Water is essential for life. People depend on safe water for their health and livelihood. But contaminated water leads to millions of deaths and even more illnesses every year.1
Water pollution is any contamination of water with chemicals or other hazardous substances that are detrimental to human, animal, or plant health.
Possible sources of 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
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.2 Though more of a concern in developing countries, safe drinking water is a U.S. public health priority.
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 cancer3
- Lead – behavioral and developmental effects in children; and cardiovascular and kidney problems4
- Hydraulic fracturing (fracking) chemicals – damage to the immune5 and reproductive systems6
- Pesticides – neurodevelopmental effects and Parkinson’s disease7
Waterborne Disease From All Water Sources
Scientists at the Centers for Disease Control and Prevention (CDC) estimated the burden and direct healthcare cost of infectious waterborne disease in the U.S. When drinking, recreational, and environmental water sources were considered together, they found more than 7 million cases of 17 different waterborne illnesses occur annually. New waterborne disease challenges are emerging due to factors such as aging infrastructure, chlorine-tolerant and biofilm-related pathogens, and increased recreational water use.
Landrigan P et al. 2018. The Lancet Commission on Pollution and Health. Feb 3;391(10119):462-512 [Abstract Landrigan P et al. 2018. The Lancet Commission on Pollution and Health. Feb 3;391(10119):462-512]
Progress on Drinking Water, Sanitation, and Hygiene (WHO).Â (Last accessed March 23, 2020) [Full Text Progress on Drinking Water, Sanitation, and Hygiene (WHO).Â (Last accessed March 23, 2020)]
NTP. 2016. Report on Carcinogens, Fourteenth Edition.; Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service. [Abstract NTP. 2016. Report on Carcinogens, Fourteenth Edition.; Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service.]
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. [Full Text 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.]
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]. [Abstract 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].]
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):1277â1289. [Abstract 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):1277â1289.]
Pesticides (NIEHS). (Last accessed March 23, 2020) [Full Text Pesticides (NIEHS). (Last accessed March 23, 2020)]
What is NIEHS Doing?
NIEHS research examines potential health effects of contaminants in water and explores ways to protect the public from contact with unsafe water.
The GuLF STUDY (Gulf Long-term Follow-up Study), funded by NIEHS and the National Institutes of Health Common Fund, studies the health of people who helped with the oil spill response and clean-up, took training, signed up to work, or were sent to the Gulf of Mexico to help in some way after the Deepwater Horizon disaster. NIEHS is leading this research effort with the support of many community groups. Nearly 33,000 people joined the study, making it the largest study ever conducted on the health effects of an oil spill. The study has tracked numerous health issues reported by cleanup workers, including skin rashes, wheezing and difficulty breathing, headaches, nausea, depression and anxiety, and heart attacks. However, the most recent publication to emerge from the research suggests that some health effects associated with the spill may resolve over time.
NIEHS and the National Science Foundation jointly fund research on marine-related health issues through the Centers for Oceans and Human Health. Grantees, for example, develop techniques for more accurate and earlier detection of harmful algal blooms with the goal of preventing and reducing exposure. They also study the health effects of eating seafood containing toxins produced by harmful algal blooms. Contaminants of emerging concern, such as microplastics, are also studied.
NIEHS offers time-sensitive grants that enable researchers to launch studies quickly in response to natural disasters, industrial accidents, or policy changes that affect water quality. In addition, the National Toxicology Program, located at NIEHS, reviews available toxicology studies and conducts short- and long-term studies to help public health officials respond to threats to the safety of drinking water. For example:
- Researchers measured PFAS exposures in residents near Colorado Springs whose water was contaminated with the PFAS perfluorohexane sulfonate (PFHxS), as well as contamination of the Cape Fear River in North Carolina by the PFAS GenX.
- Scientists were able to address the concerns of residents of Flint, Michigan about their exposure to lead, giving them rapid information on how great the risk was and ways they might limit the exposure.
- NTP completed a series of studies on the toxicity of chemicals that spilled into the Elk River in West Virginia, January 2014.
NTP is evaluating individual PFAS (per- and polyfluoroalkyl substances), which is a group of widely produced industrial-use chemicals that are found in some waterways. NTP studies seek to understand the effects of certain PFAS on metabolism, biological activity in cell-based systems, and health effects related to cancer and the immune system.
The NIEHS Superfund Research Program funds grants to study the health effects of potentially hazardous substances and to investigate effective and sustainable ways to clean up those substances at hazardous waste sites, which may include waterways.
