Contaminants Detected
EXCEED GUIDELINES
Arsenic
Potential Effect: cancer

This Utility: 1.27 ppb
Legal Limit: 10 ppb
317x
EWG's Health Guideline: 0.004 ppb
Arsenic
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 317 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Agriculture
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Bromodichloromethane
Potential Effect: cancer

This Utility: 2.25 ppb
No Legal Limit
37x
EWG's Health Guideline: 0.06 ppb
Bromodichloromethane
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.
Bromodichloromethane was found at 37 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.06 ppb for bromodichloromethane was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Chloroform
Potential Effect: cancer

This Utility: 1.69 ppb
No Legal Limit
4.2x
EWG's Health Guideline: 0.4 ppb
Chloroform
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.
Chloroform was found at 4.2 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Chromium (hexavalent)*
Potential Effect: cancer

This Utility: 0.109 ppb
No Legal Limit
5.5x
EWG's Health Guideline: 0.02 ppb
Chromium (hexavalent)
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 5.5 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Dibromoacetic acid
Potential Effect:

This Utility: 1.52 ppb
No Legal Limit
51x
EWG's Health Guideline: 0.03 ppb
Dibromoacetic acid
Dibromoacetic 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.
Dibromoacetic acid was found at 51 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.03 ppb for dibromoacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dibromochloromethane
Potential Effect: cancer

This Utility: 1.71 ppb
No Legal Limit
17x
EWG's Health Guideline: 0.1 ppb
Dibromochloromethane
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.
Dibromochloromethane was found at 17 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.1 ppb for dibromochloromethane was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dichloroacetic acid
Potential Effect: cancer

This Utility: 0.535 ppb
No Legal Limit
2.7x
EWG's Health Guideline: 0.2 ppb
Dichloroacetic acid
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.
Dichloroacetic acid was found at 2.7 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to reproduction and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA5)
Potential Effect: cancer

This Utility: 2.72 ppb
Legal Limit: 60 ppb
27x
EWG's Health Guideline: 0.1 ppb
Haloacetic acids (HAA5)
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 27 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA9)
Potential Effect: cancer

This Utility: 10.2 ppb
No Legal Limit
170x
EWG's Health Guideline: 0.06 ppb
Haloacetic acids (HAA9)
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.
Haloacetic acids (HAA9) was found at 170 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2021.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Manganese
Potential Effect: harm to the brain and nervous system

This Utility: 233.4 ppb
No Legal Limit
2.3x
EWG's Health Guideline: 100 ppb
Manganese
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.
Manganese was found at 2.3 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Ion Exchange
Nitrate
Potential Effect: cancer

This Utility: 0.774 ppm
Legal Limit: 10 ppm
5.5x
EWG's Health Guideline: 0.14 ppm
Nitrate
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 5.5 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
Health Risks
The EWG 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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppm = parts per millionPollution Sources
Agriculture
Runoff & Sprawl
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Perfluorohexane sulfonate (PFHXS)
Potential Effect:

This Utility: 1.45 ppt
Legal Limit: 10 ppt
1,449x
EWG's Health Guideline: 0.001 ppt
Perfluorohexane sulfonate (PFHXS)
Perfluorohexane sulfonate is a member of a group of perfluorinated chemicals used in many consumer products. 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.
Perfluorohexane sulfonate (PFHXS) was found at 1,449 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
Health Risks
The EWG Health Guideline of 0.001 ppt for perfluorohexane sulfonate was defined by EPA's toxicity value published in the Integrated Risk Information System's toxicological review. This health guideline harm to the developing immune system.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorononanoic acid (PFNA)
Potential Effect:

This Utility: 0.0850 ppt
Legal Limit: 10 ppt
14x
EWG's Health Guideline: 0.006 ppt
Perfluorononanoic acid (PFNA)
Perfluorononanoic acid, otherwise known as PFNA or C9, is a PFC similar in function and use to PFOA. These chemicals were used in the production of non-stick, stain repellent and chemically inert coatings. Click here to read more about perfluorinated chemicals.
Perfluorononanoic acid (PFNA) was found at 14 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
Health Risks
The EWG Health Guideline of 6 ppt for perfluorononanoic acid was defined by EPA recommended application of the toxicity value for PFDA published in the Integrated Risk Information System’s toxicological review . This health guideline harm to the immune system and harm to fetal growth and child development.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorooctane sulfonate (PFOS)
Potential Effect:

