Know Your Environment. Protect Your Health.

UTILITY

Medfield Estates S/d

location

Cary, North Carolina

serves

779

source

Groundwater

data

2018-2023

Overview

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the North Carolina Department of Environment and Natural Resources, 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 (April 2024 - June 2024), tap water provided by this water utility was in compliance with federal health-based drinking water standards.

Contaminants Detected

Bromodichloromethane

Potential Effect: cancer

This Utility: 0.967 ppb

16x

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 16 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

0.967 ppb

National Average

5.89 ppb

State Average

7.17 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Chloroform

Potential Effect: cancer

This Utility: 1.000 ppb

2.5x

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 2.5 times above EWG's Health Guideline.

EWG Health Guideline

0.4 ppb or less

This Utility

1 ppb

National Average

16.2 ppb

State Average

24.2 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Dibromochloromethane

Potential Effect: cancer

This Utility: 0.967 ppb

9.7x

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 9.7 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

0.967 ppb

National Average

3.55 ppb

State Average

2.88 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Dichloroacetic acid

Potential Effect: cancer

This Utility: 1.23 ppb

6.2x

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 6.2 times above EWG's Health Guideline.

EWG Health Guideline

0.2 ppb or less

This Utility

1.23 ppb

National Average

8 ppb

State Average

11.9 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Haloacetic acids (HAA5)

Potential Effect: cancer

This Utility: 1.23 ppb

12x

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 12 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

1.23 ppb

Legal Limit

60 ppb

National Average

19.8 ppb

State Average

21.8 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Nitrate

Potential Effect: cancer

This Utility: 2.09 ppm

15x

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 15 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

2.09 ppm

Legal Limit

10 ppm

National Average

0.824 ppm

State Average

0.0862 ppm

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 million

Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Nitrate and nitrite

Potential Effect: cancer

This Utility: 2.09 ppm

15x

EWG's Health Guideline: 0.14 ppm

Nitrate and nitrite

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 15 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

2.09 ppm

Legal Limit

10 ppm

National Average

0.78 ppm

State Average

0.104 ppm

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 million

Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Radium, combined (-226 and -228)

Potential Effect: cancer

This Utility: 0.40 pCi/L

7.9x

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 7.9 times above EWG's Health Guideline.

EWG Health Guideline

0.05 pCi/L or less

This Utility

0.4 pCi/L

Legal Limit

5 pCi/L

National Average

0.33 pCi/L

State Average

0.17 pCi/L

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 liter

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Total trihalomethanes (TTHMs)

Potential Effect: cancer

This Utility: 2.93 ppb

20x

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 20 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

2.93 ppb

Legal Limit

80 ppb

National Average

29.1 ppb

State Average

35.7 ppb

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 billion

Pollution 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.

† 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.

Chlordane

This Utility: 0.0333 ppb

EWG's Health Guideline: 0.03 ppb

Chlordane

The cancer-causing pesticide chlordane was banned in 1988. Chlordane is persistent and accumulates in the body. It is still found in the environment and in the bodies of adults and newborn babies.

How your levels compare

EWG Health Guideline

0.03 ppb or less

This Utility

0.0333 ppb

Legal Limit

2 ppb

National Average

0.00016 ppb

State Average

0.000149 ppb

Health Risks

The EWG Health Guideline of 0.03 ppb for chlordane 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 billion

Pollution Sources

Agriculture

Runoff & Sprawl

Filtering Options

Activated Carbon

Reverse Osmosis

Fluoride

This Utility: 0.0200 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

0.02 ppm

Legal Limit

4 ppm

National Average

0.49 ppm

State Average

0.51 ppm

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 million

Pollution Sources

Industry

Treatment Byproducts

Naturally Occurring

Filtering Options

Reverse Osmosis

Heptachlor epoxide

This Utility: 0.00578 ppb

EWG's Health Guideline: 0.006 ppb

Heptachlor epoxide

Heptachlor epoxide is a breakdown product of heptachlor, a highly toxic and carcinogenic pesticide banned in the U.S. since the 1980s.

How your levels compare

EWG Health Guideline

0.006 ppb or less

This Utility

0.00578 ppb

Legal Limit

0.2 ppb

National Average

0.000026 ppb

State Average

0.000033 ppb

Health Risks

The EWG Health Guideline of 0.006 ppb for heptachlor epoxide 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 billion

Pollution Sources

Agriculture

Filtering Options

Activated Carbon

Reverse Osmosis

Manganese

This Utility: 28.9 ppb

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.

How your levels compare

EWG Health Guideline

100 ppb or less

This Utility

28.9 ppb

National Average

8.66 ppb

State Average

4.86 ppb

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 billion

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Ion Exchange

Toluene

This Utility: 0.233 ppb

EWG's Health Guideline: 150 ppb

Toluene

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

150 ppb or less

This Utility

0.233 ppb

Legal Limit

1,000 ppb

National Average

0.00604 ppb

State Average

0.00362 ppb

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.

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 billion

Pollution Sources

Industry

Filtering Options

Activated Carbon

Reverse Osmosis

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

Find A Filter

Utility: 

Medfield Estates S/d
view utility

Carbon Filters

FILTERS 6 contaminants exceeding guidelines (+3 others)

Can reduce the levels of many common contaminants.

pros

  • Lower upfront cost
  • Reduced maintenance

cons

  • Does not remove all contaminants

Reverse Osmosis

FILTERS 9 contaminants exceeding guidelines (+4 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
Bromodichloromethane
Chloroform
Dibromochloromethane
Dichloroacetic acid
Haloacetic acids (HAA5)
Nitrate
Nitrate & nitrite
Radium, combined (-226 & -228)
Total trihalomethanes (TTHMs)
OTHER CONTAMINANTS DETECTED activated carbon reverse osmosis ion exchange
Chlordane
Fluoride
Heptachlor epoxide
Manganese
Toluene