Town of Hempstead Water Department
EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the New York Department of Health - Bureau of Public Water Supply Protection, as well as information from the U.S. EPA Enforcement and Compliance History database (ECHO). For the latest quarter assessed by the U.S. EPA (January 2021 - March 2021), tap water provided by this water utility was in compliance with federal health-based drinking water standards.
Utility Details
- Hempstead, New York
- Serves: 110,000
- Data available: 2014-2019
- Source: Groundwater
Contaminants Detected
9
EXCEED
EWG HEALTH
GUIDELINES
45 Total Contaminants
- Legal does not necessarily equal safe. Getting a passing grade from the federal government does not mean the water meets the latest health guidelines.
- Legal limits for contaminants in tap water have not been updated in almost 20 years.
- The best way to ensure clean tap water is to keep pollution out of source water in the first place.
Legal ≠ Safe
EWG Health Guidelines fill the gap in outdated government standards.
The federal government’s legal limits are not health-protective. The EPA has not set a new tap water standard in almost 20 years, and some standards are more than 40 years old.
Contaminants Detected
1,4-Dioxane
Potential Effect: cancer2.4x EWG'S HEALTH GUIDELINE1,4-Dioxane
more aboutthis contaminant
1,4-Dioxane is a solvent classified by the EPA as a likely human carcinogen. It contaminates groundwater in many states due to industrial wastewater discharges, plastic manufacturing runoff and landfill runoff.
1,4-Dioxane was found at 2.4 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.35 ppb for 1,4-dioxane was defined by the Environmental Protection Agency as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Industry

Runoff & Sprawl
Filtering Options

Reverse Osmosis
Arsenic
Potential Effect: cancer13x EWG'S HEALTH GUIDELINEArsenic
more aboutthis contaminant
Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.
Arsenic was found at 13 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.004 ppb for arsenic was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Agriculture

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Chromium (hexavalent)
Potential Effect: cancer14x EWG'S HEALTH GUIDELINEChromium (hexavalent)
more aboutthis contaminant
Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).
Chromium (hexavalent) was found at 14 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Haloacetic acids (HAA5)†
Potential Effect: cancer2.6x EWG'S HEALTH GUIDELINEHaloacetic acids (HAA5)
more aboutthis contaminant
Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of five haloacetic acids regulated by federal standards includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid.
Haloacetic acids (HAA5) was found at 2.6 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for the group of five haloacetic acids, or HAA5, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level. This health guideline protects against cancer.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Nitrate
Potential Effect: cancer19x EWG'S HEALTH GUIDELINENitrate
more aboutthis contaminant
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.
Nitrate was found at 19 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Health Risks
The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.
Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Nitrate and nitrite
Potential Effect: cancer20x EWG'S HEALTH GUIDELINENitrate and nitrite
more aboutthis contaminant
Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.
Nitrate and nitrite was found at 20 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Health Risks
The health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Perchlorate
Potential Effect: harm to the thyroid2.1x EWG'S HEALTH GUIDELINEPerchlorate
more aboutthis contaminant
Perchlorate, a component of rocket fuel, occurs both naturally and as a synthetic chemical. Ingested perchlorate interferes with thyroid function. Exposure to perchlorate during pregnancy and childhood can impair cognitive development.
Perchlorate was found at 2.1 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1 ppb for perchlorate was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against hormone disruption.
Pollution Sources

Agriculture

Industry
Filtering Options

Reverse Osmosis

Ion Exchange
Perfluorooctanoic acid (PFOA)
Potential Effect: cancer372x EWG'S HEALTH GUIDELINEPerfluorooctanoic acid (PFOA)
more aboutthis contaminant
Perfluorooctanoic acid (PFOA) is a member of a group of perfluorinated chemicals used in many consumer products. PFOA and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.
Perfluorooctanoic acid (PFOA) was found at 372 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Proposed Legal Limit
National Average
State Average
ppt = parts per trillion
Health Risks
The EWG Health Guideline of 0.007 ppt for PFOA was proposed by California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.Pollution Sources

