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The ever‐increasing need for access to safe water has meant that alternative water sources and innovative water reclamation approaches are often required to meet the global water demand. As a result, many wastewater treatment facilities have faced regulatory pressure to seek alternative disinfection methods that ensure public health safety, while adhering to regulations that set limits on carcinogenic disinfection by‐products (DBPs). Peracetic acid (PAA) is an emerging wastewater disinfectant in the United States that has been widely used in other industries such as food sanitization and does not produce carcinogenic DBPs. However, several factors such as transport, storage, and physical and chemical effects have stymied its widespread use in wastewater markets. Therefore, the purpose of this study was to examine the antimicrobial efficacy of an on‐site generated PAA compared against a commercially available PAA. Antimicrobial efficacy was assessed using standard fecal contamination indicators (i.e., total coliforms and Escherichia coli) in six urban wastewater treatment facilities ranging in size and treatment processes. Overall, few statistical differences were found between the antimicrobial efficacies of on‐site generated PAA and commercially available PAA; however, before becoming more widely utilized, the on‐site PAA should be tested against emerging fecal contamination indicators (e.g., human norovirus and enterovirus) and be assessed in terms of economic and sustainability impacts. Practitioner Points: Alternative Ct approaches should be considered when using disinfectants like PAA.On‐site generated PAA can achieve the same level of disinfection as commercial PAA.On‐site generation of PAA may help further its use as a wastewater disinfectant. [ABSTRACT FROM AUTHOR]

In the 1980s, a case–control epidemiologic study was conducted in Iowa (USA) to analyze the association between exposure to disinfection by-products (DBPs) and bladder cancer risk. Trihalomethanes (THMs), the most commonly measured and dominant class of DBPs in drinking water, served as a primary metric and surrogate for the full DBP mixture. Average THM exposure was calculated, based on rough estimates of past levels in Iowa. To reduce misclassification, a follow-up study was undertaken to improve estimates of past THM levels and to re-evaluate their association with cancer risk. In addition, the risk associated with haloacetic acids, another class of DBPs, was examined. In the original analysis, surface water treatment plants were assigned one of two possible THM levels depending on the point of chlorination. The re-assessment considered each utility treating surface or groundwater on a case-by-case basis. Multiple treatment/disinfection scenarios and water quality parameters were considered with actual DBP measurements to develop estimates of past levels. The highest annual average THM level in the re-analysis was 156 μg/L compared to 74 μg/L for the original analysis. This allowed the analysis of subjects exposed at higher levels (> 96 μg/L). The re-analysis established a new approach, based on case studies and an understanding of the water quality and operational parameters that impact DBP formation, for determining historical exposure. [ABSTRACT FROM AUTHOR]

Water utilities are increasingly considering indirect and direct potable reuse of municipal wastewater effluents. Disinfection byproducts (DBPs), particularly N -nitrosamines, are key contaminants of potential health concern for potable reuse. This study quantified the concentrations of N -nitrosamines and a suite of regulated and unregulated halogenated DBPs across five U.S. potable reuse Full Advanced Treatment trains incorporating microfiltration, reverse osmosis, and UV-based advanced oxidation. Low μg/L concentrations of trihalomethanes, haloacetic acids, dichloroacetonitrile, and dichloroacetamide were detected in the secondary or tertiary wastewater effluents serving as influents to potable reuse treatment trains, while the concentrations of N -nitrosamines were more variable (e.g., <2–320 ng/L for N -nitrosodimethylamine). Ozonation promoted the formation of N -nitrosamines, haloacetaldehydes, and haloacetamides, but biological activated carbon effectively reduced concentrations of these DBPs. Application of chloramines upstream of microfiltration for biofouling control increased DBP concentrations to their highest levels observed along the treatment trains. Reverse osmosis rejected DBPs to varying degrees, ranging from low for some (e.g., N -nitrosamines, trihalomethanes, and haloacetonitriles) to high for other DBPs. UV-based advanced oxidation eliminated N -nitrosamines, but only partially removed halogenated DBPs. Chloramination of the treatment train product waters under simulated distribution system conditions formed additional DBPs, with concentrations often equaling or exceeding those in the treatment train influents. Overall, the concentration profiles of DBPs were fairly consistent within individual treatment trains for sampling campaigns separated by months and across different treatment trains for the same sampling time window. Weighting DBP concentrations by their toxic potencies highlighted the potential significance of haloacetonitriles, which were not effectively removed by reverse osmosis and advanced oxidation, to the DBP-associated toxicity in potable reuse waters. [ABSTRACT FROM AUTHOR]

