Old Lead Plumbing

Lead service lines or old solder in home plumbing.

42Moderate burden · out of 100

Cleaner swapTest the water, use a filter certified to NSF/ANSI 53 for lead, and replace the lead line

How this score is built

100Start
72.4Chemical hazard 6 × 4.6−27.6
55.4Everyday exposure 5 × 3.4−17
42Persistence 5 × 2.6−13, then rounded to 42
ModerateThe band42 sits in 40–59.

What each input rests on

The three ratings behind the score, and the studies each rests on
Input	Rating	Evidence
Chemical hazard	6/10	In 14,289 US adults followed for a median 19.3 years, a rise in blood lead from 1.0 to 6.7 μg/dL was associated with all-cause mortality (hazard ratio 1.37) and cardiovascular mortality (1.70). Low-level lead exposure and mortality in US adults: a population-based cohort study · Lancet Public Health 2018 DOI 10.1016/S2468-2667(18)30025-2 · PMID 29544878 · Abstract, Findings · read 2026-10-02 Pooling 1,333 children from seven cohorts, a rise in blood lead from 2.4 to 10 μg/dL was associated with a 3.9-point IQ decrement (95% CI 2.4–5.3). Low-level environmental lead exposure and children's intellectual function: an international pooled analysis · Environ Health Perspect 2005 DOI 10.1289/ehp.7688 · PMID 16002379 · Abstract · read 2026-10-02
Everyday exposure	5/10	Among 63,854 Washington DC children, lead service lines were an independent risk factor for blood lead of 10 and 5 μg/dL or more, even when the water met the EPA 15 ppb action level. Association between children's blood lead levels, lead service lines, and water disinfection, Washington, DC, 1998-2006 · Environ Res 2011 DOI 10.1016/j.envres.2010.10.003 · PMID 21112052 · Abstract, Results · read 2026-10-02 Across census tracts served by the Cincinnati and Grand Rapids water systems, lead service line prevalence correlated strongly with children’s elevated blood lead (5 μg/dL or more): r = 0.71 and r = 0.83. Strong Association between Children's Elevated Blood Lead Levels and Lead Service Lines: A Census Tract-Level Analysis for Two Midwest Cities · Environ Sci Technol 2025 DOI 10.1021/acs.est.5c06429 · PMID 41118322 · Abstract · read 2026-10-02
Persistence	5/10	After occupational exposure, blood lead declines slowly, with a 5- to 19-year half-life reflecting lead’s long stay in the skeleton; repeated bone measurements show slow elimination of lead from bone. Toxicokinetics of bone lead · Environ Health Perspect 1991 DOI 10.1289/ehp.919133 · PMID 2040248 · Abstract · read 2026-10-02

Ratings are editorial. A study listed here supports the rating; it did not compute it. How the index is built

What this means for you

The chemical-hazard rating is what drives the score down. Lead pipes and solder can leach lead into tap water, and harm has been measured even at low blood-lead levels. Have the water tested, and use a filter certified to NSF/ANSI 53 for lead until the line is replaced.

Evidence strength: strong

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Lower-exposure choices

Reverse-Osmosis Filtered WaterMinimal · Water

Carbon-Filter Pitcher WaterLow · Water

All 8 water entries, highest burden first →