Dibromochloromethane

Wards 4 & 5 Water System

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.

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
2014	0.375 ppb	8	2	ND - 1.50 ppb
2015	ND	4	0	ND
2016	1.05 ppb	4	2	ND - 2.10 ppb
2017	1.65 ppb	4	4	1.60 ppb - 1.70 ppb
2018	ND	4	0	ND
2019	2.50 ppb	4	4	2.00 ppb - 3.00 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
2014-03-31	AD90270	ND
2014-03-31	AD90269	ND
2014-03-31	AD90270	ND
2014-03-31	AD90269	ND
2014-09-04	L0048048-01	ND
2014-09-04	L0048048-01	ND
2014-09-04	L0048048-02	1.50 ppb
2014-09-04	L0048048-02	1.50 ppb
2015-09-02	35206348001	ND
2015-09-02	35206348002	ND
2015-09-02	35206348002	ND
2015-09-02	35206348001	ND
2016-09-08	LA25170-1	2.10 ppb
2016-09-08	LA25170-2	ND
2016-09-08	LA25170-2	ND
2016-09-08	LA25170-1	2.10 ppb
2017-09-14	35335598004	1.60 ppb
2017-09-14	35335598004	1.60 ppb
2017-09-14	35335598003	1.70 ppb
2017-09-14	35335598003	1.70 ppb
2018-09-12	35417620002	ND
2018-09-12	35417620001	ND
2018-09-12	35417620001	ND
2018-09-12	35417620002	ND
2019-09-20	35499540001	3.00 ppb
2019-09-20	35499540002	2.00 ppb
2019-09-20	35499540001	3.00 ppb
2019-09-20	35499540002	2.00 ppb