L, Chen YZ, Li M, Yue J, Li YF, Liu AL, Lu WQ. 2014. Drinking-water disinfection by-products and semen quality: a cross-sectional study in China. Environ Health Perspect 122:741–746; http://dx.doi.org/10.1289/ehp

  12. Evaluating Evidence for Association of Human Bladder Cancer with Drinking-Water Chlorination Disinfection By-Products.

    PubMed

    Hrudey, Steve E; Backer, Lorraine C; Humpage, Andrew R; Krasner, Stuart W; Michaud, Dominique S; Moore, Lee E; Singer, Philip C; Stanford, Benjamin D

    2015-01-01

    Exposure to chlorination disinfection by-products (CxDBPs) is prevalent in populations using chlorination-based methods to disinfect public water supplies. Multifaceted research has been directed for decades to identify, characterize, and understand the toxicology of these compounds, control and minimize their formation, and conduct epidemiologic studies related to exposure. Urinary bladder cancer has been the health risk most consistently associated with CxDBPs in epidemiologic studies. An international workshop was held to (1) discuss the qualitative strengths and limitations that inform the association between bladder cancer and CxDBPs in the context of possible causation, (2) identify knowledge gaps for this topic in relation to chlorine/chloramine-based disinfection practice(s) in the United States, and (3) assess the evidence for informing risk management. Epidemiological evidence linking exposures to CxDBPs in drinking water to human bladder cancer risk provides insight into causality. However, because of imprecise, inaccurate, or incomplete estimation of CxDBPs levels in epidemiologic studies, translation from hazard identification directly to risk management and regulatory policy for CxDBPs can be challenging. Quantitative risk estimates derived from toxicological risk assessment for CxDBPs currently cannot be reconciled with those from epidemiologic studies, notwithstanding the complexities involved, making regulatory interpretation difficult. Evidence presented here has both strengths and limitations that require additional studies to resolve and improve the understanding of exposure response relationships. Replication of epidemiologic findings in independent populations with further elaboration of exposure assessment is needed to strengthen the knowledge base needed to better inform effective regulatory approaches.

  13. Evaluating Evidence for Association of Human Bladder Cancer with Drinking-Water Chlorination Disinfection By-Products

    PubMed Central

    Hrudey, Steve E.; Backer, Lorraine C.; Humpage, Andrew R.; Krasner, Stuart W.; Michaud, Dominique S.; Moore, Lee E.; Singer, Philip C.; Stanford, Benjamin D.

    2015-01-01

    Exposure to chlorination disinfection by-products (CxDBPs) is prevalent in populations using chlorination-based methods to disinfect public water supplies. Multifaceted research has been directed for decades to identify, characterize, and understand the toxicology of these compounds, control and minimize their formation, and conduct epidemiologic studies related to exposure. Urinary bladder cancer has been the health risk most consistently associated with CxDBPs in epidemiologic studies. An international workshop was held to (1) discuss the qualitative strengths and limitations that inform the association between bladder cancer and CxDBPs in the context of possible causation, (2) identify knowledge gaps for this topic in relation to chlorine/chloramine-based disinfection practice(s) in the United States, and (3) assess the evidence for informing risk management. Epidemiological evidence linking exposures to CxDBPs in drinking water to human bladder cancer risk provides insight into causality. However, because of imprecise, inaccurate, or incomplete estimation of CxDBPs levels in epidemiologic studies, translation from hazard identification directly to risk management and regulatory policy for CxDBPs can be challenging. Quantitative risk estimates derived from toxicological risk assessment for CxDBPs currently cannot be reconciled with those from epidemiologic studies, notwithstanding the complexities involved, making regulatory interpretation difficult. Evidence presented here has both strengths and limitations that require additional studies to resolve and improve the understanding of exposure response relationships. Replication of epidemiologic findings in independent populations with further elaboration of exposure assessment is needed to strengthen the knowledge base needed to better inform effective regulatory approaches. PMID:26309063

  14. Drinking Water

    MedlinePlus

    ... the safest water supplies in the world, but drinking water quality can vary from place to place. It ... water supplier must give you annual reports on drinking water. The reports include where your water came from ...

  15. Human cell toxicogenomic analysis linking reactive oxygen species to the toxicity of monohaloacetic acid drinking water disinfection byproducts.

    PubMed

    Pals, Justin; Attene-Ramos, Matias S; Xia, Menghang; Wagner, Elizabeth D; Plewa, Michael J

    2013-01-01

    Chronic exposure to drinking water disinfection byproducts has been linked to adverse health risks. The monohaloacetic acids (monoHAAs) are generated as byproducts during the disinfection of drinking water and are cytotoxic, genotoxic, mutagenic, and teratogenic. Iodoacetic acid toxicity was mitigated by antioxidants, suggesting the involvement of oxidative stress. Other monoHAAs may share a similar mode of action. Each monoHAA generated a significant concentration-response increase in the expression of a β-lactamase reporter under the control of the antioxidant response element (ARE). The monoHAAs generated oxidative stress with a rank order of iodoacetic acid (IAA) > bromoacetic acid (BAA) ≫ chloroacetic acid (CAA); this rank order was observed with other toxicological end points. Toxicogenomic analysis was conducted with a nontransformed human intestinal epithelial cell line (FHs 74 Int). Exposure to the monoHAAs altered the transcription levels of multiple oxidative stress responsive genes, indicating that each exposure generated oxidative stress. The transcriptome profiles showed an increase in thioredoxin reductase 1 (TXNRD1) and sulfiredoxin (SRXN1), suggesting peroxiredoxin proteins had been oxidized during monoHAA exposures. Three possible sources of reactive oxygen species were identified, the hypohalous acid generating peroxidase enzymes lactoperoxidase (LPO) and myeloperoxidase (MPO), nicotinamide adenine dinucleotide phosphate (NADPH)-dependent oxidase 5 (NOX5), and PTGS2 (COX-2) mediated arachidonic acid metabolism. Each monoHAA exposure caused an increase in COX-2 mRNA levels. These data provide a functional association between monoHAA exposure and adverse health outcomes such as oxidative stress, inflammation, and cancer.

  16. Health impacts of long-term exposure to disinfection by-products in drinking water in Europe: HIWATE.

    PubMed

    Nieuwenhuijsen, Mark J; Smith, Rachel; Golfinopoulos, Spyros; Best, Nicky; Bennett, James; Aggazzotti, Gabriella; Righi, Elena; Fantuzzi, Guglielmina; Bucchini, Luca; Cordier, Sylvaine; Villanueva, Cristina M; Moreno, Victor; La Vecchia, Carlo; Bosetti, Cristina; Vartiainen, Terttu; Rautiu, Radu; Toledano, Mireille; Iszatt, Nina; Grazuleviciene, Regina; Kogevinas, Manolis

    2009-06-01

    There appears to be very good epidemiological evidence for a relationship between chlorination by-products, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers, including colorectal cancer appears to be inconclusive and inconsistent. There appears to be some evidence for a relationship between chlorination by-products, as measured by THMs, and small for gestational age (SGA)/intrauterine growth retardation (IUGR) and preterm delivery, but evidence for other outcomes such as low birth weight (LBW), stillbirth, congenital anomalies and semen quality appears to be inconclusive and inconsistent.The overall aim of the HIWATE study is to investigate potential human health risks (e.g. bladder and colorectal cancer, premature births, SGA, semen quality, stillbirth, congenital anomalies) associated with long-term exposure to low levels of disinfectants (such as chlorine) and DBPs occurring in water for human consumption and use in the food industry. The study will comprise risk-benefit analyses including quantitative assessments of risk associated with microbial contamination of drinking water versus chemical risk and will compare alternative treatment options. The outcome will be improved risk assessment and better information for risk management. The work is divided into different topics (exposure assessment, epidemiology, risk assessment and management) and studies.

  17. Limnoithona sinensis as refuge for bacteria: protection from UV radiation and chlorine disinfection in drinking water treatment.

    PubMed

    Lin, Tao; Cai, Bo; Chen, Wei

    2014-11-01

    In this study, we tested the potential of Limnoithona sinensis to provide its attached bacteria refuge against disinfection. The experimental results indicated that in water devoid of zooplankton, both UV radiation and chlorine disinfection significantly decreased the viability of free-living bacteria. In the presence of L. sinensis, however, the attached bacteria could survive and rapidly recover from disinfection. This demonstrated that L. sinensis provided protection from external damage to various aquatic bacteria that were attached to its body. The surviving bacteria remained on L. sinensis after disinfection exposure, which enabled a rapid increase in the bacterial population followed by their subsequent release into the surrounding water. Compared with UV radiation, chlorine disinfection was more effective in terms of inactivating attached bacteria. Both UV radiation and chlorine disinfection had little effect in terms of preventing the spread of undesirable bacteria, due to the incomplete inactivation of the bacteria associated with L. sinensis.

  18. Comparison of Point-of-Use Technologies for Emergency Disinfection of Sewage-Contaminated Drinking Water

    PubMed Central

    McLennan, S. Devin; Peterson, Lauren A.; Rose, Joan B.

    2009-01-01

    Four point-of-use disinfection technologies for treating sewage-contaminated well water were compared. Three systems, based on flocculant-disinfectant packets and N-halamine chlorine and bromine contact disinfectants, provided a range of 4.0 to >6.6 log10 reductions (LR) of naturally occurring fecal indicator and heterotrophic bacteria and a range of 0.9 to >1.9 LR of coliphage. PMID:19767479

  19. [Disinfection and degradation of 2,4-DCP with UV-radiation and on-line ozone in drinking water treatmeant].

    PubMed

    Ma, Xiaomin; Song, Qiang; Hu, Chun; Wang, Yizhong; Qu, Jiuhui

    2002-09-01

    A type reactor with on-line O3 was used to do further research of the disinfection of total bacteria, E. coli and degradation of 2,4-DCP. The result was obtained in the following conditions. Only UV-radiation, O3 applied by other machine and by the reactor itself, and other conditions were changed to study the disinfection and degradation. The result showed the satisfied effect of disinfection and degradation would be achieved by using UV/O3 applied outside and when the flow rate was about 400 L.h-1, on-line O3 could be produced and make high efforts to enhance disinfection and degradation. The method of UV/O3 was a promising technology in the treatment of drinking water.

  20. Biostability and disinfectant by-product formation in drinking water blended with UF-treated filter backwash water.

    PubMed

    Walsh, M E; Gagnon, G A; Alam, Z; Andrews, R C

    2008-04-01

    The overall objective of this study was to investigate the impact of blending membrane-treated water treatment plant (WTP) residuals with plant-filtered water on finished water quality in terms of biostability and disinfectant by-product (DBP) formation. Filter backwash water (FBWW) was treated with a pilot-scale ultrafiltration (UF) membrane to produce permeate that was blended with plant-finished water. The batch studies involved storing samples for a specified time with a disinfectant residual to simulate residence time in the distribution system. Both chlorinated and non-chlorinated FBWW streams were evaluated, and the experimental design incorporated free chlorine, monochloramine, and chlorine dioxide in parallel to a model system that did not receive a disinfectant dose. The results of the study found that blending 10% UF-treated FBWW with plant-filtered water did not have an impact on water biostability as monitored with heterotrophic plate counts (HPCs) or DBP concentrations as monitored by TTHM and HAA5 concentrations. However, the presence of preformed THM and HAA species found in chlorinated FBWW streams may result in higher levels of initial DBP concentrations in blended water matrices, and could have a significant impact on finished water quality in terms of meeting specific DBP guidelines or regulations.

  1. Impacts of drinking water pretreatments on the formation of nitrogenous disinfection by-products.

    PubMed

    Chu, Wenhai; Gao, Naiyun; Deng, Yang; Templeton, Michael R; Yin, Daqiang

    2011-12-01

    The formation of disinfection by-products (DBPs), including both nitrogenous DBPs (N-DBPs) and carbonaceous DBPs (C-DBPs), was investigated by analyzing chlorinated water samples following the application of three pretreatment processes: (i) powdered activated carbon (PAC) adsorption; (ii) KMnO(4) oxidation and (iii) biological contact oxidation (BCO), coupled with conventional water treatment processes. PAC adsorption can remove effectively the precursors of chloroform (42.7%), dichloroacetonitrile (28.6%), dichloroacetamide (DCAcAm) (27.2%) and trichloronitromethane (35.7%), which were higher than that pretreated by KMnO(4) oxidation and/or BCO process. The removal efficiency of dissolved organic carbon by BCO process (76.5%)--was superior to that by PAC adsorption (69.9%) and KMnO(4) oxidation (61.4%). However, BCO increased the dissolved organic nitrogen (DON) concentration which caused more N-DBPs to be formed during subsequent chlorination. Soluble microbial products including numerous DON compounds were produced in the BCO process and were observed to play an essential role in the formation of DCAcAm in particular. PMID:22014706

  2. Disinfection of model indicator organisms in a drinking water pilot plant by using PEROXONE.

    PubMed

    Wolfe, R L; Stewart, M H; Liang, S; McGuire, M J

    1989-09-01

    at an applied ozone dosage of 2.0 mg/liter (and a 4-min contact time) when the H2O2/O3 ratio was less than or equal to 0.5. Comparative disinfection experiments indicated that free chlorine was the most potent bactericidal agent, followed (in descending order of effectiveness) by ozone, PEROXONE, and chloramines. These results indicate that the PEROXONE process must be optimized for each source water to achieve microbicidal effectiveness.

  3. Disinfection of model indicator organisms in a drinking water pilot plant by using PEROXONE.

    PubMed Central

    Wolfe, R L; Stewart, M H; Liang, S; McGuire, M J

    1989-01-01

    at an applied ozone dosage of 2.0 mg/liter (and a 4-min contact time) when the H2O2/O3 ratio was less than or equal to 0.5. Comparative disinfection experiments indicated that free chlorine was the most potent bactericidal agent, followed (in descending order of effectiveness) by ozone, PEROXONE, and chloramines. These results indicate that the PEROXONE process must be optimized for each source water to achieve microbicidal effectiveness. PMID:2679383

  4. MONITORING FOR AEROMONAS SPECIES AFTER TREATMENT WITH COMMON DRINKING WATER DISINFECTANTS

    EPA Science Inventory

    The sensitivity of Aeromonas spp. To free chlorine, chloramine and ultraviolet (UV) disinfection was determined. Aeromonas hydrophila is a contaminant listed on the USEPA's 1998 Contaminant Candidate List (CCL). Experiments using free chlorine indicated that the Aeromonas spp. ...

  5. Seasonal evaluation of the presence of 46 disinfection by-products throughout a drinking water treatment plant.

    PubMed

    Serrano, Maria; Montesinos, Isabel; Cardador, M J; Silva, Manuel; Gallego, Mercedes

    2015-06-01

    In this work, we studied a total of 46 regulated and non-regulated disinfection by-products (DBPs) including 10 trihalomethanes (THMs), 13 haloacetic acids (HAAs), 6 halonitromethanes (HNMs), 6 haloacetonitriles (HANs) and 11 aldehydes at different points in a drinking water treatment plant (DWTP) and its distribution network. Determining an increased number of compounds and using accurate, sensitive analytical methodologies for new DBPs can be useful to overcome some challenges encountered in the comprehensive assessment of the quality and safety of drinking water. This paper provides a detailed picture of the spatial and seasonal variability of DBP concentrations from raw water to distribution network. Samples were collected on a monthly basis at seven different points in the four seasons of a year to acquire robust data for DBPs and supplementary quality-related water parameters. Only 5 aldehydes and 2 HAAs were found in raw water. Chlorine dioxide caused the formation of 3 new aldehydes (benzaldehyde included), 5 HAAs and chloroform. The concentrations of DBPs present in raw water were up to 6 times higher in the warmer seasons (spring and summer). The sedimentation process further increased their concentrations and caused the formation of three new ones. Sand filtration substantially removed aldehydes and HAAs (15-50%), but increased the levels of THMs, HNMs and HANs by up to 70%. Chloramination raised the levels of 8 aldehydes and 7 HAAs; also, it caused the formation of monoiodoacetic acid, dibromochloromethane, dichloroiodomethane and bromochloroacetonitrile. Therefore, this treatment increases the levels of existing DBPs and leads to the formation of new ones to a greater extent than does chlorine dioxide. Except for 5 aldehydes, the 23 DBPs encountered at the DWTP exit were found at increased concentrations in the warmer seasons (HAAs by about 50% and THMs by 350%).

  6. Seasonal variation in drinking water concentrations of disinfection by-products in IZMIR and associated human health risks.

    PubMed

    Baytak, Derya; Sofuoglu, Aysun; Inal, Fikret; Sofuoglu, Sait C

    2008-12-15

    Seasonal variation in concentrations of two different disinfection by-product groups, trihalomethanes (THMs) and haloacetonitriles (HANs), was investigated in tap water samples collected from five sampling points (one groundwater and four surface water sources) in Izmir, Turkey. Estimates of previously published carcinogenic and non-carcinogenic risks through oral exposure to THMs were re-evaluated using a probabilistic approach that took the seasonal concentration variation into account. Chloroform, bromoform, dibromochloromethane and dichloroacetonitrile were the most frequently detected compounds. Among these, chloroform was detected with the highest concentrations ranging from 0.03 to 98.4 microg/L. In tap water, at the groundwater supplied sampling point, brominated species, bromoform and dibromoacetonitrile, were detected at the highest levels most probably due to bromide ion intrusion from seawater. The highest total THM and total HAN concentrations were detected in spring while the lowest in summer and fall. The annual average total THM concentration measured at one of the surface water supplied sampling points exceeded the USEPA's limit of 80 microg/L. While all non-carcinogenic risks due to exposure to THMs in Izmir drinking water were negligible, carcinogenic risk levels associated with bromodichloromethane and dibromochloromethane were higher than one in million.

  7. Disinfection byproduct formation during biofiltration cycle: Implications for drinking water production.

    PubMed

    Delatolla, R; Séguin, C; Springthorpe, S; Gorman, E; Campbell, A; Douglas, I

    2015-10-01

    The goal of this study was to investigate the potential of biofiltration to reduce the formation potential of disinfection byproducts (DBPs). Particularly, the work investigates the effect of the duration of the filter cycle on the formation potential of total trihalomethanes (TTHM) and five species of haloacetic acids (HAA5), dissolved oxygen (DO), organic carbon, nitrogen and total phosphorous concentrations along with biofilm coverage of the filter media and biomass viability of the attached cells. The study was conducted on a full-scale biologically active filter, with anthracite and sand media, at the Britannia water treatment plant (WTP), located in Ottawa, Ontario, Canada. The formation potential of both TTHMs and HAA5s decreased due to biofiltration. However the lowest formation potentials for both groups of DBPs and or their precursors were observed immediately following a backwash event. Hence, the highest percent removal of DBPs was observed during the early stages of the biofiltration cycle, which suggests that a higher frequency of backwashing will reduce the formation of DBPs. Variable pressure scanning electron microscopy (VPSEM) analysis shows that biofilm coverage of anthracite and sand media increases as the filtration cycle progressed, while biomass viability analysis demonstrates that the percentage of cells attached to the anthracite and sand media also increases as the filtration cycle progresses. These results suggest that the development and growth of biofilm on the filters increases the DPB formation potential.

  8. Effect of ozonation and UV irradiation with direct filtration on disinfection and disinfection by-product precursors in drinking water treatment.

    PubMed

    Amirsardari, Y; Yu, Q; Willams, P

    2001-09-01

    Pilot plant studies were conducted to evaluate the effect of pre-ozonation and ultraviolet irradiation on disinfection, disinfection by-product precursors and water quality in a direct filtration water treatment system. Disinfection parameters including total coliforms, faecal coliforms and heterotrophic plate count were investigated. Total organic carbon (TOC), trihalomethanes (THMs), total organic halides (TOX), filtered water turbidity and colour were also evaluated. It was found that advanced pre-oxidation processes (ozonation and UV irradiation) significantly increase the level of disinfection of raw water. Removal of total trihalomethanes and total organic halides precursors improved with ozonation and UV irradiation, compared to no oxidation treatment in direct filtration and/or in conventional water treatment. All coliforms (total and faecal) were completely destroyed by ozonation alone, and also with ozonation in conjunction with UV irradiation. However, the heterotrophic plate count was not significantly reduced at an ozone residual concentration of 0.1 mg l(-1). This suggests that disinfection efficiency is strongly influenced by competition reactions of organic and inorganic compounds with ozone. Precursors of total trihalomethanes and total organic halides were reduced by 90% and 98%, respectively, with advanced pre-oxidation processes. Water quality parameters were improved by the pre-ozonation and UV irradiation treatment system.

  9. Reactions of phenylurea compounds with aqueous chlorine: Implications for herbicide transformation during drinking water disinfection.

    PubMed

    Chusaksri, Sarinma; Sutthivaiyakit, Somyote; Sedlak, David L; Sutthivaiyakit, Pakawadee

    2012-03-30

    Phenylurea herbicides have been known to contaminate surface waters serving as potable supplies. To access the potential for transformation of these compounds during drinking water treatment, reactions of phenylurea compounds with aqueous chlorine at different pHs were investigated. The effect of substitution at the amino-N on the rate of transformation depends upon pH. Under acidic conditions, all of the phenylurea studied except 3,4-dichloro-3'-N-methylphenylurea (3,4-DCMPU) exhibited third-order kinetics, second order with respect to chlorine and first order with respect to phenylurea, while the reactions of 3,4-DCMPU were first order with respect to both chlorine and the organic compound. Under neutral and alkaline conditions, all compounds exhibited second-order kinetics that was first order with respect to chlorine and the organic compound. Apparent second-order rate constants at 25°C and pH 7 were 0.76 ± 0.16, 0.52 ± 0.11, 0.39 ± 0.02, 0.27 ± 0.04 and 0.23 ± 0.05 M(-1)s(-1) for phenylurea, 3, 4-dichlorophenylurea, 3, 4-DCMPU, metoxuron and monuron, respectively. Studies of the chlorination products, monitored by LC/MS/MS, under different pH values indicated the reaction to take place at both N atoms and also at ortho- and para- positions of the phenylurea aromatic group. The main chlorinating species were found to be different in different pH ranges. Under conditions typically encountered in drinking water treatment systems, transformation of these compounds by chlorine will be incomplete.

  10. [Effects of bromide and ferric ions on formation of tri-halomethanes during disinfection of drinking water by chlorine].

    PubMed

    Zhu, Zhi-Liang; Wang, Jing; Ge, Yuan-Xin; Ma, Hong-Mei; Zhao, Jian-Fu

    2007-06-01

    Effects of bromide and ferric ions on the formation and distribution of tri-halomethanes (THMs) have been investigated. As disinfection by-product (DBP) model precursors of natural water, humic acid solutions were used and a series of experiments were conducted. The results showed that bromide in this reaction system not only contributed to the increase of brominated species, but also the total tri-halomethanes. When the concentration of Br(-) was 1.0 mg/L, the total amount of produced THMs reached to 270% of that without bromide ions. In the presence of bromide, ferric ions decreased the production of THMs at pH 6, but increased the production of THMs at pH 8, especially for the amount of tri-bromomethanes. When the concentration of Fe3+ was 5 mg/L, the amount of produced tri-bromomethanes had an increment of 54% (from 51.7 microg/L to 79.4 microg/L), and the total amount of THMs increased from 113.49 microg/L to 162.09 microg/L. Bromide ions had a significant effect on carcinogenicity risk in disinfection of drinking water by chlorine, and the co-existence of ferric ion and bromide in alkalescent environment can result in the biggest challenge on carcinogenicity risk. Under the condition of 0.2 mg/L Br(-), 5 mg/L Fe3+ and pH 6, the carcinogenicity risk increased 2.5 times than that without Br(-) and Fe3+, and much higher increment of 5.1 times appeared when pH was 8.

  11. Fingerprinting the reactive toxicity pathways of 50 drinking water disinfection by-products.

    PubMed

    Stalter, Daniel; O'Malley, Elissa; von Gunten, Urs; Escher, Beate I

    2016-03-15

    A set of nine in vitro cellular bioassays indicative of different stages of the cellular toxicity pathway was applied to 50 disinfection by-products (DBPs) to obtain a better understanding of the commonalities and differences in the molecular mechanisms of reactive toxicity of DBPs. An Eschericia coli test battery revealed reactivity towards proteins/peptides for 64% of the compounds. 98% activated the NRf2-mediated oxidative stress response and 68% induced an adaptive stress response to genotoxic effects as indicated by the activation of the tumor suppressor protein p53. All DBPs reactive towards DNA in the E. coli assay and activating p53 also induced oxidative stress, confirming earlier studies that the latter could trigger DBP's carcinogenicity. The energy of the lowest unoccupied molecular orbital ELUMO as reactivity descriptor was linearly correlated with oxidative stress induction for trihalomethanes (r(2)=0.98) and haloacetamides (r(2)=0.58), indicating that potency of these DBPs is connected to electrophilicity. However, the descriptive power was poor for haloacetic acids (HAAs) and haloacetonitriles (r(2) (<) 0.06). For HAAs, we additionally accounted for speciation by including the acidity constant with ELUMO in a two-parameter multiple linear regression model. This increased r(2) to >0.80, indicating that HAAs' potency is connected to both, electrophilicity and speciation. Based on the activation of oxidative stress response and the soft electrophilic character of most tested DBPs we hypothesize that indirect genotoxicity-e.g., through oxidative stress induction and/or enzyme inhibition-is more plausible than direct DNA damage for most investigated DBPs. The results provide not only a mechanistic understanding of the cellular effects of DBPs but the effect concentrations may also serve to evaluate mixture effects of DBPs in water samples. PMID:26773486

  12. Fingerprinting the reactive toxicity pathways of 50 drinking water disinfection by-products.

    PubMed

    Stalter, Daniel; O'Malley, Elissa; von Gunten, Urs; Escher, Beate I

    2016-03-15

    A set of nine in vitro cellular bioassays indicative of different stages of the cellular toxicity pathway was applied to 50 disinfection by-products (DBPs) to obtain a better understanding of the commonalities and differences in the molecular mechanisms of reactive toxicity of DBPs. An Eschericia coli test battery revealed reactivity towards proteins/peptides for 64% of the compounds. 98% activated the NRf2-mediated oxidative stress response and 68% induced an adaptive stress response to genotoxic effects as indicated by the activation of the tumor suppressor protein p53. All DBPs reactive towards DNA in the E. coli assay and activating p53 also induced oxidative stress, confirming earlier studies that the latter could trigger DBP's carcinogenicity. The energy of the lowest unoccupied molecular orbital ELUMO as reactivity descriptor was linearly correlated with oxidative stress induction for trihalomethanes (r(2)=0.98) and haloacetamides (r(2)=0.58), indicating that potency of these DBPs is connected to electrophilicity. However, the descriptive power was poor for haloacetic acids (HAAs) and haloacetonitriles (r(2) (<) 0.06). For HAAs, we additionally accounted for speciation by including the acidity constant with ELUMO in a two-parameter multiple linear regression model. This increased r(2) to >0.80, indicating that HAAs' potency is connected to both, electrophilicity and speciation. Based on the activation of oxidative stress response and the soft electrophilic character of most tested DBPs we hypothesize that indirect genotoxicity-e.g., through oxidative stress induction and/or enzyme inhibition-is more plausible than direct DNA damage for most investigated DBPs. The results provide not only a mechanistic understanding of the cellular effects of DBPs but the effect concentrations may also serve to evaluate mixture effects of DBPs in water samples.

  13. Evaluating the similarity of complex drinking-water disinfection by-product mixtures: overview of the issues.

    PubMed

    Rice, Glenn E; Teuschler, Linda K; Bull, Richard J; Simmons, Jane E; Feder, Paul I

    2009-01-01

    Humans are exposed daily to complex mixtures of environmental chemical contaminants, which arise as releases from sources such as engineering procedures, degradation processes, and emissions from mobile or stationary sources. When dose-response data are available for the actual environmental mixture to which individuals are exposed (i.e., the mixture of concern), these data provide the best information for dose-response assessment of the mixture. When suitable data on the mixture itself are not available, surrogate data might be used from a sufficiently similar mixture or a group of similar mixtures. Consequently, the determination of whether the mixture of concern is "sufficiently similar" to a tested mixture or a group of tested mixtures is central to the use of whole mixture methods. This article provides an overview for a series of companion articles whose purpose is to develop a set of biostatistical, chemical, and toxicological criteria and approaches for evaluating the similarity of drinking-water disinfection by-product (DBPs) complex mixtures. Together, the five articles in this series serve as a case study whose techniques will be relevant to assessing similarity for other classes of complex mixtures of environmental chemicals. Schenck et al. (2009) describe the chemistry and mutagenicity of a set of DBP mixtures concentrated from five different drinking-water treatment plants. Bull et al. (2009a, 2009b) describe how the variables that impact the formation of DBP affect the chemical composition and, subsequently, the expected toxicity of the mixture. Feder et al. (2009a, 2009b) evaluate the similarity of DBP mixture concentrates by applying two biostatistical approaches, principal components analysis, and a nonparametric "bootstrap" analysis. Important factors for determining sufficient similarity of DBP mixtures found in this research include disinfectant used; source water characteristics, including the concentrations of bromide and total organic carbon

  14. Effect of hypochlorite-based disinfectants on inactivation of murine norovirus and attempt to eliminate or prevent infection in mice by addition to drinking water.

