Know Your Environment. Protect Your Health.

UTILITY

Natchitoches Water System

location

Natchitoches, Louisiana

serves

29,334

source

Surface water

data

2013-2023

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 Louisiana Department of Health and Hospitals, 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

Arsenic

Potential Effect: cancer

This Utility: 1.48 ppb

371x

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 371 times above EWG's Health Guideline.

EWG Health Guideline

0.004 ppb or less

This Utility

1.48 ppb

Legal Limit

10 ppb

National Average

0.624 ppb

State Average

0.423 ppb

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 billion

Pollution Sources

Agriculture

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Bromodichloromethane

Potential Effect: cancer

This Utility: 6.75 ppb

112x

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 112 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

6.75 ppb

National Average

5.89 ppb

State Average

6.58 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: 19.1 ppb

48x

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 48 times above EWG's Health Guideline.

EWG Health Guideline

0.4 ppb or less

This Utility

19.1 ppb

National Average

16.2 ppb

State Average

14.7 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

Chromium (hexavalent)

Potential Effect: cancer

This Utility: 0.0608 ppb

3x

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 3 times above EWG's Health Guideline.

EWG Health Guideline

0.02 ppb or less

This Utility

0.0608 ppb

National Average

0.44 ppb

State Average

0.112 ppb

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 billion

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Dibromoacetic acid

Potential Effect:

This Utility: 1.87 ppb

62x

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 62 times above EWG's Health Guideline.

EWG Health Guideline

0.03 ppb or less

This Utility

1.87 ppb

National Average

1.13 ppb

State Average

1.85 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Dibromochloromethane

Potential Effect: cancer

This Utility: 1.95 ppb

20x

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 20 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

1.95 ppb

National Average

3.55 ppb

State Average

4.49 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: 21.0 ppb

105x

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 105 times above EWG's Health Guideline.

EWG Health Guideline

0.2 ppb or less

This Utility

21 ppb

National Average

8 ppb

State Average

9.07 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: 31.8 ppb

318x

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 318 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

31.8 ppb

Legal Limit

60 ppb

National Average

19.8 ppb

State Average

17.8 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

Haloacetic acids (HAA9)

Potential Effect: cancer

This Utility: 28.6 ppb

477x

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 477 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

28.6 ppb

National Average

23.7 ppb

State Average

21.4 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Total trihalomethanes (TTHMs)

Potential Effect: cancer

This Utility: 27.9 ppb

186x

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 186 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

27.9 ppb

Legal Limit

80 ppb

National Average

29.1 ppb

State Average

28.2 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

Trichloroacetic acid

Potential Effect: cancer

This Utility: 5.48 ppb

55x

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 55 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

5.48 ppb

National Average

6.57 ppb

State Average

5.65 ppb

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 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.


† 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.

Aluminum

This Utility: 361.7 ppb

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

600 ppb or less

This Utility

361.7 ppb

National Average

26.4 ppb

State Average

62.8 ppb

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 billion

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Atrazine

This Utility: 0.0560 ppb

EWG's Health Guideline: 0.1 ppb

Atrazine

Atrazine is a herbicide commonly detected in drinking water that comes from cornfield and other agricultural runoff. It is a hormone disrupter that harms the male and female reproductive systems of people and wildlife.

How your levels compare

EWG Health Guideline

0.1 ppb or less

This Utility

0.056 ppb

Legal Limit

3 ppb

National Average

0.0145 ppb

State Average

0.0405 ppb

Health Risks

The EWG Health Guideline of 0.1 ppb for atrazine was defined by EWG based on epidemiological studies of human exposure to atrazine in drinking water.. This health guideline protects against harm to the developing fetus, harm to the reproductive system and hormone disruption.

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

Bromoform

This Utility: 0.0458 ppb

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

0.5 ppb or less

This Utility

0.0458 ppb

National Average

1.44 ppb

State Average

2.42 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Chlorate

This Utility: 121.6 ppb

EWG's Health Guideline: 210 ppb

Chlorate

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

210 ppb or less

This Utility

121.6 ppb

National Average

116.8 ppb

State Average

123.1 ppb

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.

