Private-well stewardship among a general population based sample of private well-owners

Individual and environmental correlates of tap water consumption among adolescents in Canada

The study objective was to identify correlates of tap water consumption among adolescents. French-speaking adolescents from the province of Québec (Canada) were recruited in person and online from March to July 2023 using diverse recruitment strategies. Water consumption was measured using the validated French version of a questionnaire specifically designed to measure adolescents' beverage intake. Participants answered an online survey on their attitude towards tap and bottled water which also measured individual and environmental factors that can influence tap water consumption. A total of 218 adolescents (14-17 years; 55.5% female) completed the survey. On average, 79.2% of adolescents' water intake came from tap and 33.5% of them consumed exclusively tap water. Thinking that bottled water is more convenient than tap water was a significant correlate of adolescents' tap water consumption (OR = 0.70; 95% CI: 0.51, 0.95; p = 0.0219). Adolescents who believed that bottled water is more convenient than tap water were less likely to consume exclusively tap water. Public health interventions aimed at promoting adolescents' tap water should strive to make tap water intake be perceived as convenient as bottled water, such as encouraging teenagers to always carry along a reusable water bottle, installing drinking fountains in popular public areas, and increasing the visibility of such fountains.

Improving Private Well Testing Programs: Experimental Evidence from Iowa

Approximately 23 million U.S. households rely on private wells for drinking water. This study first summarizes drinking water behaviors and perceptions from a large-scale survey of households that rely on private wells in Iowa. Few households test as frequently as recommended by public health experts. Around 40% of households do not regularly test, treat, or avoid their drinking water, suggesting pollution exposure may be widespread among this population. Next, we utilize a randomized control trial to study how nitrate test strips and information about a free, comprehensive water quality testing program influence households' behaviors and perceptions. The intervention significantly increased testing, including high-quality follow-up testing, but had limited statistically detectable impacts on other behaviors and perceptions. Households' willingness to pay for nitrate test kits and testing information exceeds program costs, suggesting that the intervention was welfare-enhancing.

Association of Water Arsenic With Incident Diabetes in U.S. Adults: The Multi-Ethnic Study of Atherosclerosis and the Strong Heart Study

OBJECTIVE

We examined the association of arsenic in federally regulated community water systems (CWS) and unregulated private wells with type 2 diabetes (T2D) incidence in the Strong Heart Family Study (SHFS), a prospective study of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially and ethnically diverse urban U.S. communities.

RESEARCH DESIGN AND METHODS

We evaluated 1,791 participants from SHFS and 5,777 participants from MESA who had water arsenic estimates available and were free of T2D at baseline (2001-2003 and 2000-2002, respectively). Participants were followed for incident T2D until 2010 (SHFS cohort) or 2019 (MESA cohort). We used Cox proportional hazards mixed-effects models to account for clustering by family and residential zip code, with adjustment for sex, baseline age, BMI, smoking status, and education.

RESULTS

T2D incidence was 24.4 cases per 1,000 person-years (mean follow-up, 5.6 years) in SHFS and 11.2 per 1,000 person-years (mean follow-up, 14.0 years) in MESA. In a meta-analysis across the SHFS and MESA cohorts, the hazard ratio (95% CI) per doubling in CWS arsenic was 1.10 (1.02, 1.18). The corresponding hazard ratio was 1.09 (0.95, 1.26) in the SHFS group and 1.10 (1.01, 1.20) in the MESA group. The corresponding hazard ratio (95% CI) for arsenic in private wells and incident T2D in SHFS was 1.05 (0.95, 1.16). We observed statistical interaction and larger magnitude hazard ratios for participants with BMI <25 kg/m2 and female participants.

CONCLUSIONS

Low to moderate water arsenic levels (<10 µg/L) were associated with T2D incidence in the SHFS and MESA cohorts.

Inclusion of Drinking Water Source and Testing Questions into Electronic Medical Records: Advancing Environmental Medicine and Public Health Outreach in New Jersey

Chronic arsenic exposure is associated with adverse health outcomes, and early life exposure is particularly damaging. Households with pregnant people and young children drinking from unregulated wells in arsenic-prevalent regions are therefore a public health priority for outreach and intervention. A partnership between Columbia University, New Jersey government partners, and Hunterdon Healthcare has informed Hunterdon County residents of the risks faced from drinking arsenic-contaminated water and offered free well testing through a practice-based water test kit distribution and an online patient portal outreach. Encouraged by those successes, Hunterdon Healthcare incorporated questions about drinking water source and arsenic testing history into the electronic medical record (EMR) template used by most primary care practices in Hunterdon County. The new EMR fields allow for additional targeting of risk-based outreach and water test kit distribution, offering promising new opportunities for public health and environmental medicine outreach, surveillance, and research.

An overview of the Be Well Home Health Navigator Program to reduce contaminants in well water: Design and methods

BACKGROUND

The Be Well Home Health Navigator Program is a prospective, randomized controlled trial (RCT) implemented to compare a community health navigator program to usual care program to reduce contaminants in drinking water.

DESIGN AND SETTING

This 4-year two-armed RCT will involve well owners in Oregon that have private drinking water wells that contain arsenic, nitrate, or lead above maximum contaminant levels.

INTERVENTION

The intervention leverages the trusted relationship between Cooperative Extension Service (CES) Community Educators and rural well owners to educate, assist and motivate to make decisions and set actionable steps to mitigate water contamination. In this study, CES will serve as home health navigators to deliver: 1) individualized feedback, 2) positive reinforcement, 3) teach-back moments, 4) decision-making skills, 5) navigation to resources, 6) self-management, and 7) repeated contact for shaping and maintenance of behaviors. Usual care includes information only with no access to individual meetings with CES.

MEASURABLE OUTCOMES

Pre-specified primary outcomes include 1) adoption of treatment to reduce exposure to arsenic, nitrate, or lead in water which may include switching to bottled water and 2) engagement with well stewardship behaviors assessed at baseline, and post-6 and 12 months follow-up. Water quality will be measured at baseline and 12-month through household water tests. Secondary outcomes include increased health literacy scores and risk perception assessed at baseline and 6-month surveys.

IMPLICATIONS

The results will demonstrate the efficacy of a domestic well water safety program to disseminate to other CES organizations.

TRIAL REGISTRATION NUMBER

NCT05395663.

Prioritizing water availability study settings to address geogenic contaminants and related societal factors

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering additional water quality factors. This study presents a ranking based on the potential impacts of geogenic constituents on water quality and consideration of societal factors related to water quality. High-concentration geogenic constituents, including trace elements and radionuclides, are among the most prevalent contaminants limiting water availability in the USA and globally. Geogenic constituents commonly occur in groundwater because of subsurface water-rock interactions, and their distributions are controlled by complex geochemical processes. Geogenic constituent mobility can also be affected by human activities (e.g., mining, energy production, irrigation, and pumping). Societal factors and relations to drinking water sources and water quality information are often overlooked when evaluating research priorities. Sociodemographic characteristics, data gaps resulting from historical data-collection disparities, and infrastructure condition/age are examples of factors to consider regarding environmental justice. This paper presents approaches for ranking and prioritizing potential basin-scale study areas across the contiguous USA by considering a suite of conventional physical and geochemical variables related to geogenic constituents, with and without considering variables related to societal factors. Simultaneous consideration of societal and conventional factors could provide decision makers with more diverse, interdisciplinary tools to increase equity and reduce bias in prioritizing focused research areas and future water availability studies.

A state-by-state comparison of policies that protect private well users

BACKGROUND

While the Safe Drinking Water Act allows states and localities to adopt stronger protections for drinking water, state and local requirements concerning private drinking water wells vary dramatically and often do not provide necessary protections for residents who rely on well water.