    PubMed

    Takimoto, Kazuhiro; Taharaguchi, Motoko; Sakai, Koji; Takagi, Hirotaka; Tohya, Yukinobu; Yamada, Yasuko K

    2013-01-01

    We evaluated the in vitro efficacy of weak acid hypochlorous solution (WAHS) against murine norovirus (MNV) by plaque assay and compared the efficacy with diluted NaOCl (Purelox) and 70% ethanol. WAHS was as effective as 70% ethanol and diluted Purelox for 0.5-min reactions. For 0.5-min reactions in the presence of mouse feces emulsion, the efficacy of WHAS and 1:600 diluted Purelox was decreased, reducing the virus titers by 2.3 and 2.6 log10, respectively, while 70% ethanol reduced the titer by more than 5 log10. However, WAHS showed more than 5 log10 reductions for the 5-min reaction even in the presence of feces emulsion. Since WAHS showed enough efficacy in inactivating MNV in vitro, we tried to eliminate MNV from MNV-infected mice by substituting WAHS for their drinking water. However, MNV was found to be positive in feces of mice drinking WAHS by an RT-nested PCR and plaque assay. To investigate whether hypochlorite-based disinfectants could prevent infection of a mouse with MNV, WAHS or 1:6,000 diluted Purelox was substituted for the drinking water of mice for 2 or 4 weeks, and then the mice were placed in a cage with an MNV-infected mouse. The supply of disinfectants was continued after cohabitation, but MNV was detected in the feces of all the mice at 1 week after cohabitation. In this study, we tried to eliminate and prevent MNV infection from mice by supplying hypochlorite-based disinfectants as an easy and low-cost method. Unfortunately, drinking disinfectants was ineffective, so it is important to keep the facility environment clean by use of effective disinfectants. Also, animals introduced into facilities should be tested as MNV free by quarantine and periodically confirmed as MNV free by microbiological monitoring. PMID:23903059

  15. Effect of hypochlorite-based disinfectants on inactivation of murine norovirus and attempt to eliminate or prevent infection in mice by addition to drinking water.

    PubMed

    Takimoto, Kazuhiro; Taharaguchi, Motoko; Sakai, Koji; Takagi, Hirotaka; Tohya, Yukinobu; Yamada, Yasuko K

    2013-01-01

    We evaluated the in vitro efficacy of weak acid hypochlorous solution (WAHS) against murine norovirus (MNV) by plaque assay and compared the efficacy with diluted NaOCl (Purelox) and 70% ethanol. WAHS was as effective as 70% ethanol and diluted Purelox for 0.5-min reactions. For 0.5-min reactions in the presence of mouse feces emulsion, the efficacy of WHAS and 1:600 diluted Purelox was decreased, reducing the virus titers by 2.3 and 2.6 log10, respectively, while 70% ethanol reduced the titer by more than 5 log10. However, WAHS showed more than 5 log10 reductions for the 5-min reaction even in the presence of feces emulsion. Since WAHS showed enough efficacy in inactivating MNV in vitro, we tried to eliminate MNV from MNV-infected mice by substituting WAHS for their drinking water. However, MNV was found to be positive in feces of mice drinking WAHS by an RT-nested PCR and plaque assay. To investigate whether hypochlorite-based disinfectants could prevent infection of a mouse with MNV, WAHS or 1:6,000 diluted Purelox was substituted for the drinking water of mice for 2 or 4 weeks, and then the mice were placed in a cage with an MNV-infected mouse. The supply of disinfectants was continued after cohabitation, but MNV was detected in the feces of all the mice at 1 week after cohabitation. In this study, we tried to eliminate and prevent MNV infection from mice by supplying hypochlorite-based disinfectants as an easy and low-cost method. Unfortunately, drinking disinfectants was ineffective, so it is important to keep the facility environment clean by use of effective disinfectants. Also, animals introduced into facilities should be tested as MNV free by quarantine and periodically confirmed as MNV free by microbiological monitoring.

  16. Spatio-temporal variability of non-regulated disinfection by-products within a drinking water distribution network.

    PubMed

    Mercier Shanks, Catherine; Sérodes, Jean-Baptiste; Rodriguez, Manuel J

    2013-06-01

    The non-regulated disinfection by-products (NrDBP) targeted in this study include four haloacetonitriles (trichloroacetonitrile (TCAN); dichloroacetonitrile (DCAN); bromochloroacetonitrile (BCAN) and dibromoacetonitrile (DBAN)); one halonitromethane (trichloronitromethane, better known under the name chloropicrin (CPK)); and two haloketones (1,1-dichloro-2-propanone (11DCPone) and 1,1,1-trichloro-2-propanone (111TCPone)). This study provides a detailed picture of the spatial and temporal variability of these NrDBP concentrations throughout a drinking water distribution system located in a region with major seasonal climate variations. The results obtained show that the concentrations of the investigated NrDBPs varied significantly according to time and location. The average concentrations of TCAN, DCAN, CKP and 111TCPone were significantly higher in summer. Surprisingly, the average concentrations of 11DCPone were significantly higher in winter. For BCAN and DBAN, the average concentrations observed in winter were higher, but not in a statistically significant way. On the other hand, the four HANs, CPK and 111TCPone generally had spatial profiles involving an increase of the concentrations along the network according to increasing water residence times, whereas 11DCPone overall had a profile where concentrations increased at the beginning of the network, followed by a drop in the concentrations towards the ends of the network. In spite of certain disparities in the individual spatio-temporal variation profiles, strong correlations were generally observed between NrDBPs, and trihalomethanes (THMs) and haloacetic acids (HAAs). Therefore, THMs and HAAs could be good statistical indicators of the presence of NrDBPs in the drinking water of the system under study.

  17. Spatio-temporal variability of non-regulated disinfection by-products within a drinking water distribution network.

    PubMed

    Mercier Shanks, Catherine; Sérodes, Jean-Baptiste; Rodriguez, Manuel J

    2013-06-01

    The non-regulated disinfection by-products (NrDBP) targeted in this study include four haloacetonitriles (trichloroacetonitrile (TCAN); dichloroacetonitrile (DCAN); bromochloroacetonitrile (BCAN) and dibromoacetonitrile (DBAN)); one halonitromethane (trichloronitromethane, better known under the name chloropicrin (CPK)); and two haloketones (1,1-dichloro-2-propanone (11DCPone) and 1,1,1-trichloro-2-propanone (111TCPone)). This study provides a detailed picture of the spatial and temporal variability of these NrDBP concentrations throughout a drinking water distribution system located in a region with major seasonal climate variations. The results obtained show that the concentrations of the investigated NrDBPs varied significantly according to time and location. The average concentrations of TCAN, DCAN, CKP and 111TCPone were significantly higher in summer. Surprisingly, the average concentrations of 11DCPone were significantly higher in winter. For BCAN and DBAN, the average concentrations observed in winter were higher, but not in a statistically significant way. On the other hand, the four HANs, CPK and 111TCPone generally had spatial profiles involving an increase of the concentrations along the network according to increasing water residence times, whereas 11DCPone overall had a profile where concentrations increased at the beginning of the network, followed by a drop in the concentrations towards the ends of the network. In spite of certain disparities in the individual spatio-temporal variation profiles, strong correlations were generally observed between NrDBPs, and trihalomethanes (THMs) and haloacetic acids (HAAs). Therefore, THMs and HAAs could be good statistical indicators of the presence of NrDBPs in the drinking water of the system under study. PMID:23582352

  18. Lead and Drinking Water from Private Wells

    MedlinePlus

    ... Nutrition Camping, Hiking, Travel Drinking Water Treatment and Sanitation for Backcountry & Travel Use Emergency Disinfection of Drinking ... Uses of Water WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related Hygiene Related Sites Get Email Updates ...

  19. Giardia and Drinking Water from Private Wells

    MedlinePlus

    ... Nutrition Camping, Hiking, Travel Drinking Water Treatment and Sanitation for Backcountry & Travel Use Emergency Disinfection of Drinking ... Uses of Water WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related Hygiene Related Sites Get Email Updates ...

  20. Effect of temperature and disinfection strategies on ammonia-oxidizing bacteria in a bench-scale drinking water distribution system.

    PubMed

    Pintar, Katarina D M; Slawson, Robin M

    2003-04-01

    The establishment of ammonia-oxidizing bacteria (AOB), a group of autotrophic microorganisms responsible for nitrification in chloraminated distribution systems, was studied in a bench-scale distribution system. The potential significance of temperature and disinfectant residual associated with chloramination in full-scale drinking water distribution systems was assessed. Biofilm development was primarily monitored using AOB abundance and nitrite concentrations. The bench-scale system was initially operated under typical North American summer (22 degrees C) and fall (12 degrees C) temperatures, representing optimal and less optimal growth ranges for these microorganisms. Additional experimentation investigated AOB establishment at a suboptimal winter distribution system temperature of 6 degrees C. The effect of chloramine residual on AOB establishment was studied at higher (0.2-0.6mg/L) and lower (0.05-0.1mg/L) ranges, using a 3:1 (w/w) chlorine:ammonia dosing ratio. Conditions were selected to represent those typically found in a North American distribution system, in areas of low flow and longer retention times, respectively. Finally, the effect of a free chlorine residual on an established nitrifying biofilm was briefly examined. Results clearly indicate that AOB development occurs at all examined temperatures, as well as at selected monochloramine residuals. The maintenance of a disinfectant residual was difficult at times, but was more inhibitory to the nitrifying biofilm than the lower temperature. It can be concluded from the data that nitrification may not be adequately inhibited during the winter months, which may result in more advanced stages of nitrification the following season. Free chlorination can be effective in controlling AOB activity in the short term, but may not prevent reestablishment of a nitrifying biofilm upon return to chloramination.

  1. DETERMINATION OF NEW CARBONYL-CONTAINING DISINFECTION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Only a subset of all disinfection by-products were targeted for an intense occurrence study during the Information Collection Rule. Among 50 additional compounds selected for study because of their potential for significant toxicity, a group of carbonyl-containing compounds is be...

  2. [Degradation Kinetics and Formation of Disinfection By-products During Linuron Chlorination in Drinking Water].

    PubMed

    Ling, Xiao; Hu, Chen-yan; Cheng, Ming; Gu, Jian

    2015-05-01

    Chlorination degradation of linuron was studied using the common disinfectant sodium hypochlorite, the effects of chlorine dosage, pH value, bromine ion concentrationand temperature were systematically investigated, and the formation characteristics of disinfection by-products (DBPs) during the chlorination reaction was analyzed. The results showed that the chlorination degradation kinetics of linuron by sodium hypochlorite could be well described by the second-order kinetic model. Moreover, pH values had a great impact on the degradation reaction, and the rate constant reached the maximum level at pH 7, and the base elementary reaction rate constants of HOCl and OCl- with linuron were 4.84 x 10(2) L · (mol · h)(-1) and 3.80 x 10(2) L · (mol · h)(-1), respectively. The reaction rate decreased with the addition of bromide ion and increased with increasing temperature. Furthermore, many kinds of disinfection by- products were produced during the chlorination degradation of linuron, including CF, DCAN, TCNM and halogen acetone. Under conditions of different solution pH and different bromide ion concentrations, there would be significant difference in the types and concentrations of disinfection by-products.

  3. Field study on evaluation of the efficacy and usability of two disinfectants for drinking water treatment at small cattle breeders and dairy cattle farms.

    PubMed

    Mohammed, Asmaa N

    2016-03-01

    The hygienic quality of drinking water for cattle originated from different sources together with the efficacy and usability of two types of disinfectants against waterborne pathogens were assessed for small cattle breeders and dairy cattle farms. A total of 120 drinking water samples were collected from water troughs representing three different water sources commonly used for cattle drinking (tap, underground and surface water; n = 65, 25, and 30, respectively). Collected samples were cultured for isolation and identification of pathogenic bacteria using serological techniques and PCR. The bactericidal efficacy of the disinfectants, sodium dichloroisocyanurate (NaDCC) and hydrogen peroxide (H2O2) 50%, at different concentrations were evaluated by the determination of total viable and coliform counts of water prior and postwater treatment. In small cattle breeders, Escherichia coli was the most prevalent bacterial isolates from surface water (56.7%) followed by Staphylococcus aureus (36.7%), Salmonella spp. (26.7%), Streptococcus faecalis (23.3%), Shigella flexneri (16.7%), Proteus spp. (16.7%), and Klebsiella pneumonae (10.0 %) at X(2) = 9, P ≤ 0.01. Prior to the use of disinfectants, the averages of total bacterial and coliform counts were the highest in surface water (3.56 × 10(7), 240.0, and 38.0 CFU/100 ml, respectively). It has been found that hydrogen peroxide 50% at a concentration of 35 mg/l had a lethal effect (100 %) on indicator microorganisms compared with NaDCC at concentration of 2 mg/l. In conclusion, the higher bacterial contaminants in drinking water were found in surface water followed by tap water, particularly for small cattle breeders. Therefore, the usage of more hygienic water troughs with their regular treatment by hydrogen peroxide 50% at concentration of 35 mg/l is highly recommended to control waterborne bacteria and consequently improve and maintain the animal health.

  4. Field study on evaluation of the efficacy and usability of two disinfectants for drinking water treatment at small cattle breeders and dairy cattle farms.

    PubMed

    Mohammed, Asmaa N

    2016-03-01

    The hygienic quality of drinking water for cattle originated from different sources together with the efficacy and usability of two types of disinfectants against waterborne pathogens were assessed for small cattle breeders and dairy cattle farms. A total of 120 drinking water samples were collected from water troughs representing three different water sources commonly used for cattle drinking (tap, underground and surface water; n = 65, 25, and 30, respectively). Collected samples were cultured for isolation and identification of pathogenic bacteria using serological techniques and PCR. The bactericidal efficacy of the disinfectants, sodium dichloroisocyanurate (NaDCC) and hydrogen peroxide (H2O2) 50%, at different concentrations were evaluated by the determination of total viable and coliform counts of water prior and postwater treatment. In small cattle breeders, Escherichia coli was the most prevalent bacterial isolates from surface water (56.7%) followed by Staphylococcus aureus (36.7%), Salmonella spp. (26.7%), Streptococcus faecalis (23.3%), Shigella flexneri (16.7%), Proteus spp. (16.7%), and Klebsiella pneumonae (10.0 %) at X(2) = 9, P ≤ 0.01. Prior to the use of disinfectants, the averages of total bacterial and coliform counts were the highest in surface water (3.56 × 10(7), 240.0, and 38.0 CFU/100 ml, respectively). It has been found that hydrogen peroxide 50% at a concentration of 35 mg/l had a lethal effect (100 %) on indicator microorganisms compared with NaDCC at concentration of 2 mg/l. In conclusion, the higher bacterial contaminants in drinking water were found in surface water followed by tap water, particularly for small cattle breeders. Therefore, the usage of more hygienic water troughs with their regular treatment by hydrogen peroxide 50% at concentration of 35 mg/l is highly recommended to control waterborne bacteria and consequently improve and maintain the animal health. PMID:26861741

  5. Multi-species biofilms defined from drinking water microorganisms provide increased protection against chlorine disinfection.

    PubMed

    Schwering, Monika; Song, Joanna; Louie, Marie; Turner, Raymond J; Ceri, Howard

    2013-09-01

    A model biofilm, formed of multiple species from environmental drinking water, including opportunistic pathogens, was created to explore the tolerance of multi-species biofilms to chlorine levels typical of water-distribution systems. All species, when grown planktonically, were killed by concentrations of chlorine within the World Health Organization guidelines (0.2-5.0 mg l(-1)). Higher concentrations (1.6-40-fold) of chlorine were required to eradicate biofilm populations of these strains, ~70% of biofilms tested were not eradicated by 5.0 mg l(-1) chlorine. Pathogenic bacteria within the model multi-species biofilms had an even more substantial increase in chlorine tolerance; on average ~700-1100 mg l(-1) chlorine was required to eliminate pathogens from the biofilm, 50-300-fold higher than for biofilms comprising single species. Confocal laser scanning microscopy of biofilms showed distinct 3D structures and multiple cell morphologies and arrangements. Overall, this study showed a substantial increase in the chlorine tolerance of individual species with co-colonization in a multi-species biofilm that was far beyond that expected as a result of biofilm growth on its own.

  6. Comet and micronucleus assays in zebra mussel cells for genotoxicity assessment of surface drinking water treated with three different disinfectants.

    PubMed

    Bolognesi, Claudia; Buschini, Annamaria; Branchi, Elisa; Carboni, Pamela; Furlini, Mariangela; Martino, Anna; Monteverde, Martino; Poli, Paola; Rossi, Carlo

    2004-10-15

    The aim of this research was to study the influence of classic (sodium hypochlorite and chlorine dioxide) and alternative (peracetic acid [PAA]) disinfectants on the formation of mutagens in surface waters used for human consumption. For this proposal, in vivo genotoxicity tests (Comet and micronucleus assay) were performed in an experimental pilot plant set up near Lake Trasimeno (Central Italy). The effects were detected in different tissues (haemocytes for the Comet assay and gills for the micronucleus test [MN]) of Dreissena polymorpha exposed in experimental basins supplied with lake water with/without the different disinfectants. Specimen collection was performed before disinfectant input for both tests and after the start of disinfection (3 h and 20 days for the Comet assay and 10 and 20 days for micronucleus test, respectively) to assess short- and long- term exposure effects during three sampling campaigns (October 2000, February 2001, and June 2001). Seasonal differences in baseline levels of DNA migration and micronucleus frequency were observed. Raw water quality modulation on disinfection by-product formation was shown. The results of the micronucleus and Comet assays on zebra mussel cells after in situ exposure to water disinfected with the two chlorinated compounds clearly indicate DNA/by-product interaction. PAA did not induce either clastogenic/aneugenic effects or DNA damage on this bioindicator. PMID:15364524

  7. Solar and photocatalytic disinfection of protozoan, fungal and bacterial microbes in drinking water.

    PubMed

    Lonnen, J; Kilvington, S; Kehoe, S C; Al-Touati, F; McGuigan, K G

    2005-03-01

    The ability of solar disinfection (SODIS) and solar photocatalytic (TiO(2)) disinfection (SPC-DIS) batch-process reactors to inactivate waterborne protozoan, fungal and bacterial microbes was evaluated. After 8 h simulated solar exposure (870 W/m(2) in the 300 nm-10 microm range, 200 W/m(2) in the 300-400 nm UV range), both SPC-DIS and SODIS achieved at least a 4 log unit reduction in viability against protozoa (the trophozoite stage of Acanthamoeba polyphaga), fungi (Candida albicans, Fusarium solani) and bacteria (Pseudomonas aeruginosa, Escherichia coli). A reduction of only 1.7 log units was recorded for spores of Bacillus subtilis. Both SODIS and SPC-DIS were ineffective against the cyst stage of A. polyphaga.

  8. Human health risk analysis from disinfection by-products (DBPs) in drinking and bathing water of some Indian cities

    PubMed Central

    2014-01-01

    Background Human health risk assessment from exposure to disinfection by-products (DBPs) during drinking and bathing water vary from country to country as per life expectancy, body mass index, water consumption pattern and individual concentration of DBPs component, etc. Methods Present study considered average direct water intake per person for adult males and females as 4 & 3 L/day, respectively as per Indian literature for risk evaluation from another component of pollutant. While other important factor like average life expectancy, body weight & body surface area for male and female were considered 64 & 67 years, 51.9 & 45.4 Kg and 1.54 & 1.38 m2 respectively as per Indian Council of Medical Research and WHO report. The corresponding lifetime cancer risk of the formed THMs to human beings was estimated by the USEPA and IRIS method as per Indian population. Results The total cancer risk reached 8.99 E-04 and 8.92 E-04 for males and females, respectively, the highest risk from THMs seems to be from the inhalation route followed by ingestion and dermal contacts. Conclusions The multipath way evaluations of lifetime cancer risks for THMs exposure through ingestion, dermal absorption, and inhalation exposure were examined at the highest degree of danger. Results reveals that water containing THMs of the selected water treatment plant of the eastern part of India was unsafe in terms of risk evaluation through inhalation and ingestion, while dermal route of risk was found very close to permissible limit of USEPA. Sensitivity analysis shows that every input parameter is sole responsible for total risk potential, whereas exposure duration playing important role for estimation of total risk. PMID:24872885

  9. Pyruvate remediation of cell stress and genotoxicity induced by haloacetic acid drinking water disinfection by-products.

    PubMed

    Dad, Azra; Jeong, Clara H; Pals, Justin A; Wagner, Elizabeth D; Plewa, Michael J

    2013-10-01

    Monohaloacetic acids (monoHAAs) are a major class of drinking water disinfection by-products (DBPs) and are cytotoxic, genotoxic, mutagenic, and teratogenic. We propose a model of toxic action based on monoHAA-mediated inhibition of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a target cytosolic enzyme. This model predicts that GAPDH inhibition by the monoHAAs will lead to a severe reduction of cellular ATP levels and repress the generation of pyruvate. A loss of pyruvate will lead to mitochondrial stress and genomic DNA damage. We found a concentration-dependent reduction of ATP in Chinese hamster ovary cells after monoHAA treatment. ATP reduction per pmol monoHAA followed the pattern of iodoacetic acid (IAA) > bromoacetic acid (BAA) > chloroacetic acid (CAA), which is the pattern of potency observed with many toxicological endpoints. Exogenous supplementation with pyruvate enhanced ATP levels and attenuated monoHAA-induced genomic DNA damage as measured with single cell gel electrophoresis. These data were highly correlated with the SN 2 alkylating potentials of the monoHAAs and with the induction of toxicity. The results from this study strongly support the hypothesis that GAPDH inhibition and the possible subsequent generation of reactive oxygen species is linked with the cytotoxicity, genotoxicity, teratogenicity, and neurotoxicity of these DBPs.

  10. Pyruvate Remediation of Cell Stress and Genotoxicity Induced by Haloacetic Acid Drinking Water Disinfection By-Products

    PubMed Central

    Dad, Azra; Jeong, Clara H.; Pals, Justin A.; Wagner, Elizabeth D.; Plewa, Michael J.

    2014-01-01

    Monohaloacetic acids (monoHAAs) are a major class of drinking water disinfection by-products (DBPs) and are cytotoxic, genotoxic, mutagenic, and teratogenic. We propose a model of toxic action based on monoHAA-mediated inhibition of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a target cytosolic enzyme. This model predicts that GAPDH inhibition by the monoHAAs will lead to a severe reduction of cellular ATP levels and repress the generation of pyruvate. A loss of pyruvate will lead to mitochondrial stress and genomic DNA damage. We found a concentration-dependent reduction of ATP in Chinese hamster ovary cells after monoHAA treatment. ATP reduction per pmol monoHAA followed the pattern of iodoacetic acid (IAA) > bromoacetic acid (BAA) >> chloroacetic acid (CAA), which is the pattern of potency observed with many toxicological endpoints. Exogenous supplementation with pyruvate enhanced ATP levels and attenuated monoHAA-induced genomic DNA damage as measured with single cell gel electrophoresis. These data were highly correlated with the SN2 alkylating potentials of the monoHAAs and with the induction of toxicity. The results from this study strongly support the hypothesis that GAPDH inhibition and the possible subsequent generation of reactive oxygen species is linked with the cytotoxicity, genotoxicity, teratogenicity, and neurotoxicity of these DBPs. PMID:23893730

  11. Occurrence, synthesis, and mammalian cell cytotoxicity and genotoxicity of haloacetamides: an emerging class of nitrogenous drinking water disinfection byproducts.

    PubMed

    Plewa, Michael J; Muellner, Mark G; Richardson, Susan D; Fasano, Francesca; Buettner, Katherine M; Woo, Yin-Tak; McKague, A Bruce; Wagner, Elizabeth D

    2008-02-01

    The haloacetamides, a class of emerging nitrogenous drinking water disinfection byproduct (DBPs), were analyzed for their chronic cytotoxicity and for the induction of genomic DNA damage in Chinese hamster ovary cells. The rank order for cytotoxicity of 13 haloacetamides was DIAcAm > IAcAm > BAcAm > TBAcAm > BIAcAm > DBCAcAm > CIAcAm > BDCAcAm > DBAcAm > BCAcAm > CAcAm > DCAcAm > TCAcAm. The rank order of their genotoxicity was TBAcAm > DIAcAm approximately equal to IAcAm > BAcAm > DBCAcAm > BIAcAm > BDCAcAm > CIAcAm > BCAcAm > DBAcAm > CAcAm > TCAcAm. DCAcAm was not genotoxic. Cytotoxicity and genotoxicity were primarily determined by the leaving tendency of the halogens and followed the order I > Br > > Cl. With the exception of brominated trihaloacetamides, most of the toxicity rank order was consistent with structure-activity relationship expectations. For di- and trihaloacetamides, the presence of at least one good leaving halogen group (I or Br but not Cl) appears to be critical for significant toxic activity. Log P was not a factor for monohaloacetamides but may play a role in the genotoxicity of trihaloacetamides and possible activation of dihaloacetamides by intracellular GSH and -SH compounds.

  12. [Testing the efficacy of disinfectants during drinking water treatment. A new experimental set-up at the German EPA (Umweltbundesamt - UBA)].

    PubMed

    Grützmacher, G; Bartel, H; Althoff, H W; Clemen, S

    2007-03-01

    A set-up for experiments in the flow-through mode was constructed in order to test the efficacy of substances used for disinfecting water during drinking water treatment. A flow-through mode - in contrast to experiments under stationary conditions (so-called batch experiments) - was chosen, because this experimental design allows experiments to be carried out under constant conditions for an extended time (up to one week) and because efficacy testing is possible repeatedly, simultaneously and under exactly the same conditions for short (about 0.5 min) and also longer (about 47 min) contact times. With this experimental design the effect of biofilms along the inner pipe surfaces can be included in the observations. The construction of the experimental set-up is based on experience with laboratory flow-through systems that were installed by the UBA's drinking water department (formerly Institute for Water-, Soil- and Air Hygiene (WaBoLu) Institute) for testing disinfection with chlorine. In the first step, a test pipe for the simulation of a water works situation was installed. Water of different qualities can be mixed in large volumes beforehand so that the experimental procedure can be run with constant water quality for a minimum of one week. The kinetics of the disinfection reaction can be observed by extracting samples from eight sampling ports situated along the test pipe. In order to assign exact residence times to each of the sampling ports, tracer experiments were performed prior to testing disinfectant efficacy. This paper gives the technical details of the experimental set-up and presents the results of the tracer experiments to provide an introduction with respect to its potential.

  13. [Formation Mechanism of the Disinfection By-product 1, 1-Dichloroacetone in Drinking Water].

    PubMed

    Ding, Chun-sheng; Meng, Zhuang; Xu, Yang-yang; Miao, Jia

    2015-05-01

    A novel method using methyl tertiary butyl ether (MTBE) as extractant and 1,2-dibromopropane as internal standard for the determination of the disinfection by-producs 1,1-dichloroacetone (DCAce) by gas chromatography mass spectrometry (GC-MS) was described. The formation process of DCAce and its influencing factors were discussed with L-leucine as the precursor during the chloramination process. The results indicated that the DCAce production increased with the increase of chloramine dosage when the chloramine addition was in the range of 5-30 mg · L(-1). The DCAce amount produced under alkaline condition was higher than those produced under the neutral and acidic conditions, and the DCAce amount reduced with the increase of pH value. Temperature was another important factor that affected the DCAce formation from methylamine especially in the range of 15-35°C , and the higher the temperature, the more the DCAce produced. The formation process of DCAce from L-leucine by chloramine consisted of a series of complicated reactions, including substitution, oxidation, bond breaking, amino diazotization, reduction and so on, and eventually DCAce was formed.

  14. Drinking Water Disinfection By-Product Rules and Climate Change Effects - A Glimpse of Current and Future Trends

    EPA Science Inventory

    "Drinking water quality at the consumer's tap is the center piece of U.S. drinking water regulations to protect people's health. Recently promulgated Stage II DBP rules are an example, which requires a system approach in a multi-barrier strategy for compliance and risk managemen...

  15. STRAIN COMPARISON IN PREGNANT RATS OF ENDOCRINE RESPONSE TO BROMODICHLOROMETHANE: A DRINKING WATER DISINFECTION BY-PRODUCT

    EPA Science Inventory

    Bromodichloromethane (BDCM), a trihalomethane, is a by-product of the chlorination of drinking water. In an epidemiological study, consumption of drinking water with high levels of BDCM was associated with an increased risk of spontaneous abortion in pregnant women (Waller et al....

  16. [Formation process of nitrogenous disinfection byproduct trichloronitromethane in drinking water and its influencing factors].

    PubMed

    Ding, Chun-Sheng; Zou, Bang-Wen; Miao, Jia; Fu, Yang-Ping; Shen, Jia-Chen

    2013-08-01

    A novel method is described in this paper, which uses methyl tertiary butyl ether (MTBE) as extractant and 1,2-dibromopropane as internal standard for the determination of nitrogenous disinfection byproduct trichloronitromethane (TCNM) by gas chromatography mass spectrometry (GC-MS). The formation process of TCNM and its influencing factors were evaluated with methylamine as the precursor during chlorination. The results indicated that the TCNM amount produced under alkaline condition was higher than those produced under the neutral and acidic conditions, and the TCNM amount increased with the increase of pH value. It was found that the TCNM amount increased with the increase of chlorine addition when the chlorine dosage was in the range of 2-8 mmol x L(-1). However, the TCNM amount was reduced when the chlorine dosage was enhanced from 8 mmol x L(-1) to 12 mmol x L(-1), under which conditions the concentration of free chlorine was higher and methylamine was turned into nitriles and aldehydes through other reactions. It was also found that the TCNM amount increased with the increase of methylamine addition when the methylamine dosage was in the range of 0.5-4 mmol x L(-1). Temperature was another important factor that affected the TCNM formation from methylamine especially in the range of 10-30 degrees C and the higher the temperature, the more the TCNM amount produced. The formation process of TCNM from methylamine by chlorination was in accordance with the mechanism of an electrophilic reaction, in which HClO and ClO(-) could be used as the electrophilic reagents to attack methylamine and then to form TCNM.

  17. Drinking Water

    EPA Science Inventory

    This encyclopedic entry deals with various aspects of microbiology as it relates to drinking water treatment. The use of microbial indicators for assessing fecal contamination is discussed as well as current national drinking water regulations (U.S. EPA) and guidelines proposed ...