This Utility: 4.08 ppt
Proposed Legal Limit: 4 ppt
14x
EWG's Health Guideline: 0.3 ppt
Perfluorooctane sulfonate (PFOS)
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.
Perfluorooctane sulfonate (PFOS) was found at 14 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Proposed Legal Limit
National Average
State Average
Health Risks
The EWG Health Guideline of 0.3 ppt for PFOS was defined by EPA's final toxicity value from the Office of Water’s Final Human Health Toxicity Assessment. This health guideline protects againat cardiovascular harm and harm to fetal growth.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorooctanoic acid (PFOA)
Potential Effect: cancer

This Utility: 5.57 ppt
Proposed Legal Limit: 4 ppt
62x
EWG's Health Guideline: 0.09 ppt
Perfluorooctanoic acid (PFOA)
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 62 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Proposed Legal Limit
National Average
State Average
Health Risks
The EWG Health Guideline of 0.09 ppt for PFOA was was defined by EPA's final toxicity value from the Office of Water’s Final Human Health Toxicity Assessment. This health guideline protects againat cardiovascular harm and harm to fetal growth.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Radium, combined (-226 and -228)
Potential Effect: cancer

This Utility: 0.34 pCi/L
Legal Limit: 5 pCi/L
6.8x
EWG's Health Guideline: 0.05 pCi/L
Radium, combined (-226 and -228)
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 and -228) was found at 6.8 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2023.
pCi/L = picocuries per literPollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Total trihalomethanes (TTHMs)
Potential Effect: cancer

This Utility: 21.7 ppb
Legal Limit: 80 ppb
144x
EWG's Health Guideline: 0.15 ppb
Total trihalomethanes (TTHMs)
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.
Total trihalomethanes (TTHMs) was found at 144 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Trichloroacetic acid
Potential Effect: cancer

This Utility: 0.660 ppb
No Legal Limit
6.6x
EWG's Health Guideline: 0.1 ppb
Trichloroacetic acid
Trichloroacetic 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.
Trichloroacetic acid was found at 6.6 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.1 ppb for trichloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to reproduction and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Includes chemicals detected in 2021-2023 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority; radiological contaminants detected between 2018 and 2023.
*This water utility buys or otherwise receives some or all of its finished water from Worcester Department of Public Works. Tap water results marked with an * are from the supplying utility.
† 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.
OTHER DETECTED
1,1-Dichloroethylene

This Utility: 0.0540 ppb
Legal Limit: 7 ppb
No EWG Health Guideline
1,1-Dichloroethylene
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
EWG Health Guideline
Not yet determined
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Industry
Filtering Options
Activated Carbon
Reverse Osmosis
Aluminum

This Utility: 56.1 ppb
No Legal Limit
EWG's Health Guideline: 600 ppb
Aluminum
Aluminum is a metal released from metal refineries and mining operations. Too much aluminum exposure can impair children's brain development.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 600 ppb for aluminum 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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Barium

This Utility: 65.7 ppb
Legal Limit: 2,000 ppb
EWG's Health Guideline: 700 ppb
Barium
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
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Bromoform

This Utility: 0.547 ppb
No Legal Limit
EWG's Health Guideline: 0.5 ppb
Bromoform
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
Health Risks
The EWG Health Guideline of 0.5 ppb for bromoform is based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer, harm to reproduction and child development, and change to fetal growth and development .
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Chloromethane

This Utility: 0.0193 ppb
No Legal Limit
EWG's Health Guideline: 2.69 ppb
Chloromethane
Chloromethane is an industrial solvent, aerosol propellant and a refrigerant. It also forms as a byproduct of water disinfection. The EPA classifies chloromethane as possibly carcinogenic to humans.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 2.69 ppb for chloromethane was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against cancer.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2023.
ppb = parts per billionPollution Sources
Industry
Treatment Byproducts
Naturally Occurring
Filtering Options
Activated Carbon
Reverse Osmosis
Fluoride

This Utility: 0.0286 ppm
Legal Limit: 4 ppm
No EWG Health Guideline
Fluoride
Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems to prevent cavities and support oral health in people.
In 2015, the Department of Health and Human Services updated its recommendation of an optimal level of 0.7 parts per million, or ppm, added to drinking water based on the health benefits of tooth decay prevention. Studies have shown that fluoride added to community water systems at this level reduces dental cavities, especially in children.
And studies have conclusively shown that fluoride in toothpaste and mouthwash can also provide these benefits.
How your levels compare
This Utility
Legal Limit
National Average
State Average
EWG Health Guideline
Not yet determined
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppm = parts per millionPollution Sources
Industry
Treatment Byproducts
Naturally Occurring
Filtering Options
Reverse Osmosis
Monochloroacetic acid*

