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EWG's Tap Water Database — 2019 UPDATE

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Chloroform

Cedar City Waterworks

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. Read More.

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

 

19

Samples

0

Samples exceeding legal limit (MCL)

11

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.850 ppb220.800 ppb - 0.900 ppb
20130.700 ppb21ND - 1.40 ppb
20140.425 ppb43ND - 0.700 ppb
20150.300 ppb21ND - 0.600 ppb
20160.317 ppb62ND - 1.10 ppb
20172.67 ppb32ND - 7.00 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Result
2012-09-180.800 ppb
2012-09-180.900 ppb
2013-08-221.40 ppb
2013-08-22ND
2014-08-26ND
2014-08-260.700 ppb
2014-11-260.500 ppb
2014-11-260.500 ppb
2015-09-15ND
2015-09-150.600 ppb
2016-06-140.800 ppb
2016-06-14ND
2016-06-14ND
2016-06-14ND
2016-06-14ND
2016-06-141.10 ppb
2017-05-15ND
2017-10-301.000 ppb
2017-10-307.00 ppb