Bromodichloromethane

Lyon County Rural Water District 1

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
2014	6.00 ppb	4	1	ND - 24.0 ppb
2015	0.350 ppb	4	1	ND - 1.40 ppb
2016	0.165 ppb	4	1	ND - 0.660 ppb
2017	0.250 ppb	4	1	ND - 1.000 ppb
2018	15.5 ppb	4	2	ND - 39.0 ppb
2019	0.148 ppb	4	1	ND - 0.590 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
2014-01-15	36913	ND
2014-04-20	117306	24.0 ppb
2014-07-15	152128	ND
2014-10-14	213557	ND
2015-01-20	264450	ND
2015-04-14	312994	ND
2015-08-11	382002	ND
2015-10-21	421451	1.40 ppb
2016-01-19	478105	ND
2016-04-26	533462	ND
2016-07-19	586034	ND
2016-10-18	644963	0.660 ppb
2017-01-17	679808	ND
2017-04-18	744004	ND
2017-08-07	814114	ND
2017-10-17	862884	1.000 ppb
2018-01-16	907870	23.0 ppb
2018-04-17	938165	ND
2018-07-17	1007951	39.0 ppb
2018-11-14	1076984	ND
2019-01-15	1106234	ND
2019-04-09	1139008	ND
2019-08-20	1225832	0.590 ppb
2019-11-13	1274498	ND