  18. WATER, DRINKING

    EPA Science Inventory

    The primary object of the microbiology of drinking water is to prevent waterborne disease. A drinking-water system can minimize waterborne disease by employing proper treatment and cntrol practices, and by monitoring the effectiveness of these practices. Here, these issues are ad...

  19. Epidermal hyperplasia in mouse skin following treatment with alternative drinking water disinfectants

    SciTech Connect

    Robinson, M.; Bull, R.J.; Schamer, M.; Long, R.E.

    1986-11-01

    Female SENCAR mice were treated with aqueous solutions of hypochlorous acid (HOCl), sodium hypochlorite (NaOCl), chlorine dioxide (ClO/sub 2/), and monochloramine (NH/sub 2/Cl) by whole body exposure (except head) for a 10-min period for 4 days in the first experiment and for 1 day (except NH/sub 2/Cl) in the second experiment. Animals were sacrificed the day following the last treatment (experiment 1) or on day 1, 2, 3, 4, 5, 8, 10, and 12 following treatment (experiment 2), and skin thickness was measured by light microscopy. Concentrations of disinfectants were 1, 10, 100, 300, and 1000 mg/L, for experiment 1 and 1000 mg/L for experiment 2. Thickness of the interfollicular epidermis (IFE) for control animals was 15.4 +/- 1.5 ..mu..m. After 4 days of treatment at 1000 mg/L, HOCl and ClO/sub 2/ increased thickness to 30 +/- 7.0 and 40.2 +/- 11.8, and NaOCl increased thickness to 25.2 +/- 6.1 ..mu.. m. The response to HOCl was found to be dose-related. The time-course study following a single treatment of 1000 mg/L HOCl, showed a progression of IFE thickening of from 18.3 +/- 1.4 at 1 day to 30.8 +/- 8.0 at 8 days, decreasing to 19.1 +/- 6.2 ..mu..m at 12 days. ClO/sub 2/ and NaOCl when tested in this manner did not produce increased thickness of IFE with time, but rather gave a persistent level of increase that remained for the 12 days. NH/sub 2/Cl reduced skin thickness to 13.6 +/- 6.1 ..mu..m. Examination of sections of skin treated with HOCl and ClO/sub 2/ indicated an increase in cell numbers. HOCl and ClO/sub 2/ are therefore capable of inducting hyperplastic responses in the mouse skin. The basis for the decrease in skin thickness resulting from NH/sub 2/Cl treatment remains to be established.

  20. Solar Drinking Water Disinfection (SODIS) to Reduce Childhood Diarrhoea in Rural Bolivia: A Cluster-Randomized, Controlled Trial

    PubMed Central

    Mäusezahl, Daniel; Christen, Andri; Pacheco, Gonzalo Duran; Tellez, Fidel Alvarez; Iriarte, Mercedes; Zapata, Maria E.; Cevallos, Myriam; Hattendorf, Jan; Cattaneo, Monica Daigl; Arnold, Benjamin; Smith, Thomas A.; Colford, John M.

    2009-01-01

    Background Solar drinking water disinfection (SODIS) is a low-cost, point-of-use water purification method that has been disseminated globally. Laboratory studies suggest that SODIS is highly efficacious in inactivating waterborne pathogens. Previous field studies provided limited evidence for its effectiveness in reducing diarrhoea. Methods and Findings We conducted a cluster-randomized controlled trial in 22 rural communities in Bolivia to evaluate the effect of SODIS in reducing diarrhoea among children under the age of 5 y. A local nongovernmental organisation conducted a standardised interactive SODIS-promotion campaign in 11 communities targeting households, communities, and primary schools. Mothers completed a daily child health diary for 1 y. Within the intervention arm 225 households (376 children) were trained to expose water-filled polyethyleneteraphtalate bottles to sunlight. Eleven communities (200 households, 349 children) served as a control. We recorded 166,971 person-days of observation during the trial representing 79.9% and 78.9% of the total possible person-days of child observation in intervention and control arms, respectively. Mean compliance with SODIS was 32.1%. The reported incidence rate of gastrointestinal illness in children in the intervention arm was 3.6 compared to 4.3 episodes/year at risk in the control arm. The relative rate of diarrhoea adjusted for intracluster correlation was 0.81 (95% confidence interval 0.59–1.12). The median length of diarrhoea was 3 d in both groups. Conclusions Despite an extensive SODIS promotion campaign we found only moderate compliance with the intervention and no strong evidence for a substantive reduction in diarrhoea among children. These results suggest that there is a need for better evidence of how the well-established laboratory efficacy of this home-based water treatment method translates into field effectiveness under various cultural settings and intervention intensities. Further global

  1. Solar disinfection of drinking water in the prevention of dysentery in South African children aged under 5 years: the role of participant motivation.

    PubMed

    Du Preez, Martella; Mcguigan, Kevin G; Conroy, Ronan M

    2010-11-15

    Solar disinfection (SODIS) effectively improves the microbial quality of drinking water for preventing diarrhea; however, the effect of participant motivation has not been studied. This 1-year randomized controlled trial investigated the effect of SODIS of drinking water and motivation on the incidence of dysentery and nondysentery diarrhea among children of age 6 months to 5 years living in periurban communities in South Africa.We compared 383 children in 297 households using SODIS with 335 children in 267 households with no intervention. At baseline 62.4% of the study households had stored water which met World Health Organization guidelines for zero thermotolerant coliforms per 100 mL. Dysentery was recorded using a pictorial diary. Incidence of dysentery was significantly associated with higher motivation, defined as 75% or better completion of diarrhea data. Incidence rates were lower in those drinking solar disinfected water (incidence rate ratio 0.64, 95% CI 0.39 - 1.0, P = 0.071) but not statistically significant. Compared with the control, participants with higher motivation achieved a significant reduction in dysentery (incidence rate ratio 0.36, 95% CI 0.16 - 0.81, P = 0.014). However, there was no significant reduction in risk at lower levels of motivation. Solar disinfection was not significantly associated with nondysentery diarrhea risk overall (P = 0.419). A statistically significant reduction in dysentery was achieved only in households with higher motivation, showing that motivation is a significant determinant for measurable health gains. Failure of three-quarters of participants to achieve a significant reduction in dysentery suggests that research into effective implementation is required.

  2. Controlling Disinfection Residual Losses in Drinking Water Distribution Systems: Results from Experimental Studies

    EPA Science Inventory

    It is generally accepted that water quality can deteriorate in a distribution system through reactions in the bulk phase and/or at the pipe wall. These reactions may be physical, chemical and/or microbiological in nature. Perhaps one of the most serious aspects of water quality...

  3. Controlling Disinfection Residual Losses in Drinking Water Distribution Systems: Results from Experimental Studies

    EPA Science Inventory

    It has become generally accepted that water quality can deteriorate in a distribution system through reactions in the bulk phase and/or at the pipe wall. These reactions may be physical, chemical and/or microbiological in nature. Perhaps one of the most serious aspects of water...

  4. Disinfection of model indicator organisms in a drinking water pilot plant by using PEROXONE

    SciTech Connect

    Wolfe, R.L.; Stewart, M.H.; Liang, S.; McGuire, M.J. )

    1989-09-01

    PEROXONE is an advanced oxidation process generated by combining ozone and hydrogen peroxide. This process stimulates the production of hydroxyl radicals, which have been shown to be superior to ozone for the destruction of some organic contaminants. In this study, pilot-scale experiments were conducted to evaluate the microbicidal effectiveness of PEROXONE and ozone against three model indicator groups. Escherichia coli and MS2 coliphage were seeded into the influent to the preozonation contactors of a pilot plant simulating conventional water treatment and were exposed to four ozone dosages, four hydrogen peroxide/ozone weight ratios, and four contact times in two source waters--Colorado River water and state project water--of different quality. The removal of heterotrophic plate count bacteria was also monitored. Results of the study indicated that the microbicidal activity of PEROXONE was greatly affected by the applied ozone dose, H2O2/O3 ratio, contact time, source water quality, and type of microorganism tested. At contact times of 5 min or less, ozone alone was a more potent bactericide than PEROXONE at all H2O2/O3 ratios tested. However, this decrease in the bactericidal potency of PEROXONE was dramatic only as the H2O2/O3 ratio was increased from 0.5 to 0.8. The fact that the bactericidal activity of PEROXONE generally decreased with increasing H2O2/O3 ratios was thought to be related to the lower ozone residuals produced. The viricidal activity of PEROXONE and ozone was comparable at all of the H2O2/O3 ratios. Heterotrophic plate count bacteria were the most resistant group of organisms. Greater inactivation of E. coli and MS2 was observed in Colorado River water than in state project water and appeared to result from differences in the turbidity and alkalinity of the two waters. Regardless of source water, greater than 4.5 log10 of E.

  5. Effect of ultraviolet disinfection of drinking water on the viability of Cryptosporidium parvum oocysts.

    PubMed

    Lorenzo-Lorenzo, M J; Ares-Mazas, M E; Villacorta-Martinez de Maturana, I; Duran-Oreiro, D

    1993-02-01

    Demineralized water was enriched with a known number of Cryptosporidium parvum oocysts obtained from fresh calf feces, which were purified and exposed to ultraviolet (UV) light (15,000 mW/sec) for different lengths of time. Coccidium-free litters of CD-1 neonatal mice then were inoculated intragastrically with the treated water. Seven days postinoculation mice were killed and C. parvum infection prevalence and intensity determined. In mice inoculated with C. parvum-enriched water that had been exposed to UV light for at least 150 min, no infection occurred.

  6. NANOFILTRATION FOR REMOVAL OF DRINKING WATER DISINFECTION BY-PRODUCT PRCURSORS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV) program evaluates the performance of innovative air, water, pollution prevention and monitoring technologies that have the potential to improve human health and the environment. This techno...

  7. ANALYTICAL METHODS FOR WATER DISINFECTION BY-PRODUCTS IN FOODS AND BEVERAGES

    EPA Science Inventory

    The determination of exposure to drinking water disinfection byproducts (DBPs) requires an understanding of how drinking waters come into contact with the human through multiple pathways. The most significant pathway is the ingestion of drinking water. However, ingestion can oc...

  8. COMPONENT-BASED AND WHOLE-MIXTURE TECHNIQUES FOR ADDRESSING THE TOXICITY OF DRINKING-WATER DISINFECTION BY-PRODUCT MIXTURES

    EPA Science Inventory

    Chemical disinfection of water is of direct public health benefit as it results in decreased waterborne illness. The chemicals used to disinfect water react with naturally occurring organic matter, bromide and iodide in the source water, resulting in the formation of disinfection...

  9. Relationship Between Redox Potential, Disinfectant, and pH in Drinking Water

    EPA Science Inventory

    This work will examine the effects of pH and oxidant type (chlorine [Cl2], oxygen [O2], hydrogen peroxide [H2O2], monochloramine [MCA], and potassium permanganate [KMnO4]) and concentration (mg/L) on the redox potential of buffered test water. Also, the effects of incrementing ir...

  10. Temporal variability in urinary levels of drinking water disinfection byproducts dichloroacetic acid and trichloroacetic acid among men

    SciTech Connect

    Wang, Yi-Xin; Zeng, Qiang; Wang, Le; Huang, Yue-Hui; Lu, Zhi-Wei; Wang, Peng; He, Meng-Jie; Huang, Xin; Lu, Wen-Qing

    2014-11-15

    Urinary haloacetic acids (HAAs), such as dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), have been suggested as potential biomarkers of exposure to drinking water disinfection byproducts (DBPs). However, variable exposure to and the short elimination half-lives of these biomarkers can result in considerable variability in urinary measurements, leading to exposure misclassification. Here we examined the variability of DCAA and TCAA levels in the urine among eleven men who provided urine samples on 8 days over 3 months. The urinary concentrations of DCAA and TCAA were measured by gas chromatography coupled with electron capture detection. We calculated the intraclass correlation coefficients (ICCs) to characterize the within-person and between-person variances and computed the sensitivity and specificity to assess how well single or multiple urine collections accurately determined personal 3-month average DCAA and TCAA levels. The within-person variance was much higher than the between-person variance for all three sample types (spot, first morning, and 24-h urine samples) for DCAA (ICC=0.08–0.37) and TCAA (ICC=0.09–0.23), regardless of the sampling interval. A single-spot urinary sample predicted high (top 33%) 3-month average DCAA and TCAA levels with high specificity (0.79 and 0.78, respectively) but relatively low sensitivity (0.47 and 0.50, respectively). Collecting two or three urine samples from each participant improved the classification. The poor reproducibility of the measured urinary DCAA and TCAA concentrations indicate that a single measurement may not accurately reflect individual long-term exposure. Collection of multiple urine samples from one person is an option for reducing exposure classification errors in studies exploring the effects of DBP exposure on reproductive health. - Highlights: • We evaluated the variability of DCAA and TCAA levels in the urine among men. • Urinary DCAA and TCAA levels varied greatly over a 3-month

  11. N-nitrosamine formation by monochloramine, free chlorine, and peracetic acid disinfection with presence of amine precursors in drinking water system.

    PubMed

    West, Danielle M; Wu, Qihua; Donovan, Ariel; Shi, Honglan; Ma, Yinfa; Jiang, Hua; Wang, Jianmin

    2016-06-01

    In this study, the formation of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine, N-nitrosomethylamine, N-nitrosodi-n-propylamine, N-nitrosodi-n-butylamine, N-Nitrosopiperidine, N-Nitrosopyrrolidine, N-Nitrosomorpholine, were systematically evaluated with respect to seven N-nitrosamine precursors (dimethylamine, trimethylamine, 3-(dimethylaminomethyl)indole, 4-dimethylaminoantipyrine, ethylmethylamine, diethylamine, dipropylamine) and three disinfectants (monochloramine, free chlorine, peracetic acid) under variable dosages, exposure times, and pH in a drinking water system. Without the presence of the seven selected N-nitrosamine precursors N-nitrosamine formation was not observed under any tested condition except very low levels of N-Nitrosopyrrolidine under some conditions. With selected N-nitrosamine precursors present N-nitrosamines formed at different levels under different conditions. The highest N-nitrosamine formation was NDMA with a maximum concentration of 1180 ng/L by monochloramine disinfection with precursors present; much lower levels of N-nitrosamines were formed by free chlorine disinfection; and no detectable level of N-nitrosamines were observed by peracetic acid disinfection except low level of N-Nitrosodi-n-propylamine under some conditions. NDMA formation was not affected by pH while four other N-nitrosamine formations were slightly affected by sample pH tested between 7 and 9, with formation decreasing with increasing pH. Monochloramine exposure time study displayed fast formation of N-nitrosamines, largely formed in four hours of exposure and maximized after seven days. This was a systematic study on the N-nitrosamine formation with the seven major N-nitrosamine precursors presence and absence under different conditions, including peracetic acid disinfection which has not been studied elsewhere.

  12. N-nitrosamine formation by monochloramine, free chlorine, and peracetic acid disinfection with presence of amine precursors in drinking water system.

    PubMed

    West, Danielle M; Wu, Qihua; Donovan, Ariel; Shi, Honglan; Ma, Yinfa; Jiang, Hua; Wang, Jianmin

    2016-06-01

    In this study, the formation of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine, N-nitrosomethylamine, N-nitrosodi-n-propylamine, N-nitrosodi-n-butylamine, N-Nitrosopiperidine, N-Nitrosopyrrolidine, N-Nitrosomorpholine, were systematically evaluated with respect to seven N-nitrosamine precursors (dimethylamine, trimethylamine, 3-(dimethylaminomethyl)indole, 4-dimethylaminoantipyrine, ethylmethylamine, diethylamine, dipropylamine) and three disinfectants (monochloramine, free chlorine, peracetic acid) under variable dosages, exposure times, and pH in a drinking water system. Without the presence of the seven selected N-nitrosamine precursors N-nitrosamine formation was not observed under any tested condition except very low levels of N-Nitrosopyrrolidine under some conditions. With selected N-nitrosamine precursors present N-nitrosamines formed at different levels under different conditions. The highest N-nitrosamine formation was NDMA with a maximum concentration of 1180 ng/L by monochloramine disinfection with precursors present; much lower levels of N-nitrosamines were formed by free chlorine disinfection; and no detectable level of N-nitrosamines were observed by peracetic acid disinfection except low level of N-Nitrosodi-n-propylamine under some conditions. NDMA formation was not affected by pH while four other N-nitrosamine formations were slightly affected by sample pH tested between 7 and 9, with formation decreasing with increasing pH. Monochloramine exposure time study displayed fast formation of N-nitrosamines, largely formed in four hours of exposure and maximized after seven days. This was a systematic study on the N-nitrosamine formation with the seven major N-nitrosamine precursors presence and absence under different conditions, including peracetic acid disinfection which has not been studied elsewhere. PMID:27037659

  13. Effect of the radiation intensity, water turbidity and exposure time on the survival of Cryptosporidium during simulated solar disinfection of drinking water.

    PubMed

    Gómez-Couso, Hipólito; Fontán-Sainz, María; McGuigan, Kevin G; Ares-Mazás, Elvira

    2009-10-01

    The solar disinfection (SODIS) technique is a highly effective process that makes use of solar energy to inactivate pathogenic microorganisms in drinking water in developing countries. The pathogenic protozoan parasite Cryptosporidium parvum is often found in surface waters and is associated with waterborne outbreaks of cryptosporidiosis. In the present study, a complete multi-factorial mathematical model was used to investigate the combined effects of the intensity of solar radiation (200, 600 and 900W/m(2) in the 320nm to 10microm range), water turbidity (5, 100 and 300 NTU) and exposure time (4, 8 and 12h) on the viability and infectivity of C. parvum oocysts during simulated SODIS procedures at a constant temperature of 30 degrees C. All three factors had significant effects (p<0.05) on C. parvum survival, as did the interactions of water turbidity with radiation intensity and radiation intensity with exposure time. However, the parameter with the greatest effect was the intensity of radiation; levels > or =600W/m(2) and times of exposure between 8 and 12h were required to reduce the oocyst infectivity in water samples with different degrees of turbidity.

  14. Changes in dissolved organic matter during the treatment processes of a drinking water plant in Sweden and formation of previously unknown disinfection byproducts.

    PubMed

    Gonsior, Michael; Schmitt-Kopplin, Philippe; Stavklint, Helena; Richardson, Susan D; Hertkorn, Norbert; Bastviken, David

    2014-11-01

    The changes in dissolved organic matter (DOM) throughout the treatment processes in a drinking water treatment plant in Sweden and the formation of disinfection byproducts (DBPs) were evaluated by using ultra-high-resolution mass spectrometry (resolution of ∼500,000 at m/z 400) and nuclear magnetic resonance (NMR). Mass spectrometric results revealed that flocculation induced substantial changes in the DOM and caused quantitative removal of DOM constituents that usually are associated with DBP formation. While half of the chromophoric DOM (CDOM) was removed by flocculation, ∼4-5 mg L(-1) total organic carbon remained in the finished water. A conservative approach revealed the formation of ∼800 mass spectrometry ions with unambiguous molecular formula assignments that contained at least one halogen atom. These molecules likely represented new DBPs, which could not be prevented by the flocculation process. The most abundant m/z peaks, associated with formed DBPs, could be assigned to C5HO3Cl3, C5HO3Cl2Br, and C5HO3ClBr2 using isotope simulation patterns. Other halogen-containing formulas suggested the presence of halogenated polyphenolic and aromatic acid-type structures, which was supported by possible structures that matched the lower molecular mass range (maximum of 10 carbon atoms) of these DBPs. 1H NMR before and after disinfection revealed an ∼2% change in the overall 1H NMR signals supporting a significant change in the DOM caused by disinfection. This study underlines the fact that a large and increasing number of people are exposed to a very diverse pool of organohalogens through water, by both drinking and uptake through the skin upon contact. Nontarget analytical approaches are indispensable for revealing the magnitude of this exposure and to test alternative ways to reduce it.

  15. A stepped wedge, cluster-randomized trial of a household UV-disinfection and safe storage drinking water intervention in rural Baja California Sur, Mexico.

    PubMed

    Gruber, Joshua S; Reygadas, Fermin; Arnold, Benjamin F; Ray, Isha; Nelson, Kara; Colford, John M

    2013-08-01

    In collaboration with a local non-profit organization, this study evaluated the expansion of a program that promoted and installed Mesita Azul, an ultraviolet-disinfection system designed to treat household drinking water in rural Mexico. We conducted a 15-month, cluster-randomized stepped wedge trial by randomizing the order in which 24 communities (444 households) received the intervention. We measured primary outcomes (water contamination and diarrhea) during seven household visits. The intervention increased the percentage of households with access to treated and safely stored drinking water (23-62%), and reduced the percentage of households with Escherichia coli contaminated drinking water (risk difference (RD): -19% [95% CI: -27%, -14%]). No significant reduction in diarrhea was observed (RD: -0.1% [95% CI: -1.1%, 0.9%]). We conclude that household water quality improvements measured in this study justify future promotion of the Mesita Azul, and that future studies to measure its health impact would be valuable if conducted in populations with higher diarrhea prevalence. PMID:23732255

  16. A Stepped Wedge, Cluster-Randomized Trial of a Household UV-Disinfection and Safe Storage Drinking Water Intervention in Rural Baja California Sur, Mexico

    PubMed Central

    Gruber, Joshua S.; Reygadas, Fermin; Arnold, Benjamin F.; Ray, Isha; Nelson, Kara; Colford, John M.

    2013-01-01

    In collaboration with a local non-profit organization, this study evaluated the expansion of a program that promoted and installed Mesita Azul, an ultraviolet-disinfection system designed to treat household drinking water in rural Mexico. We conducted a 15-month, cluster-randomized stepped wedge trial by randomizing the order in which 24 communities (444 households) received the intervention. We measured primary outcomes (water contamination and diarrhea) during seven household visits. The intervention increased the percentage of households with access to treated and safely stored drinking water (23–62%), and reduced the percentage of households with Escherichia coli contaminated drinking water (risk difference (RD): −19% [95% CI: −27%, −14%]). No significant reduction in diarrhea was observed (RD: −0.1% [95% CI: −1.1%, 0.9%]). We conclude that household water quality improvements measured in this study justify future promotion of the Mesita Azul, and that future studies to measure its health impact would be valuable if conducted in populations with higher diarrhea prevalence. PMID:23732255

  17. A stepped wedge, cluster-randomized trial of a household UV-disinfection and safe storage drinking water intervention in rural Baja California Sur, Mexico.

    PubMed

    Gruber, Joshua S; Reygadas, Fermin; Arnold, Benjamin F; Ray, Isha; Nelson, Kara; Colford, John M

    2013-08-01

    In collaboration with a local non-profit organization, this study evaluated the expansion of a program that promoted and installed Mesita Azul, an ultraviolet-disinfection system designed to treat household drinking water in rural Mexico. We conducted a 15-month, cluster-randomized stepped wedge trial by randomizing the order in which 24 communities (444 households) received the intervention. We measured primary outcomes (water contamination and diarrhea) during seven household visits. The intervention increased the percentage of households with access to treated and safely stored drinking water (23-62%), and reduced the percentage of households with Escherichia coli contaminated drinking water (risk difference (RD): -19% [95% CI: -27%, -14%]). No significant reduction in diarrhea was observed (RD: -0.1% [95% CI: -1.1%, 0.9%]). We conclude that household water quality improvements measured in this study justify future promotion of the Mesita Azul, and that future studies to measure its health impact would be valuable if conducted in populations with higher diarrhea prevalence.

  18. Viruses in non-disinfected groundwater used for municipal drinking water and the incidence of acute gastrointestinal illness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human viruses from fecal wastes have been known to contaminate the groundwater supplies of municipal drinking water systems. The relationship of these sporadic virus detections in groundwater to human health risk is unknown. We quantified virus concentrations by real-time qPCR in the tap water of ...

  19. Viruses in non-disinfected drinking water from municipal wells are related to community rates of acute gastrointestinal illness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Groundwater supplies for drinking water are frequently contaminated with low-levels of human enteric virus genomes, yet evidence for waterborne disease transmission is lacking. We related qPCR-measured enteric viruses in the tap water of 14 non-chlorinating communities in the U.S. to acute gastroint...

  20. Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: a review and roadmap for research.

    PubMed

    Richardson, Susan D; Plewa, Michael J; Wagner, Elizabeth D; Schoeny, Rita; Demarini, David M

    2007-01-01

    Disinfection by-products (DBPs) are formed when disinfectants (chlorine, ozone, chlorine dioxide, or chloramines) react with naturally occurring organic matter, anthropogenic contaminants, bromide, and iodide during the production of drinking water. Here we review 30 years of research on the occurrence, genotoxicity, and carcinogenicity of 85 DBPs, 11 of which are currently regulated by the U.S., and 74 of which are considered emerging DBPs due to their moderate occurrence levels and/or toxicological properties. These 74 include halonitromethanes, iodo-acids and other unregulated halo-acids, iodo-trihalomethanes (THMs), and other unregulated halomethanes, halofuranones (MX [3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone] and brominated MX DBPs), haloamides, haloacetonitriles, tribromopyrrole, aldehydes, and N-nitrosodimethylamine (NDMA) and other nitrosamines. Alternative disinfection practices result in drinking water from which extracted organic material is less mutagenic than extracts of chlorinated water. However, the levels of many emerging DBPs are increased by alternative disinfectants (primarily ozone or chloramines) compared to chlorination, and many emerging DBPs are more genotoxic than some of the regulated DBPs. Our analysis identified three categories of DBPs of particular interest. Category 1 contains eight DBPs with some or all of the toxicologic characteristics of human carcinogens: four regulated (bromodichloromethane, dichloroacetic acid, dibromoacetic acid, and bromate) and four unregulated DBPs (formaldehyde, acetaldehyde, MX, and NDMA). Categories 2 and 3 contain 43 emerging DBPs that are present at moderate levels (sub- to low-mug/L): category 2 contains 29 of these that are genotoxic (including chloral hydrate and chloroacetaldehyde, which are also a rodent carcinogens); category 3 contains the remaining 14 for which little or no toxicological data are available. In general, the brominated DBPs are both more genotoxic and carcinogenic

  1. Comparison of different solar reactors for household disinfection of drinking water in developing countries: evaluation of their efficacy in relation to the waterborne enteropathogen Cryptosporidium parvum.

    PubMed

    Gómez-Couso, H; Fontán-Sainz, M; Navntoft, C; Fernández-Ibáñez, P; Ares-Mazás, E

    2012-11-01

    Solar water disinfection (SODIS) is a type of treatment that can significantly improve the microbiological quality of drinking water at household level and therefore prevent waterborne diseases in developing countries. Cryptosporidium parvum is an obligate protozoan parasite responsible for the diarrhoeal disease cryptosporidiosis in humans and animals. Recently, this parasite has been selected by the WHO as a reference pathogen for protozoan parasites in the evaluation of household water treatment options. In this study, the field efficacy of different static solar reactors [1.5 l transparent plastic polyethylene terephthalate (PET) bottles as well as 2.5 l borosilicate glass and 25 l methacrylate reactors fitted with compound parabolic concentrators (CPC)] for solar disinfection of turbid waters experimentally contaminated with C. parvum oocysts was compared. Potential oocyst viability was determined by inclusion/exclusion of the fluorogenic vital dye propidium iodide. The results demonstrate that static solar reactors fitted with CPCs are an excellent alternative to the conventional SODIS method with PET bottles. These reactors improved the efficacy of the SODIS method by enabling larger volumes of water to be treated and, in some cases, the C. parvum oocysts were rendered totally unviable, minimising the negative effects of turbidity. PMID:23032082

  2. Comparison of different solar reactors for household disinfection of drinking water in developing countries: evaluation of their efficacy in relation to the waterborne enteropathogen Cryptosporidium parvum.

    PubMed

    Gómez-Couso, H; Fontán-Sainz, M; Navntoft, C; Fernández-Ibáñez, P; Ares-Mazás, E

    2012-11-01

    Solar water disinfection (SODIS) is a type of treatment that can significantly improve the microbiological quality of drinking water at household level and therefore prevent waterborne diseases in developing countries. Cryptosporidium parvum is an obligate protozoan parasite responsible for the diarrhoeal disease cryptosporidiosis in humans and animals. Recently, this parasite has been selected by the WHO as a reference pathogen for protozoan parasites in the evaluation of household water treatment options. In this study, the field efficacy of different static solar reactors [1.5 l transparent plastic polyethylene terephthalate (PET) bottles as well as 2.5 l borosilicate glass and 25 l methacrylate reactors fitted with compound parabolic concentrators (CPC)] for solar disinfection of turbid waters experimentally contaminated with C. parvum oocysts was compared. Potential oocyst viability was determined by inclusion/exclusion of the fluorogenic vital dye propidium iodide. The results demonstrate that static solar reactors fitted with CPCs are an excellent alternative to the conventional SODIS method with PET bottles. These reactors improved the efficacy of the SODIS method by enabling larger volumes of water to be treated and, in some cases, the C. parvum oocysts were rendered totally unviable, minimising the negative effects of turbidity.

  3. DISINFECTION

    EPA Science Inventory

    The primary goal of the disinfection process in drinking water treatment is the inactivation of microbial pathogens. These pathogens comprise a diverse group of organisms which serve as the etiological agents of waterborne disease. Included in this group are bacterial, viral and ...

  4. Concentration, chlorination, and chemical analysis of drinking water for disinfection byproduct mixtures health effects research: U.S. EPA's Four Lab Study.

