Well Water Research: Peer-Reviewed Studies on Private Wells
A short reading list of peer-reviewed studies about private well water, grouped by topic. Each entry links to the paper on PubMed and gives a one-line plain-English summary.
Find a Well Lab is a directory of certified labs, not a medical or scientific authority. The summaries below are our short readings of each abstract; read the paper itself for the full methods, results and limits. Every citation was checked against PubMed on November 2, 2026. The only way to know what is in your own well is a test from a certified lab in your state.
Bacteria: total coliform and E. coli
- Total coliform and Escherichia coli contamination in rural well water: analysis for passive surveillance. Invik J et al. Journal of water and health, 2017. PubMed · DOI
In Alberta well tests from 2004 to 2012, private wells tested positive for coliform or E. coli more often than untreated public wells, and E. coli peaked in July. - Seasonality of Coliform Bacteria Detection Rates in New Jersey Domestic Wells. Atherholt TB et al. Ground water, 2017. PubMed · DOI
Ten years of New Jersey home-sale test results showed coliform bacteria were found in a higher share of wells in warm-weather months. - Microbial Contamination of Drinking Water Supplied by Private Wells after Hurricane Harvey. Pieper KJ et al. Environmental science & technology, 2021. PubMed · DOI
After Hurricane Harvey, coliform and E. coli were found more often than usual in tested wells, especially flooded ones, and disinfection did not always clear contamination. - Depth and Well Type Related to Groundwater Microbiological Contamination. Maran NH et al. International journal of environmental research and public health, 2016. PubMed · DOI
In two Brazilian cities, E. coli was found far more often in shallow dug wells than in drilled wells; contamination was linked to well depth.
Nitrate
- Nitrate contamination in private wells in rural Alabama, United States. Liu A et al. The Science of the total environment, 2005. PubMed · DOI
Over eight years of rural Alabama well samples, most nitrate levels were low, with about 1.7% above the 10 mg/L limit; well depth and nearby cropping mattered. - Nitrate in drinking water and colorectal cancer risk: A nationwide population-based cohort study. Schullehner J et al. International journal of cancer, 2018. PubMed · DOI
A Danish nationwide study of 2.7 million adults linked higher drinking-water nitrate to a modestly higher colorectal cancer risk, at levels below the current standard. - Ingested Nitrate and Nitrite and Bladder Cancer in Northern New England. Barry KH et al. Epidemiology (Cambridge, Mass.), 2020. PubMed · DOI
A New England study found higher drinking-water nitrate was associated with bladder cancer, alongside nitrate and nitrite from processed meat. - Nitrate exposure from drinking water and dietary sources among Iowa farmers using private wells. Skalaban TG et al. The Science of the total environment, 2024. PubMed · DOI
Among Iowa farmers on private wells, diet supplied most nitrate overall, but for those with well water at or above the EPA limit, water was a large share of intake.
Arsenic
- Reverse osmosis filter use and high arsenic levels in private well water. George CM et al. Archives of environmental & occupational health, 2006. PubMed · DOI
In a Nevada survey, reverse osmosis filters cut arsenic by about 79% on average, but treated water in some homes was still above 10 µg/L. Retesting treated water matters. - Lessons Learned from Arsenic Mitigation among Private Well Households. Zheng Y et al. Current environmental health reports, 2017. PubMed · DOI
A review of arsenic mitigation in US private well households: exposed homes are hard to identify, and treatment is not always kept up. - Associations between private well water and community water supply arsenic concentrations in the conterminous United States. Spaur M et al. The Science of the total environment, 2021. PubMed · DOI
Compares modeled arsenic levels in private wells and community water systems across US counties, with strong links between the two in some rural regions. - Arsenic in private well water and birth outcomes in the United States. Bulka CM et al. Environment international, 2022. PubMed · DOI
A large US study found no link between modeled private-well arsenic and gestational age, and a modest link with lower birth weight; the authors note important limitations.