OBJECTIVE

This paper inventories ten types of policies including laws, regulations, programs, and activities that states have adopted or partaken in to encourage safe drinking water for residential well owners.

METHODS

To identify categories of private well protections, we conducted a preliminary internet search with key search terms to create an initial list of 10 categories of laws, regulations, programs, and activities (collectively referred to as "policies") that states have taken to protect residential well water quality. To have a private well safety category present, the law, regulation, program, or activity must fit within the scope of the ten classifications. To limit the breadth of our search, we excluded local and county protections, as well as activities by non-governmental organizations. We also excluded basic construction standards for new wells and licensing standards for well drillers, both of which are covered under a previous study. We conducted an additional internet search to complete a comprehensive review of each state and category and to validate our previous findings. In addition to this internet search, we completed phone and email outreach to the state agencies implementing the well safety categories identified in our internet search to confirm our results.

RESULTS

The results indicate a wide range of state-based well water protections. The number of residential well water protections present in each state ranged from 8 policies in Iowa, Kentucky, and Maine to 1 policy in Oklahoma, with a median of 5 policies across the 50 states.

IMPACT

This paper examines protections that states have implemented to safeguard residential well water quality and to protect the health of people who rely on well water. This research reviews state-level regulations, laws, and programs, as opposed to local, municipal, county-level, or quasi-governmental protections for residential well owners. Residential well policies were examined across ten categories. Without any protections at the federal level, this research reveals gaps in state regulation and demonstrates the need for broader adoption of comprehensive state-level policies to better protect residential well owners from drinking water contaminants and their associated public health impacts.

Differential exposure to drinking water contaminants in North Carolina: Evidence from structural topic modeling and water quality data

To better understand water security of communities in North Carolina, this research uses structural topic modeling (STM) and geographic mapping to identify the main topics and pollutant categories being researched and the areas exposed to drinking water contaminants. The textual data derived from the journal article abstracts that examined water pollution in North Carolina is from 1964 to present. The STM analysis of textual data is paired with socio-demographic data from the 2015-2019 American Community Survey (ACS) 5-year estimates and water pollution data from North Carolina state agencies. The STM findings show that the most discussed topics relate to runoff management, wastewater from concentrated agricultural feeding operations, emerging contaminants, land development, and health impacts as a result of water contamination. The article discusses how the topics especially threaten groundwater resources used by community water systems and private wells. Those communities served by private wells are predominantly low-income and minority populations. As a result, threats to groundwater supplies exacerbate existing issues of environmental justice in North Carolina, especially in the Coastal Plains Region. The STM findings revealed that several key threats to safe drinking water are less covered by academic literature, such as poultry concentrated agricultural feeding operations and climate impacts, which may increase disparities in water access in North Carolina.

Targeted education and outreach to neighbors of homes with high gross alpha radioactivity in domestic well water

Gross alpha, a measurement of radioactivity in drinking water, is the most frequent laboratory test to exceed primary drinking water standards among wells tested under the New Jersey Private Well Testing Act (NJ PWTA). Certain geological factors prevalent in New Jersey (NJ) are primarily responsible for the presence of radioactivity in private well drinking water and thus, many of the estimated one million private well users in NJ may be at-risk of water contamination from naturally occurring radionuclides. Neighbor-based private well outreach methodology was utilized to identify high risk wells in both northern and southern NJ regions and offer free private well testing for radionuclides. Previously tested wells with gross alpha exceeding or equal to 3.7 becquerels per liter (Bq L^-1; 100 pCi/L) were selected (n = 49) to identify neighbors (n = 406) within 152.4 m (500 feet). Invitation letters were mailed to selected neighbors and some of the previously tested high wells (n = 12) offering free water sampling for the following parameters: gross alpha (48-hour rapid test), combined radium-226 and radium-228 (Ra-226 + Ra-228), uranium-238 (U-238), radon-222 (Rn-222) and iron. Overall, 70 neighbors and 5 high PWTA wells participated in this free water testing opportunity. For neighboring wells, gross alpha results revealed 47 (67.1%) wells exceeding the gross alpha MCL of 0.555 Bq L^-1 (15 pCi/L) mainly due to radium activity in the raw/untreated water. Of those with water treatment (n = 62), 12 (19.4%) treated water samples exceeded the gross alpha MCL. Targeting neighbors of known highly radioactive wells for private well testing is an effective public health outreach method and can also provide useful insight of regional contaminant variations.

Integrating consumer risk perception and awareness with simulation-based quantitative microbial risk assessment using a coupled systems framework: A case study of private groundwater users in Ontario

Private well users in Ontario are responsible for ensuring the potability of their own private drinking water source through protective actions (i.e., water treatment, well maintenance, and regular water quality testing). In the absence of regulation and limited surveillance, quantitative microbial risk assessment (QMRA) represents the most practical and robust approach to estimating the human health burden attributable to private wells. For an increasingly accurate estimation, QMRA of private well water should be represented by a coupled model, which includes both the socio-cognitive and physical aspects of private well water contamination and microbial exposure. The objective of the current study was to determine levels of waterborne exposure via well water consumption among three sub-groups (i.e., clusters) of private well users in Ontario and quantify the risk of waterborne acute gastrointestinal illness (AGI) attributed to Giardia, shiga-toxin producing E. coli (STEC) and norovirus from private drinking water sources in Ontario. Baseline simulations were utilized to explore the effect of varying socio-cognitive scenarios on model inputs (i.e., increased awareness, protective actions, aging population). The current study uses a large spatio-temporal groundwater quality dataset and cross-sectional province-wide survey to create socio-cognitive-specific QMRA simulations to estimate the risk of waterborne AGI attributed to three enteric pathogens in private drinking waters source in Ontario. Findings suggest significant differences in the level of exposure among sub-groups of private well users. Private well users within Cluster 3 are characterised by higher levels of exposure and annual illness attributable to STEC, Giardia and norovirus than Clusters 1 and 2. Provincial incidence rates of 520.9 (1522 illness per year), 532.1 (2211 illness per year) and 605.5 (5345 illness per year) cases/100,000 private well users per year were predicted for private well users associated with Clusters 1 through 3. Established models will enable development of necessary tools tailored to specific groups of at-risk well users, allowing for preventative public health management of private groundwater sources.

Assessing the risk of acute gastrointestinal illness attributable to three enteric pathogens from contaminated private water wells in Ontario

The province of Ontario compromises the largest groundwater reliant population in Canada serving approximately 1.6 million individuals. Unlike municipal water systems, private well water is not required to meet water quality regulatory standards and thus source maintenance, treatment and testing remains the responsibility of the well owner. Infections associated with private drinking water systems are rarely documented given their typically sporadic nature, thus the human health effects (e.g., acute gastrointestinal illness (AGI)) on consumers remains relatively unknown, representing a significant gap in water safety management. The current study sought to quantify the risk of waterborne AGI attributed to Giardia, shiga-toxin producing E. coli (STEC) and norovirus from private drinking water sources in Ontario using Monte Carlo simulation-based quantitative microbial risk assessment (QMRA). Findings suggest that consumption of contaminated private well water in Ontario is responsible for approximately 4823 AGI cases annually, with 3464 (71.8%) and 1359 (28.1%) AGI cases predicted to occur in consolidated and unconsolidated aquifers, respectively. By pathogen, waterborne AGI was attributed to norovirus (62%; 2991/4823), Giardia (24.6%; 1186/4823) and STEC (13.4%; 646/4823). The developed QMRA framework was used to assess the potential health impacts of partial and total well water treatment system failure. In the unlikely event of total treatment failure, total mean annual illnesses are predicted to almost double (4217 to 7064 cases per year), highlighting the importance of effective water treatment and comprehensive testing programs in reducing infectious health risks attributable to private well water in Ontario. Study findings indicate significant underreporting of waterborne AGI rates at the provincial level likely biasing public health interventions and programs that are effective in monitoring and minimizing the health risk associated with private well water.