Exposure to trihalomethanes (or THMs: chloroform, bromoform, bromodichloromethane, and dibromochloromethane [DBCM]) formed via drinking water disinfection has been associated with adverse reproductive outcomes and cancers of the digestive or genitourinary organs. However, few studies have examined potential associations between THMs and liver injury in humans, even though experimental studies suggest that these agents exert hepatotoxic effects, particularly among obese individuals. This study examined participants in the National Health and Nutrition Examination Survey (1999–2006, N = 2781) to test the hypothesis that THMs are associated with liver injury as assessed by alanine aminotransferase (ALT) activity in circulation. Effect modification by body mass index (BMI) or alcohol consumption also was examined. Associations between blood THM concentrations and ALT activity were assessed using unconditional multiple logistic regression to calculate prevalence odds ratios (ORs) with 95% confidence intervals (CIs) for exposure among cases with elevated ALT activity (men: >40 IU/L, women: >30 IU/L) relative to those with normal ALT, after adjustment for variables that may confound the relationship between ALT and THMs. Compared to controls, cases were 1.35 times more likely (95% CI: 1.02, 1.79) to have circulating DBCM concentrations exceeding median values in the study population. There was little evidence for effect modification by BMI, although the association varied by alcohol consumption. Among non-drinkers, cases were more likely than controls to be exposed to DBCM (OR: 3.30, 95% CI: 1.37, 7.90), bromoform (OR: 2.88, 95% CI: 1.21, 6.81), or brominated THMs (OR: 4.00, 95% CI: 1.31, 12.1), but no association was observed among participants with low, or moderate to heavy alcohol consumption. Total THM levels exceeding benchmark exposure limits continue to be reported both in the United States and globally. Results from this study suggest a need for further characterization of ALT activity and possibly other hepatic or metabolic diseases in populations with elevated drinking water THM concentrations. [ABSTRACT FROM AUTHOR]

Most utility customers aren't aware of the important role distribution system cleanliness plays in their lives each day. Regular cleaning improves water quality and system performance and reduces public health risks. [ABSTRACT FROM AUTHOR]

The removal of selected Pharmaceuticals and personal care products, atrazine, and disinfection by-product precursors, was evaluated during a pilot-scale study conducted at the Bollman Water Treatment Plant in Concord, California, USA. Treatment alternatives included ozonation followed by biologically active filtration (BAF), and nanofiltration. Both technologies exhibited excellent broad-spectrum removal of the spiked target contaminants. The ozone/BAF system in particular showed a high degree of effectiveness despite relatively low ozone doses corresponding to a low disinfection target (0.5-log Giardia reduction). The BAF system was observed to remove several contaminants that were relatively unreactive with ozone, demonstrating an important synergy between the ozone and BAF. [ABSTRACT FROM AUTHOR]

Abstract: Ultraviolet (UV) irradiation has become popular as a primary disinfectant because it is very effective against Cryptosporidium and does not directly form regulated disinfection by-products. Higher UV doses and UV advanced oxidation (UV/H2O2) processes are under consideration for the treatment of trace organic pollutants (e.g. pharmaceuticals, personal care products). Despite the disinfection effectiveness of UV light, a secondary disinfectant capable of maintaining a distribution system residual is required to meet current U.S. regulation. This study investigated changes in disinfection by-product (DBP) formation attributed to UV or UV/H2O2 followed by application of free chlorine to quench hydrogen peroxide and provide residual disinfectant. At a UV dose of 1000mJ/cm2, trihalomethane (THM) yield increased by up to 4μg/mg-C and 13μg/mg-C when treated with low and medium pressure UV, respectively. With the addition of hydrogen peroxide, THM yield increased by up to 25μg/mg-C (5mg-H2O2/L) and 37μg/mg-C (10mg-H2O2/L). Although no changes in DBPs are expected during UV disinfection, application of UV advanced oxidation followed by chlorine addition was assessed with regard to impacts on DBP formation. [Copyright &y& Elsevier]

