Innovative method for prioritizing emerging disinfection by-products (DBPs) in drinking water on the basis of their potential impact on public health.

Providing microbiologically safe drinking water is a major public health issue. However, chemical disinfection can produce unintended health hazards involving disinfection by-products (DBPs). In an attempt to clarify the potential public health concerns associated with emerging disinfection by-products (EDBPs), this study was intended to help to identify those suspected of posing potential related health effects. In view of the ever-growing list of EDBPs in drinking water and the lack of consensus about them, we have developed an innovative prioritization method that would allow us to address this issue. We first set up an exhaustive database including all the current published data relating to EDBPs in drinking water (toxicity, occurrence, epidemiology and international or local guidelines/regulations). We then developed a ranking method intended to prioritize the EDBPs. This method, which was based on a calculation matrix with different coefficients, was applied to the data regarding their potential contribution to the health risk assessment process. This procedure allowed us to identify and rank three different groups of EDBPs: Group I, consisting of the most critical EDBPs with regard to their potential health effects, has moderate occurrence but the highest toxicity. Group II has moderate to elevated occurrence and is associated with relevant toxicity, and Group III has very low occurrence and unknown or little toxicity. The EDBPs identified as posing the greatest potential risk using this method were as follows: NDMA and other nitrosamines, MX and other halofuranones, chlorate, formaldehyde and acetaldehyde, 2,4,6-trichlorophenol and pentachlorophenol, hydrazine, and two unregulated halomethanes, dichloromethane and tetrachloromethane. Our approach allowed us to define the EDBPs that it is most important to monitor in order to assess population exposure and related public health issues, and thus to improve drinking water treatment and distribution. It is also important to extend our knowledge about exposure to mixtures of emerging DBPs and possible related health effects.

[1]  M. Moyer,et al.  Development of normal human colon cell cultures to identify priority unregulated disinfection by-products with a carcinogenic potential. , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.

[2]  K. Cantor,et al.  Drinking water and cancer , 1997, Cancer Causes & Control.

[3]  T J Mason,et al.  Bladder cancer, drinking water source, and tap water consumption: a case-control study. , 1987, Journal of the National Cancer Institute.

[4]  D A Savitz,et al.  Drinking water and pregnancy outcome in central North Carolina: source, amount, and trihalomethane levels. , 1995, Environmental health perspectives.

[5]  Developmental toxicity of dichloroacetonitrile: a by-product of drinking water disinfection. , 1989 .

[6]  Debra Silverman,et al.  Bladder cancer and exposure to water disinfection by-products through ingestion, bathing, showering, and swimming in pools. , 2006, American journal of epidemiology.

[7]  Disinfectant By-Products,et al.  Disinfectants and disinfectant by-products , 1987 .

[8]  S. Richardson,et al.  Comparative mammalian cell toxicity of N-DBPs and C-DBPs , 2008 .

[9]  Yin-Tak Woo,et al.  Chemical and biological characterization of newly discovered iodoacid drinking water disinfection byproducts. , 2004, Environmental science & technology.

[10]  L. Zhang,et al.  Bromine-, chlorine-, and mixed halogen-substituted 4-methyl-2(5H)-furanones: synthesis and mutagenic effects of halogen and hydroxyl group replacements. , 1997, Chemical research in toxicology.

[11]  P. Elliott,et al.  Uptake of chlorination disinfection by-products; a review and a discussion of its implications for exposure assessment in epidemiological studies , 2000, Journal of Exposure Analysis and Environmental Epidemiology.

[12]  H. Kay Environmental Health Criteria , 1980 .

[13]  R. Trussell,et al.  NDMA Formation in Water and Wastewater , 2001 .

[14]  S. Richardson,et al.  Occurrence, synthesis, and mammalian cell cytotoxicity and genotoxicity of haloacetamides: an emerging class of nitrogenous drinking water disinfection byproducts. , 2008, Environmental science & technology.

[15]  Z. Alach Australian drinking water guidelines , 2008 .

[16]  J. Klotz,et al.  Neural tube defects and drinking water disinfection by-products. , 1999, Epidemiology.

[17]  J. E. Simmons,et al.  Disinfection byproducts: the next generation. , 2002, Environmental science & technology.

[18]  R. D. Morris,et al.  Chlorination, chlorination by-products, and cancer: a meta-analysis. , 1992, American journal of public health.

