Lead Service Lines Research Articles

Assessing the sustainability and safety of polyethylene terephthalate (PET) liners for lead service lines (LSL) upgrades

Polyethylene Terephthalate (PET) liners have been proposed by industry as a more cost effective and less disruptive alternative to lead service lines (LSL) replacement. However, concerns have been raised about their aging under real-use conditions and their potential health and environmental impacts. In this study, two approaches were implemented. First, bench and pilot scale experiments were carried out to investigate the aging of a PET liner under conditions that simulate normal usage. Results show early surface oxidation and leaching of potentially hazardous metals (lead, zinc and titanium). No short-term fragmentation of the PET liner into microplastics was observed. Next, a life cycle assessment (LCA) compared the health and environmental impacts of three LSL upgrade alternatives: PET liners and full LSL replacement using either copper or PEX pipes. The installation phase was shown to be the main contributor to impact scores, while the benefits of PET liners are highly dependent on their lifespan. PEX pipes installed by torpedoing lower impacts as compared to PET liners and copper pipes for equal lifespan, while the use of PET liners remains less impactful regarding human health and ecosystem quality when a complete excavation is needed. LCA derived global human health effects due to ingestion of leached metals from PET liners, copper pipes and unreplaced LSL, and showed that PET liners and copper pipes significantly reduce health impacts by 14 and 80 DALY respectively compared to unreplaced LSL. Finally, the Integrated Exposure Uptake Biokinetic (IEUBK) model was used to assess the impact of lead exposure specifically for drinking water ingestion. Estimated Blood Lead Levels (BLL) in children and infants in households with long unreplaced LSL was up to 263.7% and 207.8% greater compared to either replacement with copper pipes or rehabilitation with PET liners, showing the clear benefits of corrective action. Combining experimental results, LCA and biokinetic modeling provides actionable information for utilities to select the best upgrade options, considering environmental, health and practical constraints, whilst identifying remaining data gaps. The relative benefits of PET liners should be carefully evaluated considering their lifespan under real-life conditions, the complete replacement costs after failure, and the growing evidence of micro- and nanoplastics (MNP) risks.

Developing Service Line Inventories: Guidance for Utilities With Limited Lead Lines

Key TakeawaysIn the United States, all community and nontransient noncommunity water systems are required to submit an inventory describing the location and makeup of all service lines in their service areas.While the material can be designated as lead, galvanized requiring replacement, nonlead, or unknown, the last two designations require additional steps to be taken in the proposed Lead and Copper Rule Improvements (LCRI).Some utilities have few or no lead service lines, and this inventory requirement, issued by the US Environmental Protection Agency (EPA), may be burdensome to those utilities.This article demonstrates the methodology in EPA's proposed LCRI for verification of construction material, and an alternate validation procedure is proposed.

Estimating the impact of the proposed Lead and Copper Rule Improvements

AbstractLead in drinking water can lead to serious health effects, including neurodevelopmental issues and heart disease. In December 2023, the U.S. Environmental Protection Agency (EPA) proposed the Lead and Copper Rule Improvements (LCRI), which lower the Lead and Copper Rule's (LCR's) lead action level (AL) from 15 parts per billion (ppb) to 10 ppb and require both first‐ and fifth‐liter sampling and 90th percentile compliance calculations based on the highest lead levels at sites with lead service lines. A methodology for estimating the likelihood a system will have an AL exceedance (ALE) under the LCRI was developed using Michigan LCR compliance data and applied to national LCR compliance data. Findings were compared to EPA's estimates, indicating EPA may have underestimated the percent of smaller systems (serving 3300) with ALEs and overestimated the percent of larger systems (serving > 10,000), thus underestimating costs and overestimating the benefits of this rulemaking.

The use of lead isotopes for determining sources of lead in drinking water

AbstractA series of paired samples were analyzed to determine if high‐precision lead isotopic fingerprinting could help identify the source of lead in plumbing materials and drinking water. Samples were obtained of plumbing materials (lead service lines, copper pipe with lead solder, galvanized materials, and brass fixtures) from water utilities across the United States. Lead samples were taken from the material itself, from scales, and in some cases from associated water. The lead samples were analyzed to determine the ratios of the four stable lead isotopes present. The results enabled the identification of relationships between various components and further aided in the identification of the source of lead found in water and in pipe scales. Isotopic fingerprinting, as demonstrated in this study, could be used to determine if a galvanized line is a galvanized line requiring replacement (GRR) under the Lead and Copper Rule Improvements (USEPA, 2023).