Disparities in Drinking Water Manganese Concentrations in Domestic Wells and Community Water Systems in the Central Valley, CA, USA

Over 1.3 million Californians rely on unmonitored domestic wells. Existing probability estimates of groundwater Mn concentrations, population estimates, and sociodemographic data were integrated with spatial data delineating domestic well communities (DWCs) to predict the probability of high Mn concentrations in extracted groundwater within DWCs in California's Central Valley. Additional Mn concentration data of water delivered by community water systems (CWSs) were used to estimate Mn in public water supply. We estimate that 0.4% of the DWC population (2342 users) rely on groundwater with predicted Mn > 300 μg L^-1. In CWSs, 2.4% of the population (904 users) served by small CWSs and 0.4% of the population (3072 users) served by medium CWS relied on drinking water with mean point-of-entry Mn concentration >300 μg L^-1. Small CWSs were less likely to report Mn concentrations relative to large CWSs, yet a higher percentage of small CWSs exceed regulatory standards relative to larger systems. Modeled calculations do not reveal differences in estimated Mn concentration between groundwater from current regional domestic well depth and 33 m deeper. These analyses demonstrate the need for additional well-monitoring programs that evaluate Mn and increased access to point-of-use treatment for domestic well users disproportionately burdened by associated costs of water treatment.

Drinking Water From Private Wells and Risks to Children

Drinking water for approximately 23 million US households is obtained from private wells. These wells can become contaminated by pollutant chemicals or pathogenic organisms, leading to significant illness. Although the US Environmental Protection Agency and all states offer guidance for construction, maintenance, and testing of private wells, most states only regulate the construction of new private water wells. With a few exceptions, there is little regulation after construction. Well owners are responsible for their own wells. Children may also drink well water at child care or when traveling. Illness resulting from children’s ingestion of contaminated water can be severe. This report reviews relevant aspects of groundwater and wells; describes the common chemical and microbiologic contaminants; gives an algorithm with recommendations for inspection, testing, and remediation for wells providing drinking water for children; and provides references and Internet resources for more information.

Estimating the duration and overlap of Escherichia coli contamination events in private groundwater supplies for quantitative risk assessment using a multiannual (2010-2017) provincial dataset

Approximately 1.6 million individuals in Ontario rely on private water wells. Private well water quality in Ontario remains the responsibility of the well owner, and due to the absence of regulation, quantitative microbial risk assessment (QMRA) likely represents the most effective approach to estimating and mitigating waterborne infection risk(s) from these supplies. Annual contamination duration (i.e., contaminated days per annum) represents a central input for waterborne QMRA; however, it is typically based on laboratory studies or meta-analyses, thus representing an important limitation for risk assessment, as groundwater mesocosms cannot accurately replicate subsurface conditions. The present study sought to address these limitations using a large spatio-temporal in-situ groundwater quality dataset (>700,000 samples) to evaluate aquifer-specific E. coli die-off rates (CFU/100 mL per day decline), subsequent contamination sequence duration(s) and the likelihood of overlapping contamination events. Findings indicate median E. coli die-off rates of 0.38 CFU/100 mL per day and 0.64 CFU/100 mL per day, for private wells located in unconsolidated and consolidated aquifers, respectlvely, with mean calculated contamination sequence durations of 18 days (unconsolidated) and 11 days (consolidated). Study findings support and permit development of increasingly evidence-based, regionally- and temporally-specific quantitative waterborne risk assessment.

Water Quality from the Sources of Non-Centralized Water Supply within the Rural Settlements of Zhytomyr Region

The research was conducted within the territories of rural settlements of Zhytomyr region. A total of 72 sources of non-centralized water supply were surveyed. Water quality was assessed by physical and chemical (pH, iron total, total water hardness) and toxicological (nitrites, nitrates, and ammonium) indicators, the content of which was compared with the norms given in the State Sanitary Regulations and Standards 2.2.4-171-10 “Hygienic Requirements for Drinking Water Intended for Human Consumption.” The assessment of drinking water quality was carried out in accordance with DSTU (National Standards of Ukraine) 4808:2007 and with the water quality index (WQI). It was found that the largest deviations from the norm among toxicological indicators were observed for nitrates – 63.9%. In terms of water quality classes according to DSTU 4808:2007, drinking water from sources of non-centralized water supply of villages showed the following distribution: 2.8% of the samples belonged to class 1 (excellent water quality), 72.2% to class 2, and 25% to class 3. According to WQI, 16.7% of the examined sources of non-centralized water supply had excellent water, 63.9% had good water, and 19.4% had poor water. Despite the fact that the water from the investigated sources of non-centralized water supply was of acceptable quality, it is impotable due to the excessive nitrate content. The results obtained show that there is a need for monitoring of drinking water quality from the sources of non-centralized water supply, especially in rural settlements that are not provided with centralized water supply.

The Survey of the Health of Wisconsin (SHOW) Program: An Infrastructure for Advancing Population Health

Introduction

The Survey of the Health of Wisconsin (SHOW) was established in 2008 by the University of Wisconsin (UW) School of Medicine and Public Health (SMPH) with the goals of (1) providing a timely and accurate picture of the health of the state residents; and (2) serving as an agile resource infrastructure for ancillary studies. Today, the SHOW program continues to serve as a unique and vital population health research infrastructure for advancing public health.

Methods

SHOW currently includes 5,846 adult and 980 minor participants recruited between 2008 and 2019 in four primary waves. WAVE I (2008–2013) includes annual statewide representative samples of 3,380 adults ages 21 to 74 years. WAVE II (2014–2016) is a triannual statewide sample of 1,957 adults (age ≥18 years) and 645 children (age 0–17). WAVE III (2017) consists of follow-up of 725 adults from the WAVE I and baseline surveys of 222 children in selected households. WAVEs II and III include stool samples collected as part of an ancillary study in a subset of 784 individuals. WAVE IV consists of 517 adults and 113 children recruited from traditionally under-represented populations in biomedical research including African Americans and Hispanics in Milwaukee, Wisconsin.

Findings to Date

The SHOW resource provides unique spatially granular and timely data to examine the intersectionality of multiple social determinants and population health. SHOW includes a large biorepository and extensive health data collected in a geographically diverse urban and rural population. Over 60 studies have been published covering a broad range of topics including, urban and rural disparities in cardio-metabolic disease and cancer, objective physical activity, sleep, green-space and mental health, transcriptomics, the gut microbiome, antibiotic resistance, air pollution, concentrated animal feeding operations and heavy metal exposures.

Discussion

The SHOW cohort and resource is available for continued follow-up and ancillary studies including longitudinal public health monitoring, translational biomedical research, environmental health, aging, microbiome and COVID-19 research.

Societal aspects of NORM: An overlooked research field

While technical aspects of exposures to the naturally occurring radioactive material (NORM) are well explored, social science research on NORM is scarce, poorly indexed and dispersed across peer-reviewed literature, as well as various academic disciplines. Through an exploratory review of grey literature and a systematic review of scientific peer-reviewed articles published until December 2020, this paper addresses the following questions: (a) What are the societal challenges related to NORM? (b) What type of scientific research is being conducted on the societal aspects of NORM and (c) To what extent do the findings answer the identified challenges? Unfortunately, results of this study demonstrate a research gap related to the social, economic and cultural aspects of NORM management. Although the few existing studies offer some insights, for instance in relation to risk perception and risk communication, most of the societal challenges identified have not been addressed yet. This demonstrates the strong need for evidence based social science studies in order to improve the management of NORM.