Abstract: The formation of disinfection by-products (DBPs) from chlorination and monochloramination of treated drinking waters was determined. Samples were collected after treatment at 11 water treatment works but before exposure to chlorine or monochloramine. Formation potential tests were carried out to determine the DBPs formed by chlorination and monochloramination. DBPs measured were trihalomethanes (THMs), haloacetic acids (HAAs), halonitromethanes (HNMs), haloacetonitriles (HANs), haloaldehydes (HAs), haloketones (HKs) and iodo-THMs (i-THMs). All waters had the potential to form significant levels of all the DBPs measured. Compared to chlorine, monochloramination generally resulted in lower concentrations of DBPs with the exception of 1,1-dichloropropanone. The concentrations of THMs correlated well with the HAAs formed. The impact of bromine on the speciation of the DBPs was determined. The literature findings that higher bromide levels lead to higher concentrations of brominated DBPS were confirmed. [Copyright &y& Elsevier]

Abstract: Haloacetic acids (HAAs) and bromate are toxic water disinfection by-products (DBPs) that the U.S. Environmental Protection Agency has regulated in drinking water. Iodoacetic acids (IAAs) are the emerging DBPs that have been recently found in disinfected drinking waters with higher toxicity than their corresponding chloro- and bromo-acetic acids. This study has developed a new rapid and sensitive method for simultaneous analysis of six brominated and four iodinated acetic acids, bromate, iodate, bromide, and iodide using ion chromatography–inductively coupled plasma-mass spectrometry (IC–ICP-MS). Mono-, di- and tri-chloroacetic acids are not detected by this method because the sensitivity of ICP-MS analysis for chlorine is poor. Following IC separation, an Elan DRC-e ICP-MS was used for detection, with quantitation utilizing m/z of 79, 127, and 74amu for Br, I, and Ge (optional internal standard) species, respectively. Although the primary method used was an external standard procedure, an internal standard method approach is discussed herein as well. Calibration and validation were done in a variety of natural and disinfection-treated water samples. The method detection limits (MDLs) in natural water ranged from 0.33 to 0.72μgL−1 for iodine species, and from 1.36 to 3.28μgL−1 for bromine species. Spiked recoveries were between 67% and 123%, while relative standard deviations ranged from 0.2% to 12.8% for replicate samples. This method was applied to detect the bromine and iodine species in drinking water, groundwater, surface water, and swimming pool water. [Copyright &y& Elsevier]

For evaluation of the adverse health effects associated with exposures to complex chemical mixtures in the environment, the U.S. Environmental Protection Agency (EPA) (2000) states, “if no data are available on the mixture of concern, but health effects data are available on a similar mixture ... a decision must be made whether the mixture on which health effects are available is 'sufficiently' similar to the mixture of concern to permit a risk assessment.” This article provides a detailed discussion of statistical considerations for evaluation of the similarity of mixtures. Multivariate statistical procedures are suggested to determine whether individual samples of drinking-water disinfection by-products (DBPs) vary significantly from a group of samples that are considered to be similar. The application of principal components analysis to (1) reduce the dimensionality of the vectors of water samples and (2) permit visualization and statistical comparisons in lower dimensional space is suggested. Formal analysis of variance tests of homogeneity are illustrated. These multivariate statistical procedures are applied to a data set describing samples from multiple water treatment plants. Essential data required for carrying out sensitive analyses include (1) identification and measurement of toxicologically sensitive process input and output characteristics, and (2) estimates of variability within the data to construct statistically efficient estimates and tests. [ABSTRACT FROM AUTHOR]

There are few measures that can be used to distinguish among mixtures of disinfection by-products (DBPs) produced in the chlorination or chloramination of drinking water. Objective measures of similarities among DBP mixtures would greatly simplify judgments about the risk that may be associated with exposure to DBPs in a given water supply. Major by-products of chlorination/chloramination include the trihalomethanes (THMs) and haloacetic acids (HAAs), which are routinely measured for compliance to regulations. A key question is whether measurement of similar amounts of these DBPs is indicative of the myriad other DBPs that are known to be produced. This article utilized data from a survey of 35 utilities in the United States that included several additional parameters, including members of the haloacetonitrile, trihaloacetaldehyde, and halopropanone classes. Based upon the distribution of bromine in the THM class, the concentrations of unmeasured brominated and bromochlorinated compounds could be determined. This allowed determination of whether measures of the THM and/or HAA classes reflected the amounts of these less abundant classes. Variations in relative yields among DBP classes were observed with water source type and with whether chlorine or chloramine was used as the disinfectant. However, most of the variability was attributable to geographic location. The relative abundance of brominated by-products also varied among water sources. Recent documentation that potent by-products, such as nitrosamines, are selectively produced in particular water systems and preferentially with chloramination indicates that more measures of individual DBP are needed to evaluate similarity among DBPs mixtures. [ABSTRACT FROM AUTHOR]

