Chloroform in tap water

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48
States Affected
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227
Million
People Affected
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6/10
Toxicity Rating
Health Effects

Elevated exposure to chloroform is often associated with brain, kidney, and liver damage including hepatitis and jaundice. It has also been linked to pregnancy problems. Exposure can cause dizziness, irritability, headaches, fatigue, and more. Chloroform is suspected of causing cancer.

The legal limit is
Health Guideline
0.4 ppb
200x
what is considered unhealthy
Legal Limit
80 ppb
What is chloroform?
A famous anesthetic in the 19th century, Chloroform is a dangerous chemical used to make other chemicals. Chloroform can be ingested, inhaled, or absorbed through the skin and is suspected of causing cancer. Chloroform is one of four specific disinfection byproducts (DBPs) classified as trihalomethanes and one of the most common DBPs in drinking water.
What are disinfection byproducts (DBPs)?
DBPs are the result of chemical reactions that occur when water interacts with disinfection agents such as chlorine. Hundreds of DBPs exist, but trihalomethanes (TTHMs), haloacetic acids (HAAs), chlorite, and bromate are common DBPs associated with tap water.
DBPs vary based on a variety of factors including water quality as well as the disinfectants used to treat water. The U.S. EPA has set Maximum Contaminant Levels (MCLs) for TTHMs, HAA5, chlorite, and bromate to regulate the volume of these DBPs found in drinking water supplies. The U.S. Food and Drug Administration (FDA) set allowable levels of TTHMs, HAA5, chlorite, and bromate to regulate the volume of these DBPs found in bottled water.
Why is chloroform in tap water? How does it get into tap water?
Chloroform is typically found in tap water when chlorine and other disinfectant agents interact with water supplies being treated for public consumption. 98% of tap water supplies in the U.S. are treated with chlorine. The amount of chlorine used constantly changes in response to new and emerging contaminants, damaged and aging systems, and natural disasters like flooding and fires. This change in chlorine levels can increase levels of chloroform. Plus, as other disinfectants are added, removed, and adjusted, chloroform can increase.
Given chloroform is used to make other chemicals, it can also be found at paper mills, hazardous waste sites, and landfills. The colorless liquid dissolves easily into water which means it can sneak into water supplies undetected if mismanaged by the aforementioned resources.
Why is chloroform in my tap water harmful?
Chloroform is on the EPA’s list of “extremely hazardous substances.” Elevated exposure to chloroform is often associated with brain, kidney, and liver damage including hepatitis and jaundice. It has also been linked to pregnancy problems. Exposure can cause dizziness, irritability, headaches, fatigue, and more.
Chloroform is suspected of causing cancer. The chemical is classified as “possibly carcinogenic to humans” by the International Agency for Research on Cancer (IARC). Plus, the latest ‘Report on Carcinogens’ from the U.S. Department of Health and Human Services labeled chloroform as “reasonably anticipated to be a human carcinogen.” In other words, multiple organizations believe it could have the potential to cause cancer in humans.
Is chloroform illegal?
Chloroform has been banned as a consumer product in the United States since 1976. That means you cannot buy chloroform.
How much chloroform is safe in water?
Chloroform is part of a family of four trihalomethanes that are regulated by the U.S. EPA as a group. This group is referred to by the acronym TTHMs, which stands for total trihalomethanes. The U.S. EPA set a Maximum Contaminant Level (MCL) of .080 mg/L, or 80 parts-per-billion (ppb), for TTHMs in public water supplies. Water is sampled quarterly to form an annual average. Therefore, chloroform can exceed the MCL at any given time.
Chloroform has also been assigned its own Maximum Contaminant Level Goal (MCLG) of .07 mg/L, or 70 ppb, by the U.S. EPA. The MCLG is defined as the level of a contaminant in drinking water below which there is no known or expected health risk. This MCLG is not an enforceable standard.
What can I do about chloroform in my tap water?
Clearly Filtered’s breakthrough Affinity® Filtration Technology removes up to 99.9% of chloroform from your tap water. Upgrade to our superior water filters so you never have to worry about chloroform lurking in your water again.
How does Clearly Filtered do at Removing Chloroform in tap water?
Clearly Filtered with
Affinity Filtration Technology Product
Water Pitcher Filter
Under-the-Sink FIlter
Water Bottle Filter
Refrigerator Filter
Chloroform in tap water Removal
>99.8%
98.4%
>99.9%
98.4%
References

1. U.S. EPA. National Primary Drinking Water Regulations. https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations#Byproducts. Accessed April 1, 2021. 

2. EWG Tap Water Database. Chloroform. https://www.ewg.org/tapwater/contaminant.php?contamcode=2941#. Accessed April 1, 2021. 

3. World Health Organization. Trihalomethanes in Drinking-water. https://www.who.int/water_sanitation_health/dwq/chemicals/THM200605.pdf. Accessed April 1, 2021. 

4. CDC. Biomonitoring Summary: Disinfection By-Products (Trihalomethanes). https://www.cdc.gov/biomonitoring/THM-DBP_BiomonitoringSummary.html. Accessed April 1, 2021. 

5. IARC. Monographs On The Identification of Carcinogenic Hazards to Humans: List of Classifications.  https://monographs.iarc.who.int/list-of-classifications. Accessed April 1, 2021. 

6. NTP. Report on Carcinogens (ROC), Fourteenth Edition: Chloroform. https://ntp.niehs.nih.gov/ntp/roc/content/profiles/chloroform.pdf. Accessed April 1, 2021. 

7. EPA. Chloroform. https://www.epa.gov/sites/production/files/2016-09/documents/chloroform.pdf. Accessed April 1, 2021. 

8. EWG. 220 Million Americans Could Have Chloroform in Their Tap Water. https://www.ewg.org/news-insights/news/220-million-americans-could-have-chloroform-their-tap-water#.WbvYfdOGOL5. Accessed April 1, 2021.