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Stanton, T., Johnson, M., Nathanail, P., Gomes, R.L., Needham, T., Burson, A., 2019.

ABSTRACT: The presence of microplastic particles (<5 mm) in the environment has generated considerable concern across public, political, and scientific platforms. However, the diversity of microplastics that persist in the environment poses complex analytical challenges for our understanding of their prevalence. The use of the dye Nile red to quantify microplastics is increasingly common. However, its use in microplastic analysis rarely accounts for its affinity with the breadth of particles that occur in environmental samples. Here, we examine Nile red’s ability to stain a variety of microplastic particles and common natural and anthropogenic particles found in environmental samples. To better constrain microplastic estimates using Nile red, we test the coapplication of a second stain that binds to biological material, 4′,6-diamidino-2-phenylindole (DAPI). We test the potential inflation of microplastic estimates using Nile red alone by applying this costaining approach to samples of drinking water and freshwater. The use of Nile red dye alone resulted in a maximum 100% overestimation of microplastic particles. These findings are of particular significance for the public dissemination of findings from an emotive field of study.

https://doi.org/10.1021/acs.estlett.9b00499

Author Full Names: Ciofi, Lorenzo; Renai, Lapo; Rossini, Daniele; Ancillotti, Claudia; Falai, Alida; Fibbi, Donatella; Bruzzoniti, Maria Concetta; Juan Santana-Rodriguez, Jose; Orlandini, Serena; Del Bubba, Massimo
Source: TALANTA, 176 412-421; 10.1016/j.talanta.2017.08.052JAN 1 2018
Language: English

Abstract: The applicability of a direct injection UHPLC-MS/MS method for the analysis of several perfluoroalkyl acids (PFAAs) in a wide range of water matrices was investigated. The method is based on the direct injection of 100 mu L of centrifuged water sample, without any other sample treatment. Very good method detection limits (0.014-0.44 mu g L-1) and excellent intra and inter-day precision (RSD% values in the range 1.8-4.4% and 2.7-5.7%, respectively) were achieved, with a total analysis time of 20 min per sample. A high number of samples i.e. 8 drinking waters (DW), 12 ground waters (GW), 13 surface waters (SW), 8 influents and 11 effluents of wastewater treatment plants (WWTPIN and WWTPOUT) were processed and the extent of matrix effect (ME) was calculated, highlighting the strong prevalence of vertical bar ME vertical bar < 20%. The occurrence of vertical bar ME vertical bar > 50% was occasionally observed only for perfluorooctanesulphonic and perfluorodecanoic acids. Linear discriminant analysis highlighted the great contribution of the sample origin (i.e. DW, GW, SW, WWTPIN and WWTPOUT) to the ME. Partial least square regression (PLS) and leave-one-out cross-validation were performed in order to interpret and predict the signal suppression or enhancement phenomena as a function of physicochemical parameters of water samples (i.e. conductivity, hardness and chemical oxygen demand) and background chromatographic area. The PLS approach resulted only in an approximate screening, due to the low prediction power of the PLS models. However, for most analytes in most samples, the fitted and cross-validated values were such as to correctly distinguish between vertical bar ME vertical bar higher than 20% or below this limit. PFAAs in the aforementioned water samples were quantified by means of the standard addition method, highlighting their occurrence mainly in WWTP influents and effluents, at concentrations as high as one hundred of mu g L-1.

Author Full Names: Williamson, Craig E.; Madronich, Sasha; Lal, Aparna; Zepp, Richard G.; Lucas, Robyn M.; Overholt, Erin P.; Rose, Kevin C.; Schladow, S. Geoffrey; Lee-Taylor, Julia
Source: SCIENTIFIC REPORTS, 7 10.1038/s41598-017-13392-2OCT 12 2017
Language: English

Abstract: Climate change is accelerating the release of dissolved organic matter (DOM) to inland and coastal waters through increases in precipitation, thawing of permafrost, and changes in vegetation. Our modeling approach suggests that the selective absorption of ultraviolet radiation (UV) by DOM decreases the valuable ecosystem service wherein sunlight inactivates waterborne pathogens. Here we highlight the sensitivity of waterborne pathogens of humans and wildlife to solar UV, and use the DNA action spectrum to model how differences in water transparency and incident sunlight alter the ability of UV to inactivate waterborne pathogens. A case study demonstrates how heavy precipitation events can reduce the solar inactivation potential in Lake Michigan, which provides drinking water to over 10 million people. These data suggest that widespread increases in DOM and consequent browning of surface waters reduce the potential for solar UV inactivation of pathogens, and increase exposure to infectious diseases in humans and wildlife.

Author(s): Meena K. Yadav; Short, M. D.; Rupak Aryal; Gerber, C.; Akker, B. van der; Saint, C. P.
Source: Water Research, 124 713-727; 10.1016/j.watres.2017.07.0682017

Abstract: This review critically evaluates the types and concentrations of key illicit drugs (cocaine, amphetamines, cannabinoids, opioids and their metabolites) found in wastewater, surface water and drinking water sources worldwide and what is known on the effectiveness of wastewater treatment in removing such compounds. It is also important to amass information on the trends in specific drug use as well as the sources of such compounds that enter the environment and we review current international knowledge on this. There are regional differences in the types and quantities of illicit drug consumption and this is reflected in the quantities detected in water. Generally, the levels of illicit drugs in wastewater effluents are lower than in raw influent, indicating that the majority of compounds can be at least partially removed by conventional treatment processes such as activated sludge or trickling filters. However, the literature also indicates that it is too simplistic to assume non-detection equates to drug removal and/or mitigation of associated risks, as there is evidence that some compounds may avoid detection via inadequate sampling and/or analysis protocols, or through conversion to transformation products. Partitioning of drugs from the water to the solids fraction (sludge/biosolids) may also simply shift the potential risk burden to a different environmental compartment and the review found no information on drug stability and persistence in biosolids. Generally speaking, activated sludge-type processes appear to offer better removal efficacy across a range of substances, but the lack of detail in many studies makes it difficult to comment on the most effective process configurations and operations. There is also a paucity of information on the removal effectiveness of alternative treatment processes. Research is also required on natural removal processes in both water and sediments that may over time facilitate further removal of these compounds in receiving environments.

Author Full Names: Guilherme, Stephanie; Rodriguez, Manuel J.
Source:ENVIRONMENTAL MONITORING AND ASSESSMENT, 189 (11):10.1007/s10661-017-6296-5NOV 2017
Language:English

Abstract: Among all the organic disinfection by-products (DBPs), only trihalomethanes (THMs) and haloacetic acids (HAAs) are regulated in drinking water, while most DBPs are not. Very little information exists on the occurrence of non-regulated DBPs, particularly in small water systems (SWS). Paradoxically, SWS are more vulnerable to DBPs because of a low capacity to implement adequate treatment technologies to remove DBP precursors. Since DBP analyses are expensive, usually SWS have difficulties to implement a rigorous characterization of these contaminants. The purpose of this study was to estimate non-regulated DBP levels in SWS from easy measurements of relevant parameters regularly monitored. Since no information on non-regulated DBPs in SWS was available, a sampling program was carried out in 25 SWS in two provinces of Canada. Five DBP families were investigated: THMs, HAAs, haloacetonitriles (HANs), halonitromethanes (HNMs), and haloketones (HKs). Multivariate linear mixed regression models were developed to estimate HAN, HK, and HNM levels from water quality characteristics in the water treatment plant, concentrations of regulated DBPs, and residual disinfectant levels. The models obtained have a good explanatory capacity since R-2 varies from 0.77 to 0.91 according to compounds and conditions for application (season and type of treatment). Model validation with an independent database suggested their ability for generalization in similar SWS in North America.

