Bromodichloromethane

Bristol County Water Authority

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.

MORE ABOUT THIS CONTAMINANT

131

Samples

Samples exceeding legal limit (MCL)

108

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	4.49 ppb	22	18	ND - 7.01 ppb
2015	1.54 ppb	5	1	ND - 7.70 ppb
2016	ND	4	0	ND
2017	3.06 ppb	26	22	ND - 4.90 ppb
2018	3.12 ppb	39	35	ND - 5.60 ppb
2019	3.30 ppb	35	32	ND - 5.40 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.06 ppb

The EWG Health Guideline of 0.06 ppb for bromodichloromethane 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
2014-01-21	1401190-04_TO12	ND
2014-01-21	1401190-03_TO12	ND
2014-01-21	1401190-02_TO12	ND
2014-02-19	1401528-07_TO02	5.95 ppb
2014-02-19	1401528-08_TO02	5.12 ppb
2014-02-20	1401528-09_TO02	4.72 ppb
2014-02-20	1401528-01_TO02	4.74 ppb
2014-02-20	1401528-02_TO02	6.38 ppb
2014-02-20	1401528-03_TO02	5.21 ppb
2014-02-20	1401528-05_TO02	4.27 ppb
2014-02-20	1401528-06_TO02	5.31 ppb
2014-02-20	1401528-04_TO02	4.50 ppb
2014-03-19	1401911-01_TO02	6.37 ppb
2014-03-19	1401911-02_TO02	5.81 ppb
2014-03-19	1401911-03_TO02	5.15 ppb
2014-03-19	1401911-05_TO02	5.39 ppb
2014-03-19	1401911-06_TO02	6.09 ppb
2014-03-19	1401911-08_TO02	5.78 ppb
2014-03-19	1401911-04_TO02	5.58 ppb
2014-03-20	1401911-07_TO02	7.01 ppb
2014-03-20	1401911-09_TO02	5.30 ppb
2014-09-08	1404927-01_TO12	ND
2015-01-05	1501009-03_TO12	ND
2015-01-05	1501009-02_TO12	ND
2015-01-05	1501009-04_TO12	ND
2015-07-17	1503203-01_TO12	ND
2015-12-30	1512733-01_TO12	7.70 ppb
2016-03-09	1601434-04_TO12	ND
2016-03-09	1601434-03_TO12	ND
2016-03-09	1601434-02_TO12	ND
2016-07-19	1603486-01_TO12	ND
2017-01-31	1701087-04_TO12	ND
2017-01-31	1701087-03_TO12	ND
2017-01-31	1701087-02_TO12	ND
2017-08-15	1708371-01	2.90 ppb
2017-08-15	1708371-02	4.90 ppb
2017-08-15	1708371-04	3.20 ppb
2017-08-15	1708371-06	3.30 ppb
2017-08-15	1708371-07	3.20 ppb
2017-08-15	1708371-08	3.50 ppb
2017-08-15	1708371-09	2.50 ppb
2017-08-15	1708371-10	2.80 ppb
2017-08-16	1708371-11	2.00 ppb
2017-08-16	1708371-03	3.80 ppb
2017-08-16	1708371-05	3.30 ppb
2017-08-16	1703873-02_TO12	ND
2017-11-21	1711644-01	3.80 ppb
2017-11-21	1711644-02	4.70 ppb
2017-11-21	1711644-03	4.30 ppb
2017-11-21	1711644-04	4.10 ppb
2017-11-21	1711644-05	4.30 ppb
2017-11-21	1711644-06	4.20 ppb
2017-11-21	1711644-07	4.30 ppb
2017-11-21	1711644-10	3.60 ppb
2017-11-21	1711644-09	3.50 ppb
2017-11-22	1711644-08	3.70 ppb
2017-11-22	1711644-11	3.60 ppb
2018-01-09	1800842-03_TO12	ND
2018-01-09	1800842-02_TO12	ND
2018-01-09	1800842-01_TO12	ND
2018-02-20	1802398-01	3.50 ppb
2018-02-20	1802398-02	5.60 ppb
2018-02-20	1802398-03	3.70 ppb
2018-02-20	1802398-04	3.60 ppb
2018-02-20	1802398-05	3.50 ppb
2018-02-20	1802398-06	5.40 ppb
2018-02-20	1802398-07	3.80 ppb
2018-02-20	1802398-08	4.00 ppb
2018-02-20	1802398-09	3.20 ppb
2018-02-21	1802398-11	2.70 ppb
2018-02-21	1802398-10	3.20 ppb
2018-05-15	1805423-01	3.10 ppb
2018-05-15	1805423-02	4.30 ppb
2018-05-15	1805423-03	3.40 ppb
2018-05-15	1805423-04	3.20 ppb
2018-05-15	1805423-05	3.20 ppb
2018-05-15	1805423-06	3.80 ppb
2018-05-15	1805423-07	3.10 ppb
2018-05-15	1805423-08	3.50 ppb
2018-08-21	1808574-01	2.70 ppb
2018-08-21	1808574-02	3.90 ppb
2018-08-21	1808575-01	2.80 ppb
2018-08-21	1808575-02	5.00 ppb
2018-08-21	1808575-03	3.60 ppb
2018-08-21	1808575-04	2.80 ppb
2018-08-22	1808575-05	2.70 ppb
2018-08-22	1808575-06	3.80 ppb
2018-08-31	1803935-01_TO12	ND
2018-11-20	1811558-01	3.00 ppb
2018-11-20	1811558-02	4.60 ppb
2018-11-20	1811558-03	3.10 ppb
2018-11-20	1811558-04	2.80 ppb
2018-11-20	1811558-05	2.50 ppb
2018-11-20	1811558-06	3.00 ppb
2018-11-20	1811558-07	2.50 ppb
2018-11-20	1811558-08	3.20 ppb
2019-01-22	1900905-02_TO12	ND
2019-01-22	1900905-03_TO12	ND
2019-01-22	1900905-04_TO12	ND
2019-02-19	1902390-01	3.10 ppb
2019-02-19	1902390-02	4.70 ppb
2019-02-19	1902390-03	3.80 ppb
2019-02-19	1902390-04	5.40 ppb
2019-02-19	1902390-06	4.50 ppb
2019-02-19	1902390-07	3.40 ppb
2019-02-19	1902390-08	3.30 ppb
2019-02-20	1902390-05	3.00 ppb
2019-05-21	1905740-01	2.30 ppb
2019-05-21	1905740-02	3.20 ppb
2019-05-21	1905740-03	2.90 ppb
2019-05-21	1905740-04	2.40 ppb
2019-05-21	1905740-05	2.50 ppb
2019-05-21	1905740-06	3.50 ppb
2019-05-21	1905740-07	2.60 ppb
2019-05-21	1905740-08	3.00 ppb
2019-08-20	19H0643-01	2.70 ppb
2019-08-20	19H0643-02	4.00 ppb
2019-08-20	19H0643-03	3.40 ppb
2019-08-20	19H0643-04	2.90 ppb
2019-08-20	19H0643-05	2.80 ppb
2019-08-20	19H0643-06	4.90 ppb
2019-08-20	19H0643-07	3.20 ppb
2019-08-20	19H0643-08	3.90 ppb
2019-11-19	19K0600-01	3.40 ppb
2019-11-19	19K0600-02	5.40 ppb
2019-11-19	19K0600-03	4.80 ppb
2019-11-19	19K0600-04	4.10 ppb
2019-11-19	19K0600-05	3.20 ppb
2019-11-19	19K0600-06	5.40 ppb
2019-11-19	19K0600-07	3.90 ppb
2019-11-19	19K0600-08	3.90 ppb