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

Agriculture

Industry

Treatment Byproducts

Fluoride

This Utility: 0.667 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

0.667 ppm

Legal Limit

4 ppm

National Average

0.49 ppm

State Average

0.383 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

Manganese

This Utility: 46.6 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

46.6 ppb

National Average

8.66 ppb

State Average

42.2 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

Molybdenum

This Utility: 0.238 ppb

EWG's Health Guideline: 40 ppb

Molybdenum

Molybdenum is a metal that occurs naturally in soil, minerals and water. People who ingest large amounts can have increased levels of uric acid and gout-like symptoms.

How your levels compare

EWG Health Guideline

40 ppb or less

This Utility

0.238 ppb

National Average

1.49 ppb

State Average

0.779 ppb

Health Risks

The EWG Health Guideline of 40 ppb for molybdenum was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against metabolic changes and excess formation of uric acid in the blood.

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

Reverse Osmosis

Ion Exchange

Monobromoacetic acid

This Utility: 0.696 ppb

EWG's Health Guideline: 25 ppb

Monobromoacetic acid

Monobromoacetic 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

25 ppb or less

This Utility

0.696 ppb

National Average

0.18 ppb

State Average

0.501 ppb

Health Risks

The EWG Health Guideline of 25 ppb for monobromoacetic 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 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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Monochloroacetic acid

This Utility: 2.74 ppb

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

53 ppb or less

This Utility

2.74 ppb

National Average

0.497 ppb

State Average

0.765 ppb

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 billion

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Nitrate and nitrite

This Utility: 0.167 ppm

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.

How your levels compare

EWG Health Guideline

0.14 ppm or less

This Utility

0.167 ppm

Legal Limit

10 ppm

National Average

0.78 ppm

State Average

0.348 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

Oxamyl (Vydate)

This Utility: 0.0900 ppb

EWG's Health Guideline: 26 ppb

Oxamyl (Vydate)

Oxamyl is a neurotoxic insecticide used on cotton, fruit and vegetable crops. It may harm fetal development.

How your levels compare

EWG Health Guideline

26 ppb or less

This Utility

0.09 ppb

Legal Limit

200 ppb

National Average

0.000676 ppb

State Average

0.000727 ppb

Health Risks

The EWG Health Guideline of 26 ppb for oxamyl 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 central nervous 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 billion

Pollution Sources

Agriculture

Filtering Options

Activated Carbon

Reverse Osmosis

Perfluoroheptanoic acid (PFHPA)

This Utility: 1.55 ppt

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

1,000 ppt or less

This Utility

1.55 ppt

National Average

0.249 ppt

State Average

0.014 ppt

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 trillion

Pollution Sources

Industry

Runoff & Sprawl

Filtering Options

Activated Carbon

Reverse Osmosis

Radium, combined (-226 and -228)

This Utility: 0.08 pCi/L

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.

How your levels compare

EWG Health Guideline

0.05 pCi/L or less

This Utility

0.08 pCi/L

Legal Limit

5 pCi/L

National Average

0.33 pCi/L

State Average

0.23 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

Strontium

This Utility: 0.114 ppb

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

1,500 ppb or less

This Utility

0.114 ppb

National Average

0.488 ppb

State Average

0.131 ppb

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 billion

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Vanadium

This Utility: 0.616 ppb

EWG's Health Guideline: 21 ppb

Vanadium

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

21 ppb or less

This Utility

0.616 ppb

National Average

1.54 ppb

State Average

0.721 ppb

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.

