Chloroform
Dewitt WDS - South
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 30.0 ppb | 8 | 8 | 16.0 ppb - 47.0 ppb |
| 2015 | 28.9 ppb | 8 | 8 | 13.0 ppb - 43.0 ppb |
| 2016 | 26.0 ppb | 8 | 8 | 9.90 ppb - 45.0 ppb |
| 2017 | 36.7 ppb | 6 | 6 | 24.0 ppb - 60.0 ppb |
| 2018 | 28.5 ppb | 8 | 8 | 18.0 ppb - 38.0 ppb |
| 2019 | 35.3 ppb | 8 | 8 | 26.0 ppb - 55.0 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 | Lab ID | Result |
|---|---|---|
| 2014-02-13 | 1Q2014 CORONATIO | 34.0 ppb |
| 2014-02-13 | 1Q2014 JD EDINGE | 16.0 ppb |
| 2014-05-13 | 2Q2014 CORONATIO | 29.0 ppb |
| 2014-05-13 | 2Q2014 JD EDINGE | 23.0 ppb |
| 2014-08-13 | 3Q2014 JD EDINGE | 26.0 ppb |
| 2014-08-13 | 3Q2014 CORONATIO | 38.0 ppb |
| 2014-11-13 | 4Q2014 JD EDINGE | 27.0 ppb |
| 2014-11-13 | 4Q2014 CORONATIO | 47.0 ppb |
| 2015-02-11 | 1Q2015 CORONATIO | 35.0 ppb |
| 2015-02-11 | 1Q2015 JD EDINGE | 13.0 ppb |
| 2015-05-14 | 2Q2015 JD EDINGE | 18.0 ppb |
| 2015-05-14 | 2Q2015 CORONATIO | 33.0 ppb |
| 2015-08-13 | 3Q2015 JD EDINGE | 24.0 ppb |
| 2015-08-13 | 3Q2015 CORONATIO | 37.0 ppb |
| 2015-11-09 | 4Q2015 JD EDINGE | 28.0 ppb |
| 2015-11-09 | 4Q2015 CORONATIO | 43.0 ppb |
| 2016-02-12 | 1Q2016 JD EDINGE | 15.0 ppb |
| 2016-02-12 | 1Q2016 CORONATIO | 9.90 ppb |
| 2016-05-17 | 2Q2016 JD EDINGE | 19.0 ppb |
| 2016-05-17 | 2Q2016 CORONATIO | 32.0 ppb |
| 2016-08-10 | 3Q2016 CORONATIO | 45.0 ppb |
| 2016-08-10 | 3Q2016 JD EDINGE | 24.0 ppb |
| 2016-11-08 | 4Q2016 JD EDINGE | 25.0 ppb |
| 2016-11-08 | 4Q2016 CORONATIO | 38.0 ppb |
| 2017-05-10 | 2Q2017 JD EDINGE | 30.0 ppb |
| 2017-05-10 | 2Q2017 CORONATIO | 34.0 ppb |
| 2017-08-09 | 3Q2017 CORONATIO | 60.0 ppb |
| 2017-08-09 | 3Q2017 JD EDINGE | 37.0 ppb |
| 2017-11-07 | 4Q2017 JD EDINGE | 24.0 ppb |
| 2017-11-07 | 4Q2017 CORONATIO | 35.0 ppb |
| 2018-02-15 | 1Q2018 EDINGER D | 18.0 ppb |
| 2018-02-15 | 1Q2018 CORONATIO | 24.0 ppb |
| 2018-05-10 | 2Q2018 JD EDINGE | 25.0 ppb |
| 2018-05-10 | 2Q2018 CORONATIO | 34.0 ppb |
| 2018-08-16 | 3Q2018 JD EDINGE | 29.0 ppb |
| 2018-08-16 | 3Q2018 CORONATIO | 38.0 ppb |
| 2018-11-07 | 4Q2018 JD EDINGE | 25.0 ppb |
| 2018-11-17 | 4Q2018 CORONATIO | 35.0 ppb |
| 2019-02-14 | 1Q2019 CORONATIO | 36.0 ppb |
| 2019-02-14 | 1Q2019 JD EDINGE | 26.0 ppb |
| 2019-05-10 | 2Q2019 CORONATIO | 36.0 ppb |
| 2019-05-10 | 2Q2019 JD EDINGE | 30.0 ppb |
| 2019-08-13 | 3Q2019 JD EDINGE | 34.0 ppb |
| 2019-08-13 | 3Q2019 CORONATIO | 55.0 ppb |
| 2019-11-06 | 4Q2019 CORONATIO | 39.0 ppb |
| 2019-11-06 | 4Q2019 JD EDINGE | 26.0 ppb |