Review of historical plumbing codes for lead service line inventories in the United States

ABSTRACT Inventorying and replacing lead service lines (LSLs) is a national priority in the United States (US), with records review conducted as a first step. Among other records, historical plumbing codes can provide cutoff dates for LSL allowance in the US. This work identified and reviewed historical national plumbing codes for mention of lead for drinking water pipe and found that lead pipe was permissible for service lines by the Basic Plumbing Code until 1978, the Uniform Plumbing Code until 1988, and the Southern Standard Plumbing Code until 1977/78. Overall, identifying pertinent code titles over time and obtaining them was challenging because those records were not readily available. Once obtained, interpreting the code language also proved challenging. Terminology initially reflected sanitary systems before drinking water systems were incorporated, and code editions through the years reorganized the content and specific mentions of lead in service lines within text. This review focused on model plumbing codes, which are then adopted at the state or local level, typically with modifications that also need to be understood. Two practical examples of service line inventory development were also summarized. These examples highlighted placing different emphasis on plumbing code review.

Estimated Childhood Lead Exposure From Drinking Water in Chicago

There is no level of lead in drinking water considered to be safe, yet lead service lines are still commonly used in water systems across the US. To identify the extent of lead-contaminated drinking water in Chicago, Illinois, and model its impact on children younger than 6 years. For this cross-sectional study, a retrospective assessment was performed of lead exposure based on household tests collected from January 2016 to September 2023. Tests were obtained from households in Chicago that registered for a free self-administered testing service for lead exposure. Machine learning and microsimulation were used to estimate citywide childhood lead exposure. Lead-contaminated drinking water, measured in parts per billion. Number of children younger than 6 years exposed to lead-contaminated water. A total of 38 385 household lead tests were collected. An estimated 68% (95% uncertainty interval, 66%-69%) of children younger than 6 years were exposed to lead-contaminated water, corresponding to 129 000 children (95% uncertainty interval, 128 000-131 000 children). Ten-percentage-point increases in block-level Black and Hispanic populations were associated with 3% (95% CI, 2%-3%) and 6% (95% CI, 5%-7%) decreases in odds of being tested for lead and 4% (95% CI, 3%-6%) and 11% (95% CI, 10%-13%) increases in having lead-contaminated drinking water, respectively. These findings indicate that childhood lead exposure is widespread in Chicago, and racial inequities are present in both testing rates and exposure levels. Machine learning may assist in preliminary screening for lead exposure, and efforts to remediate the effects of environmental racism should involve improving outreach for and access to lead testing services.

Factors Influencing Customer Participation in a Program to Replace Lead Pipes for Drinking Water.

Many public water systems are struggling to locate and replace lead pipes that distribute drinking water across the United States. This study investigates factors associated with customer participation in a voluntary lead service line (LSL) inspection and replacement program. It also uses quasi-experimental and experimental methods to evaluate the causal impacts of two grant programs that subsidized homeowner replacement costs on LSL program participation. LSLs were more prevalent in areas with a higher concentration of older housing stock, Black and Hispanic residents, renters, and lower property values. Owner-occupied and higher valued properties were more likely to participate in the LSL program. Results from the two grant program evaluations suggest that subsidies for low-income homeowners to cover LSL replacement costs can significantly boost participation, but only when the programs are well publicized and easy to access. Even then, there was still significant non-participation among properties with confirmed LSLs.

An evaluation of properly operated NSF/ANSI-53 Pb certified drinking water filters in Benton Harbor, MI.

Communities across the United States and particularly in the Midwest continue to grapple with the complications associated with aging infrastructure. This includes the presence of lead (Pb)-bearing plumbing components such as lead service lines, downstream galvanized iron pipes, and Pb/tin solder. The community of Benton Harbor, MI, experienced six Pb action level exceedances between 2018 and 2021, leading to increasing community concern and a request from the state of Michigan for the US Environmental Protection Agency involvement. Between 9 November and 17 December 2021, US EPA Region 5 and Office of Research and Development, along with the state of Michigan, conducted a water filter efficacy and Pb-nanoparticulate (<100 nm) study to evaluate the performance of NSF/ANSI-53 Pb-certified drinking water filters and the presence of nanoparticulate. In this study, a total of 199 properly installed and operated drinking water filters (combination of faucet mounted and pitcher) were tested in their residential locations. One hundred percent of the water filters were found to perform to the standard to which they were certified, with filtered drinking water Pb concentrations below 5 ppb (maximum observed was 2.5 ppb). In addition, Pb particulate was identified; however, discrete Pb-containing nanoparticles were not widely found or identified.