User experience of point-of-use water treatment for private wells in North Carolina: Implications for outreach and well stewardship

Private well users are potentially exposed to a range of chemical contaminants through their drinking water. Point-of-use (POU) water treatment represents one potential solution to reduce harmful exposures through well water, but well users frequently do not adopt household treatment even if they learn their water is contaminated. This study elucidates the experiences, perceptions, and beliefs of 17 households on private wells in North Carolina that participated in a pilot-scale POU water treatment intervention to better understand the drivers and barriers of POU treatment adoption among well users. The intervention consisted of an under-sink activated carbon block POU filter designed to remove lead and two long-chain perfluoroalkyl acids. Filter effluents and influents were tested monthly for eight months. Questionnaires administered before and after the intervention showed a significant decrease in participants' perceived vulnerability to well water contamination, with 77% feeling vulnerable to poor well water quality before, compared to 23% after the filter was installed. However, the POU filters did not fully eliminate feelings of water insecurity (for example, concerns about exposure to contaminants when bathing remained). Lack of knowledge and skills associated with installing and maintaining POU treatment were important barriers to adoption for some well users. Perceptions of POU treatment were also significantly correlated with the intent to implement other well stewardship behaviors such as well water testing. The results highlight the need for strengthened outreach and support programs that provide technical assistance, education, and financial support for households relying on private wells.

Examining the dynamics of the relationship between water pH and other water quality parameters in ground and surface water systems

This study evaluated the relationship between water pH and the physicochemical properties of water while controlling for the influence of heavy metals and bacteriological factors using a nested logistic regression model. The study further sought to assess how these relationships are compared across confined water systems (ground water) and open water systems (surface water). Samples were collected from 100 groundwater and 132 surface water locations in the Tarkwa mining area. For the zero-order relationship in groundwater, EC, TDS, TSS, Ca, SO42-, total alkalinity, Zn, Mn, Cu, faecal and total coliform were more likely to predict optimal water pH. For surface water however, only TSS, turbidity, total alkalinity and Ca were significant predictors of optimal pH levels. At the multivariate level for groundwater, TDS, turbidity, total alkalinity and TSS were more likely to predict optimal water pH while EC, Mg, Mn and Zn were associated with non-optimal water pH. For the surface water system, turbidity, Ca, TSS, NO3, Mn and total coliform were associated with optimal water pH while SO42-, EC, Zn, Cu, and faecal coliform were associated with non-optimal water pH. The non-robustness of predictors in the surface water models were conspicuous. The results indicate that the relationship between water pH and other water quality parameters are different in different water systems and can be influenced by the presence of other parameters. Associations between parameters are steadier in groundwater systems due to its confined nature. Extraneous inputs and physical variations subject surface water to constant variations which reflected in the non-robustness of the predictors. However, the carbonate system was influential in how water quality parameters associate with one another in both ground and surface water systems. This study affirms that chemical constituents in natural water bodies react in the environment in far more complicated ways than if they were isolated and that the interaction between various parameters could predict the quality of water in a particular system.

Private wells as potential sources of heavy metal exposure: a pilot study in northwest Slovakia

OBJECTIVES

The aim of this study is to analyse levels of selected heavy metals: chromium (Cr), cadmium (Cd), copper (Cu), manganese (Mn), and lead (Pb), and to recognize factors related to wells' stewardship.

METHODS

The pilot study was realized in May 2018 in three villages in northwest of Slovakia. We analysed 69 water samples from private wells. The data on wells and well owners were obtained by self-administered questionnaire. The samples were analysed by atomic absorption spectroscopy with graphite furnace GF AAS (AAS GBC XplorAA 5000 with GBC GF 5000) equipped with hollow cathode lamps. Levels of heavy metals were compared with parametric values for drinking water stated in the Resolution of the Ministry of Health of the Slovak Republic No. 247/2017 Coll.

RESULTS

The results indicated spatial variability in some heavy metal levels. Cadmium was not quantified in any sample. Copper and chromium levels were below the parametric value. Parametric values for manganese and lead were exceeded in 19 (27.5%) and 2 (2.9%) samples, respectively. Only 18 owners tested water quality. Busyness and financial cost most frequently discouraged users to carry out the water quality analysis.

CONCLUSIONS

The presence of heavy metals in well water can pose a serious public health problem, especially in rural areas without public water supply. Education on heavy metals' risks targeted at well owners could increase the awareness of the issue and minimize possible public health consequences.

Private groundwater management and risk awareness: A cross-sectional analysis of two age-related subsets in the Republic of Ireland

Risk communication represents the optimal instrument for decreasing the incidence of private groundwater contamination and associated waterborne illnesses. However, despite attempts to promote voluntary well maintenance in high groundwater-reliant regions such as the Republic of Ireland, awareness levels of supply status (e.g. structural integrity) have remained low. As investigations of supply awareness are often thematically narrow and homogeneous with respect to sub-population, revised analyses of awareness among both current and future supply owners (i.e. adults of typical well owner and student age) are necessary. Accordingly, the current study utilised a national survey of well users and an age-based comparison of supply awareness. Awareness was measured among 560 Irish private well users using a multi-domain scoring framework and analysed in conjunction with experiential variables including experience of extreme weather events and previous household infections, and perceived self-efficacy in maintaining supply. Respondents displayed a median overall awareness score of 66.7%, with supply owners (n = 399) and students (n = 161) exhibiting median scores of 75% and 58.3%. Awareness among both combined respondent subsets and well owners was significantly related to gender, well use factors and self-perceived behavioural efficacy while awareness among students was not correlated with any independent variable. Cluster analysis identified three distinct respondent groups characterised by awareness score and gender in both current and future well owner subsets. Male well owners and students displayed higher perceived self-efficacy irrespective of awareness score while female well owners that demonstrated high awareness were significantly more likely to report postgraduate educational (p < 0.001). Findings suggest that recent experience of extreme weather events does not significantly influence supply awareness and mirror previously identified knowledge differences between well owners and young adults. Age, gender, supply use and perceived self-efficacy emerge as recurring focal points and accordingly merit consideration from groundwater and health communication practitioners for future risk interventions.

Characteristics and Behaviors Among a Representative Sample of New Jersey Adults Practicing Environmental Risk-Reduction Behaviors

CONTEXT

Environmental exposure to groundwater contamination from agricultural runoff, chemical pollution, or geology and indoor air hazards from misuse of consumer products or naturally occurring radon contributes to adverse health outcomes. Individuals can reduce exposure to environmental hazards by practicing risk-reduction behaviors.

OBJECTIVE

To characterize the demographic and behavioral characteristics of the population practicing environmental risk-reduction behaviors in order to identify gaps in current prevention outreach efforts.

DESIGN

The New Jersey Behavioral Risk Factor Survey captures data on self-reported environmental risk-reduction behaviors and health-promoting behaviors (cancer screenings, vaccinations, smoking). To account for complex survey data, weighted analyses were performed in SAS v9.4.

SETTING

New Jersey, 2014-2015.

PARTICIPANTS

The New Jersey Behavioral Risk Factor Survey is an ongoing telephone health survey of NJ residents. About 1000 NJ residents are selected randomly each month to derive statewide representative prevalence estimates.

MAIN OUTCOME MEASURES

Self-reported private well testing, radon screening, and carbon monoxide (CO) detector ownership.

RESULTS

Statewide prevalence of the practice of environmental risk-reduction practices includes 56.6% for private well testing, 44.3% for radon screening, and 86.1% for CO detector ownership. A larger percentage of individuals who are white or Asian, college-educated, earn more than $50 000, and own their homes reported CO detector ownership and radon screening. Age was the only demographic factor associated with private well testing. Screening for radon and CO detector ownership was positively associated with receiving an influenza shot, colonoscopy, aerobic exercise, and positive self-reported health and not smoking.

