Bromoform

Monona Waterworks

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	0.126 ppb	5	1	ND - 0.630 ppb
2015	0.672 ppb	5	3	ND - 1.60 ppb
2016	0.656 ppb	5	3	ND - 1.70 ppb
2017	0.486 ppb	5	4	ND - 0.800 ppb
2018	0.455 ppb	2	2	0.330 ppb - 0.580 ppb
2019	0.500 ppb	2	1	ND - 1.000 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
2014-09-02	154323001	ND
2014-09-02	154276001	ND
2014-09-05	155135001	ND
2014-09-25	159907001	ND
2014-12-12	172471001	0.630 ppb
2015-01-30	177607001	ND
2015-06-16	199937001	ND
2015-07-14	205376001	0.970 ppb
2015-07-14	205378001	1.60 ppb
2015-11-17	228870001	0.790 ppb
2016-02-01	237611001	ND
2016-04-06	247252001	0.890 ppb
2016-07-07	264567001	ND
2016-09-28	280796001	1.70 ppb
2016-10-20	285154001	0.690 ppb
2017-03-30	306799001	0.800 ppb
2017-04-13	309656001	ND
2017-04-13	309655001	0.450 ppb
2017-04-13	309654001	0.630 ppb
2017-09-22	344258001	0.550 ppb
2018-07-11	393604001	0.330 ppb
2018-09-25	410134001	0.580 ppb
2019-04-24	442084001	ND
2019-09-05	467810001	1.000 ppb