Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Haloacetic acids (HAA5)

City of Santa Clara

Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of five haloacetic acids regulated by federal standards includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid. Read More.

Haloacetic acids are harmful during pregnancy and may increase the risk of cancer. Haloacetic acids are� genotoxic, which means that they induce mutations and DNA damage. Multiple studies by the National Toxicology Program have demonstrated the cancer-causing properties of individual haloacetic acids in laboratory animals. The Department of Health and Human Services is currently considering listing di- or tri-haloacetic acids for possible inclusion in its comprehensive Report on Carcinogens.

Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

 

208

Samples

0

Samples exceeding legal limit (MCL)

164

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
201412.5 ppb3224ND - 30.0 ppb
201513.1 ppb3223ND - 31.0 ppb
201624.3 ppb4033ND - 52.0 ppb
201718.2 ppb3227ND - 48.0 ppb
201817.6 ppb4034ND - 56.0 ppb
201915.0 ppb3223ND - 47.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.1 ppb

The EWG Health Guideline of 0.1 ppb for the group of five haloacetic acids, or HAA5, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level. This health guideline protects against cancer.

EPA Maximum Contaminant
Level (MCL) 60 ppb

The legal limit for the group of five haloacetic acids (HAA5), established in 1998, was based on the need for residual disinfectant levels in water served to customers and the cost of treatment. This limit does not fully protect against the risk of cancer and harm to the developing fetus due to exposure to haloacetic acids.