Author Full Names: Zartarian, Valerie; Xue, Jianping; Tornero-Velez, Rogelio; Brown, James
Source:ENVIRONMENTAL HEALTH PERSPECTIVES, 125 (9):10.1289/EHP1605SEP 2017
Language:English

Abstract: BACKGROUND: Drinking water and other sources for lead are the subject of public health concerns around the Flint, Michigan, drinking water and East Chicago, Indiana, lead in soil crises. In 2015, the U.S. Environmental Protection Agency (EPA)’s National Drinking Water Advisory Council (NDWAC) recommended establishment of a “health-based, household action level” for lead in drinking water based on children’s exposure.

OBJECTIVES: The primary objective was to develop a coupled exposure-dose modeling approach that can be used to determine what drinking water lead concentrations keep children’s blood lead levels (BLLs) below specified values, considering exposures from water, soil, dust, food, and air. Related objectives were to evaluate the coupled model estimates using real-world blood lead data, to quantify relative contributions by the various media, and to identify key model inputs.

METHODS: A modeling approach using the EPA’s Stochastic Human Exposure and Dose Simulation (SHEDS)-Multimedia and Integrated Exposure Uptake and Biokinetic (IEUBK) models was developed using available data. This analysis for the U.S. population of young children probabilistically simulated multimedia exposures and estimated relative contributions of media to BLLs across all population percentiles for several age groups.

RESULTS: Modeled BLLs compared well with nationally representative BLLs (0-23% relative error). Analyses revealed relative importance of soil and dust ingestion exposure pathways and associated Pb intake rates; water ingestion was also a main pathway, especially for infants.

CONCLUSIONS: This methodology advances scientific understanding of the relationship between lead concentrations in drinking water and BLLs in children. It can guide national health-based benchmarks for lead and related community public health decisions. https://doi.org/10.1289/EHP1605.

Author Full Names: Gibson, Jacqueline MacDonald; Pieper, Kelsey J.
Source:ENVIRONMENTAL HEALTH PERSPECTIVES, 125 (7):10.1289/EHP890JUL 2017
Language:English

Abstract: BACKGROUND: Evidence suggests that the 44.5 million U.S. residents drawing their drinking water from private wells face higher risks of waterborne contaminant exposure than those served by regulated community water supplies. Among U.S. states, North Carolina (N.C.) has the second-largest population relying on private wells, making it a useful microcosm to study challenges to maintaining private-well water quality.

OBJECTIVES: This paper summarizes recommendations from a two-day summit to identify options to improve drinking-water quality for N.C. residents served by private wells. METHODS: The Research Triangle Environmental Health Collaborative invited 111 participants with knowledge of private-well water challenges to attend the Summit. Participants worked in small groups that focused on specific aspects and reconvened in plenary sessions to formulate consensus recommendations.

DISCUSSION: Summit participants highlighted four main barriers to ensuring safe water for residents currently relying on private wells: (1) a database of private well locations is unavailable; (2) racial disparities have perpetuated reliance on private wells in some urbanized areas; (3) many private well users lack information or resources to monitor and maintain their wells; and (4) private-well support programs are fragmented and lack sufficient resources. The Summit produced 10 consensus recommendations for ways to overcome these barriers.

CONCLUSIONS: The Summit recommendations, if undertaken, could improve the health of North Carolinians facing elevated risks of exposure to waterborne contaminants because of their reliance on inadequately monitored and maintained private wells. Because many of the challenges in N.C. are common nationwide, these recommendations could serve as models for other states.

Twenty-five years ago, in a commentary published in Pediatrics, Drs Needleman and Jackson¹ asked whether we would still be treating lead poisoning in the 21st century. Unfortunately, despite considerable progress, our public health system is still failing to prevent children from being lead poisoned and the specter of lead poisoning continues to cast a shadow over the country: over 500 000 American children have a blood lead level of >5 μg/dL (>50 ppb); 23 million homes have 1 or more lead hazards; an unknown number of Americans drink water from lead service lines; and federal standards for lead in house dust, soil, and water fail to protect children. We have understandably focused on the plight of children in Flint, Michigan, but children in hundreds of other cities have blood lead levels higher than the children of Flint.

http://pediatrics.aappublications.org/content/early/2017/07/14/peds.2017-1400

Benedict KM, Reses H, Vigar M, et al. Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water — United States, 2013–2014. MMWR Morb Mortal Wkly Rep 2017;66:1216–1221. DOI: http://dx.doi.org/10.15585/mmwr.mm6644a3

Provision of safe water in the United States is vital to protecting public health (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to CDC through the National Outbreak Reporting System (NORS) (https://www.cdc.gov/healthywater/surveillance/index.html). During 2013–2014, 42 drinking water–associated^† outbreaks were reported, accounting for at least 1,006 cases of illness, 124 hospitalizations, and 13 deaths. Legionella was associated with 57% of these outbreaks and all of the deaths. Sixty-nine percent of the reported illnesses occurred in four outbreaks in which the etiology was determined to be either a chemical or toxin or the parasite Cryptosporidium. Drinking water contamination events can cause disruptions in water service, large impacts on public health, and persistent community concern about drinking water quality. Effective water treatment and regulations can protect public drinking water supplies in the United States, and rapid detection, identification of the cause, and response to illness reports can reduce the transmission of infectious pathogens and harmful chemicals and toxins.

Nearly a third of U.S. adults are not hydrated enough, and poorer adults as well as Black and Hispanic adults are at higher risk for poor hydration than wealthier and white adults, according to a new study from Harvard T.H. Chan School of Public Health.

Lack of access to clean, safe drinking water—as highlighted by recent water crises in communities such as Flint, Michigan—may be one of the main reasons for the disparities, the authors suggested.

The study appeared online July 20, 2017 in the American Journal of Public Health.

Martin, J.A., et al., Critical Reviews in Microbiology, November 2013

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.

Brusseau, M.L. and Narter, M., Ground Water, November 2013

Chlorinated-solvent compounds are among the most common groundwater contaminants in the United States. A majority of the many sites contaminated by chlorinated-solvent compounds are located in metropolitan areas, and most such areas have one or more chlorinated-solvent contaminated sites. Thus, contamination of groundwater by chlorinated-solvent compounds may pose a potential risk to the sustainability of potable water supplies for many metropolitan areas. The impact of chlorinated-solvent sites on metropolitan water resources was assessed for Tucson, Arizona, by comparing the aggregate volume of extracted groundwater for all pump-and-treat systems associated with contaminated sites in the region to the total regional groundwater withdrawal. The analysis revealed that the aggregate volume of groundwater withdrawn for the pump-and-treat systems operating in Tucson, all of which are located at chlorinated-solvent contaminated sites, was 20% of the total groundwater withdrawal in the city for the study period. The treated groundwater was used primarily for direct delivery to local water supply systems or for reinjection as part of the pump-and-treat system. The volume of the treated groundwater used for potable water represented approximately 13% of the total potable water supply sourced from groundwater, and approximately 6% of the total potable water supply. This case study illustrates the significant impact chlorinated-solvent contaminated sites can have on groundwater resources and regional potable water supplies.

Cappello, M.A., et. al., Journal of Environmental Health, November 2013

In the study discussed in this article, 27 private drinking water wells located in a rural Colorado mountain community were sampled for radon contamination and compared against (a) the U.S. Environmental Protection Agency’s (U.S. EPA’s) proposed maximum contaminant level (MCL), (b) the U.S. EPA proposed alternate maximum contaminate level (AMCL), and (c) the average radon level measured in the local municipal drinking water system. The data from the authors’ study found that 100% of the wells within the study population had radon levels in excess of the U.S. EPA MCL, 37% were in excess of the U.S. EPA AMCL, and 100% of wells had radon levels greater than that found in the local municipal drinking water system. Radon contamination in one well was found to be 715 times greater than the U.S. EPA MCL, 54 times greater than the U.S. EPA AMLC, and 36,983 times greater than that found in the local municipal drinking water system. According to the research data and the reviewed literature, the results indicate that this population has a unique and elevated contamination profile and suggest that radon-contaminated drinking water from private wells can present a significant public health concern.