The program’s grant recipients have developed online tools to inform local communities about potential environmental health risks.
- Scientists at University of California, Berkeley launched the Drinking Water Tool, an interactive website that helps California residents identify areas where water quality may be of concern.
- SRP-funded researchers developed therapeutic sorbents that can bind to hazardous chemicals in water, potentially reducing health problems following natural disasters, chemical spills, and other emergencies. Sorbents are insoluble materials that may be used to bind and remove contaminants from water or food. In the form of enterosorbents, they can be safely consumed by people as a way to remove certain harmful substances from the gut.
NIEHS supports the NIH Disaster Research Response (DR2) Program. This program includes ready-to-go data collection tools, research protocols, and a network of trained responders. These tools assist timely gathering of environmental and toxicological data that compliments health information collected during disaster responses. Many disasters can affect water safety.
Stories from the Environmental Factor (NIEHS Newsletter)
- Water Contaminants Identified, Addressed in Marginalized Communities (October 2023)
- Stricter Drinking Water Standards for Arsenic Benefit Highly Exposed Populations (September 2023)
- Microplastics Research: Sum of Our Exposures Studied by Grantee (July 2023)
- Geospatial Analysis Shows Disproportionate Exposure to Arsenic and Uranium Across the U.S. (February 2023)
- PFAS Water Filter Developed Through NIEHS Funding (April 2022)
- Eight Substances Added to 15th Report on Carcinogens (January 2022)
- Help Guide Research on Drinking Water, From the Source to the Tap (May 2021)
- Water Contaminant NDMA Linked to Cancer Cluster in Massachusetts (May 2021)
- Nitrogen Runoff Leads to Preventable Health Outcomes, Experts Say (April 2021)
- COVID-19 Shines Light on Navajo Water Contamination (June 2020)
Printable Fact Sheets
- Reducing Exposure to Disinfection Byproducts in Drinking Water (2023) – Before drinking water reaches a home, it is treated with chlorine to kill bacteria, viruses, and germs that can cause disease. Although this disinfection step keeps people safe from waterborne illnesses, it also has the potential to create byproducts that can harm health. These compounds – called disinfection byproducts – are formed when chlorine combines with organic matter naturally present in water. NIEHS-funded researchers work with residents in eastern Kentucky who are concerned about high levels of disinfection byproducts detected in their drinking water.
- Community Science Aids Harmful Algal Blooms Research (2022) – A NIEHS-funded community science program engages charter boat captains and U.S. Coast Guard personnel to collect water samples and other data on Lake Erie. This data allows researchers to monitor, predict, and mitigate harmful algal blooms. This community science effort, the center also increases public awareness.
- Microplastic Pollution and Human Health (2020) – Microplastics present potential health risks because they can be composed of harmful chemicals, and they accumulate additional persistent organic pollutants as they float in oceans. As microplastics become increasingly prevalent in the food chain, scientists and health professionals are giving more attention to the potential health risks for people.
- Water, Sanitation, and Hygiene (WASH) Collection – In the U.S., safe piped water is responsible for improving public health. Yet billions of people globally—including some residents of high-income countries—lack access to safely managed drinking water services. This collection of research papers published in Environmental Health Perspectives is related to WASH topics.
- Medline Plus: Drinking Water – Consumer information from Medline Plus, a service of the National Library of Medicine.
- CDC: Drinking Water – Public health information from the Centers for Disease Control and Prevention.
- Ground Water and Drinking Water – Information from the U.S. Environmental Protection Agency.
- NIH Climate Change and Health Initiative – This solutions-focused research initiative aims to reduce the health consequences associated with extreme weather events and evolving climate conditions. NIH has a strong history of creating innovative tools, technologies, and data-driven solutions to address global environmental problems.
- Reducing PFAS in Drinking Water (1MB) – In the Cincinnati area, NIEHS-funded researchers discovered high levels of a specific PFAS chemical, called perfluorooctanoate (PFOA), in young girls. This research translation story shows how they worked with local water departments to implement water filtering techniques that resulted in a 40-60% reduction in PFOA levels in the girls and other residents.
- Report on Carcinogens – This congressionally mandated, science-based, public health document is prepared by NTP for the HHS Secretary. The current report lists 248 agents, substances, mixtures, and exposure circumstances that are known or reasonably anticipated to cause cancer in humans.