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EWG's Tap Water Database — 2021 UPDATE

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Bromoform

California Water Service - San Mateo

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

 

192

Samples

0

Samples exceeding legal limit (MCL)

16

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.168 ppb324ND - 1.67 ppb
20150.112 ppb325ND - 0.920 ppb
2016ND320ND
2017ND320ND
20180.473 ppb327ND - 3.47 ppb
2019ND320ND

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
2014-02-055701-900-12050.990 ppb
2014-02-055701-901-1120ND
2014-02-055701-902-1105ND
2014-02-055701-903-09451.67 ppb
2014-02-055701-904-1140ND
2014-02-055701-905-10001.65 ppb
2014-02-055701-906-1020ND
2014-02-055701-907-12251.08 ppb
2014-05-075701-900-1515ND
2014-05-075701-901-1545ND
2014-05-075701-902-1600ND
2014-05-075701-903-1540ND
2014-05-075701-904-1705ND
2014-05-075701-905-1600ND
2014-05-075701-906-1434ND
2014-05-075701-907-1455ND
2014-08-065701-900-1300ND
2014-08-065701-901-1100ND
2014-08-065701-902-1115ND
2014-08-065701-903-1250ND
2014-08-065701-904-1025ND
2014-08-065701-905-1305ND
2014-08-065701-906-1140ND
2014-08-065701-907-1355ND
2014-11-035701-900-1300ND
2014-11-035701-901-1245ND
2014-11-035701-902-1230ND
2014-11-035701-903-1150ND
2014-11-035701-904-1350ND
2014-11-035701-905-1125ND
2014-11-035701-906-1335ND
2014-11-035701-907-1320ND
2015-02-045701-900-08500.560 ppb
2015-02-045701-901-08500.670 ppb
2015-02-045701-902-08500.740 ppb
2015-02-045701-903-0850ND
2015-02-045701-904-08500.920 ppb
2015-02-045701-905-0850ND
2015-02-045701-906-08500.680 ppb
2015-02-045701-907-0850ND
2015-05-065701-900-0832ND
2015-05-065701-901-0832ND
2015-05-065701-902-0832ND
2015-05-065701-903-0832ND
2015-05-065701-904-0832ND
2015-05-065701-905-0832ND
2015-05-065701-906-0832ND
2015-05-065701-907-0832ND
2015-08-045701-900-0827ND
2015-08-045701-901-0827ND
2015-08-045701-902-0827ND
2015-08-045701-903-0827ND
2015-08-045701-904-0827ND
2015-08-045701-905-0827ND
2015-08-045701-906-0827ND
2015-08-045701-907-0827ND
2015-11-035701-900-0818ND
2015-11-035701-901-0818ND
2015-11-035701-902-0818ND
2015-11-035701-903-0818ND
2015-11-035701-904-0818ND
2015-11-035701-905-0818ND
2015-11-035701-906-0818ND
2015-12-095810-907-0840ND
2016-02-025701-900-0858ND
2016-02-025701-901-0858ND
2016-02-025701-902-0858ND
2016-02-025701-903-0858ND
2016-02-025701-904-0858ND
2016-02-025701-905-0858ND
2016-02-025701-906-0858ND
2016-02-025701-907-0858ND
2016-05-025701-900-0714ND
2016-05-025701-901-0714ND
2016-05-025701-902-0714ND
2016-05-025701-903-0714ND
2016-05-025701-904-0714ND
2016-05-025701-905-0714ND
2016-05-025701-906-0714ND
2016-05-025701-907-0714ND
2016-08-025701-900-0856ND
2016-08-025701-901-0856ND
2016-08-025701-902-0856ND
2016-08-025701-903-0856ND
2016-08-025701-904-0856ND