This Utility: 1.33 ppb
No Legal Limit
EWG's Health Guideline: 53 ppb
Monochloroacetic acid
Monochloroacetic 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
Health Risks
The EWG Health Guideline of 53 ppb for monochloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk.a public health goal. This health guideline protects against change to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
MTBE

This Utility: 0.0104 ppb
No Legal Limit
EWG's Health Guideline: 13 ppb
MTBE
MTBE was used as gasoline oxygenation additive to boost the octane number. In 2005, MTBE was replaced by ethanol as a gasoline additive. MTBE causes cancers in rats.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 13 ppb for MTBE 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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorobutane sulfonate (PFBS)

This Utility: 2.20 ppt
No Legal Limit
EWG's Health Guideline: 2,000 ppt
Perfluorobutane sulfonate (PFBS)
Perfluorobutane sulfonate (PFBS) 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
National Average
State Average
Health Risks
The EWG Health Guideline of 2,000 ppt for perfluorobutane sulfonate was defined by EPA’s Human Health toxicity value. This health guideline hormone disruption and harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluoroheptanoic acid (PFHPA)

This Utility: 1.65 ppt
No Legal Limit
EWG's Health Guideline: 1,000 ppt
Perfluoroheptanoic acid (PFHPA)
Perfluoroheptanoic acid is a member of a group of perfluorinated chemicals used in many consumer products. 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
National Average
State Average
Health Risks
The EWG Health Guideline of 1,000 ppt for perfluoroheptanoic acid was defined by EPA's recommended application of the toxicity value for PFHxA published in the Integrated Risk Information System’s toxicological review. This health guideline harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorohexanoic Acid (PFHxA)

This Utility: 1.55 ppt
No Legal Limit
EWG's Health Guideline: 1,000 ppt
Perfluorohexanoic Acid (PFHxA)
Perfluorohexanoic acid is a member of a group of perfluorinated chemicals used in many consumer products. 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
National Average
State Average
Health Risks
The EWG Health Guideline of 1,000 ppt for perfluorohexanoic acid was defined by EPA's toxicity value published in the Integrated Risk Information System's toxicological review. This health guideline protects against harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluoropentanoic Acid (PFPeA)*

This Utility: 0.800 ppt
No Legal Limit
EWG's Health Guideline: 1,000 ppt
Perfluoropentanoic Acid (PFPeA)
Perfluoropentanoic Acid (PFPeA) 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
National Average
State Average
Health Risks
The EWG Health Guideline of 1,000 ppt for PFPeA was defined by EPA's recommended application of the toxicity value for PFHxA published in the Integrated Risk Information System’s toxicological review. This health guideline protects against harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorotetradecanoic acid (PFTA)

This Utility: 0.00700 ppt
No Legal Limit
EWG's Health Guideline: 0.006 ppt
Perfluorotetradecanoic acid (PFTA)
Perfluorotetradecanoic acid (PFTA) is a member of a group of perfluorinated chemicals used in many consumer products. PFTA 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
National Average
State Average
Health Risks
The EWG Health Guideline of 0.006 ppt for PFTA was based on the EPA's recommended application of the toxicity value for PFDA published in the Integrated Risk Information System’s toxicological review. This health guideline protects against harm to the immune system and harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Strontium*

