Bromoform

Valley Falls, City of

Bromoform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromoform 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	0.690 ppb	4	3	ND - 1.40 ppb
2016	0.775 ppb	4	4	0.510 ppb - 1.20 ppb
2017	0.680 ppb	4	4	0.600 ppb - 0.750 ppb
2018	1.16 ppb	4	4	0.620 ppb - 1.40 ppb
2019	0.270 ppb	4	2	ND - 0.580 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.5 ppb

The EWG Health Guideline of 0.5 ppb for bromoform 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
2014-02-09	52846	ND
2014-05-04	105500	ND
2014-08-18	174754	ND
2014-11-17	232379	ND
2015-02-16	279526	0.720 ppb
2015-05-18	334148	ND
2015-08-17	388586	0.640 ppb
2015-11-16	428025	1.40 ppb
2016-02-15	493184	0.680 ppb
2016-05-23	550691	0.710 ppb
2016-08-22	607453	1.20 ppb
2016-11-15	660113	0.510 ppb
2017-02-20	710818	0.700 ppb
2017-05-15	761415	0.670 ppb
2017-08-21	823056	0.750 ppb
2017-11-20	880474	0.600 ppb
2018-02-19	907925	1.30 ppb
2018-05-21	973332	1.30 ppb
2018-08-21	1029095	1.40 ppb
2018-11-19	1079291	0.620 ppb
2019-02-18	1122466	ND
2019-05-20	1157728	ND
2019-08-19	1225672	0.500 ppb
2019-11-19	1277508	0.580 ppb