Got Lead in Your Water? The Bipartisan Infrastructure Law May Be Poised to Help

Humans have no known safe level of exposure to lead. Blood lead levels have devastating consequences, especially for children, affecting their brain development and almost every organ in their bodies. Various government organizations have enacted measures to combat lead contamination in drinking water and its dangerous human health consequences by replacing lead service lines. At the federal level, the Environmental Protection Agency promulgated the Lead and Copper Rule Revisions, which requires states to replace lead service lines. At the state level, governments have programs to fund the replacement of lead service lines in their communities, but these funds often fall short of their needs. While these efforts have reduced the problem of lead contamination in drinking water, many of the remaining lead service lines in the U.S. are found buried under aging cities, often with low-income populations. Litigation brought by public interest groups has spurred faster replacement, but this has only been deployed in a handful of cities. The greater leverage point is increased federal funding to eradicate the problem. In 2021, the U.S. Congress passed the Bipartisan Infrastructure Law, signed by President Biden. It included a historically large increase in supplemental funds for the replacement of lead service lines over five years. In early 2023, the Biden-Harris Administration announced a campaign to get lead out of water and accelerate the pace of the solutions. This article examines the scope of the problem of replacing lead service lines in states in the Great Lakes region, the cost estimates of financing their replacement, and the decisions states need to make now to access and effectively spend federal money from the Bipartisan Infrastructure Law to remove lead from the water of the nation’s disadvantaged communities.

Finding and Assessing US Galvanized Service Lines

Given impending regulations, a study of community water systems found challenges in defining, identifying, and funding remediation of the galvanized pipe associated with lead service lines.

Electrochemical Method for Detection and Quantification of Lead Particulate in Tap Water

Quantification of lead particulates requires laborious sample acidification and/or digestion in acidic environment, therefore lead quantification is limited to laboratories with trained personnel and expensive instrumentation. These technologies are not easily accessible to the public, and the large number of portable methods available to public today are characterized by their qualitative nature, and requirement of additional reagents. Unlike labor intense expensive instruments, electrochemical methods are inexpensive, fast and portable but they are blind to non-electroactive lead species or particulate forms of lead. They are limited to the detection of ionic or electroactive analytes. This talk will report an electrochemical method for the detection and quantification of lead contaminant in drinking waters that results from particulate forms of lead, mostly present as scales. We will present the fundamentals of membrane electrolysis for reagent-free sample preparation and detection of Pb2+. Also, we will present the characterization of real particulates/scales extracted from lead service lines from the Cincinnati area. We think this method will contribute to the development of on-site, quantitative methods of lead detection, and can assist to the research and understanding of drinking water contamination. Perhaps it could help to determine what triggers lead intermittent release to residential tap water. This work has the potential to address the lack of that instrumentation because it employs a robust technology based on anionic exchange membrane and controlled electrolysis for in-situ generation of nitric acid, that eliminates the need of external reagent or sample treatments. For its trace detection, it employs a well stablished Anodic Striping Voltammetry method.

Predictive Modeling in Service Line Inventory Development

Key TakeawaysAcceptance of predictive modeling as a verification method in inventories complying with the Lead and Copper Rule Revisions is determined by individual states, many of which accept this approach.Predictive modeling is an accurate, time‐saving, economical way to reduce unknowns in the inventory and streamline lead service line replacement.For the best outcomes, the performance and reliability of predictive models must be evaluated carefully and from multiple perspectives.

Digging into Exposure Disparities: Mapping Lead Service Lines in New York City.

Digging into Exposure Disparities: Mapping Lead Service Lines in New York City.