CONCLUSIONS

There is a need to improve rates of environmental risk-reduction behaviors and reduce disparities in the practice of these behaviors through efforts to increase awareness. Public health officials should target outreach to specific populations that do not practice risk-reduction behaviors.

Structure and Functional Attributes of Bacterial Communities in Premise Plumbing Across the United States

Microbes that thrive in premise plumbing can have potentially important effects on human health. Yet, how and why plumbing-associated microbial communities vary across broad spatial scales remain undetermined. We characterized the bacterial communities in 496 showerheads collected from across the continental United States. The overall community structure, determined by 16S rRNA gene amplicon sequencing, revealed high levels of bacterial diversity. Although a large fraction of the observed variation in community composition could not be explained, differences in bacterial community composition were associated with water supply (private well water vs public municipal water), water source (groundwater vs surface water), and associated differences in water chemistry (pH and chlorine). Most notably, showerheads in homes supplied with public water had higher abundances of Blastomonas, Mycobacterium, and Porphyrobacter, while Pseudorhodoplanes, Novosphingobium, and Nitrospira were more abundant in those receiving private well water. We conducted shotgun metagenomic analyses on 92 of these samples to assess differences in genomic attributes. Public water-sourced showerheads had communities enriched in genes related to lipid and xenobiotic metabolisms, virulence factors, and antibiotic resistance. In contrast, genes associated with oxidative stress and membrane transporters were over-represented in communities from private well water-sourced showerheads compared to those supplied by public water systems. These results highlight the broad diversity of bacteria found in premise plumbing across the United States and the role of the water source and treatment in shaping the microbial community structure and functional potential.

Are carbon water filters safe for private wells? Evaluating the occurrence of microbial indicator organisms in private well water treated by point-of-use activated carbon block filters

Point-of-use (POU) water treatment is highly relevant to private well users vulnerable to chemical contamination, but uncertainty remains around the effects of activated carbon based POU devices on the microbial quality of the treated water. In this study, under-sink activated carbon block water filters were installed in 17 homes relying on private well water in North Carolina. The influent and effluent water in each home was evaluated for bacterial and viral microbial indicator organisms monthly for five months. Multiple logistic regression was used to identify water quality and water usage variables that were significant predictors of each indicator organism occurring in the filter effluent. The odds of total coliforms occurring in the effluent decreased by 84% with each 1-log₁₀ increase in the influent HPC (p < 0.05), suggesting a protective effect by native heterotrophic bacteria, but increased by over 50 times with low cumulative water use (p < 0.05). The filters were not protective against coliphages in the influent and viral shedding may occur after periods of increased virus concentrations in the raw well water. Specific bacteria were also found to increase in the effluent, causing a shift in the bacterial community composition, although potential opportunistic pathogens were detected in both the influent and the effluent. Overall, under normal conditions of use, the filters tested in this study did not represent a significant additional risk for well users beyond the existing exposures from undisinfected well water alone.

Methods for Estimating Locations of Housing Units Served by Private Domestic Wells in the United States Applied to 2010

In 1990, the last time the decennial census included a question on domestic drinking water source, it was estimated that private domestic water wells (PDWs) supplied household water to about 15.1 million housing units (15% of the population) in the United States (U.S.). PDWs are not regulated by the Safe Drinking Water Act, and with few exceptions, are not subject to the water quality testing required of public water suppliers. We expanded two methods in estimating housing units reliant on PDWs from an Oklahoma pilot study (Weaver et al. 2017), nationally. Both use 1990 census data on drinking water sources as a baseline. The first method uses housing unit change and private well drilling logs for 20 states. This allows for the rate of well use to change between 1990 and 2010 in these states. The second, based solely on housing unit change, assumes a constant rate of well use. Ordinary least squares regression demonstrated (R ² = 0.78) that the methods yield similar estimates for nationwide well use. Using the housing unit change method, it is estimated that in 2010, 23 million housing units were reliant on PDWs (17% of the population). We provide these estimates at the census block group and census block resolution. This dataset will assist in a better understanding of the reliance on PDWs in the U.S., and position local, tribal, state, and national groups to better protect this water resource from contaminant sources.

RESEARCH IMPACT STATEMENT

The work provides improved estimates of the spatial distribution of housing units reliant on private domestic wells in the United States and a foundation to protect this water supply at all levels of government.

Drinking Water Consumption Patterns among Private Well Users in Ontario: Implications for Exposure Assessment of Waterborne Infection

Understanding the water consumption patterns within a specific population informs development of increasingly accurate, spatially specific exposure and/or risk assessment of waterborne infection. The current study examined the consumption patterns of private well users in Ontario while considering potentially influential underlying sociodemographics, household characteristics, and experiential factors. A province-wide online survey was circulated between May and August 2018 (n = 1,162). Overall, 81.5% of respondents reported daily well water consumption (i.e., tap water). Results indicate a mean daily well water consumption rate of 1,132 mL/day (SD = 649 mL/day) among well water consumers. Gender was significantly associated with well water consumption, with higher consumption rates found among female respondents. The experience of acute gastrointestinal illness (AGI) symptoms or diagnosis in the past 12 months did not impact the volume of water consumed, suggesting that experiencing previous AGI does not decrease consumption volumes, and therefore exposure over time. Significantly higher rates of well water consumption were found among respondents who reported previous testing or ongoing water treatment. Approximately 45.5% of survey respondents who stated that they do not consume well water selected bottled water as their primary household drinking water supply. Bottled water consumption was also not associated with previous AGI experiences. Findings will inform future quantitative microbial risk assessments associated with private well water use by providing spatially and demographically specific estimates of well water consumption.

Associations between private well water and community water supply arsenic concentrations in the conterminous United States

Geogenic arsenic contamination typically occurs in groundwater as opposed to surface water supplies. Groundwater is a major source for many community water systems (CWSs) in the United States (US). Although the US Environmental Protection Agency sets the maximum contaminant level (MCL enforceable since 2006: 10 μg/L) for arsenic in CWSs, private wells are not federally regulated. We evaluated county-level associations between modeled values of the probability of private well arsenic exceeding 10 μg/L and CWS arsenic concentrations for 2231 counties in the conterminous US, using time invariant private well arsenic estimates and CWS arsenic estimates for two time periods. Nationwide, county-level CWS arsenic concentrations increased by 8.4 μg/L per 100% increase in the probability of private well arsenic exceeding 10 μg/L for 2006-2008 (the initial compliance monitoring period after MCL implementation), and by 7.3 μg/L for 2009-2011 (the second monitoring period following MCL implementation) (1.1 μg/L mean decline over time). Regional differences in this temporal decline suggest that interventions to implement the MCL were more pronounced in regions served primarily by groundwater. The strong association between private well and CWS arsenic in Rural, American Indian, and Semi Urban, Hispanic counties suggests that future research and regulatory support are needed to reduce water arsenic exposures in these vulnerable subpopulations. This comparison of arsenic exposure values from major private and public drinking water sources nationwide is critical to future assessments of drinking water arsenic exposure and health outcomes.

The Survey of the Health of Wisconsin (SHOW) Program: An infrastructure for Advancing Population Health Sciences

PURPOSE

The Survey of the Health of Wisconsin (SHOW) was established in 2008 by the University of Wisconsin (UW) School of Medicine and Public Health (SMPH) with the goals of 1) providing a timely and accurate picture of the health of the state residents; and 2) serving as an agile resource infrastructure for ancillary studies. Today SHOW continues to serve as a vital population health research infrastructure.

