Bromodichloromethane

Stockton Water Department

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	ND	4	0	ND
2015	0.265 ppb	4	3	ND - 0.510 ppb
2016	0.700 ppb	2	2	0.500 ppb - 0.900 ppb
2017	0.500 ppb	2	2	0.300 ppb - 0.700 ppb
2018	0.625 ppb	4	4	0.300 ppb - 1.30 ppb
2019	0.550 ppb	2	2	0.300 ppb - 0.800 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
2014-07-09	L5104502-1	ND
2014-07-09	L5104502-2	ND
2014-09-30	L2618479-2	ND
2014-09-30	L2618479-1	ND
2015-09-25	L5639837-1	0.150 ppb
2015-09-25	L5639790-1	ND
2015-09-29	L5808596-1	0.510 ppb
2015-09-29	L5808596-2	0.400 ppb
2016-11-04	L6440902-1	0.900 ppb
2016-11-04	L6440902-2	0.500 ppb
2017-09-07	L6944960-2	0.700 ppb
2017-09-07	L6944960-1	0.300 ppb
2018-07-05	L7041014-1	0.500 ppb
2018-07-05	L7041054-1	0.300 ppb
2018-09-07	L7062808-2	1.30 ppb
2018-09-07	L7062808-1	0.400 ppb
2019-09-10	L7153740-2	0.800 ppb
2019-09-10	L7153740-1	0.300 ppb