Development and optimization of a systematic approach to identifying lead service lines: One community's success

Lead service lines (LSLs), when present, are the largest source of lead in drinking water, and their removal is necessary to reduce public exposure to lead from drinking water. Unfortunately, the composition of many service lines (SLs) is uncertain. The town of Bennington, Vermont, for example, has unreliable SL records, making it challenging to build an inventory and conduct an LSL replacement program. In 2017, Bennington commenced a project to identify SL materials and replace all LSLs. 159 control homes, consisting of 99 LSL and 60 non-LSL sites, were chosen for record reviews, visual SL observations, fully flushed (FF) and sequential profile water sampling, and test excavations to evaluate method accuracies. Of the 159 control homes, records for 90 % of the 99 known LSL homes were accurate. Whereas 3 % of the 60 non-lead SL homes’ records accurately identified SL material. Fully flushed and sequential profile samples (SPSs) were 73 % and 95 % accurate for identifying LSLs and 95 % and 83 % accurate for identifying non-LSLs, respectively. Results were 100 % accurate when visual observations, FF samples, and test excavation were used in a stepwise approach. A stepwise approach consisting of visual SL observations, FF samples, and SPSs achieved a 98 % accuracy at identifying LSLs and a 67 % cost reduction compared to performing test excavations at each home. Findings from this control group study are critical for state, tribal, and local officials to inform their decisions about the selected approach to identify unknown SLs.

Benton Harbor: From Lead Crisis to Lead‐Free

Key TakeawaysA community effort in Benton Harbor, Mich., drew attention to the lack of public education about lead levels in water and highlighted the need for lead service line replacement.The state and the US Environmental Protection Agency responded quickly to a community petition to address the lead crisis and involved the community in the response.In 11 months, 99% of Benton Harbor's service lines had been replaced or confirmed as non‐lead, while residents received information and solutions to ensure they had safe drinking water.

Geospatial Assessment of Racial/Ethnic Composition, Social Vulnerability, and Lead Water Service Lines in New York City.

The state of New York expects to receive in 2022 alone from the U.S. Infrastructure Investment and Jobs Act to support the replacement of lead water service lines. Our objective was to determine the number and proportion of potential lead water service lines across New York City (NYC) and to evaluate the association between census tract-level racial/ethnic composition, housing vulnerability, and child lead exposure vulnerability with service line type (Potential Lead, Unknown) for NYC tracts. We conducted a descriptive analysis assessing water service line material recorded in the NYC Department of Environmental Protection's Lead Service Line Location Coordinates database. We used conditional autoregressive Bayesian Poisson models to assess the relative risk [RR; median posterior estimates, and 95% credible interval (CrI)] of service line type per 20% higher proportion of residents in a given racial/ethnic group and per higher housing vulnerability and child lead exposure vulnerability index scores corresponding to the interquartile range. We also evaluated the associations in flexible natural cubic spline models. Out of 854,672 residential service line records, 136,891 (16.0%) were Potential Lead, and 227,443 (26.6%) were Unknown. In fully adjusted models, higher proportions of Hispanic/Latino residents and higher child lead exposure vulnerability were associated with Potential Lead service lines in flexible spline models and linear models [ (95% CrI: 1.11, 1.21) and (95% CrI: 1.02, 1.20), respectively]. Associations were modified by borough; Potential Lead service lines were associated with higher proportions of non-Hispanic White and non-Hispanic Asian residents in the Bronx and Manhattan, and with higher proportions of non-Hispanic Black residents in Queens. NYC has a high number of Potential Lead and Unknown water service lines. Communities with a high proportion of Hispanic/Latino residents and those with children who are already highly vulnerable to lead exposures from numerous sources are disproportionately impacted by Potential Lead service lines. These findings can inform equitable service line replacement across New York state and NYC. https://doi.org/10.1289/EHP12276.

Removing Michigan's Lead Water Service Lines: Economic Savings, Health Benefits, And Improved Health Equity.