Industry

Runoff & Sprawl
Filtering Options

Activated Carbon

Reverse Osmosis
Radium, combined (-226 & -228)
Potential Effect: cancer10x EWG'S HEALTH GUIDELINERadium, combined (-226 & -228)
more aboutthis contaminant
Radium is a radioactive element that causes bone cancer and other cancers. It can occur naturally in groundwater, and oil and gas extraction activities such as hydraulic fracturing can elevate concentrations.
Radium, combined (-226 & -228) was found at 10 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
pCi/L = picocuries per liter
Health Risks
EWG applied the health guideline of 0.05 pCi/L, defined by the California Office of Environmental Health Hazard Assessment as a public health goal for radium-226, to radium-226 and radium-228 combined. This health guideline protects against cancer.Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Includes chemicals detected in 2017-2019 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority; radiological contaminants detected between 2014 and 2019.
† HAA5 is a contaminant group that includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid. HAA9 is a contaminant group that includes the chemicals in HAA5 and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid and tribromoacetic acid. TTHM is a contaminant group that includes bromodichloromethane, bromoform, chloroform and dibromochloromethane.
1,1,1-Trichloroethane
more aboutthis contaminant
1,1,1-Trichloroethane is a solvent and a degreasing agent used for manufacturing metal products and as ingredient in cleaners and aerosols. Exposure to 1,1,1-trichloroethane can harm the nervous system, liver and circulatory system.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
1,1-Dichloroethane
more aboutthis contaminant
1,1-Dichloroethane is used in industrial chemical synthesis; in plastics, paint, varnish and finish removers; and as a pesticide. It can cause cancer.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 3 ppb for 1,1-dichloroethane was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
1,1-Dichloroethylene
more aboutthis contaminant
1,1-Dichloroethylene is used for plastics production. It damages DNA and causes cancer in laboratory animal studies.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
1,2,3-Trichloropropane
more aboutthis contaminant
1,2,3-Trichloropropane is a potent carcinogen that contaminates drinking water in agricultural regions where it was historically used as soil fumigant. Click here to read more about carcinogenic VOCs.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.0007 ppb for 1,2,3-trichloropropane was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Antimony
more aboutthis contaminant
Antimony is a naturally occurring metal that enters tap water from plumbing fittings and also from industrial uses, such as production of metal alloys, batteries and plastics. Antimony causes organ damage and shortens lifespans in studies of laboratory animals.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1 ppb for antimony was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against change to the stomach and intestines.
Pollution Sources

Industry

Runoff & Sprawl

Naturally Occurring
Filtering Options

Reverse Osmosis
Barium is a mineral present in rocks, soil and water. High concentrations of barium in drinking water increase the risk of cardiovascular disease and hypertension.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 700 ppb for barium was defined by EWG as benchmark that protects against harm to the kidneys and the cardiovascular system.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Beryllium
more aboutthis contaminant
Beryllium is a toxic metal that is both naturally occurring and released into the environment from industrial pollution and incineration. Beryllium can damage lungs, bones and the digestive system.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1 ppb for beryllium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to the stomach and intestines.
Pollution Sources

Industry
Filtering Options

Reverse Osmosis

Ion Exchange
Bromochloromethane
more aboutthis contaminant
Bromochloromethane is a tap water disinfection byproduct; it is also used as an intermediate in chemical manufacturing and as a fire extinguishing agent. Disinfection byproducts in drinking water increase the risk of cancer.
How your levels compare
This Utility
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Bromodichloromethane
more aboutthis contaminant
Bromodichloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromodichloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.06 ppb for bromodichloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Bromoform
more aboutthis contaminant
Bromoform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromoform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.5 ppb for bromoform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Bromomethane
more aboutthis contaminant
Bromomethane, or methyl bromide, is a pesticide fumigant that was banned because it depletes the ozone layer.
How your levels compare
This Utility
National Average
State Average
ppb = parts per billion
Pollution Sources