PARTICIPANTS

SHOW currently includes 5,846 adult and 980 minor participants recruited between 2008-2019 in four primary waves. WAVE I (2008-2013) includes annual statewide representative samples of 3,380 adults ages 21 to 74 years. WAVE II (2014-2016) is a triannual statewide sample of 1957 adults (age ≥18 years) and 645 children. WAVE III (2017) consists of follow-up of 725 adults from the WAVE I and baseline surveys of 222 children in selected households. WAVEs II and III include stool samples collected as part of an ancillary study in a subset of 784 individuals. WAVE IV consist of 517 adults and 113 children recruited from traditionally under-represented populations in biomedical research including African Americans and Hispanics in Milwaukee county, WI.

FINDINGS TO DATE

The SHOW provides extensive data to examine the intersectionality of multiple social determinants and population health. SHOW includes a large biorepository and extensive health data collected in a geographically diverse urban and rural population. Over 60 studies have been published covering a broad range of topics including, urban and rural disparities in cardio-metabolic disease and cancer, objective physical activity, sleep, green-space and mental health, transcriptomics, the gut microbiome, antibiotic resistance, air pollution, concentrated animal feeding operations and heavy metal exposures.

FUTURE PLANS

The SHOW cohort is available for continued longitudinal follow-up and ancillary studies including genetic, multi-omic and translational environmental health, aging, microbiome and COVID-19 research.

ARTICLE SUMMARY

Strengths and limitations: The Survey of the Health of Wisconsin (SHOW) is an infrastructure to advance population health sciences including biological sample collection and broader data on individual and neighborhood social and environmental determinants of health.The extensive data from diverse urban and rural populations offers a unique study sample to compare how socio-economic gradients shape health outcomes in different contexts.The objective health data supports novel interdisciplinary research initiatives and is especially suited for research in causes and consequences of environmental exposures (physical, chemical, social) across the life course on cardiometabolic health, immunity, and aging related conditions.The extensive biorepository supports novel omics research into common biological mechanisms underlying numerous complex chronic conditions including inflammation, oxidative stress, metabolomics, and epigenetic modulation.Ancillary studies, such as the Wisconsin Microbiome Study, have expanded the utility of the study to examine human susceptibility to environmental exposures and opportunities for investigations of the role of microbiome in health and disease.Long-standing partnerships and recent participation among traditionally under-represented populations in biomedical research offer numerous opportunities to support community-driven health equity work.No biological samples were collected among children.The statewide sampling frame may limit generalizability to other regions in the United States.

Examining influential drivers of private well users' perceptions in Ontario: A cross-sectional population study

Private well users are responsible for managing and maintaining the quality of their drinking water source. Previous studies in Canada have reported low testing rates among well users, a cornerstone of well stewardship behaviours that can prevent the consumption of contaminated groundwater. To improve well stewardship, it is important to understand the interactions between, and the impacts of, various factors that may influence behaviours. Accordingly, the objective of the current study was to investigate the impact of socio-demographics, property characteristics, and experiences with well construction and acute gastrointestinal illness (AGI) (i.e., previous experiences) on levels of awareness, attitudes, risk perceptions, and beliefs (i.e., risk domains) among private well users in Ontario. A link to a province-wide online survey was circulated between May and August 2018 and novel "risk domain" scoring protocols were developed to classify and summarize response data. The survey was undertaken by 1228 respondents, of which 1030 completed the survey in full. Results indicate a low level of waterborne pathogen awareness, with 50.8% of respondents unaware of any groundwater associated pathogens. Respondents' geographic location, gender, and well type were significantly associated with well users' attitudes and perceptions of risk regarding their personal well water supply and the quality and quantity of local groundwater sources. Higher levels of awareness and lower risk perception scores (i.e., lower perceptions of risk) were associated with residential presence during well construction (p < 0.001 and p = 0.017, respectively). Previous case(s) of AGI within the respondent's household were significantly associated with negative attitudes towards their well water (p < 0.001) and higher risk perception scores (p = 0.025) with respect to the quantity of local groundwater sources. Results may be used to identify critical experiential control points (e.g., during well construction or after a physician confirmed AGI diagnosis) and develop improved risk management and communication strategies aimed at private well users.

Private Wells and Rural Health: Groundwater Contaminants of Emerging Concern

PURPOSE OF REVIEW

Approximately 12% of the population in the US and Canada rely on federally unregulated private wells, which are common in rural areas and may be susceptible to microbiological and chemical contamination. This review identifies and summarizes recent findings on contaminants of emerging concern in well water across the US and Canada.

RECENT FINDINGS

Private well water quality modeling is complicated by the substantial variability in contamination sources, well construction, well depth, and the hydrogeology of the environment surrounding the well. Temporal variation in contaminant levels in wells suggests the need for monitoring efforts with greater spatial and temporal coverage. More extensive private well monitoring will help identify wells at greater risk of contamination, and in turn, public health efforts can focus on education and outreach to improve monitoring, maintaining, and treating private wells in these communities. Community interventions need to be coupled with stricter regulations and financing mechanisms that can support and protect private well owners.

Private well water testing promotion in pediatric preventive care: A randomized intervention study

Over 43 million U.S. residents rely on private unregulated wells for their drinking water, raising public health concerns, particularly in regions like northern New England where widespread groundwater arsenic contamination is now recognized. Children are particularly vulnerable to adverse health effects from arsenic exposure. Despite AAP Guidelines, approaches to engage pediatric clinicians in promoting private well testing have not been previously described. We sought to determine the most effective practice approaches to achieve successful well water testing in routine pediatric care. 12 primary care clinics were block randomized to one of four study arms. Two intervention variables were assessed: (1) test results access (parent only vs. parent and clinic) and (2) follow up approaches (yes/no). Parents of children under 12 months using a private well were eligible. Prepaid water tests were provided. Primary outcome was parental water test completion. Eleven clinics successfully implemented processes identifying well users. 240 testing kits were dispensed. Completion rates averaged 29% (range 10 to 61%). The study arm with both clinic results access and staff follow up system was 2.3 times more likely to achieve test completion than other arms (95% CI 1.12-4.86, p = .03). Kit distribution by clinicians versus nursing staff, irrespective of study arm, had 2.4 times greater completion (95% CI 1.13-5.11, p = .02). Systematic drinking water source screening can be improved in pediatric care. Higher testing completion was found in practices randomized to reminders and structured follow up versus single visit discussion, but clinician involvement was the most predictive factor.

Health and economic impact of nitrate pollution in drinking water: a Wisconsin case study

Nitrate contamination of drinking water, common in agricultural areas, increases the risk of certain cancers and impacts fetal development during pregnancy. Building on previously published methodology, this study evaluates nitrate-attributable disease cases and adverse birth outcomes as well as their economic costs for Wisconsin, USA. Nitrate is the most common contaminant in groundwater in Wisconsin. Two-thirds of the state's residents use groundwater as the primary source of drinking water. Here, we analyze nitrate exposure from drinking water in Wisconsin based on nitrate test results for community water systems for the period of 2010-2017 and a novel methodology for estimating nitrate exposure for the 28% of state's residents who use private wells. We estimate that annually, 111-298 combined cases of colorectal, ovarian, thyroid, bladder, and kidney cancer in Wisconsin may be due to nitrate contamination of drinking water. Each year, up to 137-149 cases of very low birth weight, 72-79 cases of very preterm birth, and two cases of neural tube defects could be due to nitrate exposure from drinking water. The direct medical cost estimates for all nitrate-attributable adverse health outcomes range between $23 and $80 million annually. Simulating targeted reductions in the counties with the highest current drinking water nitrate concentrations resulted in similar reductions in adverse health outcomes as statewide reduction efforts, up to nitrate reductions of 20%. Time trend analysis suggests that groundwater nitrate concentrations are overall increasing. Thus, nitrate contamination of water supplies in Wisconsin is a public health problem that needs to be addressed.

