Bromodichloromethane

Stoughton Waterworks

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

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	0.323 ppb	6	2	ND - 1.20 ppb
2015	1.75 ppb	2	2	1.40 ppb - 2.10 ppb
2016	0.795 ppb	2	2	0.730 ppb - 0.860 ppb
2017	0.500 ppb	5	2	ND - 1.30 ppb
2018	1.25 ppb	2	2	0.590 ppb - 1.90 ppb
2019	1.90 ppb	2	2	1.50 ppb - 2.30 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
2014-03-05	773163	ND
2014-03-05	773172	ND
2014-03-05	773166	ND
2014-03-05	773169	ND
2014-07-23	805340	1.20 ppb
2014-08-11	809428	0.740 ppb
2015-08-19	878029	1.40 ppb
2015-08-19	878028	2.10 ppb
2016-07-27	935782	0.860 ppb
2016-07-27	935783	0.730 ppb
2017-04-26	985399	ND
2017-04-26	985404	ND
2017-05-02	986309	ND
2017-08-02	1008451	1.20 ppb
2017-08-02	1008452	1.30 ppb
2018-07-16	1067520	0.590 ppb
2018-07-16	1067519	1.90 ppb
2019-07-09	1133097	1.50 ppb
2019-07-09	1133098	2.30 ppb