2016-08-025701-905-0856ND
2016-08-025701-906-0856ND
2016-08-025701-907-0856ND
2016-11-075701-900-0931ND
2016-11-075701-901-0931ND
2016-11-075701-902-0931ND
2016-11-075701-903-0931ND
2016-11-075701-904-0931ND
2016-11-075701-905-0931ND
2016-11-075701-906-0931ND
2016-11-095701-907-0844ND
2017-02-065701-900-0653ND
2017-02-065701-901-0653ND
2017-02-065701-902-0653ND
2017-02-065701-903-0653ND
2017-02-065701-904-0654ND
2017-02-065701-905-0654ND
2017-02-065701-906-0654ND
2017-02-065701-907-0654ND
2017-05-015810-900-1510ND
2017-05-015810-901-1100ND
2017-05-015810-902-1145ND
2017-05-015810-903-1440ND
2017-05-015810-904-1115ND
2017-05-015810-905-1455ND
2017-05-015810-906-1030ND
2017-05-015810-907-1045ND
2017-08-095810-900-0820ND
2017-08-095810-901-1140ND
2017-08-095810-902-1150ND
2017-08-095810-903-1315ND
2017-08-095810-904-0740ND
2017-08-095810-905-1300ND
2017-08-095810-906-1205ND
2017-08-095810-907-0900ND
2017-11-085701-900-0904ND
2017-11-085701-901-0904ND
2017-11-085701-902-0904ND
2017-11-085701-903-0904ND
2017-11-085701-904-0904ND
2017-11-085701-905-0904ND
2017-11-085701-906-0904ND
2017-11-085701-907-0904ND
2018-02-055810-900-1250ND
2018-02-055810-901-1220ND
2018-02-055810-902-1205ND
2018-02-055810-903-1020ND
2018-02-055810-904-1235ND
2018-02-055810-905-1315ND
2018-02-055810-906-0935ND
2018-02-055810-907-0955ND
2018-05-075701-900-0852ND
2018-05-075701-901-0852ND
2018-05-075701-902-0852ND
2018-05-075701-903-0852ND
2018-05-075701-904-0852ND
2018-05-075701-905-0852ND
2018-05-075701-906-0852ND
2018-05-075701-907-0852ND
2018-08-065701-900-0809ND
2018-08-065701-901-0809ND
2018-08-065701-902-0809ND
2018-08-065701-903-0809ND
2018-08-065701-904-0809ND
2018-08-065701-905-0809ND
2018-08-065701-906-0809ND
2018-08-065701-907-0809ND
2018-11-055701-900-1021ND
2018-11-055701-901-10212.78 ppb
2018-11-055701-902-10212.47 ppb
2018-11-055701-903-10210.860 ppb
2018-11-055701-904-10213.47 ppb
2018-11-055701-905-10211.31 ppb
2018-11-055701-906-10213.39 ppb
2018-11-055701-907-10210.840 ppb
2019-02-065701-900-0623ND
2019-02-065701-901-0623ND
2019-02-065701-902-0623ND
2019-02-065701-903-0623ND
2019-02-065701-904-0623ND
2019-02-065701-905-0623ND
2019-02-065701-906-0623ND
2019-02-065701-907-0623ND
2019-05-075701-900-0858ND
2019-05-075701-901-0858ND
2019-05-075701-902-0858ND
2019-05-075701-903-0858ND
2019-05-075701-904-0858ND
2019-05-075701-905-0858ND
2019-05-075701-906-0858ND
2019-05-075701-907-0858ND
2019-08-065701-900-0820ND
2019-08-065701-901-1000ND
2019-08-065701-902-1010ND
2019-08-065701-903-0745ND
2019-08-065701-904-0940ND
2019-08-065701-905-0800ND
2019-08-065701-906-1030ND
2019-08-065701-907-0835ND
2019-11-055701-900-1145ND
2019-11-055701-901-0915ND
2019-11-055701-902-0925ND
2019-11-055701-903-1125ND
2019-11-055701-904-0855ND
2019-11-055701-905-1130ND
2019-11-055701-906-1215ND
2019-11-055701-907-1200ND