Patterson, K.Y., et. al., Journal of Food Composition and Analysis, August 2013

The composition of tap water contributes to dietary intake of minerals. The Nutrient Data Laboratory (NDL) of the United States Department of Agriculture (USDA) conducted a study of the mineral content of residential tap water, to generate current data for the USDA National Nutrient Database. Sodium, potassium, calcium, magnesium, iron, copper, manganese, phosphorus, and zinc content of drinking water were determined in a nationally representative sampling. The statistically designed sampling method identified 144 locations for water collection in winter and spring from home taps. Assuming a daily consumption of 1 L of tap water, only four minerals (Cu, Ca, Mg, and Na), on average, provided more than 1% of the US dietary reference intake. Significant decreases in calcium were observed with chemical water softeners, and between seasonal pickups for Mg and Ca. The variance of sodium was significantly different among regions (p < 0.05) but no differences were observed as a result of collection time, water source or treatment. Based on the weighted mixed model results, there were no significant differences in overall mineral content between municipal and well water. These results, which are a nationally representative dataset of mineral values for drinking water available from home taps, provides valuable additional information for assessment of dietary mineral intake.

Allevi, R.P., et al., Journal of Water and Health, June 2013

Over one million households rely on private water supplies (e.g. well, spring, cistern) in the Commonwealth of Virginia, USA. The present study tested 538 private wells and springs in 20 Virginia counties for total coliforms (TCs) and Escherichia coli along with a suite of chemical contaminants. A logistic regression analysis was used to investigate potential correlations between TC contamination and chemical parameters (e.g. NO3(-), turbidity), as well as homeowner-provided survey data describing system characteristics and perceived water quality. Of the 538 samples collected, 41% (n = 221) were positive for TCs and 10% (n = 53) for E. coli. Chemical parameters were not statistically predictive of microbial contamination. Well depth, water treatment, and farm location proximate to the water supply were factors in a regression model that predicted presence/absence of TCs with 74% accuracy. Microbial and chemical source tracking techniques (Bacteroides gene Bac32F and HF183 detection via polymerase chain reaction and optical brightener detection via fluorometry) identified four samples as likely contaminated with human wastewater.

Gerke, et al., Environmental Science and Technology, April 22, 2013.

The United States Environmental Protection Agency (US EPA) will require some U.S. drinking water distribution systems (DWDS) to monitor nonradioactive strontium (Sr2+) in drinking water in 2013. Iron corrosion products from four DWDS were examined to assess the potential for Sr2+ binding and release. Average Sr2+ concentrations in the outermost layer of the corrosion products ranged from 3 to 54 mg kg–1 and the Sr2+ drinking water concentrations were all ≤0.3 mg L–1. Micro-X-ray adsorption near edge structure spectroscopy and linear combination fitting determined that Sr2+ was principally associated with CaCO3. Sr2+ was also detected as a surface complex associated with α-FeOOH. Iron particulates deposited on a filter inside a home had an average Sr2+ concentration of 40.3 mg kg–1 and the associated drinking water at a tap was 210 μg L–1. The data suggest that elevated Sr2+ concentrations may be associated with iron corrosion products that, if disturbed, could increase Sr2+ concentrations above the 0.3 μg L–1 US EPA reporting threshold. Disassociation of very small particulates could result in drinking water Sr2+ concentrations that exceed the US EPA health reference limit (4.20 mg kg–1 body weight).

Rubin, S.J., Journal, American Water Works Association, March 2013

US Environmental Protection Agency data were analyzed for violations by community water systems (CWSs). Several characteristics were evaluated, including size, source water, and violation type. The data show that: (1) 55% of CWSs violated at least one regulation under the Safe Drinking Water Act that involved systems serving more than 95 million people; (2) the presence of violations was no different for groundwater and surface water systems; (3) fewer than 20% of CWSs with violations exceeded an allowable level of a contaminant in drinking water; (4) smaller water systems are no more likely than larger systems, except very large systems, to violate health-related requirements; and (5) smaller CWSs appear more likely than larger systems to violate monitoring, reporting, and notification requirements. An evaluation was also conducted of four contaminants that had health-related violations by more than 1% of CWSs: total coliform, stage 1 disinfection by-products, arsenic, and lead and copper.

Triantafyllidou, S., et al., Environmental Monitoring and Assessment, February 2013

Assessing the health risk from lead (Pb) in potable water requires accurate quantification of the Pb concentration. Under worst-case scenarios of highly contaminated water samples, representative of public health concerns, up to 71-98 % of the total Pb was not quantified if water samples were not mixed thoroughly after standard preservation (i.e., addition of 0.15 % (v/v) HNO(3)). Thorough mixing after standard preservation improved recovery in all samples, but 35-81 % of the total Pb was still un-quantified in some samples. Transfer of samples from one bottle to another also created high errors (40-100 % of the total Pb was un-quantified in transferred samples). Although the United States Environmental Protection Agency’s standard protocol avoids most of these errors, certain methods considered EPA-equivalent allow these errors for regulatory compliance sampling. Moreover, routine monitoring for assessment of human Pb exposure in the USA has no standardized protocols for water sample handling and pre-treatment. Overall, while there is no reason to believe that sample handling and pre-treatment dramatically skew regulatory compliance with the US Pb action level, slight variations from one approved protocol to another may cause Pb-in-water health risks to be significantly underestimated, especially for unusual situations of “worst case” individual exposure to highly contaminated water.

Levine, R.L., Journal of Environmental Health, November 2012

Many public water systems in the U.S. are unsafe because the communities cannot afford to comply with the current 10 parts per billion (ppb) federal arsenic standard for drinking water. Communities unable to afford improvements remain vulnerable to adverse health effects associated with higher levels of arsenic exposure. Scientific and bipartisan political consensus exists that the arsenic standard should not be less stringent than 10 ppb, and new data suggest additional adverse health effects related to arsenic exposure through drinking water. Congress has failed to reauthorize the Drinking Water State Revolving Fund program to provide reliable funding to promote compliance and reduce the risk of adverse health effects. Congress’s recent ad hoc appropriations do not allow long-term planning and ongoing monitoring and maintenance. Investing in water infrastructure will lower health care costs and create American jobs. Delaying necessary upgrades will only increase the costs of improvements over time.

Collier, S.A., et al., Epidemiology and Infection, November 2012

Despite US sanitation advancements, millions of waterborne disease cases occur annually, although the precise burden of disease is not well quantified. Estimating the direct healthcare cost of specific infections would be useful in prioritizing waterborne disease prevention activities. Hospitalization and outpatient visit costs per case and total US hospitalization costs for ten waterborne diseases were calculated using large healthcare claims and hospital discharge databases. The five primarily waterborne diseases in this analysis (giardiasis, cryptosporidiosis, Legionnaires’ disease, otitis externa, and non-tuberculous mycobacterial infection) were responsible for over 40 000 hospitalizations at a cost of $970 million per year, including at least $430 million in hospitalization costs for Medicaid and Medicare patients. An additional 50 000 hospitalizations for campylobacteriosis, salmonellosis, shigellosis, haemolytic uraemic syndrome, and toxoplasmosis cost $860 million annually ($390 million in payments for Medicaid and Medicare patients), a portion of which can be assumed to be due to waterborne transmission.