Water quality perceptions and private well management: The role of perceived risks, worry and control

Mismanagement of drinking water supplies can pose serious public health risks. There are many concerns about water source management among private well owners, as they are often solely responsible for maintaining their wells, and monitoring and testing of their own water quality. Lack of worry about contamination and a strong sense of control over risks in relation to drinking water quality have been identified as important factors that influence peoples' perceptions and behaviour. In this paper, we investigated how worry and perceived control moderate the influence of risk perceptions on water quality perceptions and well owners' maintenance behaviours. We compare a sample of private well owners (N = 167) with a sample of members of Group Water Schemes (GWS) (N = 160) and people who are supplied via the public mains (N = 195), to validate our results. We found that, in comparison to the other groups, well owners believe that water from private wells is superior and they express a higher level of control over contamination risks of their drinking water. Moreover, strong feelings of control suppress their perceptions of risk in relation to water quality. However, well owners who feel largely in control also maintain their well more frequently. We discuss the implications of these results for communication strategies with well owners.

Children drinking private well water have higher blood lead than those with city water

In the United States, 13% of households depend on an unregulated private well for their water. Compared with children in houses served by a regulated water utility, children in these homes have a 25% increased risk of elevated blood lead. Because lead is a neurotoxin, these children are at greater risk of experiencing irreversible cognitive damage, which can decrease their performance in school and increase their risks of behavioral problems. This study assesses associations between children’s blood lead and dependence on an unregulated private well for drinking water. It highlights the need for interventions to control lead corrosion from plumbing and well components (such as drop pipes, pump parts, and valves and fittings) in households depending on private wells.

Although the Flint, Michigan, water crisis renewed concerns about lead (Pb) in city drinking water, little attention has been paid to Pb in private wells, which provide drinking water for 13% of the US population. This study evaluates the risk of Pb exposure in children in households relying on private wells. It is based on a curated dataset of blood Pb records from 59,483 North Carolina children matched with household water source information. We analyze the dataset for statistical associations between children’s blood Pb and household drinking water source. The analysis shows that children in homes relying on private wells have 25% increased odds (95% CI 6.2 to 48%, P < 0.01) of elevated blood Pb, compared with children in houses served by a community water system that is regulated under the Safe Drinking Water Act. This increased Pb exposure is likely a result of corrosion of household plumbing and well components, because homes relying on private wells rarely treat their water to prevent corrosion. In contrast, corrosion control is required in regulated community water systems. These findings highlight the need for targeted outreach to prevent Pb exposure for the 42.5 million Americans depending on private wells for their drinking water.

A geostatistical study of socioeconomic status (SES), rurality, seasonality and index test results as drivers of free private groundwater testing in southern Ontario, 2012-2016

Approximately 12% of the Canadian population uses private wells for daily water consumption; however, well water testing rates are on the decline, resulting in an increased risk of waterborne acute gastrointestinal illness. To date, limited research has explored the determinants influencing well testing practices. Accordingly, the current study sought to investigate the drivers of "one-off" and repeat well water testing in southern Ontario during the 5-year period 2012-2016, using the worlds largest private groundwater testing data-frame. Data from >400,000 wells were geospatially integrated with all tests conducted by the provincial laboratory in southern Ontario. The Ontario Marginalization Index (ON-Marg) was used as a proxy measure of socioeconomic status (SES), with rurality, based on population density, season, and index (1st) test results assessed as effect modifiers. Multivariate analysis was undertaken using log-binomial regression. Approximately 27.5% of wells (n = 417,406) were tested during the study period, 66.7% of which were sampled more than once; 3% of all samples tested positive for E. coli (>0 colony forming unit/100 mL). In rural regions (<150 people/km²), wells located in low SES areas were 13% more likely to be tested compared to high SES areas (95% CI: 1.11, 1.15). In urban (>400 people/km²) and peri-urban regions (>150 and <400 people/km²), wells located in low SES areas were 14% (95% CI: 0.78, 0.95) and 15% (95% CI: 0.76, 0.94) less likely to be tested compared to high SES areas. Wells located in low SES areas were 6% more likely to be re-tested (95% CI: 1.04, 1.07). Positive index tests were associated with a 17% increased likelihood of repeat testing (95% CI: 1.16, 1.18). Accordingly, the authors conclude that location and SES are significant predictors of well water testing, with index test status being the most influential predictor of repeat well testing.

Knowledge and behavioural interventions to reduce human health risk from private groundwater systems: A global review and pooled analysis based on development status

Groundwater contamination constitutes a significant health risk for private well users residing in rural areas. As the responsibility to safeguard rural private domestic groundwater typically rests with non-expert homeowners, interventions promoting risk mitigation and awareness represent the most viable means of preventing supply contamination. However, no global review or pooled analyses of these interventions has been undertaken to date. The current study sought to identify and quantify the performance of private well interventions from 1990 to 2018 via a global systematised review and pooled analysis. The PICO (Population-Intervention-Comparison-Outcome) approach was employed for literature identification. Relevant studies were statistically analysed across two quantitative outcome (performance) types, namely knowledge and behaviour, controlling for intervention characteristics and country development status. Mean behavioural and knowledge attainment across interventions was 53% and 48%, respectively, with interventions in economically developed regions exhibiting higher behavioural outcomes (56% vs. 45%) than those in developing regions. Geographically, interventions were located in southern or southeast Asia (n = 23), North America (n = 15), Central America (n = 1) and Africa (n = 1), with none identified in Australia/Oceania, Europe, or South America. Behavioural outcomes were significantly associated with presence of educational/research coordinator (p = 0.023), with these interventions attaining higher levels of efficacy (+74%) than those implemented by other coordinator types. Findings indicate that instructor-led, practical interventions allied with both large- and local-scale awareness-raising campaigns represent an optimum approach for future private well risk interventions. Subsequent adoption of such interventions may lead to increased levels of private well maintenance and provide a point of reference for myriad water and health communication contexts.

Uranium and arsenic unregulated water issues on Navajo lands

The geologic profile of the western United States lends itself to naturally elevated levels of arsenic and uranium in the groundwater and can be aggravated by mining. The Navajo Nation, located in the American Southwest, is the largest contiguous Native American Nation and has over a 100-year legacy of hard rock mining. Concentrations of uranium and arsenic above drinking water standards in unregulated water sources pose various human-health risks to the Navajo Nation due to the lack of public water infrastructure that exists. Although high natural background concentrations may occur in some environments, anthropogenic contamination concerns are especially troublesome for the Navajo Nation, where past uranium mining activity and natural sources affect unregulated water supplies. Community engaged research on uranium and arsenic present in unregulated water wells in the western portion of the Navajo Nation has been a focus of the Ingram laboratory since 2003. These studies have provided important information, particularly for uranium and arsenic, to the communities and the Navajo tribal leaders.

Dissolved Uranium and Arsenic in Unregulated Groundwater Sources - Western Navajo Nation

Concentrations of dissolved uranium (U) and arsenic (As) above drinking water standards in unregulated water sources pose various human health risks. Although high natural background concentrations may occur in some environments (Runnells et al. 1992), anthropogenic contamination concerns are especially troublesome on the Navajo Nation (NN), where past U mining activity may have contaminated water supplies. This research investigated U and As groundwater contamination issues in unregulated wells in the western portion of the NN. Objectives of this research were to provide insights to human health risks by assessing the spatial extent and seasonal variability of U and As concentrations while effectively communicating the potential contamination risks to the local Navajo people. Eighty-two unregulated wells were sampled in 2018; nine of these sources exceeded the maximum contaminant level (MCL) for drinking water standards for U (30 μg/L), and 14 exceeded the MCL for drinking water standards for As (10 μg/L). U and As levels were highest in the southwest portion of the study area and seasonal variability was observed in a subset of wells, especially shallower hand dug wells and hand pumps. The results were compiled into a report that was presented to NN chapters included in the study as well as the Navajo Department of Water Resources and the NN Environmental Protection Agency. Implications for regional water quality patterns can help to direct policy recommendations for well monitoring, water use, and remediation targets.