PFAS (forever chemicals)
- Per- and polyfluoroalkyl substances (PFAS) in United States tapwater: Comparison of underserved private-well and public-supply exposures and associated health implications. Smalling KL et al. Environment international, 2023. PubMed · DOI
A US Geological Survey study compared PFAS in tapwater from private wells and public supplies and called for more assessment of unmonitored private wells. - Prevalence and Source Tracing of PFAS in Shallow Groundwater Used for Drinking Water in Wisconsin, USA. Silver M et al. Environmental science & technology, 2023. PubMed · DOI
In shallow Wisconsin groundwater used by private wells, higher PFAS levels were associated with developed land and signs of human waste such as septic systems. - A Statistical Approach for Identifying Private Wells Susceptible to Perfluoroalkyl Substances (PFAS) Contamination. Hu XC et al. Environmental science & technology letters, 2021. PubMed · DOI
Machine-learning models using public data on nearby industry, soils and rainfall predicted which private wells were more likely to contain PFAS. - Per- and polyfluoroalkyl ether acids in well water and blood serum from private well users residing by a fluorochemical facility near Fayetteville, North Carolina. Kotlarz N et al. Journal of exposure science & environmental epidemiology, 2024. PubMed · DOI
Near a North Carolina fluorochemical plant, blood tests were not a good measure of long-term exposure to some newer PFAS; water measurements are needed.
Lead
- Children drinking private well water have higher blood lead than those with city water. Gibson JM et al. Proceedings of the National Academy of Sciences of the United States of America, 2020. PubMed · DOI
North Carolina children in homes on private wells had 25% higher odds of elevated blood lead than children on regulated community water. - Elevated Lead in Water of Private Wells Poses Health Risks: Case Study in Macon County, North Carolina. Pieper KJ et al. Environmental science & technology, 2018. PubMed · DOI
In Macon County, NC, lead in well water came mostly from plumbing and well parts, and flushing before sampling greatly reduced how much lead was detected. - Predictors of Water Lead Levels in Drinking Water of Homes With Domestic Wells in 3 Illinois Counties. Geiger SD et al. Journal of public health management and practice : JPHMP, 2021 Nov-Dec 01. PubMed · DOI
In three Illinois counties, lead was common in private-well tap water, and older homes with more corrosive water were far more likely to have it. - Mobilization of lead and other trace elements following shock chlorination of wells. Seiler RL et al. The Science of the total environment, 2006. PubMed · DOI
Shock chlorination of wells released lead and other trace elements; drinking the water soon after treatment may mean higher lead exposure.
Uranium and radon
- Human exposure to uranium in groundwater. Orloff KG et al. Environmental research, 2004. PubMed · DOI
People who drank well water with high uranium still had elevated uranium in urine up to 10 months after they stopped drinking it. - Grand rounds: nephrotoxicity in a young child exposed to uranium from contaminated well water. Magdo HS et al. Environmental health perspectives, 2007. PubMed · DOI
A case report of a family drinking well water high in natural uranium, where the youngest child showed signs of kidney effects that improved after stopping. - Prevention measures against radiation exposure to radon in well waters: analysis of the present situation in Finland. Turtiainen T et al. Journal of water and health, 2010. PubMed · DOI
A review of Finnish studies on radon in well water: private wells are often not monitored, and home radon removal units are increasingly used. - Radon in private drinking water wells. Otahal P et al. Radiation protection dosimetry, 2014. PubMed · DOI
Measured radon, radium and uranium in water from more than 300 private wells in the Czech Republic, where public-supply limits do not apply to private sources.
Well testing behavior: who tests and why
- Improving Private Well Testing Programs: Experimental Evidence from Iowa. Lade GE et al. Environmental science & technology, 2024. PubMed · DOI
An Iowa survey found few well households test as often as recommended; free nitrate test strips plus information on free testing increased testing. - Risk Communication and Factors Influencing Private Well Testing Behavior: A Systematic Scoping Review. Colley SK et al. International journal of environmental research and public health, 2019. PubMed · DOI
A scoping review found very few studies of what gets well owners to test, though the two experimental studies suggest outreach can work. - Influences on the water testing behaviors of private well owners. Imgrund K et al. Journal of water and health, 2011. PubMed · DOI
Interviews with Ontario well owners found peace of mind motivates testing, while complacency and inconvenience hold people back; information alone was a weak driver. - Arsenic in private well water part 1 of 3: Impact of the New Jersey Private Well Testing Act on household testing and mitigation behavior. Flanagan SV et al. The Science of the total environment, 2016. PubMed · DOI
New Jersey's law requiring well tests at home sale increased testing and arsenic treatment, but many owners later misremembered results or did not maintain treatment. - The Case for Universal Screening of Private Well Water Quality in the U.S. and Testing Requirements to Achieve It: Evidence from Arsenic. Zheng Y et al. Environmental health perspectives, 2017. PubMed · DOI
Argues, using arsenic evidence, for universal screening of US private wells through local testing requirements and free, easy testing.
Test your own well
Studies describe patterns across many wells. Your well can differ, so test it with a certified lab.