[19]  D. DeMarini,et al.  Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: a review and roadmap for research. , 2007, Mutation research.

[20]  S. Swan,et al.  Influence of exposure assessment methods on risk estimates in an epidemiologic study of total trihalomethane exposure and spontaneous abortion , 2001, Journal of Exposure Analysis and Environmental Epidemiology.

[21]  David L. Sedlak,et al.  Precursors of N-Nitrosodimethylamine in Natural Waters , 2003 .

[22]  M. Nieuwenhuijsen,et al.  Chlorination disinfection byproducts in water and their association with adverse reproductive outcomes: a review , 2000, Occupational and environmental medicine.

[23]  M Dosemeci,et al.  Drinking Water Source and Chlorination Byproducts I. Risk of Bladder Cancer , 1998, Epidemiology.

[24]  J. Jaakkola,et al.  Water Chlorination and Birth Defects: A Systematic Review and Meta-Analysis , 2003, Archives of environmental health.

[25]  W. King,et al.  Relation between trihalomethane compounds and birth defects , 2001, Occupational and environmental medicine.

[26]  Andrzej Wilczak,et al.  Formation of NDMA in Chloraminated Water Coagulated with DADMAC Cationic Polymer , 2003 .

[27]  A. Zuckerman,et al.  IARC Monographs on the Evaluation of Carcinogenic Risks to Humans , 1995, IARC monographs on the evaluation of carcinogenic risks to humans.

[28]  J. A. Roberson,et al.  Some drinking-water disinfectants and contaminants, including arsenic. , 2004, IARC monographs on the evaluation of carcinogenic risks to humans.

[29]  G. Olson,et al.  Carcinogenic activity associated with halogenated acetones and acroleins in the mouse skin assay. , 1989, Cancer letters.

[30]  M. Fulcomer,et al.  Public drinking water contamination and birth outcomes. , 1995, American journal of epidemiology.

[31]  S. Richardson,et al.  Drinking Water Disinfection By-products , 2011 .

[32]  S. Richardson,et al.  Occurrence of a new generation of disinfection byproducts. , 2006, Environmental science & technology.

[33]  M Jacobsen,et al.  Re: Carcinogenicity of the drinking water mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone in the rat. , 1997, Journal of the National Cancer Institute.

[34]  R. Hayes Dry cleaning, some chlorinated solvents and other industrial chemicals IARC monographs on the evaluation of carcinogenic risks to humans. volume 63 , 1996, Cancer Causes & Control.

[35]  S. Richardson,et al.  Halonitromethane drinking water disinfection byproducts: chemical characterization and mammalian cell cytotoxicity and genotoxicity. , 2004, Environmental science & technology.

[36]  R. L. Valentine,et al.  Formation of N-nitrosodimethylamine (NDMA) from reaction of monochloramine: a new disinfection by-product. , 2002, Water research.

[37]  S. Hrudey,et al.  Detecting N-nitrosamines in drinking water at nanogram per liter levels using ammonia positive chemical ionization. , 2004, Environmental science & technology.

[38]  D. Barnes,et al.  Reference dose (RfD): description and use in health risk assessments. , 1988, Regulatory toxicology and pharmacology : RTP.

[39]  G. Matanoski,et al.  Weight of evidence for an association between adverse reproductive and developmental effects and exposure to disinfection by-products: a critical review. , 2001, Regulatory toxicology and pharmacology : RTP.

[40]  E. S. Hunter,et al.  Development of a research strategy for integrated technology-based toxicological and chemical evaluation of complex mixtures of drinking water disinfection byproducts. , 2002, Environmental health perspectives.

[41]  T. Kamataki,et al.  Role of human cytochrome P450 (CYP) in the metabolic activation of N-alkylnitrosamines: application of genetically engineered Salmonella typhimurium YG7108 expressing each form of CYP together with human NADPH-cytochrome P450 reductase. , 2001, Mutation research.

[42]  G. Rice,et al.  Estimation of the total daily oral intake of NDMA attributable to drinking water. , 2007, Journal of water and health.

[43]  Nicky Best,et al.  Chlorination Disinfection By-Products and Risk of Congenital Anomalies in England and Wales , 2007, Environmental health perspectives.

[44]  Water chlorination and birth defects , 1999 .

[45]  J. Rook Formation of Haloforms during Chlorination of natural Waters , 1974 .