• Dissolved organic C/residue C decreased significantly with temperatures. • pH, K +, Mg2+, P, PO 4 3−-P, and SO 4 2- in water extracts increased with temperatures. • Parameters by FT-ICR MS and UV/fluorescence were strongly correlated. • H/C and MLB L decreased and AI mod and NOSC increased from no burn to 250 to 400 °C. • Levels of formed DBPs decreased with temperatures. Forested land plays an essential role in water supply across the United States (US). Smoldering commonly existing in wildfires contributes significantly to biomass consumption and gas emission, but its influence on source water quality has been rarely studied. Here, we investigated the impact of smoldering temperature (i.e., no burn, 250, 400, and 600 °C) on the nutrients, elements, and dissolved organic matter (DOM) of water extracts from the residues of the leaf needles and woody trunks of pine (Pinus jeffreyi) under the lab-simulated smoldering fire. Results showed the increase of pH and the yields of the dominated exchangeable cations of K + and Mg2+, P, PO 4 3−-P, and SO 4 2− with increasing temperature increasing from 250 to 600 °C, whereas significant decreases in the fraction of dissolved organic C in residue C with increasing temperature and the yields of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) after burnings. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) presented consistent results with UV/fluorescence, suggesting that the unburned materials contained more biodegradable tyrosine/tryptophan/soluble microbial byproduct-like compounds with high molecular weight (MW), whereas the 600 °C-smoldering materials composed of more aromatic, humified, fulvic/humic acid-like, and oxidized compounds with a potentially high density of C=C bonds had less reactivity in forming trihalomethanes (THMs) and haloacetonitriles (HANs). Our study indicates the smoldering-dominated prescribed fire as a potential forest management strategy for reducing biomass fuel and disinfection byproducts (DBPs) precursors in source water from forested lands. TOC/Abstract Art (original size: 3.33 inches by 1.875 inches) [Display omitted] [ABSTRACT FROM AUTHOR]

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 by-products (DBP) are chemicals formed by the reaction of oxidizing disinfectants with inorganic and organic materials in the source water. To address potential health concerns that cannot be answered directly by toxicological research on individual DBPs or defined DBP mixtures, scientists residing within the various organizations of the U.S. Environmental Protection Agency's Office of Research and Development (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) engaged in joint investigation of environmentally realistic complex mixtures of DBP. Research on complex mixtures of DBP is motivated by three factors: (a) DBP exposure is ubiquitous to all segments of the population; (b) some positive epidemiologic studies are suggestive of potential developmental, reproductive, or carcinogenic health effects in humans exposed to DBP; and (c) significant amounts of the material that makes up the total organic halide portion of the DBP have not been identified. The goal of the Integrated Disinfection Byproducts Mixtures Research Project (the 4Lab Study) is provision of sound, defensible, experimental data on environmentally relevant mixtures of DBP and an improved estimation of the potential health risks associated with exposure to the mixtures of DBP formed during disinfection of drinking water. A phased research plan was developed and implemented. The present series of articles provides the results from the first series of experiments. [ABSTRACT FROM AUTHOR]

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 Environmental Health describe concentration of these finished waters by reverse osmosis techniques, chemical characterization of the resulting disinfection by-product (DBP) concentrates, in vivo and in vitro toxicological results, and risk assessment methods developed to analyze data from this project. This project, called the “Four Lab Study,” involved participation of scientists from four laboratories/centers of the U.S. Environmental Protection Agency Office of Research and Development as well as extramural collaborators from the water industry and academia. One of the two finished waters was prepared by conventional treatment and disinfected by chlorination. The other finished water was also prepared by conventional treatment and disinfected by ozonation followed by chlorination (ozonation/postchlorination). Chlorination conditions of dose, time and temperature were similar for both treatment scenarios, allowing for a comparison. Both finished waters had acceptably low levels of particulates and bacteria, representative pH and chlorine levels, and contained numerous DBP. Known effects of ozonation were observed in that, relative to the water that was chlorinated only, the ozonated/postchlorinated water had lower concentrations of total organic halogen, trihalomethanes (THM), haloacetic acids (HAA), and higher concentrations of bromate, and aldehydes. [ABSTRACT FROM AUTHOR]

