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EWG's Tap Water Database — 2021 UPDATE

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Dichloroacetic acid

City of San Marcos

Dichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids 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)

174

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20145.75 ppb3231ND - 12.1 ppb
20157.11 ppb3231ND - 13.0 ppb
20167.98 ppb3225ND - 25.1 ppb
20173.69 ppb3229ND - 5.70 ppb
20184.34 ppb3230ND - 11.7 ppb
20193.95 ppb3228ND - 7.40 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.2 ppb

The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.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
2014-03-12AC467522.70 ppb
2014-03-12AC467473.90 ppb
2014-03-12AC467592.80 ppb
2014-03-12AC467582.70 ppb
2014-03-12AC46734ND
2014-03-12AC467462.30 ppb
2014-03-12AC467383.20 ppb
2014-03-12AC467373.00 ppb
2014-06-26AC583147.20 ppb
2014-06-26AC582994.50 ppb
2014-06-26AC583127.50 ppb
2014-06-26AC583176.00 ppb
2014-06-26AC583167.10 ppb
2014-06-26AC583185.40 ppb
2014-06-26AC583205.50 ppb
2014-06-26AC583156.00 ppb
2014-08-12AC632356.70 ppb
2014-08-12AC632364.80 ppb
2014-08-12AC632537.20 ppb
2014-08-12AC632408.80 ppb
2014-08-12AC632388.30 ppb
2014-08-12AC632475.10 ppb
2014-08-12AC632377.10 ppb
2014-09-25AC6832012.1 ppb
2014-10-29AC708896.50 ppb
2014-10-29AC708837.00 ppb
2014-10-29AC708867.20 ppb
2014-10-29AC708726.80 ppb
2014-10-29AC708818.30 ppb
2014-10-29AC708884.50 ppb
2014-10-29AC708826.80 ppb
2014-10-29AC708757.00 ppb
2015-03-11AC837203.20 ppb
2015-03-11AC837222.90 ppb
2015-03-11AC837193.10 ppb
2015-03-11AC837253.70 ppb
2015-03-11AC837233.30 ppb
2015-03-11AC837272.30 ppb
2015-03-11AC837292.90 ppb
2015-03-11AC837283.10 ppb
2015-06-10AC9537011.1 ppb
2015-06-10AC9542711.5 ppb
2015-06-10AC9540312.3 ppb
2015-06-10AC9540013.0 ppb
2015-06-10AC9542211.6 ppb
2015-06-10AC954239.20 ppb
2015-06-10AC9540210.00 ppb
2015-06-10AC954017.30 ppb
2015-09-23AD0822210.4 ppb
2015-09-23AD082167.50 ppb
2015-09-23AD0822010.8 ppb
2015-09-23AD0821711.1 ppb
2015-09-23AD0822310.5 ppb
2015-09-23AD08218ND
2015-09-23AD0821910.2 ppb
2015-09-23AD0822110.3 ppb
2015-12-01AD149026.10 ppb
2015-12-01AD148755.00 ppb
2015-12-01AD148687.20 ppb
2015-12-01AD148767.30 ppb
2015-12-01AD148749.20 ppb
2015-12-01AD149004.90 ppb
2015-12-01AD148785.50 ppb
2015-12-01AD148691.000 ppb
2016-03-16AD2904313.1 ppb
2016-03-16AD2904110.6 ppb
2016-03-16AD2904910.1 ppb
2016-03-16AD2904210.00 ppb
2016-03-16AD2904817.0 ppb
2016-03-16AD2904411.5 ppb
2016-03-16AD2904511.4 ppb
2016-03-16AD290466.50 ppb
2016-06-16AD409491.000 ppb
2016-06-16AD4095425.1 ppb
2016-06-16AD409455.30 ppb
2016-06-16AD4095817.6 ppb
2016-06-16AD40951ND
2016-06-16AD4095322.8 ppb
2016-06-16AD40948ND
2016-06-28AD4211022.2 ppb
2016-09-16AD49834ND