Lee, C., et al., Applied and Environmental Microbiology, September 2012

The genus Arcobacter has been associated with human illness and fecal contamination by humans and animals. To better characterize the health risk posed by this emerging waterborne pathogen, we investigated the occurrence of Arcobacter spp. in Lake Erie beach waters. During the summer of 2010, water samples were collected 35 times from the Euclid, Villa Angela, and Headlands (East and West) beaches, located along Ohio’s Lake Erie coast. After sample concentration, Arcobacter was quantified by real-time PCR targeting the Arcobacter 23S rRNA gene. Other fecal genetic markers (Bacteroides 16S rRNA gene [HuBac], Escherichia coli uidA gene, Enterococcus 23S rRNA gene, and tetracycline resistance genes) were also assessed. Arcobacter was detected frequently at all beaches, and both the occurrence and densities of Arcobacter spp. were higher at the Euclid and Villa Angela beaches (with higher levels of fecal contamination) than at the East and West Headlands beaches. The Arcobacter density in Lake Erie beach water was significantly correlated with the human-specific fecal marker HuBac according to Spearman’s correlation analysis (r = 0.592; P < 0.001). Phylogenetic analysis demonstrated that most of the identified Arcobacter sequences were closely related to Arcobacter cryaerophilus, which is known to cause gastrointestinal diseases in humans. Since human-pathogenic Arcobacter spp. are linked to human-associated fecal sources, it is important to identify and manage the human-associated contamination sources for the prevention of Arcobacter-associated public health risks at Lake Erie beaches.

Bischoff, W.E., MD, PhD, et al., American Journal of Public Health, August 2012

The purpose of this study was to assess water quality in migrant farmworker camps in North Carolina and determine associations of water quality with migrant farmworker housing characteristics. Researchers collected data from 181 farmworker camps in eastern North Carolina during the 2010 agricultural season. Water samples were tested using the Total Coliform Rule (TCR) and housing characteristics were assessed using North Carolina Department of Labor standards. A total of 61 (34%) of 181 camps failed the TCR. Total coliform bacteria were found in all 61 camps, with Escherichia coli also being detected in 2. Water quality was not associated with farmworker housing characteristics or with access to registered public water supplies. Multiple official violations of water quality standards had been reported for the registered public water supplies. They concluded that water supplied to farmworker camps often does not comply with current standards and poses a great risk to the physical health of farmworkers and surrounding communities. Expansion of water monitoring to more camps and changes to the regulations such as testing during occupancy and stronger enforcement are needed to secure water safety.

Toccalino, P.L., Norman, J.E., Scott, J.C., Science of The Total Environment, August 2012

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources.

Lambertini, E., et al., Environmental Science and Technology, July 2012

Acute gastrointestinal illness (AGI) resulting from pathogens directly entering the piping of drinking water distribution systems is insufficiently understood. Here, we estimate AGI incidence from virus intrusions into the distribution systems of 14 nondisinfecting, groundwater-source, community water systems. Water samples for virus quantification were collected monthly at wells and households during four 12-week periods in 2006–2007. Ultraviolet (UV) disinfection was installed on the communities’ wellheads during one study year; UV was absent the other year. UV was intended to eliminate virus contributions from the wells and without residual disinfectant present in these systems, any increase in virus concentration downstream at household taps represented virus contributions from the distribution system (Approach 1). During no-UV periods, distribution system viruses were estimated by the difference between well water and household tap virus concentrations (Approach 2). For both approaches, a Monte Carlo risk assessment framework was used to estimate AGI risk from distribution systems using study-specific exposure–response relationships. Depending on the exposure–response relationship selected, AGI risk from the distribution systems was 0.0180–0.0661 and 0.001–0.1047 episodes/person-year estimated by Approaches 1 and 2, respectively. These values represented 0.1–4.9% of AGI risk from all exposure routes, and 1.6–67.8% of risk related to drinking water exposure. Virus intrusions into nondisinfected drinking water distribution systems can contribute to sporadic AGI.

Sales-Ortells, H., Medema, G., Environmental Science and Technology, April 2012

A screening-level risk assessment of Q fever transmission through drinking water produced from groundwater in the vicinity of infected goat barnyards that employed aeration of the water was performed. Quantitative data from scientific literature were collected and a Quantitative Microbial Risk Assessment approach was followed. An exposure model was developed to calculate the dose to which consumers of aerated groundwater are exposed through aerosols inhalation during showering. The exposure assessment and hazard characterization were integrated in a screening-level risk characterization using a dose-response model for inhalation to determine the risk of Q fever through tap water. A nominal range sensitivity analysis was performed. The estimated risk of disease was lower than 10(-4) per person per year (pppy), hence the risk of transmission of C. burnetii through inhalation of drinking water aerosols is very low. The sensitivity analysis shows that the most uncertain parameters are the aeration process, the transport of C. burnetii in bioaerosols via the air, the aerosolization of C. burnetii in the shower, and the air filtration efficiency. The risk was compared to direct airborne exposure of persons in the vicinity of infected goat farms; the relative risk of exposure through inhalation of drinking water aerosols was 0.002%.

Reynolds, K.A., MSPH, Ph.D., Water Conditioning & Purification, March 2012

Microbial threats to water quality continue to emerge; however, technologies for monitoring, treating and controlling emerging waterborne pathogens are also evolving. Understanding the range of factors that lead to the contamination of water are important for developing appropriate tools to manage human health risks.

Dorevitch, S., et al., Environmental Health Perspectives, February 2012

Wastewater-impacted waters that do not support swimming are often used for boating, canoeing, fishing, kayaking, and rowing. Little is known about the health risks of these limited-contact water recreation activities. We evaluated the incidence of illness, severity of illness, associations between water exposure and illness, and risk of illness attributable to limited-contact water recreation on waters dominated by wastewater effluent and on waters approved for general use recreation (such as swimming). The Chicago Health, Environmental Exposure, and Recreation Study was a prospective cohort study that evaluated five health outcomes among three groups of people: those who engaged in limited-contact water recreation on effluent-dominated waters, those who engaged in limited-contact recreation on general-use waters, and those who engaged in non–water recreation. Data analysis included survival analysis, logistic regression, and estimates of risk for counterfactual exposure scenarios using G-computation. Telephone follow-up data were available for 11,297 participants. With non–water recreation as the reference group, we found that limited-contact water recreation was associated with the development of acute gastrointestinal illness in the first 3 days after water recreation at both effluent-dominated waters [adjusted odds ratio (AOR) 1.46; 95% confidence interval (CI): 1.08, 1.96] and general-use waters (1.50; 95% CI: 1.09, 2.07). For every 1,000 recreators, 13.7 (95% CI: 3.1, 24.9) and 15.1 (95% CI: 2.6, 25.7) cases of gastrointestinal illness were attributable to limited-contact recreation at effluent-dominated waters and general-use waters, respectively. Eye symptoms were associated with use of effluent-dominated waters only (AOR 1.50; 95% CI: 1.10, 2.06). Among water recreators, our results indicate that illness was associated with the amount of water exposure. Limited-contact recreation, both on effluent-dominated waters and on waters designated for general use, was associated with an elevated risk of gastrointestinal illness.

U.S. Environmental Protection Agency, February 2012

This handbook is intended to provide information about how to enhance current planning processes by building in sustainability considerations. It is designed to be useful for various types and scales of planning efforts, such as: Long-range integrated water resource planning, Strategic planning, Capital planning, System-wide planning to meet regulatory requirements (e.g., combined sewer overflow upgrades and new stormwater permitting requirements), Specific infrastructure project planning (e.g., for repair, rehabilitation, or replacement of specific infrastructure)

Rinsky, J.L., et al., Public Health Reports, January/February 2012

Approximately 13% of all births occur prior to 37 weeks gestation in the U.S. Some established risk factors exist for preterm birth, but the etiology remains largely unknown. Recent studies have suggested an association with environmental exposures. We examined the relationship between preterm birth and exposure to a commonly used herbicide, atrazine, in drinking water. We reviewed Kentucky birth certificate data for 2004-2006 to collect duration of pregnancy and other individual-level covariates. We assessed existing data sources for atrazine levels in public drinking water for the years 2000-2008, classifying maternal county of residence into three atrazine exposure groups. We used logistic regression to analyze the relationship between atrazine exposure and preterm birth, controlling for maternal age, race/ethnicity, education, smoking, and prenatal care. An increase in the odds of preterm birth was found for women residing in the counties included in the highest atrazine exposure group compared with women residing in counties in the lowest exposure group, while controlling for covariates. Analyses using the three exposure assessment approaches produced odds ratios ranging from 1.20 (95% confidence interval [CI] 1.14, 1.27) to 1.26 (95% CI 1.19, 1.32), for the highest compared with the lowest exposure group. Suboptimal characterization of environmental exposure and variables of interest limited the analytical options of this study. Still, our findings suggest a positive association between atrazine and preterm birth, and illustrate the need for an improved assessment of environmental exposures to accurately address this important public health issue.