Agriculture
Filtering Options

Activated Carbon

Reverse Osmosis
Carbon tetrachloride
more aboutthis contaminant
Carbon tetrachloride, a volatile carcinogenic solvent, has been used in industrial chemical production and as a dry cleaning ingredient.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for carbon tetrachloride was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Chlorate
more aboutthis contaminant
Chlorate forms in drinking water as a byproduct of disinfection. Chlorate impairs thyroid function, making chlorate exposure most harmful during pregnancy and childhood.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 210 ppb for chlorate was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against hormone disruption.
Pollution Sources

Agriculture

Industry

Treatment Byproducts
Chlorodifluoromethane
more aboutthis contaminant
Chlorodifluoromethane (Freon 22) is a refrigerant, solvent and aerosol propellant banned in 2000 under the Montreal Protocol because of its ozone-depleting properties. Freons can cause heart, nervous system and liver damage.
How your levels compare
This Utility
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry
Chloroform
more aboutthis contaminant
Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Chromium (total)
more aboutthis contaminant
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
cis-1,2-Dichloroethylene
more aboutthis contaminant
1,2-Dichloroethylene, a neurotoxic solvent, exists in two different forms: trans-1,2-dichloroethylene and cis-1,2-dichloroethylene. A mixture of the two forms is used to manufacture other solvents and chemical products.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Cobalt is a metal found throughout the environment; people may be exposed to cobalt in air, food and drinking water.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 70 ppb for cobalt was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against change in blood chemistry.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Dibromochloromethane
more aboutthis contaminant
Dibromochloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Dibromochloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for dibromochloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Dibromomethane
more aboutthis contaminant
Dibromomethane is an industrial chemical and is also formed when disinfectants like chlorine are added to drinking water.
How your levels compare
This Utility
National Average
State Average
ppb = parts per billion
Pollution Sources

Industry

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Dichloroacetic acid
more aboutthis contaminant
Dichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Haloacetic acids (HAA9)
more aboutthis contaminant
Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of nine haloacetic acids includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid, which are regulated as a group by the federal government (HAA5); and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid, and tribromoacetic acid.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.06 ppb for the group of nine haloacetic acids, or HAA9, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level as . This health guideline protects against cancer.
Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Manganese
more aboutthis contaminant
Manganese is a naturally occurring element that is common in food and drinking water. Excessive manganese exposures may impair children's attention, memory and intellectual capacity. Click here to read more about manganese.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 100 ppb for manganese was defined by the state of Minnesota as a health risk limit, the concentration of a contaminant that can be consumed with little or no risk to health. This health guideline protects against harm to the brain and nervous system.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Ion Exchange
Perfluorooctane sulfonate (PFOS)
Perfluorooctane sulfonate (PFOS)
more aboutthis contaminant
Perfluorooctane sulfonate (PFOS) is a member of a group of perfluorinated chemicals used in many consumer products. PFOS and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.
How your levels compare
EWG Health Guideline
This Utility
Proposed Legal Limit
National Average
State Average
ppt = parts per trillion
Health Risks
The EWG Health Guideline of 1 ppt for PFOS was defined by EWG based on studies by Phillipe Grandjean of Harvard University and many other independent researchers who found reduced effectiveness of vaccines and adverse impacts on mammary gland development from exposure to PFOA and PFOS, the two PFAS most widely detected in drinking water. This health guideline applies to the entire class of PFAS detected in water.
Pollution Sources