    PubMed

    Pressman, Jonathan G; Richardson, Susan D; Speth, Thomas F; Miltner, Richard J; Narotsky, Michael G; Hunter, E Sidney; Rice, Glenn E; Teuschler, Linda K; McDonald, Anthony; Parvez, Shahid; Krasner, Stuart W; Weinberg, Howard S; McKague, A Bruce; Parrett, Christopher J; Bodin, Nathalie; Chinn, Russell; Lee, Chih-Fen T; Simmons, Jane Ellen

    2010-10-01

    The U.S. Environmental Protection Agency's "Four Lab Study" involved participation of researchers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from the water industry and academia. The study evaluated toxicological effects of complex disinfection byproduct (DBP) mixtures, with an emphasis on reproductive and developmental effects that have been associated with DBP exposures in some human epidemiologic studies. This paper describes a new procedure for producing chlorinated drinking water concentrate for animal toxicology experiments, comprehensive identification of >100 DBPs, and quantification of 75 priority and regulated DBPs. In the research reported herein, complex mixtures of DBPs were produced by concentrating a natural source water with reverse osmosis membranes, followed by addition of bromide and treatment with chlorine. By concentrating natural organic matter in the source water first and disinfecting with chlorine afterward, DBPs (including volatiles and semivolatiles) were formed and maintained in a water matrix suitable for animal studies. DBP levels in the chlorinated concentrate compared well to those from EPA's Information Collection Rule (ICR) and a nationwide study of priority unregulated DBPs when normalized by total organic carbon (TOC). DBPs were relatively stable over the course of the animal studies (125 days) with multiple chlorination events (every 5-14 days), and a significant portion of total organic halogen was accounted for through a comprehensive identification approach. DBPs quantified included regulated DBPs, priority unregulated DBPs, and additional DBPs targeted by the ICR. Many DBPs are reported for the first time, including previously undetected and unreported haloacids and haloamides. The new concentration procedure not only produced a concentrated drinking water suitable for animal experiments, but also provided a greater TOC concentration factor (136

  5. Concentration, chlorination, and chemical analysis of drinking water for disinfection byproduct mixtures health effects research: U.S. EPA's Four Lab Study.

    PubMed

    Pressman, Jonathan G; Richardson, Susan D; Speth, Thomas F; Miltner, Richard J; Narotsky, Michael G; Hunter, E Sidney; Rice, Glenn E; Teuschler, Linda K; McDonald, Anthony; Parvez, Shahid; Krasner, Stuart W; Weinberg, Howard S; McKague, A Bruce; Parrett, Christopher J; Bodin, Nathalie; Chinn, Russell; Lee, Chih-Fen T; Simmons, Jane Ellen

    2010-10-01

    The U.S. Environmental Protection Agency's "Four Lab Study" involved participation of researchers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from the water industry and academia. The study evaluated toxicological effects of complex disinfection byproduct (DBP) mixtures, with an emphasis on reproductive and developmental effects that have been associated with DBP exposures in some human epidemiologic studies. This paper describes a new procedure for producing chlorinated drinking water concentrate for animal toxicology experiments, comprehensive identification of >100 DBPs, and quantification of 75 priority and regulated DBPs. In the research reported herein, complex mixtures of DBPs were produced by concentrating a natural source water with reverse osmosis membranes, followed by addition of bromide and treatment with chlorine. By concentrating natural organic matter in the source water first and disinfecting with chlorine afterward, DBPs (including volatiles and semivolatiles) were formed and maintained in a water matrix suitable for animal studies. DBP levels in the chlorinated concentrate compared well to those from EPA's Information Collection Rule (ICR) and a nationwide study of priority unregulated DBPs when normalized by total organic carbon (TOC). DBPs were relatively stable over the course of the animal studies (125 days) with multiple chlorination events (every 5-14 days), and a significant portion of total organic halogen was accounted for through a comprehensive identification approach. DBPs quantified included regulated DBPs, priority unregulated DBPs, and additional DBPs targeted by the ICR. Many DBPs are reported for the first time, including previously undetected and unreported haloacids and haloamides. The new concentration procedure not only produced a concentrated drinking water suitable for animal experiments, but also provided a greater TOC concentration factor (136

  6. Analysis of preneoplastic and neoplastic renal lesions in Tsc2 mutant Long-Evans (Eker) rats following exposure to a mixture of drinking water disinfection by-products.

    PubMed

    McDorman, Kevin S; Hooth, Michelle J; Starr, Thomas B; Wolf, Douglas C

    2003-05-01

    Disinfection of surface water for human consumption results in the generation of a complex mixture of chemicals in potable water. Cancer risk assessment methodology assumes additivity of carcinogenic effects in the regulation of mixtures. A rodent model of hereditary renal cancer was used to investigate the carcinogenic response to a mixture of drinking water disinfection by-products (DBPs). Rats carrying a mutation in the Tsc2 tumor suppressor gene (Eker rats) readily develop renal preneoplastic and neoplastic lesions, and are highly susceptible to the effects of renal carcinogens. Male and female Eker rats were exposed via drinking water to individual or a mixture of DBPs for 4 or 10 months. Potassium bromate, 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), chloroform, and bromodichloromethane were administered at low concentrations of 0.02, 0.005, 0.4 and 0.07 g/l, respectively, and high concentrations of 0.4, 0.07, 1.8 and 0.7 g/l, respectively. Low and high dose mixture solutions were comprised of all four chemicals at either low concentrations or high concentrations, respectively, Following necropsy, each kidney was examined microscopically for preneoplastic lesions (atypical tubules and hyperplasias) and tumors. While some of the mixture responses observed in male rats did fall within the range expected for an additive response, especially at the high dose, predominantly antagonistic effects on renal lesions were observed in response to the low dose mixture in male rats and the high dose mixture in female rats. These data suggest that current default risk assessments assuming additivity may overstate the cancer risk associated with exposure to mixtures of DBPs at low concentrations. PMID:12679048

  7. Photovoltaic powered ultraviolet and visible light-emitting diodes for sustainable point-of-use disinfection of drinking waters.

    PubMed

    Lui, Gough Yumu; Roser, David; Corkish, Richard; Ashbolt, Nicholas; Jagals, Paul; Stuetz, Richard

    2014-09-15

    For many decades, populations in rural and remote developing regions will be unable to access centralised piped potable water supplies, and indeed, decentralised options may be more sustainable. Accordingly, improved household point-of-use (POU) disinfection technologies are urgently needed. Compared to alternatives, ultraviolet (UV) light disinfection is very attractive because of its efficacy against all pathogen groups and minimal operational consumables. Though mercury arc lamp technology is very efficient, it requires frequent lamp replacement, involves a toxic heavy metal, and their quartz envelopes and sleeves are expensive, fragile and require regular cleaning. An emerging alternative is semiconductor-based units where UV light emitting diodes (UV-LEDs) are powered by photovoltaics (PV). Our review charts the development of these two technologies, their current status, and challenges to their integration and POU application. It explores the themes of UV-C-LEDs, non-UV-C LED technology (e.g. UV-A, visible light, Advanced Oxidation), PV power supplies, PV/LED integration and POU suitability. While UV-C LED technology should mature in the next 10 years, research is also needed to address other unresolved barriers to in situ application as well as emerging research opportunities especially UV-A, photocatalyst/photosensitiser use and pulsed emission options. PMID:24946032

  8. Photovoltaic powered ultraviolet and visible light-emitting diodes for sustainable point-of-use disinfection of drinking waters.

    PubMed

    Lui, Gough Yumu; Roser, David; Corkish, Richard; Ashbolt, Nicholas; Jagals, Paul; Stuetz, Richard

    2014-09-15

    For many decades, populations in rural and remote developing regions will be unable to access centralised piped potable water supplies, and indeed, decentralised options may be more sustainable. Accordingly, improved household point-of-use (POU) disinfection technologies are urgently needed. Compared to alternatives, ultraviolet (UV) light disinfection is very attractive because of its efficacy against all pathogen groups and minimal operational consumables. Though mercury arc lamp technology is very efficient, it requires frequent lamp replacement, involves a toxic heavy metal, and their quartz envelopes and sleeves are expensive, fragile and require regular cleaning. An emerging alternative is semiconductor-based units where UV light emitting diodes (UV-LEDs) are powered by photovoltaics (PV). Our review charts the development of these two technologies, their current status, and challenges to their integration and POU application. It explores the themes of UV-C-LEDs, non-UV-C LED technology (e.g. UV-A, visible light, Advanced Oxidation), PV power supplies, PV/LED integration and POU suitability. While UV-C LED technology should mature in the next 10 years, research is also needed to address other unresolved barriers to in situ application as well as emerging research opportunities especially UV-A, photocatalyst/photosensitiser use and pulsed emission options.

  9. INDUCTION OF TRANSTITIONAL CELL HYPERPLASIA IN THE URINARY BLADDER AND ABERRANT CRYPT FOCI IN THE COLON OF RATS TREATED WITH INDIVIDUAL AND A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    ABSTRACT

    Cancer of the urinary bladder and colon are significant human health concerns. Epidemiological studies have suggested a correlation between these cancers and the chronic consumption of drinking water containing disinfection by-products (DBPs). The present study...

  10. Use of mechanism-based structure-activity relationships analysis in carcinogenic potential ranking for drinking water disinfection by-products.

    PubMed Central

    Woo, Yin-Tak; Lai, David; McLain, Jennifer L; Manibusan, Mary Ko; Dellarco, Vicki

    2002-01-01

    Disinfection by-products (DBPs) are formed when disinfectants such as chlorine, chloramine, and ozone react with organic and inorganic matter in water. The observations that some DBPs such as trihalomethanes (THMs), di-/trichloroacetic acids, and 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) are carcinogenic in animal studies have raised public concern over the possible adverse health effects of DBPs. To date, several hundred DBPs have been identified. To prioritize research efforts, an in-depth, mechanism-based structure-activity relationship analysis, supplemented by extensive literature search for genotoxicity and other data, was conducted for ranking the carcinogenic potential of DBPs that met the following criteria: a) detected in actual drinking water samples, b) have insufficient cancer bioassay data for risk assessment, and c) have structural features/alerts or short-term predictive assays indicative of carcinogenic potential. A semiquantitative concern rating scale of low, marginal, low-moderate, moderate, high-moderate, and high was used along with delineation of scientific rationale. Of the 209 DBPs analyzed, 20 were of priority concern with a moderate or high-moderate rating. Of these, four were structural analogs of MX and five were haloalkanes that presumably will be controlled by existing and future THM regulations. The other eleven DBPs, which included halonitriles (6), haloketones (2), haloaldehyde (1), halonitroalkane (1), and dialdehyde (1), are suitable priority candidates for future carcinogenicity testing and/or mechanistic studies. PMID:11834465

  11. Measuring the concentrations of drinking water disinfection by-products using capillary membrane sampling-flow injection analysis.

    PubMed

    Geme, Gija; Brown, Michael A; Simone, Paul; Emmert, Gary L

    2005-10-01

    A capillary membrane sampling-flow injection analysis method is presented for selectively measuring the concentrations of total trihalomethanes (THMs) and total haloacetic acids (HAAs) in drinking water. The method is based on the reaction between nicotinamide and THM or HAA species to yield a fluorescent product. Two configurations are presented, one selective for total THMs and another selective for total HAAs. The construction of a capillary membrane sampler is described, and the results of method detection limit, accuracy and precision studies are reported for each method. Interference, selectivity and linearity studies are reported as well as the effect of temperature and ionic strength changes. Drinking water samples were analyzed by each proposed method and the results were compared to USEPA methods 502.2 and 552.3.

  12. Monochloramine Cometabolism by Nitrosomonas europaea under Drinking Water Conditions

    EPA Science Inventory

    Chloramine use is widespread in United States drinking water systems as a secondary disinfectant. While beneficial from the perspective of controlling disinfectant by-product formation, chloramination may promote the growth of nitrifying bacteria because ammonia is present. At ...

  13. The removal process of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product, in drinking water treatment process and its toxicity on zebrafish.

    PubMed

    Lin, Tao; Zhou, Dongju; Yu, Shilin; Chen, Wei

    2016-09-01

    The removal process of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product (DBP) in conventional drinking water treatment plant (C-DWTP) and advanced DWTP (ADWTP) was studied with newly maximum formation potential (MFP) process. It was demonstrated that the advanced treatment displayed greater removal efficiency towards DCAcAm formation potential (MFP) than the conventional treatment. The hydrophilic natural organic matter and natural organic matter with molecular weight <1 kDa or >10 kDa leaded to more DCAcAm formation, and the aromatic protein was inferred as one part of DCAcAm precursor. DCAcAm was found to cause delayed development and malformation to zebrafish embryos at embryonic growth stage. Compared with heart toxicity, it caused a significant neuron toxicity. It also could cause the acute DNA damage to adult zebrafish, which should be extremely cautioned.

  14. DEVELOPMENT OF A RESEARCH STRATEGY FOR INTEGRATED TECHNOLOGY-BASED TOXICOLOGICAL AND CHEMICAL EVALUATION OF COMPLEX MIXTURES OF DRINKING WATER DISINFECTION BYPRODUCTS

    EPA Science Inventory

    Chemical disinfection of water is a major public health triumph of the 20th century. Dramatic decreases in both morbidity and mortality of waterborne diseases are a direct result of water disinfection. With these important public health benefits comes low-level, chronic exposure ...

  15. Four groups of new aromatic halogenated disinfection byproducts: effect of bromide concentration on their formation and speciation in chlorinated drinking water.

    PubMed

    Pan, Yang; Zhang, Xiangru

    2013-02-01

    Bromide is naturally present in source waters worldwide. Chlorination of drinking water can generate a variety of chlorinated and brominated disinfection byproducts (DBPs). Although substantial efforts have been made to examine the effect of bromide concentration on the formation and speciation of halogenated DBPs, almost all previous studies have focused on trihalomethanes and haloacetic acids. Given that about 50% of total organic halogen formed in chlorination remains unknown, it is still unclear how bromide concentration affects the formation and speciation of the new/unknown halogenated DBPs. In this study, chlorinated drinking water samples with different bromide concentrations were prepared, and a novel approach-precursor ion scan using ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry-was adopted for the detection and identification of polar halogenated DBPs in these water samples. With this approach, 11 new putative aromatic halogenated DBPs were identified, and they were classified into four groups: dihalo-4-hydroxybenzaldehydes, dihalo-4-hydroxybenzoic acids, dihalo-salicylic acids, and trihalo-phenols. A mechanism for the formation of the four groups of new aromatic halogenated DBPs was proposed. It was found that increasing the bromide concentration shifted the entire polar halogenated DBPs as well as the four groups of new DBPs from being less brominated to being more brominated; these new aromatic halogenated DBPs might be important intermediate DBPs formed in drinking water chlorination. Moreover, the speciation of the four groups of new DBPs was modeled: the speciation patterns of the four groups of new DBPs well matched those determined from the model equations, and the reactivity differences between HOBr and HOCl in reactions forming the four groups of new DBPs were larger than those in reactions forming trihalomethanes and haloacetic acids.

  16. Toxicology of drinking water disinfection byproducts from nutrients. Rate studies of destruction of polyunsaturated fatty acids in vitro by chlorine-based disinfectants.

    PubMed

    Bercz, J P

    1992-01-01

    As model reactions between unsaturated fats and water disinfectants in the GI tract, relative rates of destruction of seven polyunsaturated fatty acids (L, alpha Ln, gamma Ln, Ara, EPA, DH, and DT) by OCl- and NH2Cl were investigated in vitro. Using millimolar solutions of seven PUFAs combined with various OCl- mole ratios, disappearance of PUFAs was followed by UV spectrophotometry at pH = 9.5 and at 35 degrees C via conjugated hydroperoxydienes at 234 nm. While OCl- rapidly destroyed all PUFAs, NH2Cl was inert. Overall second-order rate constants computed for L at increasing times disclosed that the attack on the cis-CH=CHCH2CH=CH moiety by OCl- does not follow simple second-order kinetics. Using a logit-log transform and second-order polynomial regression analysis of L's disappearance in a stoichiometric ([L] = 1.2 mM; [ClO-] = 2.4 mM) mix, data were analyzed by the time ratio method of Schwemer and Frost. These agreed with a sequential system of at least two irreversible second-order reactions having k1 = 15.6 L.mol-1.s-1 and k2 = 2.6 L.mol-1.s-1. Preliminary GC/MS analysis indicated that the initial product is a mix of chlorohydrin isomers. These undergo second addition of HOCl and/or lose halogens and polymerize. Additional minor products were also C5-C9 mono- and bifunctional carboxylates and mixed acid aldehydes. Studies with mol equiv of Cl- - free 36ClO- allowed estimation of covalent binding of Cl by L at various times, supporting the kinetic findings. For other PUFAs of higher degree unsaturation, the complexity of feasible reactions precluded an analogous approach.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Solar disinfection of drinking water (SODIS): an investigation of the effect of UV-A dose on inactivation efficiency.

    PubMed

    Ubomba-Jaswa, Eunice; Navntoft, Christian; Polo-López, M Inmaculada; Fernandez-Ibáñez, Pilar; McGuigan, Kevin G

    2009-05-01

    The effect of solar UV-A irradiance and solar UV-A dose on the inactivation of Escherichia coli K-12 using solar disinfection (SODIS) was studied. E. coli K-12 was seeded in natural well-water contained in borosilicate glass tubes and exposed to sunlight at different irradiances and doses of solar UV radiation. In addition, E. coli K-12 was also inoculated into poly(ethylene) terephthalate (PET) bottles and in a continuous flow system (10 L min(-1)) to determine the effect of an interrupted and uninterrupted solar dose on inactivation. Results showed that inactivation from approximately 10(6) CFU mL(-1) to below the detection level (4 CFU/mL) for E. coli K-12, is a function of the total uninterrupted dose delivered to the bacteria and that the minimum dose should be >108 kJ m(-2) for the conditions described (spectral range of 0.295-0.385 microm). For complete inactivation to below the limit of detection, this dose needs to be received regardless of the incident solar UV intensity and needs to be delivered in a continuous and uninterrupted manner. This is illustrated by a continuous flow system in which bacteria were not fully inactivated (residual viable concentration approximately 10(2) CFU/mL) even after 5 h of exposure to strong sunlight and a cumulative dose of >108 kJ m(-2). This has serious implications for attempts to scale-up solar disinfection through the use of re-circulatory continuous flow reactors.

  18. Short-term spatial and temporal variability of disinfection by-product occurrence in small drinking water systems.

    PubMed

    Guilherme, Stéphanie; Rodriguez, Manuel J

    2015-06-15

    Disinfection by-products (DBPs) constitute a large family of compounds. Trihalomethanes and haloacetic acids are regulated in various countries, but most DBPs are not. Monitoring DBPs can be delicate, especially for small systems, because various factors influence their formation and speciation. Short-term variations of DBPs can be important and particularly difficult for small systems to handle because they require robust treatment and operation processes. According to our knowledge, for the first time, our study covers the short-term variability of regulated and non-regulated DBP occurrence in small systems in the summer. An intensive sampling program was carried out in six small systems in Canada. Systems in the provinces of Newfoundland and Labrador and Quebec were sampled daily at the water treatment plant and at six different locations along the distribution system. Five DBP families were studied: trihalomethanes, haloacetic acids, haloacetonitriles, halonitromethanes and haloketones. Results show that there were considerable variations in DBP levels from week to week during the month of study and even from day to day within the week. On a daily basis, DBP levels can fluctuate by 22% to 96%. Likewise, the large number of sampling locations served to observe DBP variations along the distribution system. Observations revealed some degradation and decomposition of non-regulated DBPs never before studied in small systems that are associated with the difficulty these systems experience in maintaining adequate levels of residual disinfectant. Finally, this study reveals that the short term temporal variability of DBPs is also influenced by spatial location along the distribution system. In the short term, DBP levels can fluctuate by 23% at the beginning of the system, compared to 40% at the end. Thus, spatial and temporal variations of DBPs in the short term may make it difficult to select representative locations and periods for DBP monitoring purposes in small

  19. Effect of disinfection of drinking water with ozone or chlorine dioxide on survival of Cryptosporidium parvum oocysts.

    PubMed Central

    Peeters, J E; Mazás, E A; Masschelein, W J; Villacorta Martiez de Maturana, I; Debacker, E

    1989-01-01

    Demineralized water was seeded with controlled numbers of oocysts of Cryptosporidium parvum purified from fresh calf feces and subjected to different treatments with ozone or chlorine dioxide. The disinfectants were neutralized by sodium thiosulfate, and neonatal mice were inoculated intragastrically and sacrificed 7 days later for enumeration of oocyst production. Preliminary trials indicated that a minimum infection level of 1,000 oocysts (0.1-ml inoculum) per mouse was necessary to induce 100% infection. Treatment of water containing 10(4) oocysts per ml with 1.11 mg of ozone per liter (concentration at time zero [C0]) for 6 min totally eliminated the infectivity of the oocysts for neonatal mice. A level of 2.27 mg of ozone per liter (C0) was necessary to inactivate water containing 5 x 10(5) oocysts per ml within 8 min. Also, 0.4 mg of chlorine dioxide per liter (C0) significantly reduced infectivity within 15 min of contact, although some oocysts remained viable. PMID:2764564

  20. Effect of Common Drinking Water Disinfectants, Chlorine and Heat, on Free Legionella and Amoebae-Associated Legionella

    PubMed Central

    Cervero-Aragó, Sílvia; Rodríguez-Martínez, Sarah; Puertas-Bennasar, Antoni; Araujo, Rosa M.

    2015-01-01

    Chlorine and thermal treatments are the most commonly used procedures to control and prevent Legionella proliferation in drinking water systems of large buildings. However, cases of legionellosis still occur in facilities with treated water. The purpose of this work was to model the effect of temperature and free chlorine applied in similar exposure conditions as in drinking water systems on five Legionella spp. strains and two amoebal strains of the genera Acanthamoeba. Inactivation models obtained were used to determine the effectiveness of the treatments applied which resulted more effective against Legionella than Acanthamoeba, especially those in cystic stages. Furthermore, to determine the influence of the relationship between L. pneumophila and Acanthamoeba spp. on the treatment effectiveness, inactivation models of the bacteria-associated amoeba were also constructed and compared to the models obtained for the free living bacteria state. The Legionella-amoeba association did not change the inactivation models, but it reduced the effectiveness of the treatments applied. Remarkably, at the lowest free chlorine concentration, 0.5 mg L-1, as well as at the lowest temperatures, 50°C and 55°C, the influence of the Legionella-amoeba associate state was the strongest in reducing the effectiveness of the treatments compared to the free Legionella state. Therefore, the association established between L. pneumophila and amoebae in the water systems indicate an increased health risk in proximal areas of the system (close to the tap) where lower free chlorine concentrations and lower temperatures are commonly observed. PMID:26241039

  1. Effect of Common Drinking Water Disinfectants, Chlorine and Heat, on Free Legionella and Amoebae-Associated Legionella.

    PubMed

    Cervero-Aragó, Sílvia; Rodríguez-Martínez, Sarah; Puertas-Bennasar, Antoni; Araujo, Rosa M

    2015-01-01

    Chlorine and thermal treatments are the most commonly used procedures to control and prevent Legionella proliferation in drinking water systems of large buildings. However, cases of legionellosis still occur in facilities with treated water. The purpose of this work was to model the effect of temperature and free chlorine applied in similar exposure conditions as in drinking water systems on five Legionella spp. strains and two amoebal strains of the genera Acanthamoeba. Inactivation models obtained were used to determine the effectiveness of the treatments applied which resulted more effective against Legionella than Acanthamoeba, especially those in cystic stages. Furthermore, to determine the influence of the relationship between L. pneumophila and Acanthamoeba spp. on the treatment effectiveness, inactivation models of the bacteria-associated amoeba were also constructed and compared to the models obtained for the free living bacteria state. The Legionella-amoeba association did not change the inactivation models, but it reduced the effectiveness of the treatments applied. Remarkably, at the lowest free chlorine concentration, 0.5 mg L-1, as well as at the lowest temperatures, 50°C and 55°C, the influence of the Legionella-amoeba associate state was the strongest in reducing the effectiveness of the treatments compared to the free Legionella state. Therefore, the association established between L. pneumophila and amoebae in the water systems indicate an increased health risk in proximal areas of the system (close to the tap) where lower free chlorine concentrations and lower temperatures are commonly observed.

  2. Effect of Common Drinking Water Disinfectants, Chlorine and Heat, on Free Legionella and Amoebae-Associated Legionella.

    PubMed

    Cervero-Aragó, Sílvia; Rodríguez-Martínez, Sarah; Puertas-Bennasar, Antoni; Araujo, Rosa M

    2015-01-01

    Chlorine and thermal treatments are the most commonly used procedures to control and prevent Legionella proliferation in drinking water systems of large buildings. However, cases of legionellosis still occur in facilities with treated water. The purpose of this work was to model the effect of temperature and free chlorine applied in similar exposure conditions as in drinking water systems on five Legionella spp. strains and two amoebal strains of the genera Acanthamoeba. Inactivation models obtained were used to determine the effectiveness of the treatments applied which resulted more effective against Legionella than Acanthamoeba, especially those in cystic stages. Furthermore, to determine the influence of the relationship between L. pneumophila and Acanthamoeba spp. on the treatment effectiveness, inactivation models of the bacteria-associated amoeba were also constructed and compared to the models obtained for the free living bacteria state. The Legionella-amoeba association did not change the inactivation models, but it reduced the effectiveness of the treatments applied. Remarkably, at the lowest free chlorine concentration, 0.5 mg L-1, as well as at the lowest temperatures, 50°C and 55°C, the influence of the Legionella-amoeba associate state was the strongest in reducing the effectiveness of the treatments compared to the free Legionella state. Therefore, the association established between L. pneumophila and amoebae in the water systems indicate an increased health risk in proximal areas of the system (close to the tap) where lower free chlorine concentrations and lower temperatures are commonly observed. PMID:26241039

  3. Developmental toxicity evaluations of whole mixtures of disinfection by-products using concentrated drinking water in rats: gestational and lactational effects of sulfate and sodium.

    PubMed

    Narotsky, Michael G; Pressman, Jonathan G; Miltner, Richard J; Speth, Thomas F; Teuschler, Linda K; Rice, Glenn E; Richardson, Susan D; Best, Deborah S; McDonald, Anthony; Hunter, E Sidney; Simmons, Jane Ellen

    2012-06-01

    A developmental toxicity bioassay was used in three experiments to evaluate water concentrates for suitability in multigenerational studies. First, chlorinated water was concentrated 135-fold by reverse osmosis; select lost disinfection by-products were spiked back. Concentrate was provided as drinking water to Sprague-Dawley and F344 rats from gestation day 6 to postnatal day 6. Maternal serum levels of luteinizing hormone on gestation day 10 were unaffected by treatment for both strains. Treated dams had increased water consumption, and increased incidences of polyuria, diarrhea, and (in Sprague-Dawley rats) red perinasal staining. Pup weights were reduced. An increased incidence of eye defects was seen in F344 litters. Chemical analysis of the concentrate revealed high sodium (6.6 g/l) and sulfate (10.4 g/l) levels. To confirm that these chemicals caused polyuria and osmotic diarrhea, respectively, Na₂SO₄ (5-20 g/l) or NaCl (16.5 g/l) was provided to rats in drinking water. Water consumption was increased at 5- and 10-g Na₂SO₄/l and with NaCl. Pup weights were reduced at 20-g Na₂SO₄/l. Dose-related incidences and severity of polyuria and diarrhea occurred in Na₂SO₄-treated rats; perinasal staining was seen at 20 g/l. NaCl caused polyuria and perinasal staining, but not diarrhea. Subsequently, water was concentrated ∼120-fold and sulfate levels were reduced by barium hydroxide before chlorination, yielding lower sodium (≤1.5 g/l) and sulfate (≤2.1 g/l) levels. Treatment resulted in increased water consumption, but pup weight and survival were unaffected. There were no treatment-related clinical findings, indicating that mixtures produced by the second method are suitable for multigenerational testing.

  4. Optical monitoring of Disinfection By-product Precursors with Fluorescence Excitation-Emission Mapping (F-EEM): Practical Application Issues for Drinking, Waste and Reuse Water Industry

    NASA Astrophysics Data System (ADS)

    Gilmore, A. M.

    2012-12-01

    Drinking water, wastewater and reuse plants must deal with regulations associated with bacterial contamination and halogen disinfection procedures that can generate harmful disinfection by-products (DBPs) including trihalomethanes (THMs), haloacetic acids (HOAAs) and other compounds. The natural fluorescent chromophoric dissolved organic matter (CDOM) is regulated as the major DBP precursor. This study outlines the advantages and current limitations associated with optical monitoring of water treatment processes using tcontemporary Fluorescence Excitation-Emission Mapping (F-EEM). The F-EEM method coupled with practical peak indexing and multi-variate analyses is potentially superior in terms of cost, speed and sensitivity over conventional total organic carbon (TOC) meters and specific UV-absorbance (SUVA) measurements. Hence there is strong interest in developing revised environmental regulations around the F-EEM technique instruments which can incidentally simultaneously measure the SUVA and DOC parameters. Importantly, the F-EEM technique, compared to the single-point TOC and SUVA signals can resolve CDOM classes distinguishing those that strongly cause DBPs. The F-EEM DBP prediction method can be applied to surface water sources to evaluate DBP potential as a function of the point sources and reservoir depth profiles. It can also be applied in-line to rapidly adjust DOC removal processes including sedimentation-flocculation, microfiltration, reverse-osmosis, and ozonation. Limitations and interferences for F-EEMs are discussed including those common to SUVA and TOC in contrast to the advantages including that F-EEMs are less prone to interferences from inorganic carbon and metal contaminations and require little if any chemical preparation. In conclusion, the F-EEM method is discussed in terms of not only the DBP problem but also as a means of predicting (concurrent to DBP monitoring) organic membrane fouling in water-reuse and desalination plants.

  5. ANALYTICAL METHODS FOR WATER DISINFECTION BYPRODUCTS IN FOODS AND BEVERAGES

    EPA Science Inventory

    The determination of exposure to drinking water disinfection byproducts (DBPs) requires an understanding of how drinking water comes into contact with human through multiple pathways. In order to facilitate the investigation of human exposure to DBPs via foods and beverages, anal...