Water Research Foundation, January 2012

In 2007, a group of source water protection experts met, under the auspices of the Water Research Foundation and the Water Environment Research Foundation, to develop a research agenda that would ultimately provide information to help drinking water suppliers design and implement effective source water protection programs. A key result of that effort identified the need for a national vision and roadmap that would guide U.S. water utilities and supporting groups with a unified strategy for coherent, consistent, cost-effective, and socially-acceptable source water protection programs. This brief document presents the vision and roadmap and focuses on how to move forward on source water protection. The roadmap is intended to serve as a feasible, focused path toward promoting source water protection for U.S. drinking water utilities. It is not intended to serve as an official directive, but rather is a collection of observations and recommendations organized to form a path to achieving the vision. The companion document Developing a Vision and Roadmap for Drinking Water Source Protection comprehensively covers the project team’s findings regarding the various building blocks to make source water protection a reality. That document includes an annotated bibliography of source water protection resources, a summation of a literature review, and helpful water utility case studies. Both documents are meant to be used in concert to help water utilities move forward with their source water protection efforts and proactively improve and/or maintain the quality of their drinking water sources. Source water protection has been discussed and promoted in an ad hoc fashion by different organizations at the national, regional, state, and local levels. It is essential to increase the awareness of source water protection at the national level. Education of decision makers, utility managers, stakeholders, and the general public should be the first step in moving source water protection up a path to success. Leadership is needed to make this a national priority. In order to ensure the various actions recommended in the roadmap can be carried out, it is recommended that both a top-down and a bottom-up approach be taken. A top-down approach would establish a flexible framework to guide local entities (e.g., water systems, watershed organizations, and regional planning agencies) to work together to protect source water. Due to the variability of source waters and the areas from which they are derived, along with technical, social, political, financial, and regulatory differences across jurisdictions, it is unlikely that two source water protection programs would be the same. A bottom-up approach is therefore also needed, which would use local information and broad stakeholder involvement to produce a “tailored” source water protection program that addresses unique issues at the local level.

Erdem, Y.K., Furkan, A., International Journal of Applied Science and Technology, January 2012

Bisphenol-A is a widely used chemical in the structure of epoxy resins, polycarbonate packages, lacquer of metal food packages all over the world. Its weak estrogenic character and possible health effects are well known. For this reason the usage of the Bisphenol-A in food packages is limited and it’s daily intake by human is restrictly under control. The declaration of specific migration limit is 0.6 ppm, the tolerable daily intake is 0.05mg/kg body weight per day by EFSA and other authorities. The EFSA and others prevent the manufacturing and using of Bisphenol-A in baby bottles in 2010. In Turkey, the 70% of the population are living in 5 metropolitan cities and the drinking water consumption is mostly supplied by packaged drinking water industry. The household and bulk usage is covered by natural spring and natural mineral water packaged in 19 liters polycarbonate carboys. That’s why the possible migration of Bisphenol-A in drinking water packaged in polycarbonate carboys was decided to investigate. First of all, a screening test was carried out in the samples supplied by two main cities. And then 5 different trade mark packaged water samples was stored at 4, 25, and 35oC for 60 days and Bisphenol-A content was determined in given intervals. It is found that the BPA migration was detected at least 450 times lower than the specific migration limit of EFSA during 60 days storage at these conditions.

Cotruvo, J.A., et al., e-Journal AWWA, November 2010

This article advocates for a revised risk assessment for bromate to reflect presystemic chemistry not usually considered when low-dose risks are calculated from high-dose toxicology data. Because of high acidity and the presence of reducing agents, presystemic decomposition of bromate can begin in the stomach, which should contribute to lower-than- expected doses to target organs. In this research, bromate decomposition kinetics with simulated stomach/gastric juice were studied to determine the risk of environmentally relevant exposure to bromate. The current work is the first step in a series of studies that the authors are conducting to better estimate the hypothetical low-dose risks to humans from drinking water ingestion and thus arrive at more appropriate maximum contaminant levels (MCLs). It is the authors’ belief that additional kinetics and metabolism research will demonstrate that the human risk from ingestion of compounds in drinking water is less than originally believed and will lead to MCLs and MCL goals that are more scientifically based.

Gustavo Saposnik, MD, MSc, FAHA, Stroke, October 2010

In the present issue of Stroke, the authors investigate the association between low-level arsenic exposure in drinking water and the ischemic stroke admissions in Michigan. They found that even low exposure to arsenic is associated with an increased incident risk of stroke (relative risk, 1.03; 95% CI, 1.01 to 1.05 per µg/L increase in arsenic concentration). The authors also compared whether that exposure was associated with other nonvascular conditions (hernia, duodenal ulcer) not expected to increase their risk. Comparing zip codes in Genesee County at the 90th percentile of arsenic levels (21.6 µg/L) with those at the 10th percentile (0.30 µg/L), there was a 91% increase in risk of stroke admission (relative risk, 1.91; 95% CI, 1.27 to 2.88). The results were consistent in showing an increased risk for stroke, but not for other control medical conditions (hernia and duodenal ulcer). Moreover, they found a graded effect: a higher incident risk among those individuals exposed to higher water concentrations of arsenic (Figure 2).

Water Technology, August 2010

A common theme we see on a daily basis relates to drinking water infrastructure. We track news throughout the world that impacts the drinking water industry, and one of the most frequent things we see are notices from agencies and organizations about the need for communities to boil water in order to combat possible contamination. In some parts of the world, boiling water is the norm due to water supply issues. Often, these areas may be limited in their ability to develop economically, as clean water is such an integral part of daily life. It is in the developed world, however, where we have been seeing a large increase in the number of such notices.

www.nrdc.org, July 2010

Climate change will have a significant impact on the sustainability of water supplies in the coming decades. A new analysis, performed by consulting firm Tetra Tech for the Natural Resources Defense Council (NRDC), examined the effects of global warming on water supply and demand in the contiguous United States. The study found that more than 1,100 counties— one-third of all counties in the lower 48—will face higher risks of water shortages by mid-century as the result of global warming. More than 400 of these counties will face extremely high risks of water shortages.

Hwang, B.-F., Jaakkola, J., Guo, H.-R., Environmental Health,  June 2008

Recent findings suggest that exposure to disinfection by-products may increase the risk of birth defects. Previous studies have focused mainly on birth defects in general or groups of defects. The objective of the present study was to assess the effect of water disinfection by-products on the risk of most common specific birth defects. We conducted a population-based cross-sectional study of 396,049 Taiwanese births in 2001-2003 using information from the Birth Registry and Waterworks Registry. We compared the risk of eleven most common specific defects in four disinfection by-product exposure categories based on the levels of total trihalomethanes (TTHMs) representing high (TTHMs 20+ ug/L), medium (TTHMs 10-19 ug/L), low exposure (TTHMs 5-9 ug/L), and 0-4 ug/L as the reference category. In addition, we conducted a meta-analysis of the results from the present and previous studies focusing on the same birth defects.