This article describes the disinfection by-product (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 DBPs. This project, called the Four Lab Study, involved the participation of scientists from four laboratories and centers of the U.S. Environmental Protection Agency (EPA) Office of Research and Development, along with collaborators from the water industry and academia, and addressed toxicologic effects of complex DBP mixtures, with an emphasis on reproductive and developmental effects that are associated with DBP exposures in epidemiologic studies. Complex mixtures of DBPs from two different disinfection schemes (chlorination and ozonation/postchlorination) were concentrated successfully, while maintaining a water matrix suitable for animal studies. An array of chlorinated/brominated/iodinated DBPs was created. The DBPs were relatively stable over the course of the animal experiments, and a significant portion of the halogenated DBPs formed in the drinking water was accounted for through a comprehensive qualitative and quantitative identification approach. DBPs quantified included priority DBPs that are not regulated but have been predicted to produce adverse health effects, as well as those currently regulated in the United States and those targeted during implementation of the Information Collection Rule. New by-products were also reported for the first time. These included previously undetected and unreported bromo- and chloroacids, iodinated compounds, bromo- and iodophenols, and bromoalkyltins. [ABSTRACT FROM AUTHOR]

Disinfection by-products (DBPs) in drinking water may be associated with adverse pregnancy outcomes. However, the results from previous epidemiological studies are not consistent, perhaps in part due to individual variation in water use and consumption. This study was performed to evaluate and describe demographic and behavioral characteristics as predictors of ingested water, showering, bathing, and swimming among pregnant women. Water use and consumption data were collected through telephone interviews with 2297 pregnant women from three geographical sites in the southern United States. The data were analyzed according to demographic, health, and behavioral variables expected to be predictors of water use and thus potential confounding factors relating water use to pregnancy outcome. The candidate predictors were evaluated using backward elimination in regression models. Demographic variables tended to be more strongly predictive of the use and consumption of water than health and behavior-related factors. Non-Hispanic white women drank 0.4 (95% confidence interval (CI) 0.2; 0.7) liters more cold tap water per day than Hispanic women and 0.3 (95% CI 0.1; 0.4) liters more than non-Hispanic black women. Non-Hispanic white women also reported drinking a higher proportion of filtered tap water, whereas Hispanic women replaced more of their tap water with bottled water. Lower socioeconomic groups reported spending a longer time showering and bathing, but were less likely to use swimming pools. The results of this study should help researchers to anticipate and better control for confounding and misclassification in studies of exposure to DBPs and pregnancy outcomes.Journal of Exposure Science and Environmental Epidemiology (2007) 17, 159–169. doi:10.1038/sj.jes.7500488; published online 3 May 2006 [ABSTRACT FROM AUTHOR]

N-Nitrosodimethylamine (NDMA), a member of a group of probable human carcinogens, has been detected as a disinfection byproduct (DBP) in drinking water supplies in Canada and the United States. To comprehensively investigate the occurrence of possible nitrosamines in drinking water supplies, a liquid chromatography-tandem mass spectrometry technique was developed to detect both thermally stable and unstable nitrosamines. This technique consisted of solid-phase extraction (SPE), liquid chromatography (LC) separation, and tandem quadrupole linear ion trap mass spectrometry (MS/MS) detection. It enabled the determination of sub-ng/L levels of nine nitrosamines. Isotope-labeled N-nitrosodimethylamine-d6 (NDMA-d6) was used as the surrogate standard for determining recovery, and N-nitrosodi-n-propylamine-d14 (NDPA-d14) was used as the internal standard for quantification. The method detection limits were estimated to be 0.1–10.6 ng/L, and the average recoveries were 41–111% for the nine nitrosamines; of these, NDMA, N-nitrosopyrrolidine (NPyr), N-nitrosopiperidine (NPip), and N-nitrosodiphenylamine (NOPhA) were identified and quantified in drinking water samples collected from four locations within the same distribution system. In general, the concentrations of these four nitrosamines in this distribution system increased with increasing distance from the water treatment plant, indicating that the amount of formation was greater than the amount of decomposition within this time frame. The identification of NPip and NOPhA in drinking water systems and the distribution profiles of these nitrosamines have not been reported previously. These nitrosamines are toxic, and their presence as DBPs in drinking water may have toxicological relevance. [ABSTRACT FROM AUTHOR]

