Arsenic in private well water part 2 of 3: Who benefits the most from traditional testing promotion?

Arsenic, a toxic element naturally found in groundwater, is a public health concern for households drinking from wells. Private well water is not regulated to meet the federal drinking water arsenic Maximum Contaminant Level (MCL) of 10µg/L, or the more protective 5µg/L New Jersey (NJ) state MCL. In the absence of consistent private well regulation, public health efforts have relied on promoting testing in affected communities to various degrees of success. Few interventions publish results, and more often focus on the outcome of tested wells rather than who completed a test, and more importantly, who did not. Through our survey of randomly selected addresses (n=670) in 17 NJ towns we find higher rates of arsenic testing in areas with a history of testing promotion. However, we also see a stronger correlation of testing behavior with income and education in high promotion areas, suggesting that community engagement activities may be exacerbating socioeconomic status (SES) testing disparities. Well owners with a bachelor's degree had ten times greater odds of participating in our direct mail testing intervention than those with less education when tests cost $40. After all households (n=255) were offered free tests to overcome many of the usual testing barriers - awareness, convenience, and cost - only 47% participated and those who chose to return water samples were of higher income and education than those who did not. Our findings highlight that while efforts to promote and provide arsenic testing succeed in testing more wells, community testing interventions risk increasing SES disparities if those with more education and resources are more likely to take advantage of testing programs. Therefore, testing interventions can benefit by better targeting socially vulnerable populations in an effort to overcome SES-patterned self-selection when individuals are left alone with the responsibility of managing their drinking water quality.

Arsenic in private well water part 3 of 3: Socioeconomic vulnerability to exposure in Maine and New Jersey.

Arsenic is a naturally occurring toxic element often concentrated in groundwater at levels unsafe for human consumption. Private well water in the United States is mostly unregulated by federal and state drinking water standards. It is the responsibility of the over 13 million U.S. households regularly depending on private wells for their water to ensure it is safe for drinking. There is a consistent graded association with health outcomes at all levels of socioeconomic status (SES) in the U.S. Differential exposure to environmental risk may be contributing to this persistent SES-health gradient. Environmental justice advocates cite overwhelming evidence that income and other SES measures are consistently inversely correlated with exposure to suboptimal environmental conditions including pollutants, toxins, and their impacts. Here we use private well household surveys from two states to investigate the association between SES and risks for arsenic exposure, examining the potentially cumulative effects of residential location, testing and treatment behavior, and psychological factors influencing behavior. We find that the distribution of natural arsenic hazard in the environment is socioeconomically random. There is no evidence that higher SES households are avoiding areas with arsenic or that lower SES groups are disproportionately residing in areas with arsenic. Instead, disparities in exposure arise from differing rates of protective action, primarily testing well water for arsenic, and secondly treating or avoiding contaminated water. We observe these SES disparities in behavior as well as in the psychological factors that are most favorable to these behaviors. Assessment of risk should not be limited to the spatial occurrence of arsenic alone. It is important that social vulnerability factors are incorporated into risk modeling and identifying priority areas for intervention, which should include strategies that specifically target socioeconomically vulnerable groups as well as all the conditions which cause these disparities in testing and treatment behavior.

Arsenic in private well water part 1 of 3: Impact of the New Jersey Private Well Testing Act on household testing and mitigation behavior.

Regularly ingesting water with elevated arsenic increases adverse health risks. Since September 2002, the NJ Private Well Testing Act (PWTA) has required testing untreated well water for arsenic during real estate transactions in 12 counties. Its implementation provides an opportunity to investigate the effects of policy intervention on well testing and treatment behavior. Here we analyze results of a survey mailed to 1943 random addresses (37% response), including responses from 502 private well households who purchased their homes prior to PWTA commencement and 168 who purchased after. We find the PWTA has significantly increased arsenic testing rates in an area where 21% of wells contain arsenic above the 5µg/L NJ drinking water standard. The PWTA has allowed identification of more wells with arsenic (20% of post-PWTA vs. 4% of pre-PWTA households) and more treatment for arsenic (19% of post-PWTA vs. 3% of pre-PWTA households). Such an Act is a partial answer to significant socioeconomic disparities in testing observed among households for whom it is not required. Additionally residents purchasing homes since 2002 are younger and disproportionately more likely to have children in their household (60% vs. 32%), a priority group given their particular vulnerability to effects of arsenic. Despite more wells tested under the PWTA, post-PWTA well owners forget or misremember arsenic test results more often, are more likely to report not knowing what kind of treatment they are using, and are not reporting better maintenance or monitoring of their treatment systems than pre-PWTA households. This suggests serious challenges to reducing arsenic exposure remain even when testing is a requirement. Furthermore, only a fraction of wells have been tested under the PWTA due to the slow pace of housing turnover. We recommend more public resources be made available to support private well testing among socially and biologically vulnerable groups.