  6. Influence of Disinfectant Residual on Biofilm Development, Microbial Ecology, and Pathogen Fate and Transport in Drinking Water Infrastructure

    EPA Science Inventory

    This project focuses on providing basic data to bound risk estimates resulting from pathogens associated with pipe biofilms. Researchers will compare biofilm pathogen effects under two different disinfection scenarios (free chlorine or chloramines) for a conventionally treated s...

  7. The occurrence of disinfection by-products in municipal drinking water in China's Pearl River Delta and a multipathway cancer risk assessment.

    PubMed

    Gan, Wenhui; Guo, Wanhong; Mo, Jianmin; He, Yisen; Liu, Yongjian; Liu, Wei; Liang, Yongmei; Yang, Xin

    2013-03-01

    Disinfection byproducts were measured in the finished drinking water from ten water treatment plants in three Chinese cities - Guangzhou, Foshan and Zhuhai. A total of 155 water samples were collected in 2011 and 2012. The median (range) of trihalomethane (THM) and haloacetic acid (HAA) levels were 17.7 (0.7-62.7) μg/L and 8.6 (0.3-81.3) μg/L, respectively. Chloroform, dichloroacetic acid and trichloroacetic acid were the dominant species observed in Guangzhou and Foshan water, while brominated THMs predominated in water from Zhuhai. Haloacetonitriles, haloketones, chloral hydrate and trichloronitromethane were usually detected at levels ranging from unquantifiable (<0.2μg/L) to 12.2μg/L (choral hydrate). THMs and HAAs showed clear seasonal variations with the total concentrations higher in winter than in summer. Correlations among DBP levels varied, with the strongest linear correlation observed between chloroform and chloral hydrate levels (R(2)=0.77). The risk of cancer from ingestion, inhalation and dermal contact exposure to THMs was estimated. CHCl2Br contributed the highest percentage of the cancer risk from ingestion pathway and CHCl3 contributed the highest of cancer risk from inhalation pathway.

  8. Monitoring of chlorination disinfection by-products and their associated health risks in drinking water of Pakistan.

    PubMed

    Abbas, Sidra; Hashmi, Imran; Rehman, Muhammad Saif Ur; Qazi, Ishtiaq A; Awan, Mohammad A; Nasir, Habib

    2015-03-01

    This study reports the baseline data of chlorination disinfection by-products such as trihalomethanes (THMs) and their associated health risks in the water distribution network of Islamabad and Rawalpindi, Pakistan. THM monitoring was carried out at 30 different sampling sites across the twin cities for 6 months. The average concentration of total trihalomethanes (TTHMs) and chloroform ranged between 575 and 595 μg/L which exceeded the permissible US (80 μg/L) and EU (100 μg/L) limits. Chloroform was one of the major contributors to the TTHMs concentration (>85%). The occurrence of THMs was found in the following order: chloroform, bromodichloromethane > dibromochloromethane > bromoform. Lifetime cancer risk assessment of THMs for both males and females was carried out using prediction models via different exposure routes (ingestion, inhalation, and dermal). Total lifetime cancer risk assessment for different exposure routes (ingestion, inhalation, and skin) was carried out. The highest cancer risk expected from THMs seems to be from the inhalation route followed by ingestion and dermal contacts. The average lifetime cancer risk for males and females was found to be 0.51 × 10⁻³ and 1.22 × 10⁻³, respectively. The expected number of cancer risks per year could reach two to three cases for each city. PMID:25719485

  9. Reducing Volatile Disinfection By-Products in Treated Drinking Water Using Aeration Technologies (WaterRF Report 4441)

    EPA Science Inventory

    The primary objective of this project was to evaluate cost-effective aeration technology solutions to address TTHM compliance at a water treatment plant clearwell. The project team worked closely with EPA Region 6 and the EPA Office of Research and Development (ORD) to identify a...

  10. Strategies for the removal of halides from drinking water sources, and their applicability in disinfection by-product minimisation: a critical review.

    PubMed

    Watson, K; Farré, M J; Knight, N

    2012-11-15

    The presence of bromide (Br(-)) and iodide (I(-)) in source waters leads to the formation of brominated and iodinated disinfection by-products (DBPs), which are often more toxic than their chlorinated analogues. The increasing scarcity of water resources in Australia is leading to use of impaired and alternative water supplies with high bromide and iodide levels, which may result in the production of more brominated and iodinated DBPs. This review aims to provide a summary of research into bromide and iodide removal from drinking water sources. Bromide and iodide removal techniques have been broadly classified into three categories, namely; membrane, electrochemical and adsorptive techniques. Reverse osmosis, nanofiltration and electrodialysis membrane techniques are reviewed. The electrochemical techniques discussed are electrolysis, capacitive deionization and membrane capacitive deionization. Studies on bromide and iodide removal using adsorptive techniques including; layered double hydroxides, impregnated activated carbons, carbon aerogels, ion exchange resins, aluminium coagulation and soils are also assessed. Halide removal techniques have been compared, and areas for future research have been identified.

  11. A preliminary Ames fluctuation assay assessment of the genotoxicity of drinking water that has been solar disinfected in polyethylene terephthalate (PET) bottles.

    PubMed

    Ubomba-Jaswa, Eunice; Fernández-Ibáñez, Pilar; McGuigan, Kevin G

    2010-12-01

    Though microbially safe, concerns have been raised about the genotoxic/mutagenic quality of solar-disinfected drinking water, which might be compromised as a result of photodegradation of polyethylene terephthalate (PET) bottles used as SODIS reactors. This study assessed genotoxic risk associated with the possible release of genotoxic compounds into water from PET bottles during SODIS, using the Ames fluctuation test. Negative genotoxicity results were obtained for water samples that had been in PET bottles and exposed to normal SODIS conditions (strong natural sunlight) over 6 months. Under SODIS conditions, bottles were exposed to 6 h of sunlight, followed by overnight room temperature storage. They were then emptied and refilled the following day and exposed to sunlight again. Genotoxicity was detected after 2 months in water stored in PET bottles and exposed continuously (without refilling) to sunlight for a period ranging from 1 to 6 months. However, similar genotoxicity results were also observed for the dark control (without refill) samples at the same time-point and in no other samples after that time; therefore it is unlikely that this genotoxicity event is related to solar exposure.

  12. Water disinfection: microbes versus molecules - an introduction of issues

    SciTech Connect

    Fowle, J.R. III, Kopfler, F.C.

    1986-11-01

    If the chemicals used to rid drinking water of disease-causing microbes are themselves potentially harmful, is drinking water safe. What trade-offs are acceptable with respect to microbial versus chemical water quality. This conference deals with current thinking about these topics. The subjects discussed reflect the evolution of thinking, both scientifically and socially, about how best to supply the public with safe, pure potable water. The goal of this paper is to introduce the issues associated with disinfectants and disinfectant by-products in water. This will be done by presenting a historical overview of the use of chemical disinfectants to purify drinking water and the subsequent awareness of potential health concerns. Historically, the major health issue associated with water has been the demonstrated role that water has played in spreading infectious disease. Waterborne infectious agents remain in the environment, and new ones emerge through evolution of humans and microorganisms and because of changing exposure patterns.

  13. CHANGES IN THE CECAL MICROBIAL METABOLISM OF RATS INDUCED BY INDIVIDUAL AND A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    ABSTRACT

    Water treatment results in the production of numerous halogenated disinfection byproducts (DBPs), and has been associated with human colorectal cancer. Because the intestinal microbiota can bioactivate xenobiotics, several studies have been done to examine the eff...

  14. TREATMENT OF LONG-EVANS RATS WITH A DEFINED MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS IMPACTS INTESTINAL MICROBIAL METABOLISM.

    EPA Science Inventory

    Water treatment results in the production of numerous halogenated disinfection by-products (DBPs), and has been associated with human colorectal cancer. Because the intestinal microbiota can bioactivate promutagens and procarcinogens, several studies have been done to examine the...

  15. High compliance randomized controlled field trial of solar disinfection of drinking water and its impact on childhood diarrhea in rural Cambodia.

    PubMed

    McGuigan, Kevin G; Samaiyar, Priyajit; du Preez, Martella; Conroy, Ronán M

    2011-09-15

    Recent solar disinfection (SODIS) studies in Bolivia and South Africa have reported compliance rates below 35% resulting in no overall statistically significant benefit associated with disease rates. In this study, we report the results of a 1 year randomized controlled trial investigating the effect of SODIS of drinking water on the incidence of dysentery and nondysentery diarrhea among children of age 6 months to 5 years living in rural communities in Cambodia. We compared 426 children in 375 households using SODIS with 502 children in 407 households with no intervention. Study compliance was greater than 90% with only 5% of children having less than 10 months of follow-up and 2.3% having less than 6 months. Adjusted for water source type, children in the SODIS group had a reduced incidence of dysentery, with an incidence rate ratio (IRR) of 0.50 (95% CI 0.27-0.93, p = 0.029). SODIS also had a protective effect against nondysentery diarrhea, with an IRR of 0.37 (95% CI 0.29-0.48, p < 0.001). This study suggests strongly that SODIS is an effective and culturally acceptable point-of-use water treatment method in the culture of rural Cambodia and may be of benefit among similar communities in neighboring South East Asian countries.

  16. THE OCCURRENCE OF DISINFECTION BY-PRODUCTS OF HEALTH CONCERN IN DRINKING WATER: RESULTS OF A NATIONWIDE DBP OCCURRENCE STUDY

    EPA Science Inventory

    The motivation for this Nationwide Disinfection By-product (DBP) Occurrence Study was two-fold: First, more than 500 DBPs have been reported in the literature, yet there is almost no quantitative occurrence information for most. As a result, there is significant uncertainty ove...

  17. Trophic state, natural organic matter content, and disinfection by-product formation potential of six drinking water reservoirs in the Pearl River Delta, China

    NASA Astrophysics Data System (ADS)

    Hong, Hua Chang; Wong, Ming Hung; Mazumder, Asit; Liang, Yan

    2008-09-01

    SummaryThis study examined spatial and seasonal variation of nutrients, algal biomass, and natural organic matter (NOM) in six subtropical drinking water reservoirs in the Pearl River Delta region, China, during the period from 2004 to 2006. We also tested the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) as disinfection by-products (DBPs) via chlorination of the water samples from these reservoirs. This study showed that these reservoirs were mesotrophic with the average chlorophyll a (Chl a) levels ranging from 2.31 to 7.79 μg l -1. The average dissolved organic carbon (DOC) in the six reservoirs was 2.70 mg l -1, and the degree of aromaticity of NOM indicated by UV 254 (absorbance at 254 nm) was 0.048 cm -1. Total phosphorous (TP) was significantly correlated with chlorophyll a, as well as DOC and UV 254. It suggested that the major component of NOM, with a specific UV 254 value (SUV 254) of 1.78 l mg -1 m -1, was algal-derived organic matter. Existing models from other studies could be used to predict THM yield from NOM level in the present study, but the relationship between HAAs and NOM suggested that aromatic portion of the NOM in the investigated reservoirs had a greater potential to produce HAAs.

  18. Microbial ecology of drinking water distribution systems.

    PubMed

    Berry, David; Xi, Chuanwu; Raskin, Lutgarde

    2006-06-01

    The supply of clean drinking water is a major, and relatively recent, public health milestone. Control of microbial growth in drinking water distribution systems, often achieved through the addition of disinfectants, is essential to limiting waterborne illness, particularly in immunocompromised subpopulations. Recent inquiries into the microbial ecology of distribution systems have found that pathogen resistance to chlorination is affected by microbial community diversity and interspecies relationships. Research indicates that multispecies biofilms are generally more resistant to disinfection than single-species biofilms. Other recent findings are the increased survival of the bacterial pathogen Legionella pneumophila when present inside its protozoan host Hartmannella vermiformis and the depletion of chloramine disinfectant residuals by nitrifying bacteria, leading to increased overall microbial growth. Interactions such as these are unaccounted for in current disinfection models. An understanding of the microbial ecology of distribution systems is necessary to design innovative and effective control strategies that will ensure safe and high-quality drinking water. PMID:16701992

  19. Comparative cytotoxic and genotoxic potential of 13 drinking water disinfection by-products using a microplate-based cytotoxicity assay and a developed SOS/umu assay.

    PubMed

    Zhang, Shao-Hui; Miao, Dong-Yue; Tan, Li; Liu, Ai-Lin; Lu, Wen-Qing

    2016-01-01

    The implications of disinfection by-products (DBPs) present in drinking water are of public health concern because of their potential mutagenic, carcinogenic and other toxic effects on humans. In this study, we selected 13 main DBPs found in drinking water to quantitatively analyse their cytotoxicity and genotoxicity using a microplate-based cytotoxicity assay and a developed SOS/umu assay in Salmonella typhimurium TA1535/pSK1002. With the developed SOS/umu test, eight DBPs: 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-fura3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone (MX), dibromoacetonitrile (DBN), iodoacetic acid (IA), bromochloroacetonitrile (BCN), bromoacetic acid (BA), trichloroacetonitrile (TCN), dibromoacetic acid (DBA) and dichloroacetic acid (DCA) were significantly genotoxic to S. typhimurium. Three DBPs: chloroacetic acid (CA), trichloroacetic acid (TCA) and dichloroacetonitrile (DCN) were weakly genotoxic, whereas the remaining DBPs: chloroacetonitrile (CN) and chloral hydrate (CH) were negative. The rank order in decreasing genotoxicity was as follows: MX > DBN > IA > BCN > BA > TCN > DBA > DCA > CA, TCA, DCN > CN, CH. MX was approximately 370 000 times more genotoxic than DCA. In the microplate-based cytotoxicity assay, cytotoxic potencies of the 13 DBPs were compared and ranked in decreasing order as follows: MX > IA > DBN > BCN > BA > TCN > DCN > CA > DCA > DBA > CN > TCA > CH. MX was approximately 19 200 times more cytotoxic than CH. A statistically significant correlation was found between cytotoxicity and genotoxicity of the 13 DBPs in S. typhimurium. Results suggest that microplate-based cytotoxicity assay and the developed SOS/umu assay are feasible tools for analysing the cytotoxicity and genotoxicity of DBPs, particularly for comparing their toxic intensities quantitatively.

  20. Comparative cytotoxic and genotoxic potential of 13 drinking water disinfection by-products using a microplate-based cytotoxicity assay and a developed SOS/umu assay.

    PubMed

    Zhang, Shao-Hui; Miao, Dong-Yue; Tan, Li; Liu, Ai-Lin; Lu, Wen-Qing

    2016-01-01

    The implications of disinfection by-products (DBPs) present in drinking water are of public health concern because of their potential mutagenic, carcinogenic and other toxic effects on humans. In this study, we selected 13 main DBPs found in drinking water to quantitatively analyse their cytotoxicity and genotoxicity using a microplate-based cytotoxicity assay and a developed SOS/umu assay in Salmonella typhimurium TA1535/pSK1002. With the developed SOS/umu test, eight DBPs: 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-fura3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone (MX), dibromoacetonitrile (DBN), iodoacetic acid (IA), bromochloroacetonitrile (BCN), bromoacetic acid (BA), trichloroacetonitrile (TCN), dibromoacetic acid (DBA) and dichloroacetic acid (DCA) were significantly genotoxic to S. typhimurium. Three DBPs: chloroacetic acid (CA), trichloroacetic acid (TCA) and dichloroacetonitrile (DCN) were weakly genotoxic, whereas the remaining DBPs: chloroacetonitrile (CN) and chloral hydrate (CH) were negative. The rank order in decreasing genotoxicity was as follows: MX > DBN > IA > BCN > BA > TCN > DBA > DCA > CA, TCA, DCN > CN, CH. MX was approximately 370 000 times more genotoxic than DCA. In the microplate-based cytotoxicity assay, cytotoxic potencies of the 13 DBPs were compared and ranked in decreasing order as follows: MX > IA > DBN > BCN > BA > TCN > DCN > CA > DCA > DBA > CN > TCA > CH. MX was approximately 19 200 times more cytotoxic than CH. A statistically significant correlation was found between cytotoxicity and genotoxicity of the 13 DBPs in S. typhimurium. Results suggest that microplate-based cytotoxicity assay and the developed SOS/umu assay are feasible tools for analysing the cytotoxicity and genotoxicity of DBPs, particularly for comparing their toxic intensities quantitatively. PMID:26188195

  1. U.S. DRINKING WATER REGULATIONS: TREATMENT TECHNOLOGIES AND COST.

    EPA Science Inventory

    The Safe Drinking Water Act and its Amendments have imposed a large number of new regulations on the U.S. drinking water industry. A major set of regulations currently under consideration will control disinfectants and disinfection by-products. Included in the development of th...

  2. Ultraviolet disinfection of potable water

    SciTech Connect

    Wolfe, R.L. )

    1990-06-01

    Because of upcoming surface and groundwater regulations regarding the control of microbiological and chemical contaminants, there is a need to evaluate the feasibility and effectiveness of ultraviolet (UV) radiation for primary disinfection of potable water supplies. Data is presented on microbicidal wavelengths of UV and distribution of energy output for low and medium-pressure arc lamps. Both systems were found to perform equally well for inactivating microorganisms, but each had distinct advantages in different applications. Approximate dosages for 90% inactivation of selected microorganisms by UV is presented in a table. Cost analysis for disinfection is presented in two tables as well as the advantages and disadvantages of UV disinfection. 38 refs.

  3. Review of water disinfection techniques

    NASA Technical Reports Server (NTRS)

    Colombo, Gerald V.; Sauer, Richard L.

    1987-01-01

    Throughout the history of manned space flight the supply of potable water to the astronauts has presented unique problems. Of particular concern has been the microbiological quality of the potable water. This has required the development of both preflight water system servicing procedures to disinfect the systems and inflight disinfectant addition and monitoring devices to ensure continuing microbiological control. The disinfectants successfully used to date have been aqueous chlorine or iodine. Because of special system limitations the use of iodine has been the most successful for inflight use and promises to be the agent most likely to be used in the future. Future spacecraft potable, hygiene, and experiment water systems will utilize recycled water. This will present special problems for water quality control. NASA is currently conducting research and development to solve these problems.

  4. Randomized intervention study of solar disinfection of drinking water in the prevention of dysentery in Kenyan children aged under 5 years.

    PubMed

    du Preez, Martella; Conroy, Ronan M; Ligondo, Sophie; Hennessy, James; Elmore-Meegan, Michael; Soita, Allan; McGuigan, Kevin G

    2011-11-01

    We report the results of a randomized controlled intervention study (September 2007 to March 2009) investigating the effect of solar disinfection (SODIS) of drinking water on the incidence of dysentery, nondysentery diarrhea, and anthropometric measurements of height and weight among children of age 6 months to 5 years living in peri-urban and rural communities in Nakuru, Kenya. We compared 555 children in 404 households using SODIS with 534 children in 361 households with no intervention. Dysentery was recorded using a pictorial diary. Incidence rate ratios (IRR) for both number of days and episodes of dysentery and nondysentery diarrhea were significantly (P < 0.001) reduced by use of solar disinfection: dysentery days IRR = 0.56 (95% CI 0.40 to 0.79); dysentery episodes IRR = 0.55 (95% CI 0.42 to 0.73); nondysentery days IRR = 0.70 (95% CI 0.59 to 0.84); nondysentery episodes IRR = 0.73 (95% CI 0.63 to 0.84). Anthropometry measurements of weight and height showed median height-for-age was significantly increased in those on SODIS, corresponding to an average of 0.8 cm over a 1-year period over the group as a whole (95% CI 0.7 to 1.6 cm, P = 0.031). Median weight-for-age was higher in those on SODIS, corresponding to a 0.23 kg difference in weight over the same period; however, the confidence interval spanned zero and the effect fell short of statistical significance (95% CI -0.02 to 0.47 kg, P = 0.068). SODIS and control households did not differ in the microbial quality of their untreated household water over the follow-up period (P = 0.119), but E. coli concentrations in SODIS bottles were significantly lower than those in storage containers over all follow-up visits (P < 0.001). This is the first trial to show evidence of the effect of SODIS on childhood anthropometry, compared with children in the control group and should alleviate concerns expressed by some commentators that the lower rates of dysentery associated with SODIS are the product of biased

  5. Climate change influence on drinking water quality

    NASA Astrophysics Data System (ADS)

    Kovacs, Melinda Haydee; Ristoiu, Dumitru; Voica, Cezara; Moldovan, Zaharie

    2013-11-01

    Although it are quite well known the possible effects of climate changes on surface waters availability and their hydrological risks, their consequences on drinking water quality is not well defined yet. Disinfection agents (as Cl2, O3, etc.) or multiple combinations of them for water treatment and disinfection purposes are applied by water treatment plants at worldwide level. Unfortunately, besides the benefits of these processes were also highlighted some undesirable effects such as formation of several disinfection by-products (DBPs) after reaction of disinfection agent with natural organic matter (NOM) from water body. DBPs formation in drinking water, suspected to posses adverse health effects to humans are strongly regulated in our days. Thus, throughout this study kinetics experiments both the main physicochemical factors that influencing the quality of drinking waters were evaluated as well how they act through possible warming or the consequences of extreme events. Increasing water temperatures with 1 - 5 °C above its normal value has showed that NOMs are presented in higher amount which led to the need for greater amount of disinfectant agent (5 - 15 %). Increasing the amount of disinfecting agent resulted in the formation of DBPs in significantly higher concentrations (between 5 - 30 %).

  6. ANALYSIS OF PRENEOPLASTIC AND NEOPLASTIC RENAL LESIONS IN TSC2 MUTANT LONG-EVANS (EKER) RATS FOLLOWING EXPOSURE TO A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Abstract

    Disinfection of surface water for human consumption results in the generation of a complex mixture of chemicals in potable water. Cancer risk assessment methodology assumes additivity of carcinogenic effects in the regulation of mixtures. A rodent model of ...

  7. Evaluation of the efficiency of the photo Fenton disinfection of natural drinking water source during the rainy season in the Sahelian region.

    PubMed

    Ndounla, J; Pulgarin, C

    2014-09-15

    The photo-disinfection of water from two different wells (W1, pH: 4.6-5.1 ± 0.02) and (W2 pH: 5.6-5.7 ± 0.02) was carried out during the rainy season at Ouagadougou-Burkina Faso, West Africa. The weather variation during the rainy season significantly affects the photo-disinfection processes (solar disinfection and photo-Fenton). The dilution of the water by rainwater highly affected the chemical composition of the wells' water used in this study; very low iron contents Compared to the ones recorded during the dry season were recorded in all water samples. Both photo-disinfection processes were used to treat 25 L of water in a compound parabolic collector (CPC). None of them have shown the total inactivation of both wild enteric bacteria strains (total coliforms/E. coli and Salmonella spp.) involved in the treatment. However, the total coliforms/E. coli strains were totally inactivated during the exposure under most of the photo-Fenton treatment. Also, the remaining strains, especially those of Salmonella spp. were achieved during the subsequent 24h of dark storage under the action of the Fenton process. Under uniquely solar radiation, total inactivation was recorded only in the total coliforms/E. coli strains. The impact of the available irradiance on the efficiency of the photo-Fenton disinfection of natural water was highlighted during the exposure under high intermittent solar radiation. The impact of the HCO3(-) concentration of both wells' water on the evolution of the pH during the photo-disinfection was recorded. Drastic decrease was noticed after the initial fast increase in presence of low HCO3(-) concentration while a steady state was observed after the increase in presence of higher concentration. The redox activities of the nitrogen components of the water during both photo-disinfection processes have led to increased concentration of nitrite in all the cases and variations were noticed in that of nitrate and ammonia.

  8. Recycled Water Poses Disinfectant Problem

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the possible health hazards resulting from released nucleic acid of inactivated viruses, chlorinated nonliving organic molecules, and overestimated reliability of waste treatment standards. Suggests the recycle system use a dual disinfectant such as chlorine and ozone in water treatment. (CC)

  9. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters - slides

    EPA Science Inventory

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired powerplants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. W...

  10. Estimating Potential Increased Bladder Cancer Risk Due to Increased Bromide Concentrations in Sources of Disinfected Drinking Waters

    EPA Science Inventory

    Public water systems are increasingly facing higher bromide levels in their source waters from anthropogenic contamination through coal-fired power plants, conventional oil and gas extraction, and hydraulic fracturing. Climate change is likely to exacerbate this in coming years. ...

  11. Development of a research strategy for integrated technology-based toxicological and chemical evaluation of complex mixtures of drinking water disinfection byproducts.

    PubMed Central

    Simmons, Jane Ellen; Richardson, Susan D; Speth, Thomas F; Miltner, Richard J; Rice, Glenn; Schenck, Kathleen M; Hunter, E Sidney; Teuschler, Linda K

    2002-01-01

    Chemical disinfection of water is a major public health triumph of the 20th century. Dramatic decreases in both morbidity and mortality of waterborne diseases are a direct result of water disinfection. With these important public health benefits comes low-level, chronic exposure to a very large number of disinfection byproducts (DBPs), chemicals formed through reaction of the chemical disinfectant with naturally occurring inorganic and organic material in the source water. This article provides an overview of joint research planning by scientists residing within the various organizations of the U.S. Environmental Protection Agency Office of Research and Development. The purpose is to address concerns related to potential health effects from exposure to DBPs that cannot be addressed directly from toxicological studies of individual DBPs or simple DBP mixtures. Two factors motivate the need for such an investigation of complex mixtures of DBPs: a) a significant amount of the material that makes up the total organic halide and total organic carbon portions of the DBPs has not been identified; and b) epidemiologic data, although not conclusive, are suggestive of potential developmental, reproductive, or carcinogenic health effects in humans exposed to DBPs. The plan is being developed and the experiments necessary to determine the feasibility of its implementation are being conducted by scientists from the National Health and Environmental Effects Research Laboratory, the National Risk Management Research Laboratory, the National Exposure Research Laboratory, and the National Center for Environmental Assessment. PMID:12634133

  12. Development of a research strategy for integrated technology-based toxicological and chemical evaluation of complex mixtures of drinking water disinfection byproducts.

    PubMed

    Simmons, Jane Ellen; Richardson, Susan D; Speth, Thomas F; Miltner, Richard J; Rice, Glenn; Schenck, Kathleen M; Hunter, E Sidney; Teuschler, Linda K

    2002-12-01

    Chemical disinfection of water is a major public health triumph of the 20th century. Dramatic decreases in both morbidity and mortality of waterborne diseases are a direct result of water disinfection. With these important public health benefits comes low-level, chronic exposure to a very large number of disinfection byproducts (DBPs), chemicals formed through reaction of the chemical disinfectant with naturally occurring inorganic and organic material in the source water. This article provides an overview of joint research planning by scientists residing within the various organizations of the U.S. Environmental Protection Agency Office of Research and Development. The purpose is to address concerns related to potential health effects from exposure to DBPs that cannot be addressed directly from toxicological studies of individual DBPs or simple DBP mixtures. Two factors motivate the need for such an investigation of complex mixtures of DBPs: a) a significant amount of the material that makes up the total organic halide and total organic carbon portions of the DBPs has not been identified; and b) epidemiologic data, although not conclusive, are suggestive of potential developmental, reproductive, or carcinogenic health effects in humans exposed to DBPs. The plan is being developed and the experiments necessary to determine the feasibility of its implementation are being conducted by scientists from the National Health and Environmental Effects Research Laboratory, the National Risk Management Research Laboratory, the National Exposure Research Laboratory, and the National Center for Environmental Assessment. PMID:12634133

  13. The toxicity of a new disinfection by-product, 2,2-dichloroacetamide (DCAcAm), on adult zebrafish (Danio rerio) and its occurrence in the chlorinated drinking water.

    PubMed

    Yu, Shilin; Lin, Tao; Chen, Wei; Tao, Hui

    2015-11-01

    The detection method of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product (DBP) in chlorinated drinking water, was established using a gas chromatograph coupled with a micro-electron capture detector. The chlorinated water samples were taken from ten drinking water treatment plants around Yangtze River or Taihu Lake in China. The concentration of DCAcAm was detected ranging from 0.5 to 1.8μg/L in the waterworks around Yangtze River, and 1.5-2.6μg/L around Taihu Lake. The toxicity of DCAcAm on adult zebrafish was assessed by investigating the metabolism damage with multiple metabolic biomarkers and the accumulation capability with bio-concentration factor. The results showed that DCAcAm could cause the acute metabolism damage and was easily accumulated in zebrafish, and should be extremely cautioned.

  14. The toxicity of a new disinfection by-product, 2,2-dichloroacetamide (DCAcAm), on adult zebrafish (Danio rerio) and its occurrence in the chlorinated drinking water.

    PubMed

    Yu, Shilin; Lin, Tao; Chen, Wei; Tao, Hui

    2015-11-01

    The detection method of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product (DBP) in chlorinated drinking water, was established using a gas chromatograph coupled with a micro-electron capture detector. The chlorinated water samples were taken from ten drinking water treatment plants around Yangtze River or Taihu Lake in China. The concentration of DCAcAm was detected ranging from 0.5 to 1.8μg/L in the waterworks around Yangtze River, and 1.5-2.6μg/L around Taihu Lake. The toxicity of DCAcAm on adult zebrafish was assessed by investigating the metabolism damage with multiple metabolic biomarkers and the accumulation capability with bio-concentration factor. The results showed that DCAcAm could cause the acute metabolism damage and was easily accumulated in zebrafish, and should be extremely cautioned. PMID:26037958

  15. The Recreational Water Cycle: From Source Water to Tap Water to Spa and Swimming Pool Water: Effects of Disinfectants and Precursors and Implications for Exposure and Toxicity

    EPA Science Inventory

    The current study investigates the effect of different disinfection treatments on the disinfection by-products (DBPs) formed in finished drinking water vs. tap water vs. swimming pool water vs. spa waters. To this end, complete water pathway samples (untreated source waters ->fi...