Industry

Runoff & Sprawl
Filtering Options

Activated Carbon

Reverse Osmosis
Selenium
more aboutthis contaminant
Selenium is an essential element in diets. But too much selenium can decrease thyroid hormone production and cause hair loss, skin lesions and brittle fingernails.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 30 ppb for selenium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against hair loss and nail damage.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis
Strontium
more aboutthis contaminant
Strontium is a metal that accumulates in the bones. Radioactive strontium-90 can cause bone cancer and leukemia, and any form of strontium at high doses can harm bone health.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1,500 ppb for strontium was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against harm to bones.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Styrene
more aboutthis contaminant
Styrene is a volatile cancer-causing chemical used for manufacturing Styrofoam (polystyrene) and other plastics. Releases from industrial production sites and hazardous waste landfills cause styrene contamination in drinking water.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.5 ppb for styrene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Tetrachloroethylene (perchloroethylene)
Tetrachloroethylene (perchloroethylene)
more aboutthis contaminant
Dry cleaning chemical tetrachloroethylene, or perc, can cause cancer. It pollutes soil and groundwater due to emissions from dry cleaning facilities, and automotive, metalworking and other industries.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.06 ppb for tetrachloroethylene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources

Industry

Runoff & Sprawl
Filtering Options

Activated Carbon

Reverse Osmosis
Thallium
more aboutthis contaminant
Thalium is a naturally occurring metal released into the environment from metal smelting and coal burning. Exposure to too much thalium can cause hair loss, liver damage, reduced sperm motility and nervous system impairment.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for thallium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.
Pollution Sources

Industry
Filtering Options

Reverse Osmosis

Ion Exchange
Toluene
more aboutthis contaminant
Toluene is a volatile solvent that harms the nervous and immune systems, damages the liver and may increase the risk of miscarriage and birth defects.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 150 ppb for toluene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Total trihalomethanes (TTHMs)†
Total trihalomethanes (TTHMs)
more aboutthis contaminant
Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.Pollution Sources

Treatment Byproducts
Filtering Options

Activated Carbon

Reverse Osmosis
Trichloroethylene
more aboutthis contaminant
Trichloroethylene, an industrial solvent and common groundwater pollutant, damages the immune system, harms the developing fetus and causes cancer.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.4 ppb for trichloroethylene was defined by the state of Minnesota as health risk limit, the concentration of a contaminant that can be consumed with little or no risk to health. This health guideline protects against harm to the developing fetus and damage to the immune system.
Pollution Sources

Industry
Filtering Options

Activated Carbon

Reverse Osmosis
Trichlorotrifluoroethane
more aboutthis contaminant
Trichlorotrifluoroethane (Freon 113) is a refrigerant, solvent and aerosol propellant banned in 2000 under the Montreal Protocol because of its ozone-depleting properties. Freons can cause heart, nervous system and liver damage.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 4,000 ppb for trichlorotrifluoroethane was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.
Pollution Sources

Industry

Runoff & Sprawl
Uranium
more aboutthis contaminant
Uranium is a known human carcinogen. The federal legal limit for uranium is set at 30 micrograms per liter (corresponding to parts per billion), but utilities can also report uranium in picocuries per liter (pCi/L), which is a measure of radioactivity in water. EWG translated all uranium results to pCi/L using a conversion factor developed by the EPA. With this conversion approach, the limit of 30 ppb corresponds to 20 pCi/L. Drinking water with this much uranium would cause more than 4.6 cancer cases in a population of 100,000. California set a public health goal for uranium of 0.43 pCi/L.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
pCi/L = picocuries per liter
Health Risks
The EWG Health Guideline of 0.43 pCi/L for uranium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. Three most common uranium isotopes are U-234, U-235 and U-238. All isotopes of uranium are radioactive, and the total radioactivity depends on the ratio of isotopes. This health guideline protects against cancer.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Reverse Osmosis

Ion Exchange
Vanadium
more aboutthis contaminant
Vanadium is a metal used in steels and other alloys. People are commonly exposed to vanadium in water and food. Excessive exposure can be toxic during pregnancy and childhood.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 21 ppb for vanadium was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against change in blood chemistry.
Pollution Sources

