[Show abstract][Hide abstract] ABSTRACT: There is little published literature on the efficacy of strategies to reduce exposure to residential well water arsenic. The objectives of our study were to: 1) determine if water arsenic remained a significant exposure source in households using bottled water or point-of-use treatment systems; and 2) evaluate the major sources and routes of any remaining arsenic exposure. We conducted a cross-sectional study of 167 households in Maine using one of these two strategies to prevent exposure to arsenic. Most households included one adult and at least one child. Untreated well water arsenic concentrations ranged from <10μg/L to 640μg/L. Urine samples, water samples, daily diet and bathing diaries, and household dietary and water use habit surveys were collected. Generalized estimating equations were used to model the relationship between urinary arsenic and untreated well water arsenic concentration, while accounting for documented consumption of untreated water and dietary sources. If mitigation strategies were fully effective, there should be no relationship between urinary arsenic and well water arsenic. To the contrary, we found that untreated arsenic water concentration remained a significant (p≤0.001) predictor of urinary arsenic levels. When untreated water arsenic concentrations were <40μg/L, untreated water arsenic was no longer a significant predictor of urinary arsenic. Time spent bathing (alone or in combination with water arsenic concentration) was not associated with urinary arsenic. A predictive analysis of the average study participant suggested that when untreated water arsenic ranged from 100 to 500μg/L, elimination of any untreated water use would result in an 8%-32% reduction in urinary arsenic for young children, and a 14%-59% reduction for adults. These results demonstrate the importance of complying with a point-of-use or bottled water exposure reduction strategy. However, there remained unexplained, water-related routes of exposure.
No preview · Article · Feb 2016 · Science of The Total Environment
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Approximately 15% of the U.S. population relies on private domestic water sources for drinking water. These sources may be susceptible to more frequent contamination and higher contaminant levels than in community water supplies. Despite the significance of this threat, private water sources (mostly wells) are largely unregulated in the U.S. and monitoring is almost always the responsibility of the home owner. States vary considerably in the availability of, access to, and organization of private water source data. Several states that are part of the National Environmental Public Health Tracking (EPHT) program developed recommendations for measures of private water quality for specific contaminants of widespread concern (arsenic and nitrate). The purpose of this presentation is to report on the efforts of nine EPHT states to compile data sets on private well water quality and to create and display maps of vulnerable areas in their jurisdictions at meaningful geographic scales.
METHODS: Communication among the participating states was primarily via teleconferences, webinars and file sharing. Initially, the participating states assessed the availability, geographic coverage, time period and completeness of private water source data, and determined whether private well data could be summarized at county or sub-county geographic scales. States also considered use cases, potential data users, and existing EPHT portal mapping and graphics tools to inform the design of state-specific displays and accompanying messages.
RESULTS: States prepared data sets when possible, and some were able to create state-wide vulnerability maps based on existing private well water data. One state without access to actual well data used a modeled vulnerability map based on geologic characteristics and limited groundwater data. The presentation will show private well vulnerability maps for arsenic and nitrate from participating states. Limited user testing in some states helped to refine the content of maps and graphics for all participants. Some state participants were able to integrate private well information onto their existing EPHT portals together with appropriate public health messaging.
CONCLUSIONS: Participating states improved the availability and organization of private well water data. Some developed maps showing geographic variation in private well contaminant vulnerability, using consistent metrics, and to display maps and public health messages on EPHT portals. These efforts will assist public health practitioners at the state and local level to identify geographic areas of higher risk of contamination and to target outreach efforts to home owners to test and take action to reduce exposures to contaminants of concern.
[Show abstract][Hide abstract] ABSTRACT: Blood lead concentrations are higher in young children than in other age groups, whereas little is known regarding concentrations of other metals in young children. We measured the concentrations of a suite of metals in the blood of children 1-6 years of age, and assessed potential differences by age, season, or region of Maine. We used blood submitted to the Maine State Health and Environmental Testing Laboratory for blood lead analysis to determine the concentrations of arsenic (As), antimony (Sb), cadmium (Cd), manganese (Mn), mercury (Hg), selenium (Se), tin (Sn), and uranium (U) in 1350 children 1-6 years of age. The essential metals Mn and Se were detected in all samples, and As and Sb were detected in >90% of samples. Hg was detected in approximately 60% of samples. U and Cd were less often detected in blood samples, at approximately 30% and 10% of samples, respectively. Sn was not detected in any sample. Concentrations of As, Hg, and Se increased with age, whereas Sb decreased with age. Concentrations also varied by season and region for some though not all metals. Significant pairwise correlations were observed for a number of metals. Blood is a reasonable compartment for measurement of most of these metals in young children. The use of convenience samples provided a cost-effective mechanism for assessing exposure of young children in Maine.
No preview · Article · Nov 2010 · Journal of Exposure Science and Environmental Epidemiology