ppb = parts per billion

All test results

Date Lab ID Result
2014-01-229590-900-104417.0 ppb
2014-01-229590-901-103010.00 ppb
2014-01-229590-902-110516.0 ppb
2014-01-229590-903-1015ND
2014-01-229590-904-0935ND
2014-01-229590-905-08345.00 ppb
2014-01-229590-906-085412.0 ppb
2014-01-229590-907-09556.90 ppb
2014-04-239590-900-102523.0 ppb
2014-04-239590-901-101028.0 ppb
2014-04-239590-902-104024.0 ppb
2014-04-239590-903-09555.40 ppb
2014-04-239590-904-0910ND
2014-04-239590-905-083529.0 ppb
2014-04-239590-906-085024.0 ppb
2014-04-239590-907-0930ND
2014-07-239590-900-134022.0 ppb
2014-07-239590-901-0905ND
2014-07-239590-902-094526.0 ppb
2014-07-239590-903-0845ND
2014-07-239590-904-1005ND
2014-07-239590-905-1025ND
2014-07-239590-906-104510.00 ppb
2014-07-239590-907-113011.0 ppb
2014-10-249590-900-091029.0 ppb
2014-10-249590-901-093030.0 ppb
2014-10-249590-902-085528.0 ppb
2014-10-249590-903-09155.40 ppb
2014-10-249590-904-10256.10 ppb
2014-10-249590-905-093512.0 ppb
2014-10-249590-906-095511.0 ppb
2014-10-249590-907-10459.70 ppb
2015-01-219590-900-121524.0 ppb
2015-01-219590-901-114223.0 ppb
2015-01-219590-902-112624.0 ppb
2015-01-219590-903-1150ND
2015-01-219590-904-0948ND
2015-01-219590-905-1003ND
2015-01-219590-906-102628.0 ppb
2015-01-219590-907-092614.0 ppb
2015-04-229590-900-094522.0 ppb
2015-04-229590-901-091525.0 ppb
2015-04-229590-902-101022.0 ppb
2015-04-229590-903-0858ND
2015-04-229590-904-11255.10 ppb
2015-04-229590-905-1410ND
2015-04-229590-906-143522.0 ppb
2015-04-229590-907-1140ND
2015-07-239590-900-141023.0 ppb
2015-07-239590-901-11157.10 ppb
2015-07-239590-902-134524.0 ppb
2015-07-239590-903-1050ND
2015-07-239590-904-095016.0 ppb
2015-07-239590-905-085016.0 ppb
2015-07-239590-906-091016.0 ppb
2015-07-239590-907-10158.70 ppb
2015-10-219590-900-132131.0 ppb
2015-10-219590-901-11259.20 ppb
2015-10-219590-902-134030.0 ppb
2015-10-219590-903-1108ND
2015-10-219590-904-10229.20 ppb
2015-10-219590-905-0923ND
2015-10-219590-906-095710.00 ppb
2015-10-219590-907-10419.70 ppb
2016-01-209590-900-100046.0 ppb
2016-01-209590-901-093534.0 ppb
2016-01-209590-902-102044.0 ppb
2016-01-209590-903-09152.80 ppb
2016-01-209590-904-13569.60 ppb
2016-01-209590-905-104518.0 ppb
2016-01-209590-906-110225.0 ppb
2016-01-209590-907-141322.0 ppb
2016-01-279590-900-112749.0 ppb
2016-01-279590-901-110549.0 ppb
2016-01-279590-902-114652.0 ppb
2016-01-279590-903-105048.0 ppb
2016-01-279590-904-1206ND
2016-01-279590-905-1218ND
2016-01-279590-906-123218.0 ppb
2016-01-279590-907-135618.0 ppb
2016-04-209590-900-102144.0 ppb
2016-04-209590-901-100233.0 ppb
2016-04-209590-902-104340.0 ppb
2016-04-209590-903-0942ND
2016-04-209590-904-1159ND
2016-04-209590-905-1106ND
2016-04-209590-906-112933.0 ppb
2016-04-209590-907-122429.0 ppb
2016-07-209590-900-110345.0 ppb
2016-07-209590-901-082744.0 ppb
2016-07-209590-902-085545.0 ppb
2016-07-209590-903-080915.0 ppb
2016-07-209590-904-100712.0 ppb
2016-07-209590-905-092517.0 ppb
2016-07-209590-906-094218.0 ppb
2016-07-209590-907-1022ND
2016-10-269590-900-092739.0 ppb
2016-10-269590-901-091445.0 ppb
2016-10-269590-902-094041.0 ppb
2016-10-269590-903-0901ND
2016-10-269590-904-105512.0 ppb
2016-10-269590-905-10032.40 ppb
2016-10-269590-906-102110.00 ppb
2016-10-269590-907-110811.0 ppb
2017-01-259590-900-11288.10 ppb
2017-01-259590-901-12019.80 ppb
2017-01-259590-902-10548.20 ppb
2017-01-259590-903-11468.60 ppb
2017-01-259590-904-0959ND
2017-01-259590-905-08525.00 ppb
2017-01-259590-906-091511.0 ppb
2017-01-259590-907-10286.90 ppb
2017-04-199590-900-120042.0 ppb
2017-04-199590-901-104845.0 ppb
2017-04-199590-902-121942.0 ppb
2017-04-199590-903-103548.0 ppb
2017-04-199590-904-0952ND
2017-04-199590-905-0838ND
2017-04-199590-906-090312.0 ppb
2017-04-199590-907-101013.0 ppb
2017-08-029590-900-105338.0 ppb
2017-08-029590-901-103840.0 ppb
2017-08-029590-902-111840.0 ppb
2017-08-029590-903-1025ND
2017-08-029590-904-093813.0 ppb
2017-08-029590-905-084116.0 ppb
2017-08-029590-906-090112.0 ppb
2017-08-029590-907-0953ND
2017-10-189590-900-101429.0 ppb
2017-10-189590-901-092930.0 ppb
2017-10-189590-902-095928.0 ppb
2017-10-189590-903-091425.0 ppb
2017-10-189590-904-114414.0 ppb
2017-10-189590-905-115515.0 ppb
2017-10-189590-906-125314.0 ppb
2017-10-189590-907-12128.30 ppb
2018-01-299590-900-075524.0 ppb
2018-01-299590-901-084324.0 ppb
2018-01-299590-902-081727.0 ppb
2018-01-299590-903-083213.0 ppb
2018-01-299590-904-1008ND
2018-01-299590-905-09094.10 ppb
2018-01-299590-906-09289.50 ppb
2018-01-299590-907-10239.40 ppb
2018-04-179590-900-094256.0 ppb
2018-04-179590-901-092444.0 ppb
2018-04-179590-902-101410.00 ppb
2018-04-179590-903-091017.0 ppb
2018-04-179590-904-10342.60 ppb
2018-04-179590-905-1048ND
2018-04-179590-906-110723.0 ppb
2018-04-179590-907-113525.0 ppb
2018-04-269590-900-094043.0 ppb
2018-04-269590-901-084942.0 ppb
2018-04-269590-902-100312.0 ppb
2018-04-269590-903-08354.50 ppb
2018-04-269590-904-11016.30 ppb
2018-04-269590-905-1026ND
2018-04-269590-906-104213.0 ppb
2018-04-269590-907-1115ND
2018-07-259590-900-090037.0 ppb
2018-07-259590-901-084838.0 ppb
2018-07-259590-902-09153.50 ppb
2018-07-259590-903-083839.0 ppb
2018-07-259590-904-101512.0 ppb
2018-07-259590-905-0939ND
2018-07-259590-906-095412.0 ppb
2018-07-259590-907-102710.00 ppb
2018-10-179590-900-093030.0 ppb
2018-10-179590-901-090429.0 ppb
2018-10-179590-902-094633.0 ppb
2018-10-179590-903-085018.0 ppb
2018-10-179590-904-10079.40 ppb
2018-10-179590-905-101911.0 ppb
2018-10-179590-906-105411.0 ppb
2018-10-179590-907-1117ND
2019-01-169590-900-09579.20 ppb
2019-01-169590-901-09348.80 ppb
2019-01-169590-902-1016ND
2019-01-169590-903-09248.70 ppb
2019-01-169590-904-07419.80 ppb
2019-01-169590-905-075316.0 ppb
2019-01-169590-906-080915.0 ppb
2019-01-169590-907-0852ND
2019-04-179590-900-093429.0 ppb
2019-04-179590-901-091831.0 ppb
2019-04-179590-902-09493.50 ppb
2019-04-179590-903-090631.0 ppb
2019-04-179590-904-1012ND
2019-04-179590-905-1028ND
2019-04-179590-906-105514.0 ppb
2019-04-179590-907-111914.0 ppb
2019-07-159590-900-111638.0 ppb
2019-07-159590-901-105647.0 ppb
2019-07-159590-902-112941.0 ppb
2019-07-159590-903-1040ND
2019-07-159590-904-094911.0 ppb
2019-07-159590-905-100911.0 ppb
2019-07-159590-906-092611.0 ppb
2019-07-159590-907-0843ND
2019-10-159590-900-081432.0 ppb
2019-10-159590-901-075839.0 ppb
2019-10-159590-902-083432.0 ppb
2019-10-159590-903-0745ND
2019-10-159590-904-10179.60 ppb
2019-10-159590-905-0941ND
2019-10-159590-906-095819.0 ppb
2019-10-159590-907-1028ND