Jar tests were conducted on six source waters from softening plants throughout the United States to evaluate the extent of softening, natural organic matter (NOM) removal, and reduction in disinfection by-product (DBP) formation achieved by varying lime doses. Results demonstrated the effect of source water characteristics, e.g., specific ultraviolet absorbance (SUVA), bromide, and total organic carbon (TOC) on the potential for softening to remove NOM and reduce DBP formation. The source water exhibiting the lowest SUVA value had the lowest degree of NOM removal, and the source water with the highest bromide concentration showed substantial formation of bromine-substituted DBPs. These results confirmed previous observations that enhanced softening improves removal of dissolved organic carbon, decreases SUVA values, and decreases formation of dissolved organic halogen. The research also showed that both calcium carbonate and magnesium hydroxide are responsible for NOM removal in softening. With the exception of Lake Austin (Texas) source water, the waters studied would require softening to the point of magnesium hydroxide precipitation to meet required TOC removals and (in some cases) to meet the maximum contaminant level for total trihalomethanes and the sum of five haloacetic acids with lime softening alone. [ABSTRACT FROM AUTHOR]

The article discusses the scientific and policy considerations on the health risks of disinfection by-products (DPBs) in drinking water in the U.S. The presence of DBPs in drinking water was first reported in 1974, wherein it was linked to the process of chlorination. It was discovered that DBPs cause cancer on the digestive and urinary tracts. The Environmental Protection Agency has already regulated the use of the treatment while research are performed on its effects and alternative solutions. However, limitations on the study and the lack of cooperation are just adding up to the problem. Presently, the process of chloramination is used, however, this solution is for temporary use only and thorough studies are needed to bring out permanent and long-term solutions. INSET: The Athalie Richardson Irvine Clarke Prize.

The article focuses on a survey done by the American Water Works Association's (AWWA) Secondary Disinfection Practices Survey to determine the percentage of water utilities currently using chloramines and those intending to convert to the use of chloramines in the future in the United States. Chloramines have been utilized as a disinfectant for many years. Their long-term stability in distribution systems and tendency to form only low levels of regulated disinfection by-products make them attractive as a secondary disinfectant. There are however, some known drawbacks to using chloramines, such as nitrification and gasket material failures. The national use of chloramines is at the center of several current drinking water policy discussions. The AWWA Secondary Disinfection Practices Survey provides a large survey response to compare estimates regarding the use of chloramines with the economic analysis predictions. This survey does not represent a random sampling of all drinking water utilities, but rather a sampling of those utilities willing to complete the survey.

Presents topics involving the efficacy testing of disinfectants published in "General Referee Reports" section of "Journal of AOAC International." Discussion on the responsibility of the U.S. Environmental Protection Agency's Office of Pesticide Programs to regulate antimicrobial products used to treat and decontaminate inanimate surfaces; Initiation of research to evaluate and improve efficacy test methods for sporicides in response to anthrax attacks; Development and comparative testing of the AOAC Sporicidal Activity Test.