  16. Integrated Multidisciplinary Assessment of Environmentally Realistic Complex Mixtures of Drinking Water Disinfection ByProducts (DBPs) (The 4Lab Study)

    EPA Science Inventory

    More than 600 DBPs have been identified; yet ~50% of the total organic halide from chlorination is unidentified. Epidemiology studies suggest associations between human use of chlorinated water and reproductive/developmental effects (pregnancy loss, low birth weight), that are un...

  17. THE CARCINOGENIC RESPONSE OF TSC2 MUTANT LONG EVANS (EKER) RATS TO A MIXTURE OF DRINKING WATER DISINFECTION BY-PRODUCTS WAS LESS THAN ADDITIVE

    EPA Science Inventory

    Cancer risk assessment methods for chemical mixtures in drinking water are not well defined. Current default risk assessments for chemical mixtures assume additivity of carcinogenic effects but this may not represent the actual biological response. A rodent model of hereditary ...

  18. Prediction of the developmental toxicity hazard potential of halogenated drinking water disinfection by-products tested by the in vitro hydra assay

    SciTech Connect

    Fu, L.J.; Johnson, E.M.; Newman, L.M. )

    1990-06-01

    A series of seven randomly selected potential halogenated water disinfection by-products were evaluated in vitro by the hydra assay to determine their developmental toxicity hazard potential. For six of the chemicals tested by this assay (dibromoacetonitrile; trichloroacetonitrile; 2-chlorophenol; 2,4,6-trichlorophenol; trichloroacetic acid; dichloroacetone) it was predicted that they would be generally equally toxic to both adult and embryonic mammals when studied by means of standard developmental toxicity teratology tests. However, the potential water disinfection by-product chloroacetic acid (CA) was determined to be over eight times more toxic to the embryonic developmental portion of the assay than it was to the adults. Because of this potential selectivity, CA is a high-priority item for developmental toxicity tests in pregnant mammals to confirm or refute its apparent unique developmental hazard potential and/or to establish a NOAEL by the route of most likely human exposure.

  19. AOPs with ozone and UV radiation in drinking water: contaminants removal and effects on disinfection byproducts formation.

    PubMed

    Collivignarelli, C; Sorlini, S

    2004-01-01

    In this study, the advanced oxidation with ozone and UV radiation (with two low pressure UV lamps, at 254 and 185 nm wavelength) were experimented on a surface water in order to study the removal of two odorous compounds (geosmin and 2-methylisoborneol) and a pesticide (metolachlor), the influence on organic compounds (UV absorbance and THM precursors) and bromate formation. Different batch tests were performed with ozone concentration up to 10 mg/L, UV dose up to 14,000 J/m2 and a maximum contact time of 10 minutes. The main results show that metolachlor can be efficiently removed with ozone alone while for geosmin and MIB a complete removal can be obtained with the advanced oxidation of ozone (with concentration of 1.5-3 mg/L and contact time of 2-3 minutes) with UV radiation (with doses of 5,000-6,000 J/m2). As concerns the influence on the organic precursors, all the experimented processes show a medium removal of about 20-40% for UV absorbance and 15-30% for THMFP (trihalomethanes formation potential). As concerns bromate formation, the advanced oxidation of ozone/UV 254 nm shows a bromate formation that is about 40% lower with respect to conventional oxidation with ozone.

  20. Alternative disinfectant water treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternative disinfestant water treatments are disinfestants not as commonly used by the horticultural industry. Chlorine products that produce hypochlorous acid are the main disinfestants used for treating irrigation water. Chlorine dioxide will be the primary disinfestant discussed as an alternativ...

  1. A review of heterogeneous photocatalysis for water and surface disinfection.

    PubMed

    Byrne, John Anthony; Dunlop, Patrick Stuart Morris; Hamilton, Jeremy William John; Fernández-Ibáñez, Pilar; Polo-López, Inmaculada; Sharma, Preetam Kumar; Vennard, Ashlene Sarah Margaret

    2015-03-30

    Photo-excitation of certain semiconductors can lead to the production of reactive oxygen species that can inactivate microorganisms. The mechanisms involved are reviewed, along with two important applications. The first is the use of photocatalysis to enhance the solar disinfection of water. It is estimated that 750 million people do not have accessed to an improved source for drinking and many more rely on sources that are not safe. If one can utilize photocatalysis to enhance the solar disinfection of water and provide an inexpensive, simple method of water disinfection, then it could help reduce the risk of waterborne disease. The second application is the use of photocatalytic coatings to combat healthcare associated infections. Two challenges are considered, i.e., the use of photocatalytic coatings to give "self-disinfecting" surfaces to reduce the risk of transmission of infection via environmental surfaces, and the use of photocatalytic coatings for the decontamination and disinfection of medical devices. In the final section, the development of novel photocatalytic materials for use in disinfection applications is reviewed, taking account of materials, developed for other photocatalytic applications, but which may be transferable for disinfection purposes.

  2. ATRAZOME CHLORINATION TRANSFORMATION PRODUCTS UNDER DRINKING WATER DISTRIBUTION SYSTEM CONDITIONS

    EPA Science Inventory

    Chlorination is a commonly-used disinfectant step in drinking water treatment. Should free chlorine be added to water used as a drinking water source, it is widely understood that many biological species in the water, along with dissolved organic and inorganic chemicals, will rea...

  3. Sources and characteristics of organic matter in the Clackamas River, Oregon, related to the formation of disinfection by-products in treated drinking water

    USGS Publications Warehouse

    Carpenter, Kurt D.; Kraus, Tamara E.C.; Goldman, Jami H.; Saraceno, John Franco; Downing, Bryan D.; Bergamaschi, Brian A.; McGhee, Gordon; Triplett, Tracy

    2013-01-01

    This study characterized the amount and quality of organic matter in the Clackamas River, Oregon, to gain an understanding of sources that contribute to the formation of chlorinated and brominated disinfection by-products (DBPs), focusing on regulated DBPs in treated drinking water from two direct-filtration treatment plants that together serve approximately 100,000 customers. The central hypothesis guiding this study was that natural organic matter leaching out of the forested watershed, in-stream growth of benthic algae, and phytoplankton blooms in the reservoirs contribute different and varying proportions of organic carbon to the river. Differences in the amount and composition of carbon derived from each source affects the types and concentrations of DBP precursors entering the treatment plants and, as a result, yield varying DBP concentrations and species in finished water. The two classes of DBPs analyzed in this study-trihalomethanes (THMs) and haloacetic acids (HAAs)-form from precursors within the dissolved and particulate pools of organic matter present in source water. The five principal objectives of the study were to (1) describe the seasonal quantity and character of organic matter in the Clackamas River; (2) relate the amount and composition of organic matter to the formation of DBPs; (3) evaluate sources of DBP precursors in the watershed; (4) assess the use of optical measurements, including in-situ fluorescence, for estimating dissolved organic carbon (DOC) concentrations and DBP formation; and (5) assess the removal of DBP precursors during treatment by conducting treatability "jar-test" experiments at one of the treatment plants. Data collection consisted of (1) monthly sampling of source and finished water at two drinking-water treatment plants; (2) event-based sampling in the mainstem, tributaries, and North Fork Reservoir; and (3) in-situ continuous monitoring of fluorescent dissolved organic matter (FDOM), turbidity, chlorophyll-a, and

  4. Sources and characteristics of organic matter in the Clackamas River, Oregon, related to the formation of disinfection by-products in treated drinking water

    USGS Publications Warehouse

    Carpenter, Kurt D.; Kraus, Tamara E.C.; Goldman, Jami H.; Saraceno, John Franco; Downing, Bryan D.; Bergamaschi, Brian A.; McGhee, Gordon; Triplett, Tracy

    2013-01-01

    This study characterized the amount and quality of organic matter in the Clackamas River, Oregon, to gain an understanding of sources that contribute to the formation of chlorinated and brominated disinfection by-products (DBPs), focusing on regulated DBPs in treated drinking water from two direct-filtration treatment plants that together serve approximately 100,000 customers. The central hypothesis guiding this study was that natural organic matter leaching out of the forested watershed, in-stream growth of benthic algae, and phytoplankton blooms in the reservoirs contribute different and varying proportions of organic carbon to the river. Differences in the amount and composition of carbon derived from each source affects the types and concentrations of DBP precursors entering the treatment plants and, as a result, yield varying DBP concentrations and species in finished water. The two classes of DBPs analyzed in this study-trihalomethanes (THMs) and haloacetic acids (HAAs)-form from precursors within the dissolved and particulate pools of organic matter present in source water. The five principal objectives of the study were to (1) describe the seasonal quantity and character of organic matter in the Clackamas River; (2) relate the amount and composition of organic matter to the formation of DBPs; (3) evaluate sources of DBP precursors in the watershed; (4) assess the use of optical measurements, including in-situ fluorescence, for estimating dissolved organic carbon (DOC) concentrations and DBP formation; and (5) assess the removal of DBP precursors during treatment by conducting treatability "jar-test" experiments at one of the treatment plants. Data collection consisted of (1) monthly sampling of source and finished water at two drinking-water treatment plants; (2) event-based sampling in the mainstem, tributaries, and North Fork Reservoir; and (3) in-situ continuous monitoring of fluorescent dissolved organic matter (FDOM), turbidity, chlorophyll-a, and

  5. ALTERNATIVE DISINFECTANTS FOR DRINKING WATER

    EPA Science Inventory

    Using a combination of spectral identification techniques - gas chromatography coupled with low-and high-resolution electron-impact mass spectrometry (GC/EI-MS), low-and high-resolution chemical ionization mass spectrometry (GC/CI-MS), and Fourier transform infrared spectroscopy ...

  6. Comparison of DNA damage in human-derived hepatoma line (HepG2) exposed to the fifteen drinking water disinfection byproducts using the single cell gel electrophoresis assay.

    PubMed

    Zhang, Li; Xu, Liang; Zeng, Qiang; Zhang, Shao-Hui; Xie, Hong; Liu, Ai-Lin; Lu, Wen-Qing

    2012-01-24

    Disinfection of drinking water reduces pathogenic infection, but generates disinfection by-products (DBPs) in drinking water. In this study, the effect of fifteen DBPs on DNA damage in human-derived hepatoma line (HepG2) was investigated by the single cell gel electrophoresis (SCGE) assay. These fifteen DBPs are: four trihalomethanes (THMs), six haloacetic acides (HAAs), three haloacetonitriles (HANs), 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), and chloral hydrate (CH). Based on the minimal effective concentration (MEC) at which DBPs induced significant increase in olive tail moment (OTM), the rank order of DNA-damaging potency is: bromodichloromethane (BDCM)>dibromochloromethane (DBCM)>tribromomethane (TBM)>trichloromethane (TCM) of the four THMs; iodoacetic acid (IA)>bromoacetic acid (BA)>dibromoacetic acid (DBA)>dichloracetic acid (DCA)>trichloroacetic acid (TCA) of the five HAAs; dibromoacetonitrile (DBN)approximately dichloroacetonitrile (DCN)>trichloroacetonitrile (TCN) of the three HANs. The DNA damaging potency of MX and CH is similar to TCA and DCA, respectively. IA is the most genotoxic DBP in the fifteen DBPs, followed by BA. Chloroacetic acid (CA) is not genotoxic in this assay. Our findings indicated that HepG2/SCGE is a sensitive tool to evaluate the genotoxicity of DBPs and iodinated DBPs are more genotoxic than brominated DBPs, but chlorinated DBPs are less genotoxic than brominated DBPs.

  7. Safe drinking water: the toxicologist's approach.

    PubMed

    van Leeuwen, F X

    2000-01-01

    The production of adequate and safe drinking water is a high priority issue for safeguarding the health and well-being of humans all over the world. Traditionally, microbiological quality of drinking water has been the main concern, but over the last decades the attention of the general public and health officials on the importance of chemical quality and the threat of chemical pollutants have increased with the increase of our knowledge on the hazards of chemical substances. There are many sources of contamination of drinking water. Broadly they can be divided into two categories: contaminants originating from surface and groundwater, and contaminants used or formed during the treatment and distribution of drinking water. Contaminants in surface and groundwater can range from natural substances such as arsenic and manganese leaching from soil, to contaminants introduced by human activities, such as run-off from agricultural activities, controlled discharge from sewage treatment works and industrial plants, and uncontrolled discharges or leakage from landfill sites and from chemical accidents. Disinfectants and disinfectant by-products are well known contaminants resulting from the processes used by the drinking water industry for the treatment and distribution of water. The basic question in the production of drinking water is how to rid drinking water of potentially dangerous microorganisms and chemicals without introducing new hazards that might pose new and different threats to human health. It is the responsibility of toxicologists to provide risk assessments for chemical pollutants and to derive guidelines or standards for drinking water quality below which no significant health risk is encountered, to assure consumers that drinking water is safe and can be consumed without any risk. This paper will focus on the toxicological procedures used by the World Health Organization to derive guideline values for chemical compounds in drinking water, and will touch

  8. Silver disinfection in water distribution systems

    NASA Astrophysics Data System (ADS)

    Silvestry Rodriguez, Nadia

    Silver was evaluated as disinfectant to maintain water quality in water distribution system. It was used to inhibit growth of two opportunistic bacteria in planktonik form and in biofilm formation in Robbins devices with stainless steel and PVC surfaces. The results of this work show that silver is a potential secondary disinfectant to be used in water distribution systems.

  9. DBP CONTROL IN DRINKING WATER: COST AND PERFORMANCE

    EPA Science Inventory

    The U.S. Environmental Protection Agency (U.S. EPA) is currently attempting to balance the complex trade-offs in chemical and microbial risks associated with controlling disinfection and disinfection byproducts (D/DBP) in drinking water. In attempting to achieve this balance, the...

  10. TECHNIQUES FOR ANALYZING COMPLEX MIXTURES OF DRINKING WATER DBPS

    EPA Science Inventory

    Although chlorine has been used to disinfect drinking water for approximately 100 years, there have been concerns raised over its use, due to the formation of potentially hazardous by-products. Trihalomethanes (THMs) were the first disinfection by-products (DBPs) identified and ...

  11. Water, Water Everywhere, But is it Safe to Drink?

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) have been associated with adverse human health effects, including bladder cancer, early term miscarriage, and birth defects. While it is vitally important to kill harmful pathogens in water, it is also important to minimize harmful ...

  12. Quality of Drinking Water

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2009-01-01

    The quality of drinking water has been gaining a great deal of attention lately, especially as water delivery infrastructure continues to age. Particles of various metals such as lead and copper, and other substances like radon and arsenic could be entering drinking water supplies. Spilled-on-the-ground hydrocarbon-based substances are also…

  13. Bilogical Treatment for Ammonia Oxidation in Drinking Water Facilities

    EPA Science Inventory

    Ammonia is an unregulated compound, but is naturally occurring in many drinking water sources. It is also used by some treatment facilities to produce chloramines for disinfection purposes. Because ammonia is non-toxic, its presence in drinking water is often disregarded. Thro...

  14. NEUROXOTOXICITY PRODUCED BY DIBROMOACETIC ACID IN DRINKING WATER OF RATS.

    EPA Science Inventory

    The Safe Drinking Water Act requires that EPA consider noncancer endpoints for the assessment of adverse human health effects of disinfection byproducts (DBPs). Dibromoacetic acid (DBA) is one of many DBPs produced by the chlorination of drinking water. Its chlorinated analog, ...

  15. IDENTIFICATION OF NEW BROMINATED ACIDS IN DRINKING WATER

    EPA Science Inventory

    Since chloroform was identified as the first disinfection by-product (DBP) in drinking water, there has been more than 25 years of research on DBPs. Despite these efforts, more than 50% of the total organic halide (TOX) formed in chlorinated drinking water remains unknown. Ther...

  16. Drinking-water standards

    SciTech Connect

    Munro, N.B.; Travis, C.C.

    1986-08-01

    This paper discussed the revising of the primary and secondary drinking-water regulations by EPA in accordance with the Safe Drinking Water Act. Since consideration of risk is playing an increasing role in setting environmental standards, questions were raised regarding the adequacy of human health protection afforded by some of the existing and proposed standards. 1 table.

  17. Drinking Water and Health.

    ERIC Educational Resources Information Center

    National Academy of Sciences, Washington, DC.

    In response to a provision of the Safe Drinking Water Act of 1974 which called for a study that would serve as a scientific basis for revising the primary drinking water regulations that were promulgated under the Act, a study of the scientific literature was undertaken in order to assess the implications for human health of the constituents of…

  18. Drinking water microbial myths.

    PubMed

    Allen, Martin J; Edberg, Stephen C; Clancy, Jennifer L; Hrudey, Steve E

    2015-01-01

    Accounts of drinking water-borne disease outbreaks have always captured the interest of the public, elected and health officials, and the media. During the twentieth century, the drinking water community and public health organizations have endeavored to craft regulations and guidelines on treatment and management practices that reduce risks from drinking water, specifically human pathogens. During this period there also evolved misunderstandings as to potential health risk associated with microorganisms that may be present in drinking waters. These misunderstanding or "myths" have led to confusion among the many stakeholders. The purpose of this article is to provide a scientific- and clinically-based discussion of these "myths" and recommendations for better ensuring the microbial safety of drinking water and valid public health decisions.

  19. Fungi contamination of drinking water.

    PubMed

    Al-Gabr, Hamid Mohammad; Zheng, Tianling; Yu, Xin

    2014-01-01

    Aquatic fungi commonly infest various aqueous environments and play potentially crucial roles in nutrient and carbon cycling. Aquatic fungi also interact with other organisms to influence food web dynamics. In recent decades, numerous studies have been conducted to address the problem of microorganism contamination of water. The major concern has been potential effects on human health from exposure to certain bacteria, viruses, and protozoa that inhabit water and the microbial metabolites,pigments, and odors which are produced in the water, and their effects on human health and animals. Fungi are potentially important contaminants because they produce certain toxic metabolites that can cause severe health hazards to humans and animals. Despite the potential hazard posed by fungi, relatively few studies on them as contaminants have been reported for some countries.A wide variety of fungi species have been isolated from drinking water, and some of them are known to be strongly allergenic and to cause skin irritation, or immunosuppression in immunocompromised individuals (e.g., AIDS, cancer, or organ transplant patients). Mycotoxins are naturally produced as secondary metabolites by some fungi species, and exposure of humans or animals to them can cause health problems. Such exposure is likely to occur from dietary intake of either food,water or beverages made with water. However, mycotoxins, as residues in water,may be aerosolized when showering or when being sprayed for various purposes and then be subject to inhalation. Mycotoxins, or at least some of them, are regarded to be carcinogenic. There is also some concern that toxic mycotoxins or other secondary metabolites of fungi could be used by terrorists as a biochemical weapon by adding amounts of them to drinking water or non drinking water. Therefore, actions to prevent mycotoxin contaminated water from affecting either humans or animals are important and are needed. Water treatment plants may serve to partially

  20. ANALYTICAL METHODS FOR WATER DISINFECTION BY-PRODUCTS IN FOODS AND BEVERAGES

    EPA Science Inventory

    The determination of exposure to drinking water disinfection byproducts (DBPs) requires an understanding of how drinking water comes in contact with humans through multiple pathways. In order to facilitate the investigation of human exposure to DBPs via foods and beverages, analy...

  1. The use of ozonation and catalytic ozonation combined with ultrafiltration for the control of natural organic matter (NOM) and disinfection by-products (DBPs) in drinking water

    NASA Astrophysics Data System (ADS)

    Karnik, Bhavana Sushilkumar

    Commercially available titania membranes, with a molecular weight cut-off of 15, 5, 1 kD were used in a ozonation/membrane system that was fed with water from Lake Lansing. The effects of ozonation on permeate flux recovery and membrane fouling was investigated. In addition the effects of ozonation/membrane filtration hybrid process on the removal of the natural organic matter (NOM) and the formation of disinfection by-products (DBPS) were monitored. The commercial membrane (CeRAM Inside, Tami North America, St. Laurent, Quebec, Canada) was coated with iron oxide nanoparticles (4--6 nm in diameter) using a layer-by-layer technique and sintered in air for 30 minutes. Surface characterization was carried out using electron microscopy techniques and atomic force microscopy, to study the changes in structure and surface morphology of the membranes. The removal and survival of bacteria in the process was also evaluated using fluorescence microscopy and microbial assays. Finally the surface catalytic reaction was investigated to propose the mechanism responsible for the improved performance of the hybrid process. The permeate flux through a titania coated ceramic membrane was significantly affected by ozonation. A minimum threshold ozone concentration (2.5 g/m 3) could achieve complete recovery of permeate flux after fouling. Ozonation/filtration decreased the concentration of chlorinated disinfection by-products up to 80%. With catalyst coated membranes, the concentration of dissolved organic carbon was reduced by >85% and the concentrations of disinfection by-products decreased by up to 90%. Furthermore with the coated membrane, the concentrations of ozonation by-products in the permeate were reduced by >50% as compared to that obtained with the uncoated membranes, thus reducing the risk of potential regrowth of bacteria in the distribution system. Application of the hybrid process lead to greater than 7 log removal of bacteria. Surface characterization showed that

  2. THE USE OF MODELS FOR GRANTING VARIANCES FROM MANDATORY DISINFECTION OF GROUND WATER USED AS A PUBLIC WATER SUPPLY

    EPA Science Inventory

    In November 1985, a Maximum Contaminant Level Goal of zero viruses in drinking water was published. By 1991, the U.S. Environmental Protection Agency Office of Drinking Water to promulgate regulations requiring that all ground water used for potable purposes disinfected prior to ...

  3. The impact of commercially treated oil and gas produced water discharges on bromide concentrations and modeled brominated trihalomethane disinfection byproducts at two downstream municipal drinking water plants in the upper Allegheny River, Pennsylvania, USA.

    PubMed

    Landis, Matthew S; Kamal, Ali S; Kovalcik, Kasey D; Croghan, Carry; Norris, Gary A; Bergdale, Amy

    2016-01-15

    In 2010, a dramatic increase in the levels of total trihalomethane (THM) and the relative proportion of brominated species was observed in finished water at several Pennsylvania water utilities (PDW) using the Allegheny River as their raw water supply. An increase in bromide (Br(-)) concentrations in the Allegheny River was implicated to be the cause of the elevated water disinfection byproducts. This study focused on quantifying the contribution of Br(-) from a commercial wastewater treatment facility (CWTF) that solely treats wastes from oil and gas producers and discharges into the upper reaches of the Allegheny River, and impacts on two downstream PDWs. In 2012, automated daily integrated samples were collected on the Allegheny River at six sites during three seasonal two-week sampling campaigns to characterize Br(-) concentrations and river dispersion characteristics during periods of high and low river discharges. The CWTF discharges resulted in significant increases in Br(-) compared to upstream baseline values in PDW raw drinking water intakes during periods of low river discharge. During high river discharge, the assimilative dilution capacity of the river resulted in lower absolute halide concentrations, but significant elevations Br(-) concentrations were still observed at the nearest downstream PDW intake over baseline river levels. On days with active CWTF effluent discharge the magnitude of bromide impact increased by 39 ppb (53%) and 7 ppb (22%) for low and high river discharge campaigns, respectively. Despite a declining trend in Allegheny River Br(-) (2009-2014), significant impacts from CWTF and coal-fired power plant discharges to Br(-) concentrations during the low river discharge regime at downstream PDW intakes was observed, resulting in small modeled increases in total THM (3%), and estimated positive shifts (41-47%) to more toxic brominated THM analogs. The lack of available coincident measurements of THM, precursors, and physical parameters

  4. The impact of commercially treated oil and gas produced water discharges on bromide concentrations and modeled brominated trihalomethane disinfection byproducts at two downstream municipal drinking water plants in the upper Allegheny River, Pennsylvania, USA.

    PubMed

    Landis, Matthew S; Kamal, Ali S; Kovalcik, Kasey D; Croghan, Carry; Norris, Gary A; Bergdale, Amy

    2016-01-15

    In 2010, a dramatic increase in the levels of total trihalomethane (THM) and the relative proportion of brominated species was observed in finished water at several Pennsylvania water utilities (PDW) using the Allegheny River as their raw water supply. An increase in bromide (Br(-)) concentrations in the Allegheny River was implicated to be the cause of the elevated water disinfection byproducts. This study focused on quantifying the contribution of Br(-) from a commercial wastewater treatment facility (CWTF) that solely treats wastes from oil and gas producers and discharges into the upper reaches of the Allegheny River, and impacts on two downstream PDWs. In 2012, automated daily integrated samples were collected on the Allegheny River at six sites during three seasonal two-week sampling campaigns to characterize Br(-) concentrations and river dispersion characteristics during periods of high and low river discharges. The CWTF discharges resulted in significant increases in Br(-) compared to upstream baseline values in PDW raw drinking water intakes during periods of low river discharge. During high river discharge, the assimilative dilution capacity of the river resulted in lower absolute halide concentrations, but significant elevations Br(-) concentrations were still observed at the nearest downstream PDW intake over baseline river levels. On days with active CWTF effluent discharge the magnitude of bromide impact increased by 39 ppb (53%) and 7 ppb (22%) for low and high river discharge campaigns, respectively. Despite a declining trend in Allegheny River Br(-) (2009-2014), significant impacts from CWTF and coal-fired power plant discharges to Br(-) concentrations during the low river discharge regime at downstream PDW intakes was observed, resulting in small modeled increases in total THM (3%), and estimated positive shifts (41-47%) to more toxic brominated THM analogs. The lack of available coincident measurements of THM, precursors, and physical parameters

  5. Genotoxicity of Swimming Pool Water and Carcinogenicity of Drinking Water

    EPA Science Inventory

    Among the 11 disinfection by-products (DBPs) in drinking water that are regulated by the U.S. EPA, (a) 2 DBPs (chloroaceticacid and chlorite) are not carcinogenic-in either of2 species; (b) chlorite is not carcinogenic in 3 rodent assays and has never been tested for genotoxicity...

  6. Genotoxicity of Swimming Pool Water and Carcinogenicity of Drinking Water**

    EPA Science Inventory

    Among the 11 disinfection by-products (DBPs) in drinking water that are regulated by the U.S. EPA, (a) 2 DBPs (chloroaceticacid and chlorite) are not carcinogenic-in either of2 species; (b) chlorite is not carcinogenic in 3 rodent assays and has never been tested for genotoxicity...

  7. [Drinking water in infants].

    PubMed

    Vitoria Miñana, I

    2004-02-01

    We review types of public drinking water and bottled water and provide recommendations on the composition of water for infants. Water used with any of the commercial infant formulas in Spain should contain less than 25 mg/l of sodium. Drinking water must be boiled for a maximum of one minute (at sea level) to avoid excessive salt concentration. Bottled water need not be boiled. Fluoride content in drinking water should be less than 0.3 mg/l in first year of life to prevent dental fluorosis. Nitrate content in water should be less than 25 mg/l to prevent methemoglobinemia. Water with a calcium concentration of between 50 and 100 mg/l is a dietary source of calcium since it provides 24-56 % of the required daily intake in infancy.

  8. MONOCHLORAMINE MICROELECTRODE FOR IN SITU APPLICATION WITHIN THE BIOFILM OF CHLORAMINATED DRINKING WATER DISTRIBUTION SYSTEMS- Abstract

    EPA Science Inventory

    Many utilities in the United States are using monochloramine as a secondary disinfectant as a result of the implementation of the Stage 1 and Stage 2 Disinfectants and Disinfection Byproduct Rules. A recent survey suggests that an additional 12% of drinking water utilities are c...

  9. Changes in Biofilm Community Structure Associated with Monochloramine-treated Drinking Water Biofilms

    EPA Science Inventory

    Monochloramine is increasingly used as a drinking water disinfectant because it forms lower levels of traditional disinfectant by-products compared to free-chlorine disinfection treatment. The use of monochloramine has been shown to increase ammonia-oxidizing bacteria and the pr...

  10. A novel fiber optical device for ultraviolet disinfection of water.

    PubMed

    Lu, Gang; Li, Chaolin; Zheng, Yinggang; Zhang, Qian; Peng, Juan; Fu, Ming

    2008-07-24

    Since there are several problems in traditional UV disinfection techniques, a highly efficient, reliable and economical method, using quartz optical fibers to deliver UV light is proposed. The principle of the experimental setup is that ultraviolet rays are gathered by a reflector and converge on a light point, the diameter of approximately 5mm. In this way UV light can be transferred into water to kill the bacteria in the water. This paper presents preliminary results on water disinfection using this new UV disinfection setup. Its suitability for application could be shown in experiments with E. coli (ATCC8099) as test microorganisms. We have optimized the distribution of the optical fibers in the water in bench-scale study. This result can provide guidance for pilot-scale and field-scale study of this new technique. The results show that the new technique had a good performance under different conditions as follows: (a) turbidity level=10.2 NTU, (b) ferric ion concentration=0.3 mg/L, and (c) humic acid concentration=5 mg/L. The new technique provides a promising approach to disinfection treatment of drinking water.

