Bromoform

City of Hollister

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

121

Samples

Samples exceeding legal limit (MCL)

119

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	15.7 ppb	16	16	3.62 ppb - 44.7 ppb
2015	36.4 ppb	16	16	13.1 ppb - 73.7 ppb
2016	22.4 ppb	21	21	6.54 ppb - 68.0 ppb
2017	28.7 ppb	16	16	8.30 ppb - 105.1 ppb
2018	24.9 ppb	20	19	ND - 51.1 ppb
2019	27.2 ppb	32	31	ND - 92.4 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
2014-03-24	1610-801-1710	44.7 ppb
2014-03-24	1610-802-1615	8.99 ppb
2014-03-24	1610-803-1555	16.9 ppb
2014-03-24	1610-804-1650	19.8 ppb
2014-06-06	1610-801-1445	18.4 ppb
2014-06-06	1610-802-1520	29.4 ppb
2014-06-06	1610-803-1540	6.85 ppb
2014-06-06	1610-804-1458	7.79 ppb
2014-10-09	1610-801-1150	14.9 ppb
2014-10-09	1610-802-1100	6.00 ppb
2014-10-09	1610-803-1130	5.81 ppb
2014-10-09	1610-804-1205	24.7 ppb
2014-12-18	1610-801-1235	25.7 ppb
2014-12-18	1610-802-1255	3.62 ppb
2014-12-18	1610-803-1310	4.01 ppb
2014-12-18	1610-804-1220	14.2 ppb
2015-04-21	1610-801-1350	50.4 ppb
2015-04-21	1610-802-1321	13.6 ppb
2015-04-21	1610-803-1328	13.1 ppb
2015-04-21	1610-804-1341	67.4 ppb
2015-07-09	1610-801-1008	66.8 ppb
2015-07-09	1610-802-0843	26.6 ppb
2015-07-09	1610-803-0903	21.5 ppb
2015-07-09	1610-804-0954	73.7 ppb
2015-09-16	1610-801-1440	25.7 ppb
2015-09-16	1610-802-1344	13.9 ppb
2015-09-16	1610-803-1359	13.6 ppb
2015-09-16	1610-804-1422	36.8 ppb
2015-11-12	1610-801-0840	56.7 ppb
2015-11-12	1610-802-0920	19.2 ppb
2015-11-12	1610-803-0932	20.7 ppb
2015-11-12	1610-804-0858	63.0 ppb
2016-03-03	1610-801-0913	68.0 ppb
2016-03-03	1610-802-0817	25.4 ppb
2016-03-03	1610-803-0829	29.7 ppb
2016-03-03	1610-804-0856	59.8 ppb
2016-06-14	1610-801-1442	22.9 ppb
2016-06-14	1610-802-1428	18.5 ppb
2016-06-14	1610-803-1421	27.2 ppb
2016-06-14	1610-804-1523	28.7 ppb
2016-06-29	1610-804-1123	13.3 ppb
2016-07-07	1610-804-1237	19.2 ppb
2016-07-14	1610-804-1245	14.8 ppb
2016-07-21	1610-804-1015	18.4 ppb
2016-08-04	1610-804-1320	14.8 ppb
2016-09-22	1610-801-1155	14.4 ppb
2016-09-22	1610-802-1110	8.11 ppb
2016-09-22	1610-803-1100	6.54 ppb
2016-09-22	1610-804-1205	17.3 ppb
2016-12-14	1610-801-1309	26.3 ppb
2016-12-14	1610-802-1251	11.6 ppb
2016-12-14	1610-803-1237	13.3 ppb
2016-12-14	1610-804-1316	13.2 ppb
2017-03-01	1610-801-1150	22.6 ppb
2017-03-01	1610-802-1202	8.30 ppb
2017-03-01	1610-803-1209	8.94 ppb
2017-03-01	1610-804-1141	18.2 ppb
2017-06-01	1610-801-1245	20.2 ppb
2017-06-01	1610-802-1159	15.4 ppb
2017-06-01	1610-803-1210	18.3 ppb
2017-06-01	1610-804-1226	21.2 ppb
2017-09-07	1610-801-1148	18.3 ppb
2017-09-07	1610-802-1202	105.1 ppb
2017-09-07	1610-803-1208	15.8 ppb
2017-09-07	1610-804-1142	22.6 ppb
2017-12-07	1610-801-0914	35.2 ppb
2017-12-07	1610-802-0934	38.5 ppb
2017-12-07	1610-803-0926	40.1 ppb
2017-12-07	1610-804-0905	50.0 ppb
2018-03-08	1610-801-1148	21.2 ppb
2018-03-08	1610-802-1109	6.27 ppb
2018-03-08	1610-803-1120	8.08 ppb
2018-03-08	1610-804-1136	23.3 ppb
2018-06-07	1610-801-0937	42.5 ppb
2018-06-07	1610-802-0910	19.1 ppb
2018-06-07	1610-803-0900	19.3 ppb
2018-06-07	1610-804-0925	51.1 ppb
2018-09-06	1610-801-1108	41.3 ppb
2018-09-06	1610-802-1045	22.3 ppb
2018-09-06	1610-803-1050	23.3 ppb
2018-09-06	1610-804-1105	50.0 ppb
2018-12-06	1610-801-1224	42.7 ppb
2018-12-06	1610-802-1145	17.1 ppb
2018-12-06	1610-803-1135	21.7 ppb
2018-12-06	1610-804-1243	26.8 ppb
2018-12-06	1610-805-1311	23.1 ppb
2018-12-06	1610-806-1117	20.4 ppb
2018-12-06	1610-808-1031	19.1 ppb
2018-12-06	1610-809-1040	ND
2019-03-14	1610-801-1025	31.5 ppb
2019-03-14	1610-802-1040	34.6 ppb
2019-03-14	1610-803-1050	33.7 ppb
2019-03-14	1610-804-1010	28.2 ppb
2019-03-14	1610-805-1115	22.7 ppb
2019-03-14	1610-806-1100	31.2 ppb
2019-03-14	1610-808-1130	29.9 ppb
2019-03-14	1610-809-1150	ND
2019-06-06	1610-801-0945	28.0 ppb
2019-06-06	1610-802-0923	25.7 ppb
2019-06-06	1610-803-0914	25.2 ppb
2019-06-06	1610-804-0936	28.6 ppb
2019-06-06	1610-805-0850	7.14 ppb
2019-06-06	1610-806-0904	30.2 ppb
2019-06-06	1610-808-0829	20.6 ppb
2019-06-06	1610-810-0820	16.9 ppb
2019-09-10	1610-801-1017	92.4 ppb
2019-09-10	1610-802-1006	23.1 ppb
2019-09-10	1610-803-1000	35.8 ppb
2019-09-10	1610-804-1025	59.0 ppb
2019-09-10	1610-805-1046	9.88 ppb
2019-09-10	1610-806-1109	30.2 ppb
2019-09-10	1610-808-1130	38.7 ppb
2019-09-10	1610-810-1124	34.2 ppb
2019-12-05	1610-801-1051	20.4 ppb
2019-12-05	1610-802-1125	23.3 ppb
2019-12-05	1610-803-1135	17.6 ppb
2019-12-05	1610-804-1109	30.2 ppb
2019-12-05	1610-805-1203	11.3 ppb
2019-12-05	1610-806-1010	22.4 ppb
2019-12-05	1610-808-0939	13.5 ppb
2019-12-05	1610-810-0925	16.0 ppb