Michigan's recently revised Lead and Copper Rule requires water utilities to inventory existing water service lines by 2025 and replace all lead-containing lines by 2041. This article summarizes a cost-benefit analysis using new inventory data on the number of lead service lines in the state, the projected cost of their replacement, and the estimated lifetime benefits from reduced lead exposure. Replacing 423,479 lead service lines would reduce lead exposure for 420,800 newborns and result in $3.24billion in future benefits (compared with replacement costs of $1.33billion). This would generate net savings of $1.91billion and a societal return on investment of $2.44 per dollar invested. These estimates are conservative and include only quantified benefits for newborn children in Michigan for the period 2020-60. More than 153,100 of the children benefiting would be non-White (of whom 78,400 would be Black or African American), and 106,900 would be in households with incomes below the federal poverty level. Sensitivity analyses show that accelerating the replacement pace would increase the societal return on investment. This primary prevention-driven policy has the potential to reduce childhood lead exposure and improve health equity.

Planning for Service Line Material Identification and Lead Service Line Replacement Costs

Key TakeawaysA utility survey was performed to gather cost data and information on identification and verification methods.In compiling a service line inventory, water utilities need to account for using multiple verification methods at some locations to improve accuracy.Costs vary significantly between verification methods for developing accurate service line inventories and should be accounted for in a water system's planning efforts.The costs for lead service line replacements are estimated to be higher than originally reported when accounting for auxiliary costs to utilities.

Effect of stagnation period and flow rate on soluble and particulate Pb leaching in copper pipe water distribution systems

Extremely high lead level in tap water caused by particulates has attracted increasing attention in recent years. Despite extensive research on the role of particulate Pb in water supply systems with lead service lines, little information is available on the role of particulate Pb in copper (Cu) water distribution systems. In this study, the dissolved, colloidal, and particulate lead and copper concentrations in representative prototype copper pipe water distribution systems with leaded solder joints and brass fixtures are measured. The effects of flow rate and stagnation time on metal fractionation are investigated. For each experimental scenario, all the water that stagnated inside the system is sampled to have a comprehensive understanding of lead contamination. Sampled at flow rates of 200–250 mL/s, the soluble lead and copper make up 60–96 % of the total concentration in the samples after hours of stagnation. More than half of the Pb and Cu particles are larger than 0.8 μm. Higher flow rates result in substantial increases in particulate metal concentrations but have no apparent effect on dissolved metals. The soluble and particulate copper concentrations (∼ 100–250 μg/L) both increase with stagnation time. For the case of Pb, while the particulate concentration increases (up to ∼ 40 μg/L after 12 h), the soluble concentration does not change significantly beyond 4 h; this can be attributed to the different solubilities of Pb (∼ 20 μg/L) and Cu (∼ 200 μg/L) in tap water. The results also show that particulates suspended by clean “once through” water (without prior stagnation) can lead to high levels of Pb contamination (> 10 μg/L).

Reduction in water consumption in premise plumbing systems: Impacts on lead concentration under different water qualities

Water conservation measures are increasing in response to regulatory requirements addressing the need for lower environmental footprint and in response to water shortages. In households with lead service lines (LSLs), lowering consumption can adversely impact lead release as it will increase stagnation. Using a lead dissolution model and data from extensive pilot studies on excavated LSLs, the impact of adaptation to different water conservation strategies on dissolved lead contamination at the kitchen tap is assessed under three water qualities and three LSL lengths (3, 14 and 30 m) using hydraulic and water quality modelling. Consumers' behavioural variability is also assessed based on integration of EPANET and results of the stochastic water demand model SIMDEUM. Demand reduction increased the dissolved lead concentrations (Pbdiss) at the end of the LSL with mean values ranging from 28.4 to 63.3 μg/L (without corrosion control) and from 4.6 to 9.9 μg/L with corrosion control (addition of orthophosphate and pH adjustment). Adding orthophosphate (1 mg P/L) to the water reduces the mean Pbdiss values at the kitchen tap from 7.1 μg/L to 1.2 μg/L for a high water demand scenario and from 31.2 to 4.9 μg/L for a low water demand scenario. Finally, the Integrated Exposure Uptake Biokinetic (IEUBK) model is used to predict the potential blood lead levels (BLLs) for children aged 0–84 months. Results showed that the orthophosphate addition of only 1 mg P/L can significantly decrease the proportion of children with a BLL >5 μg/dL, from 82 % to 17 %, under the most extreme water conservation scenario studied, using the 90th percentile of Pbdiss concentrations during usage at kitchen tap. Wide variations of Pbdiss concentrations at the kitchen tap were calculated at times of use over a week (up to 155 μg/L in lower demand scenarios, without corrosion control) showing evident limitations of single random daytime sampling.