This Utility: 0.0438 ppb
No Legal Limit
EWG's Health Guideline: 1,500 ppb
Strontium
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
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Includes chemicals detected in 2021-2023 for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authority.
Other Contaminants Tested
✕Chemicals tested for but not detected:
1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloroethane, 1,1-Dichloropropene, 1,2,3-Trichlorobenzene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2,4-Trimethylbenzene, 1,2-Dibromo-3-chloropropane (DBCP), 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichloropropane, 1,3-Dichloropropene, 1-butanol, 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic aci, 2,2-Dichloropropane, 2,4,5-TP (Silvex), 2-methoxyethanol, 2-propen-1-ol, 3-Hydroxycarbofuran, 4,8-dioxa-3H-perfluorononanoic acid (ADONA), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (, Acetone, Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Alpha-hexachlorocyclohexane, Antimony, Asbestos, Atrazine, Benzene, Benzo[a]pyrene, Beryllium, Bromobenzene, Bromochloromethane, Bromomethane, Butachlor, Butylated hydroxyanisole, Cadmium, Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chloroethane, Chlorpyriphos, Chromium (total), cis-1,2-Dichloroethylene, Cyanide, Dalapon, Di(2-ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Dibromomethane, Dicamba, Dichlorodifluoromethane, Dichloromethane (methylene chloride), Dieldrin, Dimethipin, Dinoseb, Endrin, Ethoprop, Ethylbenzene, Ethylene dibromide, Germanium, Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Hexafluoropropylene oxide dimer acid (HFPO-DA), Isopropylbenzene, Lindane, m-Dichlorobenzene, Mercury (inorganic), Methomyl, Methoxychlor, Metolachlor, Metribuzin, Monobromoacetic acid, Monochlorobenzene (chlorobenzene), n-Butylbenzene, N-ethyl perfluorooctane sulfonamido acetic acid (N, N-methyl perfluorooctanesulfonamidoacetic acid, n-Propylbenzene, Naphthalene, Nitrite, o-Chlorotoluene, o-Dichlorobenzene, o-toluidine, Oxamyl (Vydate), Oxyflurofen, p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, Pentachlorophenol, Perchlorate, Perfluorodecanoic acid (PFDA), Perfluorododecanoic acid (PFDoA), Perfluorotridecanoic acid (PFTrDA), Perfluoroundecanoic acid (PFUnA), Permethrin, Picloram, Polychlorinated biphenyls (PCBs), Profenofos, Propachlor, Quinoline, sec-Butylbenzene, Selenium, Silver, Simazine, Styrene, Tebuconazole, tert-Butylbenzene, Tetrachloroethylene (perchloroethylene), Thallium, Toluene, Toxaphene, trans-1,2-Dichloroethylene, Tribufos, Trichloroethylene, Trichlorofluoromethane, Vinyl chloride, Xylenes (total)
Find A Filter
Utility:
Auburn Water DistrictCarbon Filters
FILTERS 13 contaminants exceeding guidelines (+10 others)
Can reduce the levels of many common contaminants.
pros
- Lower upfront cost
- Reduced maintenance
cons
- Does not remove all contaminants
Reverse Osmosis
FILTERS 17 contaminants exceeding guidelines (+14 others)
Can reduce the levels of many common contaminants.
pros
- Most effective
cons
- Higher upfront cost
- Requires more maintenance
- Wastes water
Other Considerations
Ion Exchange
Pros: Softens hard water, Reduces some contaminants
Cons: Doesn’t remove all contaminants
Whole-House Filters
Pros: Useful for reducing radiologicals and TCE
Cons: Expensive to install and maintain, Risk of bacterial contamination
Distillation
Pros: Removes heavy metals and harmful microbes
Cons: Does not reduce most contaminants
Explore filter options for each contaminant. See which technologies are effective at reducing specific contaminants to help you make an informed decision on the best water treatment solution for your needs.
CONTAMINANTS ABOVE HEALTH GUIDELINES | activated carbon | reverse osmosis | ion exchange |
Arsenic | |||
Bromodichloromethane | |||
Chloroform | |||
Chromium (hexavalent) | |||
Dibromoacetic acid | |||
Dibromochloromethane | |||
Dichloroacetic acid | |||
Haloacetic acids (HAA5) | |||
Haloacetic acids (HAA9) | |||
Manganese | |||
Nitrate | |||
Perfluorohexane sulfonate (PFHXS) | |||
Perfluorononanoic acid (PFNA) | |||
Perfluorooctane sulfonate (PFOS) | |||
Perfluorooctanoic acid (PFOA) | |||
Radium, combined (-226 & -228) | |||
Total trihalomethanes (TTHMs) | |||
Trichloroacetic acid | |||
OTHER CONTAMINANTS DETECTED | activated carbon | reverse osmosis | ion exchange |
1,1-Dichloroethylene | |||
Aluminum | |||
Barium | |||
Bromoform | |||
Chloromethane | |||
Fluoride | |||
Monochloroacetic acid | |||
MTBE | |||
Perfluorobutane sulfonate (PFBS) | |||
Perfluoroheptanoic acid (PFHPA) | |||
Perfluorohexanoic Acid (PFHxA) | |||
Perfluoropentanoic acid (PFPeA) | |||
Perfluorotetradecanoic acid (PFTA) | |||
Strontium |