Industry

Naturally Occurring
Filtering Options

Ion Exchange
Xylenes (total)
more aboutthis contaminant
Xylenes are solvents used in industrial and consumer products, such as cleaning agents and paint thinners. Xylenes cause nervous system damage and may harm developing fetuses.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1,800 ppb for xylenes was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to the brain and nervous system.
Pollution Sources

Industry

Runoff & Sprawl
Filtering Options

Activated Carbon

Reverse Osmosis
Includes chemicals detected in 2017-2019 for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authority; ; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 4) program in 2017 to 2020 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authori.
Other Contaminants Tested
✕Town of Hempstead Water Department compliance with legally mandated federal standards:
- From April 2019 to March 2021, Town of Hempstead Water Department complied with health-based drinking water standards.
Information in this section on Town of Hempstead Water Department comes from the U.S. EPA Enforcement and Compliance History Online database (ECHO).
LEARN MORE ABOUT THIS UTILITYWater Filters That Can Reduce Contaminant Levels
Contaminant | Activated Carbon | Reverse Osmosis | Ion Exchange |
CONTAMINANTS ABOVE HEALTH GUIDELINES | |||
1,4-Dioxane | ✔ | ||
Arsenic | ✔ | ✔ | |
Chromium (hexavalent) | ✔ | ✔ | |
Haloacetic acids (HAA5) | ✔ | ✔ | |
Nitrate | ✔ | ✔ | |
Nitrate & nitrite | ✔ | ✔ | |
Perchlorate | ✔ | ✔ | |
Perfluorooctanoic acid (PFOA) | ✔ | ✔ | |
Radium, combined (-226 & -228) | ✔ | ✔ | |
OTHER CONTAMINANTS DETECTED | |||
1,1,1-Trichloroethane | ✔ | ✔ | |
1,1-Dichloroethane | ✔ | ✔ | |
1,1-Dichloroethylene | ✔ | ✔ | |
1,2,3-Trichloropropane | ✔ | ✔ | |
Antimony | ✔ | ||
Barium | ✔ | ✔ | |
Beryllium | ✔ | ✔ | |
Bromochloromethane | ✔ | ✔ | |
Bromodichloromethane | ✔ | ✔ | |
Bromoform | ✔ | ✔ | |
Bromomethane | ✔ | ✔ | |
Carbon tetrachloride | ✔ | ✔ | |
Chlorate | |||
Chlorodifluoromethane | |||
Chloroform | ✔ | ✔ | |
Chromium (total) | ✔ | ✔ | |
cis-1,2-Dichloroethylene | ✔ | ✔ | |
Cobalt | ✔ | ✔ | |
Dibromochloromethane | ✔ | ✔ | |
Dibromomethane | ✔ | ✔ | |
Dichloroacetic acid | ✔ | ✔ | |
Haloacetic acids (HAA9) | ✔ | ✔ | |
Manganese | ✔ | ||
Perfluorooctane sulfonate (PFOS) | ✔ | ✔ | |
Selenium | ✔ | ||
Strontium | ✔ | ✔ | |
Styrene | ✔ | ✔ | |
Tetrachloroethylene (perchloroethylene) | ✔ | ✔ | |
Thallium | ✔ | ✔ | |
Toluene | ✔ | ✔ | |
Total trihalomethanes (TTHMs) | ✔ | ✔ | |
Trichloroethylene | ✔ | ✔ | |
Trichlorotrifluoroethane | |||
Uranium, combined (pCi/L) | ✔ | ✔ | |
Vanadium | ✔ | ||
Xylenes (total) | ✔ | ✔ |
Take Action
Contact Your Local Official
One of the best ways to push for cleaner water is to hold accountable the elected officials who have a say in water quality – from city hall and the state legislature to Congress all the way to the Oval Office – by asking questions and demanding answers.
LEARN MOREFilter Out Contaminants
Check out our recommendations for filters to protect your water against the detected contaminants.
EWG’S WATER FILTER GUIDE