Bromoform

Harlem, 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	5	0	ND
2015	ND	4	0	ND
2016	0.530 ppb	3	2	ND - 0.820 ppb
2017	0.167 ppb	3	1	ND - 0.500 ppb
2018	0.450 ppb	6	3	ND - 1.60 ppb
2019	1.03 ppb	5	4	ND - 1.80 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
2014-03-10	B14030683-001A	ND
2014-06-10	B14061144-001A	ND
2014-09-17	B14091869-001F	ND
2014-09-17	B14091857-001A	ND
2014-12-09	B14120867-001A	ND
2015-02-17	B15021420-002A	ND
2015-06-03	B15060624-001A	ND
2015-09-23	B15092188-001C	ND
2015-09-28	B15092430-001A	ND
2016-01-28	B16011916-001A	0.820 ppb
2016-04-28	B16042326-001A	0.770 ppb
2016-08-28	B16082823-001A	ND
2017-01-11	B17010693-001A	ND
2017-12-04	B17120511-001B	ND
2017-12-04	B17120507-001A	0.500 ppb
2018-03-12	B18030871-002A	0.580 ppb
2018-03-12	B18030871-001A	0.520 ppb
2018-06-04	B18060309-001A	ND
2018-09-10	H18090183-004C	ND
2018-09-10	B18090855-001A	ND
2018-12-04	B18120338-001A	1.60 ppb
2019-03-04	B19030279-001C	1.70 ppb
2019-03-04	B19030188-001A	1.80 ppb
2019-06-03	B19060220-001A	0.960 ppb
2019-09-09	B19090729-001A	ND
2019-12-09	B19120805-001A	0.680 ppb