Drinking Water and Your Health

Drinking water in the U.S. comes from a variety of 

sources, including public water systems, private wells, 

or bottled water. 

Worldwide, nearly 2 billion people drink contaminated 

water that could be harmful to their health.1

 Though more 

of a concern in developing countries, safe drinking water 

is a U.S. public health priority.

Possible sources of drinking water contamination are: 

• Corroded water pipes that leach harmful chemicals, 

such as lead

• Hazardous waste sites and industrial discharges

• Pesticides and fertilizers from agricultural operations

• Naturally occurring hazardous chemicals, such as arsenic

• Sewage and food processing waste

Health Effects 

Examples follow of potential drinking water contaminants 

and reported health effects, which can range from subtle 

to severe depending on the chemical and total exposure.

• Arsenic – a known human carcinogen associated with 

skin, lung, bladder, kidney, and liver cancer2

• Lead – behavioral and developmental effects in children; 

and cardiovascular and kidney problems3

• Hydraulic fracturing (fracking) chemicals – 

damage to the immune4

 and reproductive systems5

• Pesticides – neurodevelopmental effects and 

Parkinson’s disease6

What is NIEHS Doing? 

As a global public health issue, drinking water studies 

are a priority for NIEHS and the interagency National 

Toxicology Program (NTP), located at the institute. 

Topics include: 

• Fluoride – NTP is evaluating potential neurobehavioral 

and endocrine effects from fluoride in drinking water. 

• Microplastics – Grant recipients at the University of 

South Carolina research potential health effects from 

exposure to microscopic plastic particles in water.

• PFAS – NTP is evaluating some of these industrial-use 

chemicals to understand their effects on metabolism, 

biological activity in cell-based systems, and health 

effects related to cancer and the immune system.

Conducting Timely Research 

Time-sensitive grants offered by NIEHS enable researchers 

to quickly start studies after natural and human-made 

disasters, or emerging environmental public health 

threats. For example, researchers have: 

• Measured exposures in Colorado Springs’ residents 

whose water was contaminated with the PFAS 

perfluorohexane sulfonate. 

• Analyzed water in North Carolina’s Cape Fear River for 

contamination by the PFAS GenX.

• Coordinated research efforts and provided scientific 

information about testing lead in drinking water for 

residents of Flint, Michigan. 

• Studied a chemical spill (4-Methylcyclohexanemethonal, 

known as MCHM) into West Virginia’s Elk River 

that showed its water was safe to drink. Potential 

contamination levels at the time would have been too 

low to cause harm.7

Protecting Public Health

Public water supplies are usually monitored by local 

government for contaminants. Federal research 

supplements public knowledge. For example:

• Researchers discovered some Mid-Ohio River Valley 

residents have higher PFAS blood levels than most 

Americans, and industrial releases to the Ohio River 

may be a major source of exposure.8

• A collaboration among NIEHS, U.S. Environmental 

Protection Agency, and U.S. Geological Survey found 

widespread tap water contamination at home and 

workplace locations in 11 states.9

PO Box 12233 • Research Triangle Park, NC 27709

Phone: 919-541-3345 • www.niehs.nih.gov

July 2020

National Institutes of Health

U.S. Department of Health and Human Services

 Printed on recycled paper
Grant recipients of the NIEHS Superfund Research 

Program study the health effects of potentially 

hazardous substances and effective ways to clean up 

those substances from waterways. For example:

• Studies by Dartmouth College scientists on the sources 

and levels of arsenic exposure in New Hampshire 

contributed to development of a new state law 

lowering the limit for arsenic in drinking water.10

• Researchers at the University of California, Berkeley, study 

drinking water quality problems. Industrial and agricultural 

activities might result in chemical contaminants in 

drinking water such as nitrate, arsenic, pesticides, and 

chromium, particularly in rural and socioeconomically 

disadvantaged communities in California.11

• People who obtain drinking water from private wells 

should have the water quality tested regularly. 