Risk Communication and Factors Influencing Private Well Testing Behavior: A Systematic Scoping Review

Unregulated private wells may be at risk for certain types of contamination associated with adverse health effects. Well water testing is a primary method to identify such risks, although testing rates are generally low. Risk communication is used as an intervention to promote private well testing behavior; however, little is known about whether these efforts are effective as well as the mechanisms that influence effectiveness. A systematic scoping review was conducted to evaluate the current evidence base for risk communication effectiveness and factors that influence well testing behavior. The review was conducted with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) framework. Data were synthesized using a health behavior model (Health Belief Model) to identify areas amenable to intervention and factors to consider when designing risk communication interventions. We identified a significant shortage of studies examining the effectiveness of risk communication interventions targeted to well testing behavior, with only two quasi-experimental studies identified. The review also identified seventeen studies that examined or described factors relating to well testing behavior. The two empirical studies suggest risk communication methods can be successful in motivating private well owners to test their water, while the remaining studies present considerations for developing effective, community-specific content.

Well water testing in African-American communities without municipal infrastructure: Beliefs driving decisions

Some peri-urban African-American communities in North Carolina remain excluded from nearby municipal water service, forcing them to rely on unregulated private wells. Despite evidence of elevated drinking water contamination risks in these communities, water monitoring is rare. To identify factors influencing decisions to test private wells, we developed and administered a survey to residents of affected areas. A factor analysis identified three constructs significantly associated with a decreased likelihood of water testing: (1) the misconception that contaminants can be detected by sensory perception, (2) concerns about costs of testing and/or water treatment, and (3) not knowing how to get a water test or having time to do so. Increased knowledge about how to test and the importance of testing was significantly associated with a decreased concern about costs which, in turn, was significantly associated with an increased odds of testing. These results suggest the need for targeted risk communications that correct the misperception that contaminants can be tasted, smelled, or seen. The results also suggest the need for clear information about how to get a water test and for low-cost testing programs. Increased monitoring could empower residents to take protective actions and potentially mobilize political support for water service extensions.

Factors influencing perceptions of private water quality in North America: a systematic review

BACKGROUND

An estimated four million and 43 million people in Canada and the USA use private water supplies. Private water supplies are vulnerable to waterborne disease outbreaks. Private water supplies in Canada and the USA are often unregulated and private water management is often a choice left to the owner. Perceptions of water quality become important in influencing the adoption of private water stewardship practices, therefore safeguarding public health.

METHODS

We conducted a systematic literature review to understand factors that shape perceptions of water quality among private water users. We searched six computer databases (Web of science, Medline, Scopus, EBSCO, PubMed and Agricola). The search was limited to primary peer-reviewed publications, grey literature and excluded conference proceedings, review articles, and non-peer review articles. We restricted the search to papers published in English and to articles which published data on surveys of private water users within Canada and the USA. The search was also restricted to publications from 1986 to 2017. The literature search generated 36,478 records. Two hundred and four full text were reviewed.

RESULTS

Fifty-two articles were included in the final review. Several factors were found to influence perceptions of water quality including organoleptic preferences, chemical and microbiological contaminants, perceived risks, water well infrastructure, past experience with water quality, external information, demographics, in addition to the values, attitudes, and beliefs held by well owners.

CONCLUSIONS

Understanding the factors that shape perceptions of water quality among private water users is an important step in developing private water management policies to increase compliance towards water testing and treatment in Canada and the USA. As many jurisdictions in Canada and the USA do not have mandatory private water testing or treatment guidelines, delineating these factors is an important step in informing future research and guiding policy on the public health of private water systems.

State-Level Policies Concerning Private Wells in the United States

Currently, no federal policies exist in the United States regarding private wells; this authority is devolved to states. This study inventoried state-level policies governing private wells in the United States in order to identify the topics addressed by each state, division of responsibilities across state agencies, and geographic differences in policy comprehensiveness. From May to August 2016, two independent reviewers conducted an online search followed by directly contacting state agencies (98% response) to identify all state-level policies in the United States that directly reference private wells. The search, updated in April 2018, confirmed the existing water policy list and identified 23 additional policies. Policies were then coded according to nine not-mutually-exclusive classifications. The results indicate that all states had at least one policy addressing private well drilling or construction. Significant geographic differences exist in maintenance-related policies. In conclusion, although drilling and construction safety are addressed by each state, some policy domains are addressed inconsistently across states, and other policy domains are absent in most states.

Development and Validation of an Environmental Health Literacy Assessment Screening Tool for Domestic Well Owners: The Water Environmental Literacy Level Scale (WELLS)

In the U.S., privately owned wells are not subject to any regulatory testing requirements. Well owners must have sufficient environmental health literacy (EHL) to understand and interpret information that contain complex terms and labels to manage their water quality. The objective of this paper is to assess the performance and validity of a new EHL screening tool. The Water Environmental Literacy Level Scale (WELLS) is based on the Newest Vital Sign (NVS) and contains six questions on comprehension, calculations and application of information. Content validity was assessed from expert review. Criterion-related and construct validity were evaluated using an online, convenience sample of adults (n = 869). Percent of correct responses for items ranged from 53% to 96% for NVS and from 41% to 97% for WELLS. Completion time, mean scores, distributions, and internal consistency were equivalent between both scales. Higher scores suggest higher EHL. The scales were moderately correlated (ρ = 0.47, p < 0.001). Kappa agreement was 74%. Bland-Altman plots depicted little mean difference between the scales. Education and income level were positively associated with EHL. WELLS showed criterion-validity with NVS and construct validity with education and income. In practice or research, WELLS could quickly screen individuals for low EHL.

The Strong Heart Water Study: Informing and designing a multi-level intervention to reduce arsenic exposure among private well users in Great Plains Indian Nations

Elevated arsenic exposure from drinking water is associated with an increased risk of cardiovascular disease, diabetes, kidney disease, and skin, lung, and bladder cancer. Arsenic contamination in groundwater supplies disproportionately affects rural populations using private wells. Arsenic mitigation programs for American Indian communities are limited. There is an urgent need for targeted approaches to reduce arsenic exposure for at-risk communities using private wells. Formative research was conducted to inform and design a community-based arsenic mitigation intervention for Lakota and Dakota Nations in the Great Plains Area of the United States, where, in some communities, one-quarter of private wells are estimated to have elevated arsenic. Formative research included semi-structured interviews, a community workshop, intervention-planning workshops, and a pilot study of the developed intervention. Community members prioritize aesthetic qualities of water (e.g. taste, color), safety, and other situational factors (e.g. cost) when considering their drinking and cooking water. Although water safety is a concern, awareness and concern for arsenic vary substantially within communities. To reduce arsenic exposure, community members recommended communication of water test results, home visits for intervention delivery, and reminders to use arsenic-safe water. Findings informed the development of an intervention to prevent arsenic exposure through drinking water and cooking, including health promotion messages and household items to facilitate use of an arsenic removal device (e.g. tankards to store filtered water). The pilot study indicated promising acceptability and operability of the developed intervention. This research provides a model for the development of environmental health interventions in partnership with American Indian and other private well-using communities.