Kelsey J. Pieper

Incidence of waterborne lead in private drinking water systems in Virginia

Although recent studies suggest contamination by bacteria and nitrate in private drinking water systems is of increasing concern, data describing contaminants associated with the corrosion of onsite plumbing are scarce. This study reports on the analysis of 2,146 samples submitted by private system homeowners. Almost 20% of first draw samples submitted contained lead concentrations above the United States Environmental Protection Agency action level of 15 μg/L, suggesting that corrosion may be a significant public health problem. Correlations between lead, copper, and zinc suggested brass components as a likely lead source, and dug/bored wells had significantly higher lead concentrations as compared to drilled wells. A random subset of samples selected to quantify particulate lead indicated that, on average, 47% of lead in the first draws was in the particulate form, although the occurrence was highly variable. While flushing the tap reduced lead below 15 μg/L for most systems, some systems experienced an increase, perhaps attributable to particulate lead or lead-bearing components upstream of the faucet (e.g., valves, pumps). Results suggest that without including a focus on private as well as municipal systems it will be very difficult to meet the existing national public health goal to eliminate elevated blood lead levels in children.

Strategies to improve private-well water quality: A North Carolina perspective

Background: Evidence suggests that the 44.5 million U.S. residents drawing their drinking water from private wells face higher risks of waterborne contaminant exposure than those served by regulated community water supplies. Among U.S. states, North Carolina (N.C.) has the second-largest population relying on private wells, making it a useful microcosm to study challenges to maintaining private-well water quality. Objectives: This paper summarizes recommendations from a two-day summit to identify options to improve drinking-water quality for N.C. residents served by private wells. Methods: The Research Triangle Environmental Health Collaborative invited 111 participants with knowledge of private-well water challenges to attend the Summit. Participants worked in small groups that focused on specific aspects and reconvened in plenary sessions to formulate consensus recommendations. Discussion: Summit participants highlighted four main barriers to ensuring safe water for residents currently relying on private wells: (1) a database of private well locations is unavailable; (2) racial disparities have perpetuated reliance on private wells in some urbanized areas; (3) many private-well users lack information or resources to monitor and maintain their wells; and (4) private-well support programs are fragmented and lack sufficient resources. The Summit produced 10 consensus recommendations for ways to overcome these barriers. Conclusions: The Summit recommendations, if undertaken, could improve the health of North Carolinians facing elevated risks of exposure to waterborne contaminants because of their reliance on inadequately monitored and maintained private wells. Because many of the challenges in N.C. are common nationwide, these recommendations could serve as models for other states. https://doi.org/10.1289/EHP890

Evaluating Water Lead Levels During the Flint Water Crisis

In April 2014, the drinking water source in Flint, Michigan was switched from Lake Huron water with phosphate inhibitors to Flint River water without corrosion inhibitors. The absence of corrosion control and use of a more corrosive source increased lead leaching from plumbing. Our city-wide citizen science water lead results contradicted official claims that there was no problem- our 90th percentile was 26.8 μg/L, which was almost double the Lead and Copper Rule action level of 15 μg/L. Back calculations of a LCR sampling pool with 50% lead pipes indicated an estimated 90th percentile lead value of 31.7 μg/L (±4.3 μg/L). Four subsequent sampling efforts were conducted to track reductions in water lead after the switch back to Lake Huron water and enhanced corrosion control. The incidence of water lead varied by service line material. Between August 2015 and November 2016, median water lead reduced from 3.0 to <1 μg/L for homes with copper service lines, 7.2-1.9 μg/L with galvanized service lines, and 9.9-2.3 μg/L with lead service lines. As of summer 2017, our 90th percentile of 7.9 μg/L no longer differed from official results, which indicated Flints water lead levels were below the action level.

America’s Path to Drinking Water Infrastructure Inequality and Environmental Injustice: The Case of Flint, Michigan

Much of America’s aging drinking water infrastructure is in a state of disrepair that threatens our water quality and public health. If the goal of equitable access to safe water is to be realized, we must rise to the challenge of replacing or upgrading this infrastructure starting in communities that can least afford to do so. This chapter examines the disparate financial burdens, potential health impacts, and environmental justice implications that water infrastructure inequality poses through the problem of lead in drinking water and opportunistic premise plumbing pathogens. The lead-in-water crisis and Legionella outbreak in Flint, Michigan, provides a clarion call to address funding needs, strengthen regulations, incentivize regulatory compliance, promote meaningful public participation, ensure government accountability, and improve public health outcomes.

Effectiveness of Prevailing Flush Guidelines to Prevent Exposure to Lead in Tap Water

Flushing tap water is promoted as a low cost approach to reducing water lead exposures. This study evaluated lead reduction when prevailing flush guidelines (30 s–2 min) are implemented in a city compliant with lead-associated water regulations (New Orleans, LA, USA). Water samples (n = 1497) collected from a convenience sample of 376 residential sites (2015–2017) were analyzed for lead. Samples were collected at (1) first draw (n = 375) and after incremental flushes of (2) 30–45 s (n = 375); (3) 2.5–3 min (n = 373), and (4) 5.5–6 min (n = 218). There was a small but significant increase in water lead after the 30 s flush (vs. first draw lead). There was no significant lead reduction until the 6 min flush (p < 0.05); but of these samples, 52% still had detectable lead (≥1 ppb). Older homes (pre-1950) and low occupancy sites had significantly higher water lead (p < 0.05). Each sample type had health-based standard exceedances in over 50% of sites sampled (max: 58 ppb). While flushing may be an effective short-term approach to remediate high lead, prevailing flush recommendations are an inconsistently effective exposure prevention measure that may inadvertently increase exposures. Public health messages should be modified to ensure appropriate application of flushing, while acknowledging its short-comings and practical limitations.

Elevated Lead in Water of Private Wells Poses Health Risks: Case Study in Macon County, North Carolina

Recent research has indicated that lead in water of private wells is in the range of that which caused problems in Flint, Michigan. However, there is limited understanding of the mechanisms for water lead release in these systems. We evaluated water lead at the homes of two children with elevated blood lead in Macon County (North Carolina), which did not have identifiable lead paint or lead dust hazards, and examined water lead release patterns among 15 private wells in the county. Water lead release patterns differed among the 15 private wells. Problems with lead release were associated with (1) dissolution of lead from plumbing during periods of stagnation; (2) scouring of leaded scales and sediments during initial water use; and (3) mobilization of leaded scales during continued water use. Accurate quantification of water lead was highly dependent on sample collection methods, as flushing dramatically reduced detection of lead hazards. The incidence of high water lead in private wells may be present in other counties of North Carolina and elsewhere in the United States. The underestimation of water lead in wells may be masking cases of elevated blood lead levels attributed to this source and hindering opportunities to mitigate this exposure.