A Columbia University study found 41% of well owners 

in central Maine have never tested for arsenic.12

• In North Carolina, about 3 million people, representing 

one-third of the state’s population, drink water from 

private wells. Researchers at the University of North 

Carolina at Chapel Hill are developing a new filtration 

device for removing arsenic and other chemicals from 

well water.13

Advancing Solutions

NIEHS seeks practical, scientific solutions to protect 

community health and the environment. Small Business 

Innovation Research and Small Business Technology 

Transfer grants support commercial technology 

development to improve public health. For example:

• ANDalyze sensors can detect specific heavy metals, 

such as cadmium, copper, and uranium, in water supplies.

• NanoAffix developed a handheld device for real-time, 

onsite detection of lead in tap water.

1 Progress on Drinking Water, Sanitation, and Hygiene (WHO). https://www.who.int/mediacentre/news/releases/2017/launch-version-report-jmp-water-sanitationhygiene.pdf. (Last accessed March 23, 2020)

2 NTP. 2016. Report on Carcinogens, Fourteenth Edition.; Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service. 

ntp.niehs.nih.gov/go/roc14

3 Agency for Toxic Substances and Disease Registry. 2007. Toxicological profile for Lead. Atlanta, GA: U.S. Department of Health and Human Services, 

Public Health Service.

4 Boule LA, et al. 2018. Developmental exposure to a mixture of 23 chemicals associated with unconventional oil and gas operations alters the immune system of mice. 

Toxicol Sci; doi:10.1093/toxsci/kfy066 [Online 01 May 2018].

5 Sapouckey SA, et al. 2018. Prenatal exposure to unconventional oil and gas operation chemical mixtures altered mammary gland development in adult female mice. 

Endocrinology 159(3):1277–1289.

6 Pesticides (NIEHS). www.niehs.nih.gov/health/topics/agents/pesticides. (Last accessed March 23, 2020)

7 West Virginia Chemical Spill (NIEHS) www.niehs.nih.gov/health/materials/west_virginia_chemical_spill_508.pdf. (Last accessed March 23, 2020)

8 Herrick RL, et al. 2017. Polyfluoroalkyl substance exposure in the Mid-Ohio River Valley, 1991-2012. Environ Pollut 228:50-60.

9 Bradley PM, et al. 2018. Reconnaissance of mixed organic and inorganic chemicals in private and public supply tapwaters at selected residential and workplace sites 

in the United States. Environ Sci Technol. 52(23): 13972-13985.

10 Dartmouth SRP Center Informs Protective Limit for Arsenic in Water (NIEHS). www.niehs.nih.gov/research/supported/centers/srp/phi/archives/publicpolicy/dartmouth. 

(Last accessed March 23, 2020)

11 University of California, Berkeley, Superfund Research Program Community Engagement Core. tools.niehs.nih.gov/srp/programs/Program_detail.cfm?Project_

ID=P42ES0047055065. (Last accessed April 6, 2020)

12 Flanagan SV, et al. 2015. Influences on domestic well water testing behavior in a Central Maine area with frequent groundwater arsenic occurrence. 

Sci Total Environ 505:1274-1281.

13 Novel Filtration Devices for Arsenic Reduction (NIEHS). tools.niehs.nih.gov/srp/programs/Program_detail.cfm?Project_ID=P42ES0310075716. 

(Last accessed April 6, 2020)

For more information on the 

National Institute of Environmental Health Sciences, 

go to www.niehs.nih.gov.

National Institute of Environmental Health Sciences

Learn More About Drinking Water

U.S. Centers for Disease Control and Prevention 

Drinking Water Guide 

www.cdc.gov/healthywater/drinking

U.S. Environmental Protection Agency 

Drinking Water Requirements

www.epa.gov/dwreginfo

Treating PFAS in Drinking Water

Effective ways to remove PFAS from water include 

activated carbon treatment, ion exchange resins, and 

reverse osmosis. These technologies can be used in 

public treatment facilities, water systems in buildings, 

or homes. Read more from the EPA: epa.gov/pfas/treatingpfas-drinking-water