Luben, T.J., Nuckols, J.R., Mosley, B.S., Hobbs, C., Reif, J.S., Occupational and Environmental Medicine, June 2008

The use of chlorine for water disinfection results in the formation of numerous contaminants called disinfection by-products (DBPs), which may be associated with birth defects, including urinary tract defects. We used Arkansas birth records (1998-2002) to conduct a population-based case-control study investigating the relationship between hypospadias and two classes of DBPs, trihalomethanes (THM) and haloacetic acids (HAA). We utilised monitoring data, spline regression and geographical information systems (GIS) to link daily concentrations of these DBPs from 263 water utilities to 320 cases and 614 controls. We calculated ORs for hypospadias and exposure to DBPs between 6 and 16 weeks’ gestation, and conducted subset analyses for exposure from ingestion, and metrics incorporating consumption, showering and bathing. We found no increase in risk when women in the highest tertiles of exposure were compared to those in the lowest for any DBP. When ingestion alone was used to assess exposure among a subset of 40 cases and 243 controls, the intermediate tertiles of exposure to total THM and the five most common HAA had ORs of 2.11 (95% CI 0.89 to 5.00) and 2.45 (95% CI 1.06 to 5.67), respectively, compared to women with no exposure. When exposure to total THM from consumption, showering and bathing exposures was evaluated, we found an OR of 1.96 (95% CI 0.65 to 6.42) for the highest tertile of exposure and weak evidence of a dose-response relationship. Our results provide little evidence for a positive relationship between DBP exposure during gestation and an increased risk of hypospadias but emphasize the necessity of including individual-level data when assessing exposure to DBPs.

Zhao, Y.-Y., et al., Environmental Science & Technology, May 2008

Formation of nine N-nitrosamines has been investigated when seven different source waters representing various qualities were each treated with eleven bench-scale disinfection processes, without addition of nitrosamine precursors. These disinfection treatments included chlorine (OCl-) chloramine (NH2Cl), chlorine dioxide (ClO2), ozone (O3), ultraviolet (UV), advanced oxidation processes (AOP), and combinations. The total organic carbon (TOC) of the seven source waters ranged from 2 to 24 mg L-1. The disinfected water samples and the untreated source waters were analyzed for nine nitrosamines using a solid phase extraction and liquid chromatography-tandem mass spectrometry method. Prior to any treatment, N-nitrosodimethylamine (NDMA) was detected ranging from 0 to 53 ng L-1 in six of the seven source waters, and its concentrations increased in the disinfected water samples (0 – 118 ng L-1). N-nitrosodiethylamine (NDEA), N-nitrosomorpholine (NMor), and N-nitrosodiphenylamine (NDPhA) were also identified in some of the disinfected water samples. NDPhA (0.2- 0.6 ng L-1) was formed after disinfection with OCl-, NH2Cl, O3, and MPUV/OCl-. NMEA was produced with OCl- and MPUV/OCl-, and NMor formation was associated with O3. In addition, UV treatment alone degraded NDMA; however, UV/OCl- and AOP/OCl- treatments produced higher amounts of NDMA compared to UV and AOP alone, respectively. These results suggest that UV degradation or AOP oxidation treatment may provide a source of NDMA precursors. This study demonstrates that environmental concentrations and mixtures of unknown nitrosamine precursors in source waters can form NDMA and other nitrosamines.

Schmidt, C.K., Brauch, H.-J., Environmental Science & Technology, April 2008

Application and microbial degradation of the fungicide tolylfluanide gives rise to a new decomposition product named N,N-dimethylsulfamide (DMS). In Germany, DMS was found in groundwaters and surface waters with typical concentrations in the range of 100-1000 ng/L and 50-90 ng/L, respectively. Laboratory-scale and field investigations concerning its fate during drinking water treatment showed that DMS cannot be removed via riverbank filtration, activated carbon filtration, flocculation, and oxidation or disinfection procedures based on hydrogen peroxide, potassium permanganate, chlorine dioxide, or UV irradiation. Even nanofiltration does not provide a sufficient removal efficiency. During ozonation about 30-50% of DMS are converted to the carcinogenic N-nitrosodimethylamine (NDMA). The NDMA being formed is biodegradable and can at least partially be removed by subsequent biologically active drinking water treatment steps including sand or activated carbon filtration. Disinfection with hypochlorous acid converts DMS to so far unknown degradation products but not to NDMA or 1,1-dimethylhydrazine (UDMH).

Chisholm, K., et al., Environmental Health Perspective, April 2008

By international standards, water supplies in Perth, Western Australia, contain high trihalomethane (THM) levels, particularly the brominated forms. Geographic variability in these levels provided an opportunity to examine cross-city spatial relationships between THM exposure and rates of birth defects (BDs).Our goal was to examine BD rates by exposure to THMs with a highly brominated fraction in metropolitan locations in Perth, Western Australia. We collected water samples from 47 separate locations and analyzed them for total and individual THM concentrations (micrograms per liter), including separation into brominated forms. We classified collection areas by total THM (TTHM) concentration: low (< 60 microg/L), medium (> 60 to < 130 microg/L), and high (> or = 130 microg/L). We also obtained deidentified registry-based data on total births and BDs (2000-2004 inclusive) from post codes corresponding to water sample collection sites and used binomial logistic regression to compare the frequency of BDs aggregately and separately for the TTHM exposure groups, adjusting for maternal age and socioeconomic status. Total THMs ranged from 36 to 190 microg/L. A high proportion of the THMs were brominated (on average, 92%). Women living in high-TTHM areas showed an increased risk of any BD [odds ratio (OR) = 1.22; 95% confidence interval (CI), 1.01-1.48] and for the major category of any cardiovascular BD (OR = 1.62; 95% CI, 1.04-2.51), compared with women living in low-TTHM areas. Brominated forms constituted the significant fraction of THMs in all areas. Small but statistically significant increases in risks of BDs were associated with residence in areas with high THMs.

U.S. Environmental Protection Agency, March, 2008

There are approximately 156,000 public drinking water systems in the United States. Each of these systems regularly supplies drinking water to at least 25 people or 15 service connections. Beyond their common purpose, the 156,000 systems vary widely. The following tables group water systems into categories that show their similarities and differences. For example, the first table shows that most people in the US (286 million) get their water from a community water system. There are approximately 52,000 community water systems, but just eight percent of those systems (4,048) serve 82 percent of the people. The second table shows that more water systems have groundwater than surface water as a source–but more people drink from a surface water system. Other tables break down these national numbers by state, territory, and EPA region.

This package also contains figures on the types and locations of underground injection control wells. EPA and states regulate the placement and operation of these wells to ensure that they do not threaten underground sources of drinking water. The underground injection control program statistics are based on separate reporting from the states to EPA. The drinking water system statistics on the following pages are taken from the Safe Drinking Water Information System/Federal version (SDWIS/Fed). SDWIS/Fed is the U.S. Environmental Protection Agency’s official record of public drinking water systems, their violations of state and EPA regulations, and enforcement actions taken by EPA or states as a result of those violations. EPA maintains the database using information collected and submitted by the states. Notice: Compliance statistics are based on violations reported by states to the EPA Safe Drinking Water Information System. EPA is aware of inaccuracies and underreporting of some data in this system. We are working with the states to improve the quality of the data. Read an analysis of SDWIS/Fed data quality and get more information and additional drinking water data tables.

Hamidin, N., Yu, Q.J., Connell, D.W., Water Research, March 2008

The presence of chlorinated disinfection by-products (DBPs) in drinking water is a public health issue, due to their possible adverse health effects on humans. To gauge the risk of chlorinated DBPs on human health, a risk assessment of chloroform (trichloromethane (TCM)), bromodichloromethane (BDCM), dibromochloromethane (DBCM), bromoform (tribromomethane (TBM)), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in drinking water was carried out using probabilistic techniques. Literature data on exposure concentrations from more than 15 different countries and adverse health effects on test animals as well as human epidemiological studies were used. The risk assessment showed no overlap between the highest human exposure dose (EXP(D)) and the lowest human equivalent dose (HED) from animal test data, for TCM, BDCM, DBCM, TBM, DCAA and TCAA. All the HED values were approximately 10(4)-10(5) times higher than the 95th percentiles of EXP(D). However, from the human epidemiology data, there was a positive overlap between the highest EXP(D) and the lifetime average daily doses (LADD(H)) for TCM, BDCM, DCAA and TCAA. This suggests that there are possible adverse health risks such as a small increased incidence of cancers in males and developmental effects on infants. However, the epidemiological data comprised several risk factors and exposure classification levels which may affect the overall results.