Epidemiologic studies of disinfection by-products have traditionally focused on total trihalomethane (TTHM) concentration as a surrogate for maternal exposure during pregnancy. We used birth certificate data on 196,000 infants to examine the effect of third-trimester exposures on various indices of fetal development. We examined the effect of town-average concentrations of TTHM and additional exposure metrics in relation to mean birth weight, mean gestational age, small for gestational age (SGA) infancy, and preterm delivery. Trihalomethane data (TTHM, chloroform, and bromo-dichloromethane) from 1995–1998 were available for 109 towns in Massachusetts. Data from 1997–1998 on haloacetic acid (total haloacetic acids, dichloroacetic acid, and trichloroacetic acid), 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), and mutagenicity were available for a limited number of towns. We observed reductions in mean birth weight (12–18 g) for maternal trihalomethane exposures > the 90th percentile compared with those < the 50th percentile. Birth weight reductions were detected for chloroform exposures > 20 μg/L and TTHM exposures > 40 lag/L. Elevated trihalomethanes were associated with increases in gestational duration and a reduced risk of preterm delivery. We found evidence of an exposure-response effect of trihalomethanes on risk of SGA, with odds ratios (ORs) ranging from 1.09 to 1.23 for bromodichloromethane exposures > 5 μg/L. Elevated mutagenic activity was associated with SGA [OR = 1.25; 95% confidence interval (CI), 1.04 to 1.51] and mean birth weight (-27 g; 95% CI, -54 to -1). Although smaller in magnitude, our findings are consistent with previous studies reporting associations between trihalomethanes and SGA. These data also suggest a relationship between fetal development indices and mutagenic activity independent of exposure to trihalomethanes, haloacetic acids, and MX. [ABSTRACT FROM AUTHOR]

Discusses the complaints of the American Water Works Association with the Stage 2 Disinfectants/Disinfection Byproducts Rule (S2D/DBPR) proposed by the U.S. Environmental Protection Agency (USEPA) in August 2003. Provisions of the proposed rule; Early implementation requirements proposed by USEPA; Concerns over proposed monitoring scheme for initial distribution system evaluations to identify sites for S2D/DBPR compliance monitoring and for routine compliance monitoring.

Reports on the implementation of the Safe Drinking Water Act (SDWA) in the U.S. which was first enacted by the Environmental Protection Agency (USEPA) in 1974. Requirements of USEPA for contaminant regulation; Details of the microbial/disinfection by-product cluster; Specifications of the SDWA review process.

Halonitromethanes are drinking water disinfection byproducts that have recently received a high priority for health effects research from the U.S. Environmental Protection Agency (EPA). Our purpose was to identify and synthesize where necessary the mixed halonitromethanes and to determine the chronic cytotoxicity and the acute genotoxicity of these agents in mammalian cells. The halonitromethanes included bromonitromethane (BNM), dibromonitromethane (DBNM), tribromonitromethane (TBNM), bromochloronitromethane (BCNM), dibromochloroni-tromethane (DBCNM), bromodichloronitromethane (BDCNM), chloronitromethane (CNM), dichloronitromethane (DCNM), and trichloronitromethane (TCNM). Low- and high-resolution gas chromatography/mass spectrometry (GC/MS) was used to identify the mixed chloro-bromo-nitromethanes in finished drinking waters, and analytical standards that were not commercially available were synthesized (BDCNM, DBCNM, TBNM, CNM, DCNM, BCNM). The rank order of their chronic cytotoxicity (72 h exposure) to Chinese hamster ovary (CHO) cells was DBNM > DBCNM > BNM > TBNM > BDCNM > BCNM > DCNM > CNM > TCNM. The rank order to induce genomic DNA damage in CHO cells was DBNM > BDCNM > TBNM TCNM > BNM > DBCNM > BCNM > DCNM CNM. The brominated nitromethanes were more cytotoxic and genotoxic than their chlorinated analogues. This research demonstrated the integration of the procedures for the analytical chemistry and analytical biology when working with limited amounts of sample. The halonitromethanes are potent mammalian cell cytotoxins and genotoxins and may pose a hazard to the public health and the environment. [ABSTRACT FROM AUTHOR]

Deals with the efforts of the Association of State Drinking Water Administrators (ASDWA) to persuade the U.S. Environmental Protection Agency (USEPA) to delay implementation of the Stage 2 Disinfectants/Disinfection Byproducts Rule until the two year postpromulgation deadline for states to obtain primary reinforcement authority. Background on the proposed Long Term 2 Enhanced Surface Water Treatment Rule; Reason of ASDWA for objecting to the proposed approach by USEPA for defining and dealing with significant excursions; Factors that could influence water distribution systems.

If your distribution system uses chloramines as a secondary disinfectant and you want to improve operation, you aren't alone. During the past decade, many water utilities have switched to chloramination to satisfy US Environmental Protection Agency (USEPA) secondary disinfection requirements, primarily to meet disinfection by‐product regulations, including trihalomethanes. [ABSTRACT FROM AUTHOR]

The article reports that alternative methods to disinfect water without chlorine have created a whole new suite of byproducts that might affect human health in the U.S. A study was conducted on drinking water treatment systems in regions with compromised source waters documents 28 new disinfection byproducts. Twelve water treatment plants were selected representing a variety of possible treatment technologies and local conditions. A conclusion has been drawn, signifying that source waters which is high in total organic carbon or bromide tend to lead to potential problems.