  11. Subacute toxicity assessment of water disinfection byproducts on zebrafish.

    PubMed

    Rácz, Gergely; Csenki, Zsolt; Kovács, Róbert; Hegyi, Arpád; Baska, Ferenc; Sujbert, László; Zsákovics, Ivett; Kis, Renáta; Gustafson, Ryan; Urbányi, Béla; Szende, Béla

    2012-07-01

    Disinfection of raw water is essential to the production of drinking water. However, by-products of disinfection may exert toxic effects. The potential toxic effects of two of these compounds, 4-ethylbenzaldehyde (EBA) and 2,4-difluoroaniline (DFA) were investigated using the zebrafish (Danio rerio) model. The two compounds, dissolved, were introduced in duplicate aquariums containing zebrafish in two different concentrations based on LC50 values. The aquarium water containing EBA or DFA was changed every 96 h throughout the 3 months of treatment. Behavior of the fish in each replicate was inspected twice daily. In course of treatment with both concentrations, fish exposed to DFA displayed behavior associated with visible anxiety, while EBA treated were lethargic and did not evade capture. Application of both concentrations of each component into the aquarium water resulted in dystrophic lesions in the liver, kidney and skin of the fish while preneoplastic lesions and tumors were not observed. PMID:22161134

  12. Installation of a water disinfection system in a Mexico City hospital.

    PubMed

    Juárez Mendoza, J; Martínez Rosales, G; Díaz Sánchez, J; Brust Mascher, E; Brust Carmona, H

    1992-01-01

    With a view to evaluating a small-scale water disinfection system based on production and application of oxidizing gases, the level of equivalent residual chlorine and the degree of contamination by fecal and total coliform bacteria was assessed at various points in the drinking water system of a Mexico City hospital before and after installation of the disinfection equipment. Tests done in May and June 1989, prior to installation of the equipment, showed that residual chlorine concentrations were lower than the national standard in most of the samples and that a sizable portion of these samples were also contaminated with fecal and total coliform concentrations exceeding national standards. After installation of the disinfection system at the main inflow to the hospital's drinking water supply in August 1989, the equivalent residual chlorine concentrations were found adequate and no coliform bacteria were detected. These results indicate that the oxidant mixture generated by the newly installed system was effectively disinfecting the water.

  13. [Drinking water and parasites].

    PubMed

    Karanis, P; Schoenen, D; Maier, W A; Seitz, H M

    1993-10-01

    Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum, Isospora belli, Balantidium coli, and Microsporidia spp. are cosmopolitan parasites. They often cause diarrheal diseases. The waterborn transmission of all these parasites is possible (41). Surface water supplies used for drinking water are potential sources of contamination. Giardia lamblia and Cryptosporidium spp. have received great attention in industrialized countries during the last years because they are the etiological agents of waterborne diseases. The life cycles of Giardia lamblia and Cryptosporidium are described with a special reference to drinking water technologies aimed at removing these parasites. PMID:8253478

  14. REGULATED CONTAMINANTS IN DRINKING WATER

    EPA Science Inventory

    Safe drinking water is critical to protecting human health. More than 260 million Americans rely on the safety of tap water provided by water systems that comply with national drinking water standards. EPA's strategy for ensuring safe drinking water includes four key elements, ...

  15. [Herbicides in drinking water].

    PubMed

    Funari, E; Sampaolo, A

    1989-01-01

    Toxicological implications due to the use of herbicide-contaminated drinking water, as well as other organic chemicals, are related to their nature and levels. These implications can be defined for each substance on the basis of an adequate evaluation of epidemiological information and experimental data on animals. In this paper, World Health Organization's procedures for establishing guidelines for 11 herbicides widely used in Italy are described. Furthermore, data and information about the use of these herbicides and their levels in Italian drinking-water supplies are also reported and discussed. Finally, factors and conditions responsible for the groundwater contamination by some herbicides in determined areas are presented and discussed.

  16. MODERATING INFLUENCE OF THE DRINKING WATER DISINFECTION BY-PRODUCT DIBROMOACETIC ACID ON A DITHIOCARBAMATE-INDUCED SUPPRESSION OF THE LUTEINIZING HORMONE SURGE IN FEMALE RATS.

    EPA Science Inventory

    The disinfection by-product dibromoacetic acid (DBA) has been found in female rats to increase circulating concentrations of both estradiol (E2) and estrone (E1). This effect is apparently due, at least in part, to a suppression in hepatic catabolism. The present study investigat...

  17. A Long-Term Study of the Microbial Community Structure in a Simulated Chloraminated Drinking Water Distribution System

    EPA Science Inventory

    Free chlorine is used as the primary disinfectant in most drinking water distribution systems(DWDS). However, chlorine disinfection promotes the formation of disinfectant by-products (DBPs)and as a result, many US water treatment facilities use chloramination to ensure regulatory...

  18. Ultraviolet disinfection of water for small water supplies

    NASA Astrophysics Data System (ADS)

    Carlson, D. A.; Seabloom, R. W.; Dewalle, F. B.; Wetzler, T. F.; Engeset, J.

    1985-07-01

    In the study ultraviolet radiation was considered as an alternative means of disinfection of small drinking water supplies. A major impetus for the study was the large increase in waterborne disease episodes in the United States whose etiologic agent, Giardia lamblia, was found to be highly resistant to conventional chlorination. While the germicidal effect of sunlight has long been known, it has been found that artificial UV radiation with a wavelength of 253.7 nm, can be produced by low pressure mercury vapor lamps. The inactivation of microorganisms by UV radiation is based upon photochemical reactions in DNA which result in errors in the coding system. Inactivation of microorganisms due to exposure to UV is proportional to the intensity multiplied by the time of exposure.

  19. Chlorine stress mediates microbial surface attachment in drinking water systems.

    PubMed

    Liu, Li; Le, Yang; Jin, Juliang; Zhou, Yuliang; Chen, Guowei

    2015-03-01

    Microbial attachment to drinking water pipe surfaces facilitates pathogen survival and deteriorates disinfection performance, directly threatening the safety of drinking water. Notwithstanding that the formation of biofilm has been studied for decades, the underlying mechanisms for the origins of microbial surface attachment in biofilm development in drinking water pipelines remain largely elusive. We combined experimental and mathematical methods to investigate the role of environmental stress-mediated cell motility on microbial surface attachment in chlorination-stressed drinking water distribution systems. Results show that at low levels of disinfectant (0.0-1.0 mg/L), the presence of chlorine promotes initiation of microbial surface attachment, while higher amounts of disinfectant (>1.0 mg/L) inhibit microbial attachment. The proposed mathematical model further demonstrates that chlorination stress (0.0-5.0 mg/L)-mediated microbial cell motility regulates the frequency of cell-wall collision and thereby controls initial microbial surface attachment. The results reveal that transport processes and decay patterns of chlorine in drinking water pipelines regulate microbial cell motility and, thus, control initial surface cell attachment. It provides a mechanistic understanding of microbial attachment shaped by environmental disinfection stress and leads to new insights into microbial safety protocols in water distribution systems.

  20. Attitudinal and Relational Factors Predicting the Use of Solar Water Disinfection: A Field Study in Nicaragua

    ERIC Educational Resources Information Center

    Altherr, Anne-Marie; Mosler, Hans-Joachim; Tobias, Robert; Butera, Fabrizio

    2008-01-01

    Solar water disinfection (SODIS) is an uncomplicated and cheap technology providing individuals with safe drinking water by exposing water-filled plastic bottles to sunlight for 6 hours to kill waterborne pathogens. Two communities were visited, and 81 families (40 SODIS users and 41 nonusers) were interviewed. The relationship between several…

  1. Virus contamination from operation and maintenance practices in small drinking water distribution systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the association of common events in drinking water distribution systems with contamination of household tap water with human enteric viruses. Viruses were enumerated by qPCR in the tap water of 14 municipal systems that use non-disinfected groundwater. Ultra-violet disinfection was install...

  2. Disinfection of water distribution systems for Legionella.

    PubMed

    Lin, Y S; Stout, J E; Yu, V L; Vidic, R D

    1998-06-01

    Hospital-acquired legionnaires' disease arises from the presence of Legionella in hospital water systems. Legionella not only persists in hot water tanks but is also found in the biofilm throughout the entire water distribution system. Conditions within water systems that promote Legionella colonization include water temperature, configuration and age of the hot water tank, physicochemical constituents of the water, plumbing materials, and commensal microflora. Hospital-acquired legionnaires' disease has been prevented by instituting control measures directed at the water distribution system. These include superheat-and-flush, copper/silver ionization, ultraviolet light, instantaneous heating systems, and hyperchlorination. Each of the above disinfection methods has been proven to be effective in the short-term, but long-term efficacy has been difficult due to limitations associated with each method. The complexities of Legionella disinfection, including advantages and disadvantages of each method, are reviewed. A successful Legionella prevention program requires cooperation and communication among hospital administrative personnel, engineers, and infection control staff. Routine environmental surveillance cultures for Legionella are the critical component for successful long-term disinfection. Culture results document the efficacy of the disinfection method and alert the hospital staff to consider Legionella in hospitalized patients with pneumonia. PMID:9643393

  3. DRINKING WATER ISSUES

    EPA Science Inventory

    According to recent reports by the California Department of Health Services, the State of Maine, and the United State Geological Survey (USGS); the fuel oxygenate methyl teri-butyl ether (MTBE) is present in 5 to 20 percent of the drinking water sources in California and the nort...

  4. Water Fit to Drink.

    ERIC Educational Resources Information Center

    Donovan, Edward P.

    The major objective of this module is to help students understand how water from a source such as a lake is treated to make it fit to drink. The module, consisting of five major activities and a test, is patterned after Individualized Science Instructional System (ISIS) modules. The first activity (Planning) consists of a brief introduction and a…

  5. Safe drinking water act: Amendments, regulations and standards

    SciTech Connect

    Calabrese, E.J.; Gilbert, C.E.; Pastides, H.

    1989-01-01

    This book approaches the topic of safe drinking water by communicating how the EPA has responded to the mandates of Congress. Chapter 1 summarizes what is and will be involved in achieving safe drinking water. Chapter 2 describes the historical development of drinking water regulations. Chapter 3 summarizes the directives of the Safe Drinking Water Act Amendments of 1986. Chapters 4 through 9 discuss each phase of the regulatory program in turn. Specific problems associated with volatile organic chemicals, synthetic organics, inorganic chemicals, and microbiological contaminants are assessed in Chapter 4 and 5. The unique characteristics of radionuclides and their regulation are treated in Chapter 6. The disinfection process and its resultant disinfection by-products are presented in Chapter 7. The contaminant selection process and the additional contaminants to be regulated by 1989 and 1991 and in future years are discussed in Chapters 8 and 9. EPA's Office of Drinking Water's Health Advisory Program is explained in Chapter 10. The record of public water system compliance with the primary drinking water regulations is detailed in Chapter 11. Chapter 12 offers a nongovernmental perspective on the general quality of drinking water and how this is affected by a wide range of drinking water treatment technologies. Separate abstracts are processed for 5 chapters in this book for inclusion in the appropriate data bases.

  6. Sources of chlorate ion in US drinking water

    SciTech Connect

    Bolyard, M. ); Fair, P.S. ); Hautman, D.P. )

    1993-09-01

    Samples of untreated source water and finished drinking water were obtained from 42 water utilities which treated their water with oxidants-disinfectants that included chlorine dioxide (ClO[sub 2]), gaseous chlorine, hypochlorite solutions, and chloramines. Chlorite ion was only detected in water from utilities that used ClO[sub 2]. Finished water from utilities that used ClO[sub 2] or hypochlorite solutions contained comparable concentrations of chlorate ion (ClO[sub 3][sup [minus

  7. Use of microbial risk assessment in setting US drinking water standards

    SciTech Connect

    Macier, B.A.; Regli, S.

    1992-10-01

    The paper outlines the U.S. EPA's general strategy for using microbial risk assessment to support the development of the National Primary Drinking Water Regulations. It discusses specifically the use of such risk assessment in the development of upcoming regulations for disinfection of groundwater and for control of disinfectants and their chemical byproducts, and possible amendments to the current Surface Water Treatment Rule.

  8. 40 CFR 141.541 - What are significant changes to disinfection practice?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... point of disinfection; (b) Changes to the disinfectant(s) used in the treatment plant; (c) Changes to... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration...

  9. 40 CFR 141.541 - What are significant changes to disinfection practice?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... point of disinfection; (b) Changes to the disinfectant(s) used in the treatment plant; (c) Changes to... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration...

  10. 40 CFR 141.541 - What are significant changes to disinfection practice?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... point of disinfection; (b) Changes to the disinfectant(s) used in the treatment plant; (c) Changes to... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration...

  11. Disinfection.

    ERIC Educational Resources Information Center

    Gould, J. P.; Haas, C. N.

    1978-01-01

    Presents a literature review of wastewater disinfection for 1978. This review covers areas such as: (1) mechanisms of inactivation of negative microorganisms by chlorine and ozone; and (2) the effects of various treatment on over-all water quality. A list of 61 references is also presented. (HM)

  12. Integrated Chemical and Toxicological Investigation of UV-Chlorine/Chloramine Drinking Water Treatment

    EPA Science Inventory

    As the use of alternative drinking water treatment increases, it is important to understand potential public health•implications associated with these processes. The objective of this study was to evaluate the formation of disinfection byproducts (DBPs) and cytotoxicity of ...

  13. Comprehensive Assessment of a Chlorinated Drinking Water Concentrate in a Rat Multigenerational Reproductive Toxicity Study##

    EPA Science Inventory

    Some epidemiological studies report associations between drinking water disinfection by-products (DBPs) and adverse reproductive and developmental effects, e.g., low birth weight, spontaneous abortion, stillbirth, and birth defects. To address concerns raised by these studies, w...

  14. Comprehensive assessment of a chlorinated drinking water concentrate in a rat multigenerational reproductive toxicity study

    EPA Science Inventory

    Some epidemiological studies report associations between drinking water disinfection by-products (DBPs) and adverse reproductive and developmental effects, e.g., low birth weight, spontaneous abortion, stillbirth, and birth defects. To address concerns raised by these studies, w...

  15. CONTROL OF MICROBES AND DBPS IN DRINKING WATER: AN OVERVIEW

    EPA Science Inventory

    Historically drinking water utilities in the United States (U.S.) have played a major role in protecting public health through the reduction of waterborne disease. These reductions in waterborne disease outbreaks were brought about by the use of sand filtration, disinfection and...

  16. NEUROTOXICITY PRODUCED BY DIBROMOACETIC ACID IN DRINKING WATER OF RATS.

    EPA Science Inventory

    This manuscript examines the neurotoxic potential of a commonly found disinfection by-product (DBP), dibromoacetic acid (DBA). While the Safe Drinking Water Act requires evaluation of DBPs for noncancer health effects, surprisingly few have been tested for neurotoxicity. Rats e...

  17. REMOVING ESOTERIC CONTAMINANTS FROM DRINKING WATERS: IMPACTS OF TREATMENT IMPLEMENTATION

    EPA Science Inventory

    At first blush, the production and distribution of drinking water seems to be a very straight forward process. There is a need to remove microbial agents and any anthropogenic or autochthonous contaminants that may be of health concern. Finally, a disinfectant is usually added to...

  18. Regenerable Iodine Water-Disinfection System

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

    1994-01-01

    Iodinated resin bed for disinfecting water regenerated to extend useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle manually controlled readily automated to start and stop according to signals from concentration sensors. Further benefit of regeneration is bed provides highly concentrated biocide source when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

  19. Comparative Mammalian cell cytotoxicity of water concentrates from disinfected recreational pools.

    PubMed

    Plewa, Michael J; Wagner, Elizabeth D; Mitch, William A

    2011-05-01

    Disinfection of recreational pools is essential to prevent outbreaks of infectious disease. Despite the health benefits of swimming, recent research demonstrated an association between the application of disinfectants to recreational pools and adverse health outcomes. Pool waters are extreme cases of disinfection that differ in important respects from disinfected drinking waters. Pool waters are continuously exposed to disinfectants over average residence times extending to months. Disinfection byproduct (DBP) precursors in pools include natural humic substances deriving from the tap water source plus inputs from bathers through urine, sweat, hair, skin, and consumer products including sunscreens and cosmetics. This study presents a systematic, chronic in vitro mammalian cell cytotoxicity analysis of different recreational waters with varied environmental conditions that were derived from a common tap water source. Recreational waters were significantly more toxic than their tap water source. Because trihalomethane concentrations are similar between tap waters and pool waters, using trihalomethanes to monitor exposure in epidemiological studies may not be the best metric. Of primary importance for cytotoxicity were illumination conditions. Pools subjected to a combination of ultraviolet light and free chlorine disinfection indoors, or outdoor sunlight exposure exhibited lower cytotoxicity than their indoor counterparts disinfected with free chlorine. Temperature and total organic carbon content, as an indirect measure of DBP precursors, were less important. Previous research on the same samples demonstrated the genotoxicity of an indoor pool disinfected with bromochlorodimethylhydantoin; the cytotoxicity of this sample was confirmed in the present study. While the association of reduced toxicity with illumination indicates that the agents responsible are photolabile, their identity is unclear. As a broad measure of adverse biological responses, cytotoxicity may be

  20. The Application of Physiologically Based Pharmacokinetic Modeling to Determine Route-Specific Contributions to Tissue Dosimetry of Trihalomethanes in Drinking Water

    EPA Science Inventory

    This project summary describes an improved approach for estimating route-specific exposures and tissue doses for trihalomethane (THM) compounds found in drinking water.

  1. Drinking-Water Standards and Regulations. Volume 2. Manual for 1982-88

    SciTech Connect

    Wang, L.K.; Wang, M.H.S.

    1988-04-10

    The following 11 important documents are compiled for Drinking Water Standards and Regulations: (1) U.S. Environmental Agency Water Programs, National Interim Primary Drinking Water Regulations; (2) New Jersey Safe Drinking Water Act; (3) Summary of New Jersey Drinking Water Standards; (4) U.S. Environmental Protection Agency Safe Drinking Water Act of 1986 Amendments; (5) U.S. Environmental Protection Agency National Primary Drinking Water Standards; (6) Canadian National Health and Welfare Drinking Water Quality Guidelines--Maximum Acceptable Concentrations; (7) U.S. Environmental Protection Agency, National Primary Drinking Water Regulations, Filtration and Disinfection Turbidity, Giardia Lamblia, Viruses, Legionella, and Heterotrophic Bacteria; (8) Public Water Supply Manual--Guide to the Safe Drinking Water Program; (9) Public Water Supply Manual--Emergency Response; (10) U.S. EPA Approved Krofta Chemicals; (11) NY-DOH Approved Krofta Chemicals.

  2. Drinking water and women's health.

    PubMed

    Afzal, Brenda M

    2006-01-01

    Primary health providers in the community must be able to field questions and guide vulnerable populations to informed decisions about drinking water quality and health. This article offers an overview of selected contaminants in drinking water and their possible effects on the health of women over the life span. Historical concerns for drinking water safety, which led to the development of current drinking water regulations, are briefly explored. Several chemical, microbial, and radionuclide contaminants of particular concern to women and children are discussed. Short- and long-term tap water alternatives are suggested for when tap water is deemed unsuitable for use.

  3. STUDIES ON WATER DRINKING

    PubMed Central

    Fowler, C. C.; Hawk, P. B.

    1910-01-01

    The daily drinking of three liters of water with meals, for a period of five days, by a man twenty-two years of age who was in a condition of nitrogen equilibrium through the ingestion of a uniform diet, was productive of the following findings : 1. An increase in body weight, aggregating two pounds in five days. 2. An increased excretion of urinary nitrogen, the excess nitrogen being mainly in the form of urea, ammonia, and creatine. 3. A decreased excretion of creatinine and the coincident appearance of creatine in the urine. The decreased creatinine output is believed to indicate that the copious water drinking has stimulated protein catabolism. The appearance of creatine is considered evidence that the water has caused a partial muscular disintegration resulting in the release of creatine, but not profound enough to yield the total nitrogen content of the muscle. The output of creatine is, therefore, out of all proportion to the increase in the excretion of total nitrogen. 4. An increased output of ammonia which is interpreted as indicating an increased output of gastric juice. 5. A decreased excretion of feces and of fecal nitrogen, the decrease in the excretion of fecal nitrogen being of sufficient magnitude to secure a lowered excretion of both the bacterial and the non-bacterial nitrogen. 6. A decrease in the quantity of bacteria excreted daily. 7. An increase in the percentage of total nitrogen appearing as bacterial nitrogen. 8. A lower creatinine coefficient. 9. A more economical utilization of the protein constituents of the diet. 10. The general conclusion to be reached as the result of this experiment is to the effect that the drinking of a large amount of water with meals was attended by many desirable and by no undesirable features. PMID:19867334

  4. What's next after 40 years of drinking water regulations?

    PubMed

    Roberson, J Alan

    2011-01-01

    The quality of drinking water in the United States has continued to improve over the past 40 years. The formation of the U.S. Environmental Protection Agency (USEPA) in 1971, the passage of the initial Safe Drinking Water Act (SDWA, PL 93-523) in 1974, and the passage of the 1996 SDWA Amendments (PL 104-208) represent significant progress in drinking water quality. While the widespread adoption of filtration and disinfection in the early 1900s virtually eliminated waterborne typhoid fever, some residual risks still remained 40 years ago. These national regulatory developments compelled USEPA and the drinking water community to address these remaining risks in drinking water and optimize risk reduction for the public.

  5. What's next after 40 years of drinking water regulations?

    PubMed

    Roberson, J Alan

    2011-01-01

    The quality of drinking water in the United States has continued to improve over the past 40 years. The formation of the U.S. Environmental Protection Agency (USEPA) in 1971, the passage of the initial Safe Drinking Water Act (SDWA, PL 93-523) in 1974, and the passage of the 1996 SDWA Amendments (PL 104-208) represent significant progress in drinking water quality. While the widespread adoption of filtration and disinfection in the early 1900s virtually eliminated waterborne typhoid fever, some residual risks still remained 40 years ago. These national regulatory developments compelled USEPA and the drinking water community to address these remaining risks in drinking water and optimize risk reduction for the public. PMID:21141882

  6. Nontargeted identification of peptides and disinfection byproducts in water.

    PubMed

    Tang, Yanan; Xu, Ying; Li, Feng; Jmaiff, Lindsay; Hrudey, Steve E; Li, Xing-Fang

    2016-04-01

    A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts (DBPs). Epidemiological findings of an association of increased risk of bladder cancer with the consumption of chlorinated water has resulted in health concerns about DBPs. Peptides are thought to be an important category of DBP precursors in water. However, little is known about the actual presence of peptides and their DBPs in drinking water because of their high sample complexity and low concentrations. To address this challenge and identify peptides and non-chlorinated/chlorinated peptide DBPs from large sets of organic compounds in water, we developed a novel high throughput analysis strategy, which integrated multiple solid phase extraction (SPE), high performance liquid chromatography (HPLC) separation, and non-target identification using precursor ion exclusion (PIE) high resolution mass spectrometry (MS). After MS analysis, structures of candidate compounds, particularly peptides, were obtained by searching against the Human Metabolome Database (HMDB). Using this strategy, we successfully detected 625 peptides (out of 17,205 putative compounds) and 617 peptides (out of 13,297) respectively in source and finished water samples. The source and finished water samples had 501 peptides and amino acids in common. The remaining 116 peptides and amino acids were unique to the finished water. From a subset of 30 putative compounds for which standards were available, 25 were confirmed using HPLC-MS analysis. By analyzing the peptides identified in source and finished water, we successfully confirmed three disinfection reaction pathways that convert peptides into toxic DBPs. PMID:27090718

  7. DETERMINATION OF BROMATE IN DRINKING WATERS BY ION CHROMATOGRAPHY WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC DETECTION

    EPA Science Inventory

    Bromate is a disinfection by-product in drinking water, formed during the ozonation of source water containing bromide. An inductively coupled plasma mass spectrometer is combined with an ion chromatograph for the analysis of bromate in drinking waters. Three chromatographic colu...

  8. The Effect of Oxidant and Redox Potential on Metal Corrosion in Drinking Water

    EPA Science Inventory

    Future drinking water regulatory action may require some water utilities to consider additional and/or alternative oxidation and disinfection practices. There is little known about the effect of oxidant changes on the corrosion of drinking water distribution system materials and ...

  9. OPTIMAL SCHEDULING OF BOOSTER DISINFECTION IN WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Booster disinfection is the addition of disinfectant at locations distributed throughout a water distribution system. Such a strategy can reduce the mass of disinfectant required to maintain a detectable residual at points of consumption in the distribution system, which may lea...

  10. Infectious Disinfection: "Exploring Global Water Quality"

    ERIC Educational Resources Information Center

    Mahaya, Evans; Tippins, Deborah J.; Mueller, Michael P.; Thomson, Norman

    2009-01-01

    Learning about the water situation in other regions of the world and the devastating effects of floods on drinking water helps students study science while learning about global water quality. This article provides science activities focused on developing cultural awareness and understanding how local water resources are integrally linked to the…

  11. RECOVERY OF MUTAGENICITY FROM DISINFECTED WATER SAMPLES BY XAD RESIN ADSORPTION COMPARED TO REVERSE OSMOSIS

    EPA Science Inventory

    the presence of a complex misture of disinfection byproducts in drinking waters continues to cause concern over the potential long-term health effects of exposure to these compounds. Most of these compounds are present at ug/L levels or less. Consequently, some method of concentr...

  12. REPRODUCTIVE AND GENOMIC EFFECTS IN TESTES FROM MICE EXPOSED TO THE WATER DISINFECTANT BYPRODUCT BROMOCHLOROACETIC ACID

    EPA Science Inventory

    ABSTRACT

    A byproduct of drinking water disinfection, bromochloroacetic acid (BCA), acts as a reproductive toxicant in rats. To determine if BCA produces similar reproductive toxicity in mice, juvenile and adult C57BL/6 males were exposed to 0, 8, 24, 72 or 216 mg/kg of BC...

  13. Ensuring safer drinking water

    SciTech Connect

    Christensen, J. . Fluid Delivery and Electrical Markets); Higgins, P. )

    1994-09-01

    Today's regulatory environment has led to the proliferation of voluntary consensus standards and certification programs that are important to ensuring safety and health in a number of areas. One such area -- the treatment and delivery of potable water -- is addressed by the Drinking Water Additives Program.'' At the request of the Environmental Protection Agency (EPA), this program was developed in the mid-1980s by an independent, voluntary consensus standards organization called NSF International (formerly known as the National Sanitation Foundation). This paper explains the need for and the structure of the Drinking Water Additives Program; the rationale for transferring responsibility for its execution from the EPA to the private sector; and the impact of its standards on users, manufacturers, and state and local regulatory bodies. Understanding the additives program is critically important to industry suppliers because, as it continues to gain greater awareness and acceptance, there are a growing number of manufacturers sourcing materials and products primarily from suppliers whose products meet the program's certification requirements.

  14. Establishment and Early Succession of Bacterial Communities in Monochloramine-treated Drinking Water Biofilms

    EPA Science Inventory

    The use of monochloramine as drinking water disinfectant is increasing because it forms lower levels of traditional disinfection by-products compared to free-chlorine. However, little is known about the bacterial succession within biofilms in monochloramine-treated systems. The d...

  15. Establishment and Early Succession of Bacterial Communities in Monochloramine-Treated Drinking Water Biofilms

    EPA Science Inventory

    Monochloramine is increasingly used as a drinking water disinfectant because it forms lower levels of regulated disinfection by-products. While its use has been shown to increase nitrifying bacteria, little is known about the bacterial succession within biofilms in monochloramin...

  16. Safe and Affordable Drinking Water for Developing Countries

    NASA Astrophysics Data System (ADS)

    Gadgil, Ashok

    2008-09-01

    Safe drinking water remains inaccessible for about 1.2 billion people in the world, and the hourly toll from biological contamination of drinking water is 200 deaths mostly among children under five years of age. This chapter summarizes the need for safe drinking water, the scale of the global problem, and various methods tried to address it. Then it gives the history and current status of an innovation ("UV Waterworks™") developed to address this major public health challenge. It reviews water disinfection technologies applicable to achieve the desired quality of drinking water in developing countries, and specifically, the limitations overcome by one particular invention: UV Waterworks. It then briefly describes the business model and financing option than is accelerating its implementation for affordable access to safe drinking water to the unserved populations in these countries. Thus this chapter describes not only the innovation in design of a UV water disinfection system, but also innovation in the delivery model for safe drinking water, with potential for long term growth and sustainability.

  17. Water Quality Modeling in the Dead End Sections of Drinking Water Distribution Networks -journal article

    EPA Science Inventory

    Dead-end sections of drinking water distribution networks are known to be problematic zones in terms of water quality degradation. Extended residence time due to water stagnation leads to rapid reduction of disinfectant residuals allowing the regrowth of microbial pathogens. Wate...

  18. Water Quality Modeling in the Dead End Sections of Drinking Water Distribution Networks

    EPA Science Inventory

    Dead-end sections of drinking water distribution networks are known to be problematic zones in terms of water quality degradation. Extended residence time due to water stagnation leads to rapid reduction of disinfectant residuals allowing the regrowth of microbial pathogens. Wate...

  19. DISINFECTION BYPRODUCTS: THE NEXT GENERATION

    EPA Science Inventory

    Disinfection of drinking water is rightly hailed as a major public health triumph of the 20th Century. Before widespread disinfection of drinking water in the U.S. and Europe, millions of people died from infectious waterborne diseases, such as typhoid and cholera. The microbia...

  20. Emerging nitrogenous disinfection byproducts: Transformation of the antidiabetic drug metformin during chlorine disinfection of water.

    PubMed

    Armbruster, Dominic; Happel, Oliver; Scheurer, Marco; Harms, Klaus; Schmidt, Torsten C; Brauch, Heinz-Jürgen

    2015-08-01

    As an environmental contaminant of anthropogenic origin metformin is present in the high ng/L- up to the low μg/L-range in most surface waters. Residues of metformin may lead to the formation of disinfection by-products during chlorine disinfection, when these waters are used for drinking water production. Investigations on the underlying chemical processes occurring during treatment of metformin with sodium hypochlorite in aqueous medium led to the discovery of two hitherto unknown transformation products. Both substances were isolated and characterized by HPLC-DAD, GC-MS, HPLC-ESI-TOF, (1)H-NMR and single-crystal X-ray structure determination. The immediate major chlorination product is a cyclic dehydro-1,2,4-triazole-derivate of intense yellow color (Y; C4H6ClN5). It is a solid chlorimine of limited stability. Rapid formation was observed between 10 °C and 30 °C, as well as between pH 3 and pH 11, in both ultrapure and tap water, even at trace quantities of reactants (ng/L-range for metformin, mg/L-range for free chlorine). While Y is degraded within a few hours to days in the presence of light, elevated temperature, organic solvents and matrix constituents within tap water, a secondary degradation product was discovered, which is stable and colorless (C; C4H6ClN3). This chloroorganic nitrile has a low photolysis rate in ambient day light, while being resistant to heat and not readily degraded in the presence of organic solvents or in the tap water matrix. In addition, the formation of ammonia, dimethylamine and N,N-dimethylguanidine was verified by cation exchange chromatography.