2016-09-16AD498369.80 ppb
2016-09-16AD498331.50 ppb
2016-09-16AD49830ND
2016-09-16AD498319.10 ppb
2016-09-16AD498358.70 ppb
2016-09-16AD498327.80 ppb
2016-09-16AD49837ND
2016-11-28AD591884.60 ppb
2016-11-28AD591874.60 ppb
2016-11-28AD591894.80 ppb
2016-11-28AD591904.40 ppb
2016-11-28AD591855.60 ppb
2016-11-28AD59191ND
2016-11-28AD5918610.2 ppb
2016-11-28AD59192ND
2017-02-22AD714874.00 ppb
2017-02-22AD71490ND
2017-02-22AD714843.60 ppb
2017-02-22AD714925.40 ppb
2017-02-22AD714854.50 ppb
2017-02-22AD71488ND
2017-02-22AD714913.20 ppb
2017-02-22AD71486ND
2017-05-03AD824204.20 ppb
2017-05-03AD824334.50 ppb
2017-05-03AD824314.00 ppb
2017-05-03AD824295.10 ppb
2017-05-03AD824264.50 ppb
2017-05-03AD824182.80 ppb
2017-05-03AD824193.60 ppb
2017-05-03AD824173.10 ppb
2017-07-12AD890663.30 ppb
2017-07-12AD890683.30 ppb
2017-07-12AD890703.40 ppb
2017-07-12AD890645.70 ppb
2017-07-12AD890694.40 ppb
2017-07-12AD890673.50 ppb
2017-07-12AD890653.90 ppb
2017-07-12AD890712.40 ppb
2017-10-12AE005403.80 ppb
2017-10-12AE005443.90 ppb
2017-10-12AE005464.50 ppb
2017-10-12AE005425.30 ppb
2017-10-12AE005415.50 ppb
2017-10-12AE005454.60 ppb
2017-10-12AE005433.40 ppb
2017-10-12AE005394.70 ppb
2018-01-25AE104682.40 ppb
2018-01-25AE104692.30 ppb
2018-01-25AE104702.60 ppb
2018-01-25AE104651.30 ppb
2018-01-25AE104712.70 ppb
2018-01-25AE104672.10 ppb
2018-01-25AE104662.50 ppb
2018-01-25AE10472ND
2018-04-11AE219934.30 ppb
2018-04-11AE219944.40 ppb
2018-04-11AE219963.10 ppb
2018-04-11AE219976.40 ppb
2018-04-11AE219987.40 ppb
2018-04-11AE219992.70 ppb
2018-04-11AE219924.00 ppb
2018-04-11AE21995ND
2018-07-26AE346429.30 ppb
2018-07-26AE346407.00 ppb
2018-07-26AE346476.50 ppb
2018-07-26AE346488.70 ppb
2018-07-26AE346468.40 ppb
2018-07-26AE346435.70 ppb
2018-07-26AE3464111.7 ppb
2018-07-26AE346492.20 ppb
2018-10-17AE437573.10 ppb
2018-10-17AE437525.10 ppb
2018-10-17AE437543.30 ppb
2018-10-17AE437535.70 ppb
2018-10-17AE437585.20 ppb
2018-10-17AE437552.60 ppb
2018-10-17AE437513.10 ppb
2018-10-17AE437563.10 ppb
2019-01-16AE500626.00 ppb
2019-01-16AE500646.20 ppb
2019-01-16AE500606.10 ppb
2019-01-16AE500597.40 ppb
2019-01-16AE500657.20 ppb
2019-01-16AE500665.20 ppb
2019-01-16AE500635.70 ppb
2019-01-16AE500615.20 ppb
2019-04-16AE625235.20 ppb
2019-04-16AE625254.50 ppb
2019-04-16AE625133.30 ppb
2019-04-16AE625064.90 ppb
2019-04-16AE625244.20 ppb
2019-04-16AE625073.40 ppb
2019-04-16AE625203.10 ppb
2019-04-16AE625023.80 ppb
2019-07-09AE736444.00 ppb
2019-07-09AE736416.80 ppb
2019-07-09AE736424.50 ppb
2019-07-09AE736465.00 ppb
2019-07-09AE73643ND
2019-07-09AE736474.10 ppb
2019-07-09AE73653ND
2019-07-09AE736485.30 ppb
2019-10-10AE862912.70 ppb
2019-10-10AE862992.20 ppb
2019-10-10AE862943.00 ppb
2019-10-10AE862932.50 ppb
2019-10-10AE86298ND
2019-10-10AE862952.40 ppb
2019-10-10AE86292ND
2019-10-10AE862972.40 ppb