Maclehose, R.F., Savitz, D.A., Herring, A.H., Hartmann, K.E., Singer, P.C., Weinberg, H.S., Epidemiology, March 2008

Laboratory evidence suggests tap water disinfection by-products (DBPs) could have an effect very early in pregnancy, typically before clinical detectability. Undetected early losses would be expected to increase the reported number of cycles to clinical pregnancy. We investigated the association between specific DBPs (trihalomethanes, haloacetic acids, brominated-trihalomethanes, brominated-haloacetic acids, total organic halides, and bromodichloromethane) and time to pregnancy among women who enrolled in a study of drinking water and reproductive outcomes. We quantified exposure to DBPs through concentrations in tap water, quantity ingested through drinking, quantity inhaled or absorbed while showering or bathing, and total integrated exposure. The effect of DBPs on time to pregnancy was estimated using a discrete time hazard model. Overall, we found no evidence of an increased time to pregnancy among women who were exposed to higher levels of DBPs. A modestly decreased time to pregnancy (ie, increased fecundability) was seen among those exposed to the highest level of ingested DBPs, but not for tap water concentration, the amount absorbed while showering or bathing, or the integrated exposure. Our findings extend those of a recently published study suggesting a lack of association between DBPs and pregnancy loss.

Reynolds, K.A., Mena, K.D., Gerba, C.P., Reviews of Environmental Contamination & Toxicology, January 2008

Outbreaks of disease attributable to drinking water are not common in the U.S., but they do still occur and can lead to serious acute, chronic, or sometimes fatal health consequences, particularly in sensitive and immunocompromised populations. From 1971 to 2002, there were 764 documented waterborne outbreaks associated with drinking water, resulting in 575,457 cases of illness and 79 deaths (Blackburn et al. 2004; Calderon 2004); however, the true impact of disease is estimated to be much higher. If properly applied, current protocols in municipal water treatment are effective at eliminating pathogens from water. However, inadequate, interrupted, or intermittent treatment has repeatedly been associated with waterborne disease outbreaks. Contamination is not evenly distributed but rather affected by the number of pathogens in the source water, the age of the distribution system, the quality of the delivered water, and climatic events that can tax treatment plant operations. Private water supplies are not regulated by the USEPA and are generally not treated or monitored, although very few of the municipal systems involved in documented outbreaks exceeded the USEPA’s total coliform standard in the preceding 12 mon (Craun et al. 2002). We provide here estimates of waterborne infection and illness risks in the U.S. based on the total number of water systems, source water type, and total populations exposed. Furthermore, we evaluated all possible illnesses associated with the microbial infection and not just gastroenteritis. Our results indicate that 10.7 M infections/yr and 5.4 M illnesses/yr occur in populations served by community groundwater systems; 2.2 M infections/yr and 1.1 M illnesses/yr occur in noncommunity groundwater systems; and 26.0 M infections/yr and 13.0 M illnesses/yr occur in municipal surface water systems. The total estimated number of waterborne illnesses/yr in the U.S. is therefore estimated to be 19.5 M/yr. Others have recently estimated waterborne illness rates of 12M cases/yr (Colford et al. 2006) and 16 M cases/yr (Messner et al. 2006), yet our estimate considers all health outcomes associated with exposure to pathogens in drinking water rather than only gastrointestinal illness. Drinking water outbreaks exemplify known breaches in municipal water treatment and distribution processes and the failure of regulatory requirements to ensure water that is free of human pathogens. Water purification technologies applied at the point-of-use (POU) can be effective for limiting the effects of source water contamination, treatment plant inadequacies, minor intrusions in the distribution system, or deliberate posttreatment acts (i.e., bioterrorism). Epidemiological studies are conflicting on the benefits of POU water treatment. One prospective intervention study found that consumers of reverse-osmosis (POU) filtered water had 20%-35% less gastrointestinal illnesses than those consuming regular tap water, with an excess of 14% of illness due to contaminants introduced in the distribution system (Payment 1991, 1997). Two other studies using randomized, blinded, controlled trials determined that the risks were equal among groups supplied with POU-treated water compared to untreated tap water (Hellard et al. 2001; Colford et al. 2003). For immunocompromised populations, POU water treatment devices are recommended by the CDC and USEPA as one treatment option for reducing risks of Cryptosporidium and other types of infectious agents transmitted by drinking water. Other populations, including those experiencing “normal” life stages such as pregnancy, or those very young or very old, might also benefit from the utilization of additional water treatment options beyond the current multibarrier approach of municipal water treatment.

Fong, T.-T., et al., Environmental Health Perspectives, June 2007

A groundwater-associated outbreak affected approximately 1,450 residents and visitors of South Bass Island, Ohio, between July and September 2004. To examine the microbiological quality of groundwater wells located on South Bass Island, we sampled 16 wells that provide potable water to public water systems 15–21 September 2004. We tested groundwater wells for fecal indicators, enteric viruses and bacteria, and protozoa (Cryptosporidium and Giardia). The hydrodynamics of Lake Erie were examined to explore the possible surface water–groundwater interactions. All wells were positive for both total coliform and Escherichia coli. Seven wells tested positive for enterococci and Arcobacter (an emerging bacterial pathogen), and F+-specific coliphage was present in four wells. Three wells were positive for all three bacterial indicators, coliphages, and Arcobacter; adenovirus DNA was recovered from two of these wells. We found a cluster of the most contaminated wells at the southeast side of the island. Conclusions: Massive groundwater contamination on the island was likely caused by transport of microbiological contaminants from wastewater treatment facilities and septic tanks to the lake and the subsurface, after extreme precipitation events in May–July 2004. This likely raised the water table, saturated the subsurface, and along with very strong Lake Erie currents on 24 July, forced a surge in water levels and rapid surface water–groundwater interchange throughout the island. Landsat images showed massive influx of organic material and turbidity surrounding the island before the peak of the outbreak. These combinations of factors and information can be used to examine vulnerabilities in other coastal systems. Both wastewater and drinking water issues are now being addressed by the Ohio Environmental Protection Agency and the Ohio Department of Health.

U.S. Environmental Protection Agency, April 2007

Total coliforms have long been used in drinking water regulations as an indicator of the adequacy of water treatment and the integrity of the distribution system. Total coliforms are a group of closely related bacteria that are generally harmless. In drinking water systems, total coliforms react to treatment in a manner similar to most bacterial pathogens and many viral pathogens. Thus, the presence of total coliforms in the distribution system can indicate that the system in also vulnerable to the presence of pathogens in the system. (EPA, June 2001, page 7) Total coliforms are the indicators used in the existing Total Coliform Rule (TCR). EPA is undertaking “a rulemaking process to initiate possible revisions to the TCR. As part of this process, EPA believes it may be appropriate to include this rulemaking in a wider effort to review and address broader issues associated with drinking water distribution systems.” (see Federal Register 68 FR 19030 and 68 FR 42907). Since the promulgation of the TCR, EPA has received stakeholder feedback suggesting modifications to the TCR to reduce the implementation burden. The purpose of this paper is to provide information on the number and frequency of violations of the TCR and to further characterize the frequency with which different types and sizes of systems incur violations. Although EPA explores some statistical testing in this paper, the paper concentrates on presenting the data, as it is, in SDWIS/FED. Information on these frequencies will be useful in supporting several EPA initiatives, particularly the effort to review and possibly revise the TCR. This paper has been undertaken as part of the review of the TCR.

DeMarini, D.M., et al., Environmental Science & Technology, January 2007

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.