  1. Handbook of ozone technology and applications. Vol. 2. Ozone for drinking water treatment

    SciTech Connect

    Rice, R.G.; Netzer, A.

    1984-01-01

    This volume of the handbook series concerns the application of ozone for the treatment of drinking water. Great emphasis is given ozone's powerful disinfectant and oxidant properties with the added advantage of the non-production of undesirable by-products. European sources have been heavily drawn upon since that is where most of the experience has been. Over one-third of the volume is devoted to a bibliography of some 1600 citations (in addition to 260 as chapter references). Contents: Ozone disinfection of drinking water. Removal of color from drinking water with ozone. Removal of ammonia and other nitrogen derivatives from drinking water with ozone. Raw water preozonation. Recent developments in the treatment of drinking water. Ozone for drinking water treatment - a bibliography. Index.

  2. Research Issues Underlying the Four-Lab Study: Integrated Disinfection Byproducts Mixtures Research

    EPA Science Inventory

    Chemical disinfection of drinking water is a major public health triumph of the 20th century, resulting in significant decreases in morbidity and mortality from waterborne diseases. Disinfection byproducts (DBPs) are chemicals formed by the reaction of oxidizing disinfectants wi...

  3. Flocculant-disinfectant point-of-use water treatment for reducing arsenic exposure in rural Bangladesh.

    PubMed

    Norton, Dawn M; Rahman, Mahfuz; Shane, Andi L; Hossain, Zahid; Kulick, Roy M; Bhuiyan, Mahbubul I; Wahed, M Abdul; Yunus, Mohammad; Islam, M Siraj; Breiman, Robert F; Henderson, Alden; Keswick, Bruce H; Luby, Stephen P

    2009-02-01

    We introduced flocculant-disinfectant water treatment for 12 weeks in 103 households in Bangladesh to assess if drinking water would be chemically and microbiologically improved and the body burden of arsenic reduced. The median concentration of arsenic in tubewell water decreased by 88% after introduction of the flocculant-disinfectant from 136 microg/l at baseline to 16 (p < 0.001). The median concentration of total urinary arsenic decreased 42% from 385 microg/g creatinine at baseline to 225 microg/g creatinine after intervention (p < 0.001). Among 206 post-intervention drinking water samples that were reportedly treated on the date the sample was collected, 99 (48%) lacked residual free chlorine and 100 (49%) were contaminated with thermotolerant coliforms. The flocculant-disinfectant markedly reduced arsenic in drinking water, but treated drinking water was frequently contaminated with fecal organisms. The lesser reduction in urinary arsenic compared to water arsenic and the health consequences of this reduction require further research. PMID:19241244

  4. Flocculant-disinfectant point-of-use water treatment for reducing arsenic exposure in rural Bangladesh.

    PubMed

    Norton, Dawn M; Rahman, Mahfuz; Shane, Andi L; Hossain, Zahid; Kulick, Roy M; Bhuiyan, Mahbubul I; Wahed, M Abdul; Yunus, Mohammad; Islam, M Siraj; Breiman, Robert F; Henderson, Alden; Keswick, Bruce H; Luby, Stephen P

    2009-02-01

    We introduced flocculant-disinfectant water treatment for 12 weeks in 103 households in Bangladesh to assess if drinking water would be chemically and microbiologically improved and the body burden of arsenic reduced. The median concentration of arsenic in tubewell water decreased by 88% after introduction of the flocculant-disinfectant from 136 microg/l at baseline to 16 (p < 0.001). The median concentration of total urinary arsenic decreased 42% from 385 microg/g creatinine at baseline to 225 microg/g creatinine after intervention (p < 0.001). Among 206 post-intervention drinking water samples that were reportedly treated on the date the sample was collected, 99 (48%) lacked residual free chlorine and 100 (49%) were contaminated with thermotolerant coliforms. The flocculant-disinfectant markedly reduced arsenic in drinking water, but treated drinking water was frequently contaminated with fecal organisms. The lesser reduction in urinary arsenic compared to water arsenic and the health consequences of this reduction require further research.

  5. Regenerable Iodine Water-Disinfection System

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

    1994-01-01

    Iodinated resin bed for disinfecting water regenerated to extend its useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle was manually controlled in demonstration, readily automated to start and stop according to signals and stop according to signals from concentration sensors. Further benefit of regeneration is that regeneration bed provides highly concentrated biocide source (200 mg/L) when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

  6. EVALUATION OF THE CYTOTOXICITY OF DRINKING WATER DISINFECTION BYPRODUCTS (DBPS): TRIHALOMETHANES (THMS), HALONITROMETHANES (HNMS), AND HALOACETIC ACIDS (HAAS) IN NORMAL HUMAN COLON CELLS

    EPA Science Inventory

    Epidemiological studies have linked the consumption of chlorinated surface waters to an increased risk of colorectal cancer. THMs and HAAs were found to increase cancer in laboratory animals, but no toxicity studies exist for the recently identified HNMs. Normal Human colonocytes...

  7. Concentration, Chlorination, and Chemical Analysis of Drinking Water for Disinfection Byproduct Mixtures Health Effects Research: U.S. EPA’s Four Lab Study

    EPA Science Inventory

    The U.S. Environmental Protection Agency’s ‘Four Lab Study’, involved participation of scientists and engineers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from water industry and academia. The study evaluated tox...

  8. Concentration, Chlorination, and Chemical Analysis of Drinking Water for Disinfection Byproduct Mixtures Health Effects Research: U.S. EPA’s Four Lab Study

    EPA Science Inventory

    The U.S. Environmental Protection Agency’s “Four Lab Study” involved participation of researchers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from the water industry and academia. The study evaluated toxicological...

  9. Lead in School Drinking Water.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Water Programs.

    Lead levels in school drinking water merit special concern because children are more at risk than adults from exposure to lead. This manual provides ways in which school officials can minimize this risk. It assists administrators by providing: (1) general information on the significance of lead in school drinking water and its effects on children;…

  10. Drinking Water Treatability Database (Database)

    EPA Science Inventory

    The drinking Water Treatability Database (TDB) will provide data taken from the literature on the control of contaminants in drinking water, and will be housed on an interactive, publicly-available USEPA web site. It can be used for identifying effective treatment processes, rec...

  11. Drinking water microbiology--new directions toward water quality enhancement.

    PubMed

    Geldreich, E E

    1989-12-01

    Drinking water microbiology has emerged from decades of relative complacency to recognize there can be major concerns with potable water quality. Many of these issues are a result of an explosion of information on new waterborne agents, treatment problems with raw-source water qualities, biofilm development in some distribution systems and specialized requirements in water quality unique to hospitals and industries. Protozoan cyst survival after some disinfection practices involving surface water impoundments and virus occurrence in poorly protected groundwaters have provided reasons for expanding minimum treatment of surface waters and for requiring disinfection of all groundwaters unless there is a demonstrative data base to support exceptions in treatment requirements. Official monitoring of small water supplies must be increased on a monthly basis and a rapid alert established to inform water plant operators of unsatisfactory water qualities. As an option, application of operational tests to analyse water quality in terms of chlorine residual, turbidity, total coliforms and heterotrophic bacterial counts in small water plant operations should be encouraged. This would provide the operator at remote locations with the opportunity to utilize the information to make necessary treatment adjustments or corrections in water distribution deficiencies promptly and be a supplement to the official regional monitoring program. Application of drinking water alternative sources (bottled water and water from point-of-use treatment devices) should be viewed by the health authorities as only a temporary solution, not as a permanent fix for a public water supply known to present some established health risk to consumers. The public must also recognize that bottled water is not frequently monitored by health laboratories for acceptable quality and the use of home treatment devices places the responsibility of proper maintenance on the user. Microbial quality improvements in

  12. Safe drinking water: a public health challenge.

    PubMed

    Wigle, D T

    1998-01-01

    Disinfection of drinking water through processes including filtration and chlorination was one of the major achievements of public health, beginning in the late 1800s and the early 1900s. Chloroform and other chlorination disinfection by-products (CBPs) in drinking water were first reported in 1974. Chloroform and several other CBPs are known to cause cancer in experimental animals, and there is growing epidemiologic evidence of a causal role for CBPs in human cancer, particularly for bladder cancer. It has been estimated that 14 16% of bladder cancers in Ontario may be attributable to drinking water containing relatively high levels of CBPs; the US Environmental Protection Agency has estimated the attributable risk to be 2 17%. These estimates are based on the assumption that the associations observed between bladder cancer and CBP exposure reflect a cause-effect relation. An expert working group (see Workshop Report in this issue) concluded that it was possible (60% of the group) to probable (40% of the group) that CBPs pose a significant cancer risk, particularly of bladder cancer. The group concluded that the risk of bladder and possibly other types of cancer is a moderately important public health problem. There is an urgent need to resolve this and to consider actions based on the body of evidence which, at a minimum, suggests that lowering of CBP levels would prevent a significant fraction of bladder cancers. In fact, given the widespread and prolonged exposure to CBPs and the epidemiologic evidence of associations with several cancer sites, future research may establish CBPs as the most important environmental carcinogens in terms of the number of attributable cancers per year.

  13. Drinking Water Database

    NASA Technical Reports Server (NTRS)

    Murray, ShaTerea R.

    2004-01-01

    This summer I had the opportunity to work in the Environmental Management Office (EMO) under the Chemical Sampling and Analysis Team or CS&AT. This team s mission is to support Glenn Research Center (GRC) and EM0 by providing chemical sampling and analysis services and expert consulting. Services include sampling and chemical analysis of water, soil, fbels, oils, paint, insulation materials, etc. One of this team s major projects is the Drinking Water Project. This is a project that is done on Glenn s water coolers and ten percent of its sink every two years. For the past two summers an intern had been putting together a database for this team to record the test they had perform. She had successfully created a database but hadn't worked out all the quirks. So this summer William Wilder (an intern from Cleveland State University) and I worked together to perfect her database. We began be finding out exactly what every member of the team thought about the database and what they would change if any. After collecting this data we both had to take some courses in Microsoft Access in order to fix the problems. Next we began looking at what exactly how the database worked from the outside inward. Then we began trying to change the database but we quickly found out that this would be virtually impossible.

  14. Drowning in disinfection byproducts? Assessing swimming pool water.

    PubMed

    Zwiener, Christian; Richardson, Susan D; DeMarini, David M; De Marini, David M; Grummt, Tamara; Glauner, Thomas; Frimmel, Fritz H

    2007-01-15

    Disinfection is mandatory for swimming pools: public pools are usually disinfected by gaseous chlorine or sodium hypochlorite and cartridge filters; home pools typically use stabilized chlorine. These methods produce a variety of disinfection byproducts (DBPs), such as trihalomethanes (THMs), which are regulated carcinogenic DBPs in drinking water that have been detected in the blood and breath of swimmers and of nonswimmers at indoor pools. Also produced are halogenated acetic acids (HAAs) and haloketones, which irritate the eyes, skin, and mucous membranes; trichloramine, which is linked with swimming-pool-associated asthma; and halogenated derivatives of UV sun screens, some of which show endocrine effects. Precursors of DBPs include human body substances, chemicals used in cosmetics and sun screens, and natural organic matter. Analytical research has focused also on the identification of an additional portion of unknown DBPs using gas chromatography (GC)/mass spectrometry (MS) and liquid chromatography (LC)/MS/MS with derivatization. Children swimmers have an increased risk of developing asthma and infections of the respiratory tract and ear. A 1.6-2.0-fold increased risk for bladder cancer has been associated with swimming or showering/bathing with chlorinated water. Bladder cancer risk from THM exposure (all routes combined) was greatest among those with the GSTT1-1 gene. This suggests a mechanism involving distribution of THMs to the bladder by dermal/inhalation exposure and activation there by GSTT1-1 to mutagens. DBPs may be reduced by engineering and behavioral means, such as applying new oxidation and filtration methods, reducing bromide and iodide in the source water, increasing air circulation in indoor pools, and assuring the cleanliness of swimmers. The positive health effects gained by swimming can be increased by reducing the potential adverse health risks. PMID:17310693

  15. Disinfection of contaminated water by using solar irradiation.

    PubMed

    Caslake, Laurie F; Connolly, Daniel J; Menon, Vilas; Duncanson, Catriona M; Rojas, Ricardo; Tavakoli, Javad

    2004-02-01

    Contaminated water causes an estimated 6 to 60 billion cases of gastrointestinal illness annually. The majority of these cases occur in rural areas of developing nations where the water supply remains polluted and adequate sanitation is unavailable. A portable, low-cost, and low-maintenance solar unit to disinfect unpotable water has been designed and tested. The solar disinfection unit was tested with both river water and partially processed water from two wastewater treatment plants. In less than 30 min in midday sunlight, the unit eradicated more than 4 log10 U (99.99%) of bacteria contained in highly contaminated water samples. The solar disinfection unit has been field tested by Centro Panamericano de Ingenieria Sanitaria y Ciencias del Ambiente in Lima, Peru. At moderate light intensity, the solar disinfection unit was capable of reducing the bacterial load in a controlled contaminated water sample by 4 log10 U and disinfected approximately 1 liter of water in 30 min.

  16. Environmental and urinary markers of prenatal exposure to drinking water disinfection by-products, fetal growth, and duration of gestation in the PELAGIE birth cohort (Brittany, France, 2002-2006).

    PubMed

    Costet, Nathalie; Garlantézec, Ronan; Monfort, Christine; Rouget, Florence; Gagnière, Bertrand; Chevrier, Cécile; Cordier, Sylvaine

    2012-02-15

    Although prenatal exposure to water disinfection by-products does not appear to affect the duration of gestation, its impact on fetal growth remains an open question. The authors studied the associations between prenatal exposure to disinfection by-products and fetal growth restriction (FGR) and preterm birth in the PELAGIE cohort, a French birth cohort comprising 3,421 pregnant women recruited between 2002 and 2006. Exposure was assessed by estimating levels of trihalomethanes (THMs) in tap water during pregnancy and maternal water use and by measuring maternal urinary levels of trichloroacetic acid (TCAA) during early pregnancy in a nested case-control design that compared 174 FGR cases, 114 preterm births, and 399 controls. Higher uptake of THMs (especially brominated THMs) was associated with a higher risk of FGR. Women with TCAA detected in their urine (>0.01 mg/L) had a higher risk of FGR than those with TCAA levels below the detection limit (adjusted odds ratio = 1.8, 95% confidence interval: 0.9, 3.7) and had an odds ratio for preterm birth below 1 (adjusted odds ratio = 0.8, 95% confidence interval: 0.3, 2.6). Results from this prospective study, the first to use a biomarker of disinfection by-product exposure, suggest that prenatal exposure affects fetal growth, but the causal agent or agents remain to be identified.

  17. Exploring the potential of magnetic antimicrobial agents for water disinfection.

    PubMed

    Pina, Ana S; Batalha, Iris L; Fernandes, Cláudia S M; Aoki, Matheus A; Roque, Ana C A

    2014-12-01

    Industrial and urban activities yield large amounts of contaminated groundwater, which present a major health issue worldwide. Infectious diseases are the most common health risk associated with drinking-water and wastewater remediation is a major concern of our modern society. The field of wastewater treatment is being revolutionized by new nano-scale water disinfection devices which outperform most currently available technologies. In particular, iron oxide magnetic nanoparticles (MNPs) have been widely used in environmental applications due to their unique physical-chemical properties. In this work, poly(ethylene) glycol (PEG)-coated MNPs have been functionalized with (RW)3, an antimicrobial peptide, to yield a novel magnetic-responsive support with antimicrobial activity against Escherichia coli K-12 DSM498 and Bacillus subtilis 168. The magnetic-responsive antimicrobial device showed to be able to successfully disinfect the surrounding solution. Using a rapid high-throughput screening platform, the minimal inhibitory concentration (MIC) was determined to be 500 μM for both strains with a visible bactericidal effect.

  18. A practical demonstration of water disinfection using TiO2 films and sunlight.

    PubMed

    Gelover, Silvia; Gómez, Luis A; Reyes, Karina; Teresa Leal, Ma

    2006-10-01

    The scope of this study is the assessment of the efficiency of solar disinfection by heterogeneous photocatalysis with sol-gel immobilized (titanium dioxide) TiO2 films over glass cylinders. The solar disinfection process known as SODIS was considered as a reference. Spring water naturally polluted with coliform bacteria was exposed to sunlight in plastic bottles with and without TiO2 over simple solar collectors and the disinfection effectiveness was measured. Total and fecal coliforms quantification was performed by means of the chromogenic substrate method in order to obtain the efficiency of each disinfection treatment. The disinfection with TiO2 was more efficient than the SODIS process, inactivating total coliforms as well as fecal coliforms. On a sunny day (more than 1000 W m(-2) irradiance), it took the disinfection with immobilized TiO2 15 min of irradiation to inactivate the fecal coliforms to make them undetectable. For inactivation of total coliforms, 30 min was required, so that in less than half the time it takes SODIS, the treated water complies with the microbial standards for drinking water in Mexico. Another important part of this study has been to determine the bacterial regrowth in water after the disinfection processes were tested. After SODIS, bacterial regrowth of coliforms was observed. In contrast, when using the TiO2 catalyst, coliforms regrowth was not detected, neither for total nor for fecal coliforms. The disinfection process using TiO2 kept treated water free of coliforms at least for seven days after sun irradiation. This demonstration opens the possibility of application of this simple method in rural areas of developing countries.

  19. Factors from the transtheoretical model differentiating between solar water disinfection (SODIS) user groups.

    PubMed

    Kraemer, Silvie M; Mosler, Hans-Joachim

    2011-01-01

    Solar water disinfection (SODIS) is a sustainable household water treatment technique that could prevent millions of deaths caused by diarrhoea. The behaviour change process necessary to move from drinking raw water to drinking SODIS is analysed with the Transtheoretical Model of Change (TTM). User groups and psychological factors that differentiate between types of users are identified. Results of a 1.5 year longitudinal study in Zimbabwe reveal distinguishing factors between groups, from which it can be deduced that they drive the development of user groups. Implications are drawn for campaigns with the aim of bringing all user types to a regular use.

  20. MODULATION OF THE CYTOTOXICITY AND GENOTOXICITY OF THE DRINKING WATER DBP IODOACETIC ACID BY SUPPRESSORS OF OXIDATIVE STRESS

    EPA Science Inventory

    Drinking water disinfection by-products (DBPs) are generated by the chemical disinfection of water and may pose a hazard to the public health. Previously we demonstrated that iodoacetic acid was the most cytotoxic and genotoxic DBP analyzed in a mammalian cell system. Little is k...

  1. IMMUNOTOXICITY OF DlBROMOACETIC ACID ADMINISTERED VIA DRINKING WATER TO FEMALE B6C3Fl MICE

    EPA Science Inventory

    Dibromoacetic acid (DBA) is a disinfection by product commonly found in drinking water as a result of chlorination/ozonation processes. The EPA estimates that more than 200 million people consume disinfected water in the U.S. (EPA 1998). This study was conducted to evaluate the p...

  2. IDENTIFICATION OF DISINFECTION BY-PRODUCTS IN SWIMMING POOL WATER

    EPA Science Inventory

    In order to kill harmful pathogens, swimming pool water is treated with a disinfectant, such as chlorine or ozone. One of the most commonly used disinfectants is stabilized chlorine (typically trichloro-S-triazinetrione). Trichloro-S-triazinetrione reacts in water to form one m...

  3. Calibrating an optimal condition model for solar water disinfection in peri-urban household water treatment in Kampala, Uganda.

    PubMed

    Okurut, Kenan; Wozei, Eleanor; Kulabako, Robinah; Nabasirye, Lillian; Kinobe, Joel

    2013-03-01

    In low income settlements where the quality of drinking water is highly contaminated due to poor hygienic practices at community and household levels, there is need for appropriate, simple, affordable and environmentally sustainable household water treatment technology. Solar water disinfection (SODIS) that utilizes both the thermal and ultra-violet effect of solar radiation to disinfect water can be used to treat small quantities of water at household level to improve its bacteriological quality for drinking purposes. This study investigated the efficacy of the SODIS treatment method in Uganda and determined the optimal condition for effective disinfection. Results of raw water samples from the study area showed deterioration in bacteriological quality of water moved from source to the household; from 3 to 36 cfu/100 mL for tap water and 75 to 126 cfu/100 mL for spring water, using thermotolerant coliforms (TTCs) as indicator microorganisms. SODIS experiments showed over 99.9% inactivation of TTCs in 6 h of exposure, with a threshold temperature of 39.5 ± 0.7°C at about 12:00 noon, in the sun during a clear sunny day. A mathematical optimal condition model for effective disinfection has been calibrated to predict the decline of the number of viable microorganisms over time. PMID:23428553

  4. Calibrating an optimal condition model for solar water disinfection in peri-urban household water treatment in Kampala, Uganda.

    PubMed

    Okurut, Kenan; Wozei, Eleanor; Kulabako, Robinah; Nabasirye, Lillian; Kinobe, Joel

    2013-03-01

    In low income settlements where the quality of drinking water is highly contaminated due to poor hygienic practices at community and household levels, there is need for appropriate, simple, affordable and environmentally sustainable household water treatment technology. Solar water disinfection (SODIS) that utilizes both the thermal and ultra-violet effect of solar radiation to disinfect water can be used to treat small quantities of water at household level to improve its bacteriological quality for drinking purposes. This study investigated the efficacy of the SODIS treatment method in Uganda and determined the optimal condition for effective disinfection. Results of raw water samples from the study area showed deterioration in bacteriological quality of water moved from source to the household; from 3 to 36 cfu/100 mL for tap water and 75 to 126 cfu/100 mL for spring water, using thermotolerant coliforms (TTCs) as indicator microorganisms. SODIS experiments showed over 99.9% inactivation of TTCs in 6 h of exposure, with a threshold temperature of 39.5 ± 0.7°C at about 12:00 noon, in the sun during a clear sunny day. A mathematical optimal condition model for effective disinfection has been calibrated to predict the decline of the number of viable microorganisms over time.

  5. Enhanced drinking water supply through harvested rainwater treatment

    NASA Astrophysics Data System (ADS)

    Naddeo, Vincenzo; Scannapieco, Davide; Belgiorno, Vincenzo

    2013-08-01

    Decentralized drinking water systems represent an important element in the process of achieving the Millennium Development Goals, as centralized systems are often inefficient or nonexistent in developing countries. In those countries, most water quality related problems are due to hygiene factors and pathogens. A potential solution might include decentralized systems, which might rely on thermal and/or UV disinfection methods as well as physical and chemical treatments to provide drinking water from rainwater. For application in developing countries, decentralized systems major constraints include low cost, ease of use, environmental sustainability, reduced maintenance and independence from energy sources. This work focuses on an innovative decentralized system that can be used to collect and treat rainwater for potable use (drinking and cooking purposes) of a single household, or a small community. The experimented treatment system combines in one compact unit a Filtration process with an adsorption step on GAC and a UV disinfection phase in an innovative design (FAD - Filtration Adsorption Disinfection). All tests have been carried out using a full scale FAD treatment unit. The efficiency of FAD technology has been discussed in terms of pH, turbidity, COD, TOC, DOC, Escherichia coli and Total coliforms. FAD technology is attractive since it provides a total barrier for pathogens and organic contaminants, and reduces turbidity, thus increasing the overall quality of the water. The FAD unit costs are low, especially if compared to other water treatment technologies and could become a viable option for developing countries.

  6. A MULTIPLE-PURPOSE DESIGN APPROACH TO THE EVALUATION OF RISKS FROM COMPLEX MIXTURES OF DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Drinking water disinfection has effectively eliminated much of the morbidity and mortality associated with waterborne infectious diseases in the United States. Various disinfection processes, however, produce certain types and amounts of disinfection by-products (DBPs), including...

  7. Differences in dissolved organic matter between reclaimed water source and drinking water source.

    PubMed

    Hu, Hong-Ying; Du, Ye; Wu, Qian-Yuan; Zhao, Xin; Tang, Xin; Chen, Zhuo

    2016-05-01

    Dissolved organic matter (DOM) significantly affects the quality of reclaimed water and drinking water. Reclaimed water potable reuse is an effective way to augment drinking water source and de facto reuse exists worldwide. Hence, when reclaimed water source (namely secondary effluent) is blended with drinking water source, understanding the difference in DOM between drinking water source (dDOM) and reclaimed water source (rDOM) is essential. In this study, composition, transformation, and potential risk of dDOM from drinking water source and rDOM from secondary effluent were compared. Generally, the DOC concentration of rDOM and dissolved organic nitrogen (DON) content in reclaimed water source were higher but rDOM exhibited a lower aromaticity. Besides, rDOM comprises a higher proportion of hydrophilic fractions and more low-molecular weight compounds, which are difficult to be removed during coagulation. Although dDOM exhibited higher specific disinfection byproducts formation potential (SDBPFP), rDOM formed more total disinfection byproducts (DBPs) during chlorination including halomethanes (THMs) and haloacetic acids (HAAs) due to high DOC concentration. Likewise, in consideration of DOC basis, rDOM contained more absolute assimilable organic carbon (AOC) despite showing a lower specific AOC (normalized AOC per unit of DOC). Besides, rDOM exhibited higher biotoxicity including genotoxicity and endocrine disruption. Therefore, rDOM presents a greater potential risk than dDOM does. Reclaimed water source needs to be treated carefully when it is blended with drinking water source.

  8. Differences in dissolved organic matter between reclaimed water source and drinking water source.

    PubMed

    Hu, Hong-Ying; Du, Ye; Wu, Qian-Yuan; Zhao, Xin; Tang, Xin; Chen, Zhuo

    2016-05-01

    Dissolved organic matter (DOM) significantly affects the quality of reclaimed water and drinking water. Reclaimed water potable reuse is an effective way to augment drinking water source and de facto reuse exists worldwide. Hence, when reclaimed water source (namely secondary effluent) is blended with drinking water source, understanding the difference in DOM between drinking water source (dDOM) and reclaimed water source (rDOM) is essential. In this study, composition, transformation, and potential risk of dDOM from drinking water source and rDOM from secondary effluent were compared. Generally, the DOC concentration of rDOM and dissolved organic nitrogen (DON) content in reclaimed water source were higher but rDOM exhibited a lower aromaticity. Besides, rDOM comprises a higher proportion of hydrophilic fractions and more low-molecular weight compounds, which are difficult to be removed during coagulation. Although dDOM exhibited higher specific disinfection byproducts formation potential (SDBPFP), rDOM formed more total disinfection byproducts (DBPs) during chlorination including halomethanes (THMs) and haloacetic acids (HAAs) due to high DOC concentration. Likewise, in consideration of DOC basis, rDOM contained more absolute assimilable organic carbon (AOC) despite showing a lower specific AOC (normalized AOC per unit of DOC). Besides, rDOM exhibited higher biotoxicity including genotoxicity and endocrine disruption. Therefore, rDOM presents a greater potential risk than dDOM does. Reclaimed water source needs to be treated carefully when it is blended with drinking water source. PMID:26874770

  9. The risks of drinking water

    NASA Astrophysics Data System (ADS)

    Reichhardt, Tony

    1984-04-01

    Three researchers from the Energy and Environmental Policy Center at Harvard University have come up with a new method of calculating the risk from contaminants in drinking water, one that they believe takes into account some of the uncertainties in pronouncing water safe or dangerous to drink. The new method concentrates on the risk of cancer, which authors Edmund Crouch, Richard Wilson, and Lauren Zeise believe has not been properly considered in establishing drinking water standards.Writing in the December 1983 issue of Water Resources Research, the authors state that “current [drinking water] standards for a given chemical or class of chemicals do not account for the presence of other pollutants” that could combine to create dangerous substances. According to Wilson, “Over a hundred industrial pollutants and chlorination byproducts have been found in various samples of drinking water, some of which are known carcinogens, others suspected carcinogens.” The same chlorine that solves one major health problem—the threat of bacterial disease—can thus contribute to another, according to the authors, by increasing the long-term risk of cancer. The largest risks are due to halomethanes such as chloroform and bromoform, produced as chlorine reacts with organic matter in drinking water.

  10. Optimization of fixed titanium dioxide film on PET bottles and visual indicator for water disinfection

    NASA Astrophysics Data System (ADS)

    Heredia-Munoz, Manuel Antonio

    Water is perhaps the most important resource that sustains human life. According to the World Health Organization (WHO), almost two billion people do not have access to the required water that is needed to satisfy their daily needs and one billion do not have access to clean sources of water for consumption, most of them living in isolated and poor areas around the globe. Poor quality water increases the risk of cholera, typhoid fever and dysentery, and other water-borne illness making this problem a real crisis that humankind is facing. Several water disinfection technologies have been proposed as solutions for this problem. Solar water disinfection using TiO2 coated PET bottles was the alternative that is studied in this work. This technology does not only inactivate bacteria but also disintegrates organic chemicals that can be present in water. The objectives of this work address the optimization of the TiO 2 coated PET bottles technologies. The improvement on the bottle coating process, using two coats of 10% W/V of TiO2 in a solution of vinegar and sodium bicarbonate to form the TiO2 film, the use of a different indigo carmine (1.25 X 10-1mg/pill) concentration in the pill indicat