Dibromochloromethane
Flora
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.
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 | 1.64 ppb | 8 | 8 | 0.714 ppb - 2.88 ppb |
| 2015 | 2.23 ppb | 8 | 8 | 0.699 ppb - 5.06 ppb |
| 2016 | 0.777 ppb | 8 | 6 | ND - 1.36 ppb |
| 2017 | 0.985 ppb | 8 | 8 | 0.699 ppb - 1.19 ppb |
| 2018 | 0.491 ppb | 8 | 6 | ND - 0.807 ppb |
| 2019 | 0.695 ppb | 8 | 6 | ND - 1.21 ppb |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 0.1 ppb
The EWG Health Guideline of 0.1 ppb for dibromochloromethane 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 |
|---|---|---|
| 2014-02-06 | 4020755-01 | 1.30 ppb |
| 2014-02-06 | 4020755-02 | 1.34 ppb |
| 2014-05-07 | 4051189-01 | 0.714 ppb |
| 2014-05-07 | 4051189-02 | 0.720 ppb |
| 2014-08-05 | 4080859-01 | 1.66 ppb |
| 2014-08-05 | 4080859-02 | 1.64 ppb |
| 2014-11-05 | 4110917-01 | 2.88 ppb |
| 2014-11-05 | 4110917-02 | 2.85 ppb |
| 2015-02-10 | 5021590-01 | 5.00 ppb |
| 2015-02-10 | 5021590-02 | 5.06 ppb |
| 2015-05-06 | 5051034-01 | 0.699 ppb |
| 2015-05-06 | 5051034-02 | 2.86 ppb |
| 2015-08-04 | 5080582-01 | 1.22 ppb |
| 2015-08-04 | 5080582-02 | 1.07 ppb |
| 2015-11-09 | 5111508-01 | 0.978 ppb |
| 2015-11-09 | 5111508-02 | 0.951 ppb |
| 2016-02-09 | 6021605-02 | ND |
| 2016-02-09 | 6021605-01 | ND |
| 2016-05-03 | 6050554-01 | 0.824 ppb |
| 2016-05-03 | 6050554-02 | 1.01 ppb |
| 2016-08-02 | 6080413-01 | 1.15 ppb |
| 2016-08-02 | 6080413-02 | 1.36 ppb |
| 2016-11-02 | 6110647-01 | 0.934 ppb |
| 2016-11-02 | 6110647-02 | 0.940 ppb |
| 2017-02-06 | 7020894-01 | 0.699 ppb |
| 2017-02-06 | 7020894-02 | 0.738 ppb |
| 2017-05-01 | 7050255-01 | 1.12 ppb |
| 2017-05-01 | 7050255-02 | 1.08 ppb |
| 2017-08-01 | 7080445-01 | 1.17 ppb |
| 2017-08-01 | 7080445-02 | 1.19 ppb |
| 2017-11-07 | 7111525-01 | 0.955 ppb |
| 2017-11-07 | 7111525-02 | 0.924 ppb |
| 2018-02-06 | 8020977-02 | 0.638 ppb |
| 2018-02-06 | 8020977-01 | 0.654 ppb |
| 2018-05-08 | 8051830-01 | ND |
| 2018-05-08 | 8051830-02 | ND |
| 2018-08-07 | 8081518-01 | 0.807 ppb |
| 2018-08-07 | 8081518-02 | 0.763 ppb |
| 2018-11-06 | 8111189-01 | 0.525 ppb |
| 2018-11-06 | 8111189-02 | 0.543 ppb |
| 2019-02-05 | 9020916-01 | ND |
| 2019-02-05 | 9020916-02 | ND |
| 2019-05-07 | 9051776-01 | 0.704 ppb |
| 2019-05-07 | 9051776-02 | 0.694 ppb |
| 2019-08-06 | 9081442-01 | 1.21 ppb |
| 2019-08-06 | 9081442-02 | 1.14 ppb |
| 2019-11-05 | 9110877-02 | 0.934 ppb |
| 2019-11-05 | 9110877-01 | 0.881 ppb |