Messner, M., et al., Journal of Water and Health,  04.suppl 2, July 2006

In this paper, the US Environmental Protection Agency (EPA) presents an approach and a national estimate of drinking water related endemic acute gastrointestinal illness (AGI) that uses information from epidemiologic studies. There have been a limited number of epidemiologic studies that have measured waterborne disease occurrence in the United States. For this analysis, we assume that certain unknown incidence of AGI in each public drinking water system is due to drinking water and that a statistical distribution of the different incidence rates for the population served by each system can be estimated to inform a mean national estimate of AGI illness due to drinking water. Data from public water systems suggest that the incidence rate of AGI due to drinking water may vary by several orders of magnitude. In addition, data from epidemiologic studies show AGI incidence due to drinking water ranging from essentially none (or less than the study detection level) to a rate of 0.26 cases per person-year. Considering these two perspectives collectively, and associated uncertainties, EPA has developed an analytical approach and model for generating a national estimate of annual AGI illness due to drinking water. EPA developed a national estimate of waterborne disease to address, in part, the 1996 Safe Drinking Water Act Amendments. The national estimate uses best available science, but also recognizes gaps in the data to support some of the model assumptions and uncertainties in the estimate. Based on the model presented, EPA estimates a mean incidence of AGI attributable to drinking water of 0.06 cases per year (with a 95% credible interval of 0.02–0.12). The mean estimate represents approximately 8.5% of cases of AGI illness due to all causes among the population served by community water systems. The estimated incidence translates to 16.4 million cases/year among the same population. The estimate illustrates the potential usefulness and challenges of the approach, and provides a focus for discussions of data needs and future study designs. Areas of major uncertainty that currently limit the usefulness of the approach are discussed in the context of the estimate analysis.

Reynolds, K.A., Water Conditioning & Purification, July 2006

As water treatment professionals, maybe you’ve been alerted to news stories suggesting a connection between tap water consumption and bladder cancer, but are these headlines true or just media hype? Although the most recently reported association of tap water consumption with bladder cancer is indeed based on numerous epidemiological studies with an international scope, all scientific research must be carefully evaluated; not just in terms of the data found, but also for the information possibly missed. The study that has everyone talking again about tap water consumption and its relationship to bladder cancer was published in the International Journal of Cancer (April 2006). Looking at data from six epidemiological studies, conducted in five countries worldwide (Canada, Finland, France, Italy and two in the United States), a significant association was found between tap water consumption and bladder cancer among men. The risk increased with consumption of greater volumes, suggesting that carcinogenic chemicals in tap water were responsible for the increased risk. While the information presented appears to be sound, it is important to understand the limitations of the study approach so that the data can be appropriately analyzed with respect to public health significance.

Despite a gender bias and inconsistent reports in the historical literature, this study seems to have sturdy legs to stand on or to at least justify continued research. As mentioned earlier, epidemiology is not a very sensitive science and is complicated by unknown confounders. In addition, this study provides no evidence as to what specific factors related to tap water are causing an increase in cancer, where other drinking water sources (i.e., bottled water) show no association. Water is clearly a heterogeneous mix of contaminants, with vast geographical and temporal fluctuations. Little is known about the combined effects of multiple contaminants found in drinking water, thus a study of single contaminants and their association with cancer risks would not provide a complete picture of overall exposures.

U.S. Geological Survey, June 2006

When volatile organic compounds (VOCs) are detected in samples from drinking-water supply wells, it is important to understand what these results may mean to human health. As a first step toward understanding VOC occurrence in the context of human health, a screening-level assessment was conducted by comparing VOC concentrations to human-health benchmarks. One sample from each of 3,497 domestic and public wells was analyzed for 55 VOCs; samples were collected prior to treatment or blending. At least one VOC was detected in 623 well samples (about 18 percent of all well samples) at a threshold of 0.2 part per billion. Eight of the 55 VOCs had concentrations greater than human-health benchmarks in 45 well samples (about 1 percent of all well samples); these concentrations may be of potential human-health concern if the water were to be ingested without treatment for many years. VOC concentrations were less than human-health benchmarks in most well samples with VOC detections, indicating that adverse effects are unlikely to occur, even if water with such concentrations were to be ingested over a lifetime. Seventeen VOCs may warrant further investigation because their concentrations were greater than, or approached, human-health benchmarks.

Michael Messner, Susan Shaw, Stig Regli, Ken Rotert, Valerie Blank and Jeff Soller, Journal of Water and Health, 2006;04.suppl2:201-40

In this paper, the US Environmental Protection Agency (EPA) presents an approach and a national estimate of drinking water related endemic acute gastrointestinal illness (AGI) that uses information from epidemiologic studies. There have been a limited number of epidemiologic studies that have measured waterborne disease occurrence in the United States. For this analysis, we assume that certain unknown incidence of AGI in each public drinking water system is due to drinking water and that a statistical distribution of the different incidence rates for the population served by each system can be estimated to inform a mean national estimate of AGI illness due to drinking water. Data from public water systems suggest that the incidence rate of AGI due to drinking water may vary by several orders of magnitude. In addition, data from epidemiologic studies show AGI incidence due to drinking water ranging from essentially none (or less than the study detection level) to a rate of 0.26 cases per person-year. Considering these two perspectives collectively, and associated uncertainties, EPA has developed an analytical approach and model for generating a national estimate of annual AGI illness due to drinking water. EPA developed a national estimate of waterborne disease to address, in part, the 1996 Safe Drinking Water Act Amendments. The national estimate uses best available science, but also recognizes gaps in the data to support some of the model assumptions and uncertainties in the estimate. Based on the model presented, EPA estimates a mean incidence of AGI attributable to drinking water of 0.06 cases per year (with a 95% credible interval of 0.02–0.12). The mean estimate represents approximately 8.5% of cases of AGI illness due to all causes among the population served by community water systems. The estimated incidence translates to 16.4 million cases/year among the same population. The estimate illustrates the potential usefulness and challenges of the approach, and provides a focus for discussions of data needs and future study designs. Areas of major uncertainty that currently limit the usefulness of the approach are discussed in the context of the estimate analysis.

Quinones, O., Snyder, S.A., Cotruvo, J.A., Fisher, J.W., Toxicology, April 2006

Bull, R.J. and Cotruvo, J.A., Toxicology, April 2006

• Bromate;
• Research to improve risk assessment;
• Drinking water

Keith, J.D., Pacey, G.E., Cotruvo, J.A., Gordon,G., Toxicology, February 2006

This study was designed to identify and quantify the effects of reducing agents on the rate of bromate ion reduction in real and synthetic gastric juice. This could be the first element in the sequence of a pharmacokinetic description of the fate of bromate ion entering the organism, being metabolized, and subsequently being tracked through the system to the target cell or eliminated. Synthetic gastric juice containing H⁺ and Cl⁻ did exhibit reduced bromate ion levels, but at a rate that was too slow for a significant amount of bromate to be reduced under typical stomach retention time conditions. The reaction orders for Cl⁻ and H⁺ were 1.50 and 2.0, respectively. Addition of the reducing agents hydrogen sulfide (which was shown to be present and quantified in real gastric juice), glutathione, and/or cysteine increased the rate of bromate ion loss. All of the reactions showed significant pH effects. Half-lives as short as 2 min were measured for bromate ion reduction in 0.17 M H⁺ and Cl⁻ and 10⁻⁴ M H₂S. Therefore, the lifetime of bromate ion in solutions containing typical gastric juice concentrations of H⁺, Cl⁻, and H₂S is 20–30 min. This rate should result in as much as a 99% reduction of bromate ion during its residence in the stomach. Bromate ion reduction in real gastric juice occurred at a rapid rate. A comparison of real and synthetic gastric juice containing H⁺, Cl⁻, cysteine, glutathione, and hydrogen sulfide showed that the component most responsible for the considerable decrease of the concentration of bromate ion in the stomach is hydrogen sulfide.

• Bromate;
• Gastric juice;
• Ion chromatography;
• Hydrogen sulfide

Keith N. Eshelman, Ph.D. Associate Professor, University of Maryland, Center for Environmental Studies, May 2005

A comprehensive, quantitative survey of bottled water producers in the U.S. that reveals data collected on bottled water production, specifically production from ground water, the primary source of bottled water.Relative to other uses of ground water, bottled water production was found to be a de minimus user of ground water.