The article presents information on disinfection by-products. Chlorine is the most widely used water disinfectant because of its effectiveness and cost. Research shows that chlorine has side effects. It reacts with organic matter present in water and forms a series of compounds that have been linked to cancer in animals. All living organisms have carbon as an essential element in their cells. When trees shed their leaves, they start decomposing and are ultimately broken down by bacteria into carbon-containing compounds. Similarly, dead animals on land and fish and other aquatic life decompose and disintegrate into compounds that contain carbon as an essential element. Disinfection can produce hundreds of by-products when chlorine reacts with organic matter. In 1979, the U.S. Environmental Protection Agency adopted regulations that established a maximum contaminant level of 0.1 mg/L for total trihalomethane.

The article reports that according to the Government Accountability Office in the U.S., plumbing standards that can't be enforced are hindering efforts to reduce lead in drinking water. Experts from regulatory agencies, industry and trade associations say that a lack of enforcement is worsening a conflict between regulations designed to reduce disinfection byproducts and those aimed at minimizing lead in drinking water. Voluntary standards for lead leachability exist for household plumbing fixtures which are implemented through plumbing codes that vary in every state and are difficult to enforce.

Reports updates involving the committee on pesticides and disinfectant formulations in the U.S. Lists of members in the committee; Program of activities of the committee; Relocation of the Study Director for Pendimathalian Formulations.

Reports on the study about the health risks of disinfection by-products in the U.S. Chlorination of public water to reduce waterborne diseases; Prevalence of trihalomethane; Association between mutagenic activity and mean birth weight.

Discusses a research report released by the U.S. Environmental Protection Agency (USEPA) on January 7, 2004, about the feasibility of assessing the cumulative cancer and reproductive risks posed by disinfection by-products (DBP) during water treatment. Introduction of the cumulative relative potency factors (CRPF) method by USEPA; Process for conducting the CRPF assessment; Conclusion on the multiple-route exposure estimates.

Focuses on the rules proposed by the U.S. Environmental Protection Agency to protect water systems against Cryptosporidium and expand control of disinfection byproducts. Long Term 2 Enhanced Surface Water Treatment Rule; Stage 2 Disinfection Byproducts Rule.

The article talks about the comments of the American Water Works Association(AWWA) regarding the draft guidance manual from the United States Environmental Protection Agency(USEPA). AWWA stresses that draft is a useful guide which needs to be fleshed out with substantial information to aid utilities avoid unintended consequences in their efforts to control both microbial contaminants and disinfection byproducts. The association also states that the manual requires the readers to look elsewhere for guidance on compliance decisions.

The article reports on the two published regulation that tightens controls for microbials and disinfection byproducts by the U.S. Environmental Protection Agency. Under the Long-Term 2 enhanced Surface Water Treatment Rule, drinking-water utilities are directed to intensify their monitoring and treatment for waterborne microbial pathogens. Likewise, the Stage 2 Disinfectants and DBP Rule directs utilities to simultaneously understate the presence of substance that contaminates known as disinfections byproducts.

The article presents information on a study conducted at the University of North Carolina at Chapel Hill, published online by the American Water Works Association Research Foundation, according to which disinfection byproducts (DBPs) in drinking water are not associated with miscarriages or other reproductive problems. Scientists with expertise in the issue say that the results contradict an influential 1998 article and suggest that the U.S. Environmental Protection Agency's DBP regulations are sufficiently protective. Epidemiologist Mark Nieuwenhuijsen at Imperial College London says that it is a study that was well conducted, and the methodology is greatly improved compared to other studies, particularly the exposure assessment side. The research was motivated by a 1998 California study that found that women exposed to higher DBP levels had an increased risk of miscarriage. In the new study, epidemiologist David Savitz and colleagues followed more than 3000 women from before conception or early in their pregnancy through birth. They monitored the DBP content of drinking water at the tap on a weekly or biweekly basis in three representative cities with well-run water utilities.