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

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-Trichloroethane, 1,1,2-Trichloroethane, 1,1-Dichloroethane, 1,1-Dichloroethylene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2-Dibromo-3-chloropropane (DBCP), 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3-Butadiene, 1,4-Dioxane, 1-butanol, 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic aci, 2,3,7,8-TCDD (Dioxin), 2,4,5-TP (Silvex), 2,4-D, 2-methoxyethanol, 2-propen-1-ol, 4,8-dioxa-3H-perfluorononanoic acid (ADONA), 4:2 Fluorotelomer sulfonate (4:2 FTS), 4:2 Fluorotelomer Sulfonic Acid (4:2 FTSA), 6:2 Fluorotelomer sulfonate (6:2FTS), 6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA), 8:2 Fluorotelomer sulfonate (8:2FTS), 8:2 Fluorotelomer Sulfonic Acid (8:2 FTSA), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (, Alachlor (Lasso), Alpha-hexachlorocyclohexane, Antimony, Asbestos, Benzene, Benzo[a]pyrene, Beryllium, Bromochloromethane, Bromomethane, Butanoic acid, 2,2,3,3,4,4-hexafluoro-4-(trifluoro, Butylated hydroxyanisole, Cadmium, Carbofuran, Chlordane, Chlorodifluoromethane, Chloromethane, Chlorpyriphos, Chromium (total), cis-1,2-Dichloroethylene, Cobalt, Combined uranium, Cyanide, Dalapon, Di(2-ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Dichloromethane (methylene chloride), Dimethipin, Dinoseb, Diquat, Endothall, Endrin, Ethoprop, Ethylbenzene, Ethylene dibromide, Germanium, Glyphosate, Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorocyclopentadiene, Hexafluoropropylene oxide dimer acid (HFPO-DA), Lindane, Lithium, Mercury (inorganic), Methoxychlor, Monochlorobenzene (chlorobenzene), N-ethyl perfluorooctane sulfonamido acetic acid (N, N-methyl perfluorooctanesulfonamidoacetic acid, Nonafluoro-3,6-dioxaheptanoic acid, o-Dichlorobenzene, o-toluidine, Oxyflurofen, p-Dichlorobenzene, Pentachlorophenol, Perfluoro(2-ethoxyethane)sulfonic acid, Perfluorobutane sulfonate (PFBS), Perfluorobutanoic acid (PFBA), Perfluorodecanoic acid (PFDA), Perfluorododecanoic acid (PFDoA), Perfluoroheptane sulfonic acid (PFHpS), Perfluorohexane sulfonate (PFHXS), Perfluorohexanoic Acid (PFHxA), Perfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA), Perfluoropentane sulfonic acid (PFPeS), Perfluoropentanoic acid (PFPeA), Perfluorotetradecanoic acid (PFTA), Perfluorotridecanoic acid (PFTrDA), Perfluoroundecanoic acid (PFUnA), Permethrin, Picloram, Polychlorinated biphenyls (PCBs), Profenofos, Propanoic acid, 2,2,3,3-tetrafluoro-3-(trifluorome, Quinoline, Selenium, Silver, Simazine, Styrene, Tebuconazole, Tetrachloroethylene (perchloroethylene), Thallium, Toluene, Toxaphene, trans-1,2-Dichloroethylene, Tribufos, Trichloroethylene, Vinyl chloride, Xylenes (total)

Find A Filter

Utility: 

Natchitoches Water System
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Carbon Filters

FILTERS 9 contaminants exceeding guidelines (+6 others)

Can reduce the levels of many common contaminants.

pros

  • Lower upfront cost
  • Reduced maintenance

cons

  • Does not remove all contaminants

Reverse Osmosis

FILTERS 11 contaminants exceeding guidelines (+12 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)
Total trihalomethanes (TTHMs)
Trichloroacetic acid
OTHER CONTAMINANTS DETECTED activated carbon reverse osmosis ion exchange
Aluminum
Atrazine
Bromoform
Chlorate
Fluoride
Manganese
Molybdenum
Monobromoacetic acid
Monochloroacetic acid
Nitrate & nitrite
Oxamyl (Vydate)
Perfluoroheptanoic acid (PFHPA)
Radium, combined (-226 & -228)
Strontium
Vanadium