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EWG's Tap Water Database — 2021 UPDATE

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Monochloroacetic acid

City of San Marcos

Monochloroacetic 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)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.244 ppb323ND - 3.00 ppb
20150.128 ppb321ND - 4.10 ppb
20162.84 ppb3217ND - 16.3 ppb
20170.213 ppb323ND - 2.60 ppb
20180.0688 ppb321ND - 2.20 ppb
20190.509 ppb326ND - 4.10 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 53 ppb

The EWG Health Guideline of 53 ppb for monochloroacetic 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.. This health guideline protects against system toxicity.

ppb = parts per billion

All test results

Date Lab ID Result
2014-03-12AC46752ND
2014-03-12AC46747ND
2014-03-12AC46759ND
2014-03-12AC46758ND
2014-03-12AC46734ND
2014-03-12AC46746ND
2014-03-12AC46738ND
2014-03-12AC46737ND
2014-06-26AC58314ND
2014-06-26AC58299ND
2014-06-26AC58312ND
2014-06-26AC58317ND
2014-06-26AC58316ND
2014-06-26AC58318ND
2014-06-26AC58320ND
2014-06-26AC58315ND
2014-08-12AC63235ND
2014-08-12AC63236ND
2014-08-12AC632532.40 ppb
2014-08-12AC63240ND
2014-08-12AC63238ND
2014-08-12AC63247ND
2014-08-12AC63237ND
2014-09-25AC683203.00 ppb
2014-10-29AC70889ND
2014-10-29AC70883ND
2014-10-29AC70886ND
2014-10-29AC70872ND
2014-10-29AC70881ND
2014-10-29AC708882.40 ppb
2014-10-29AC70882ND
2014-10-29AC70875ND
2015-03-11AC83720ND
2015-03-11AC83722ND
2015-03-11AC83719ND
2015-03-11AC83725ND
2015-03-11AC83723ND
2015-03-11AC83727ND
2015-03-11AC83729ND
2015-03-11AC83728ND
2015-06-10AC95370ND
2015-06-10AC95427ND
2015-06-10AC95403ND
2015-06-10AC95400ND
2015-06-10AC95422ND
2015-06-10AC95423ND
2015-06-10AC95402ND
2015-06-10AC95401ND
2015-09-23AD08222ND
2015-09-23AD08216ND
2015-09-23AD08220ND
2015-09-23AD08217ND
2015-09-23AD08223ND
2015-09-23AD08218ND
2015-09-23AD08219ND
2015-09-23AD08221ND
2015-12-01AD14902ND
2015-12-01AD14875ND
2015-12-01AD148684.10 ppb
2015-12-01AD14876ND
2015-12-01AD14874ND
2015-12-01AD14900ND
2015-12-01AD14878ND
2015-12-01AD14869ND
2016-03-16AD290433.50 ppb
2016-03-16AD290413.00 ppb
2016-03-16AD29049ND
2016-03-16AD290423.60 ppb
2016-03-16AD29048ND
2016-03-16AD290443.90 ppb
2016-03-16AD290453.20 ppb
2016-03-16AD290463.00 ppb
2016-06-16AD40949ND
2016-06-16AD4095414.6 ppb
2016-06-16AD40945ND
2016-06-16AD409587.10 ppb
2016-06-16AD40951ND
2016-06-16AD4095312.2 ppb
2016-06-16AD40948ND
2016-06-28AD4211016.3 ppb
2016-09-16AD49834ND
2016-09-16AD498364.80 ppb
2016-09-16AD49833ND
2016-09-16AD49830ND
2016-09-16AD498313.40 ppb
2016-09-16AD498352.50 ppb
2016-09-16AD498322.90 ppb
2016-09-16AD49837ND
2016-11-28AD591882.50 ppb
2016-11-28AD59187ND
2016-11-28AD591892.20 ppb
2016-11-28AD59190ND
2016-11-28AD591852.20 ppb
2016-11-28AD59191ND
2016-11-28AD59186ND
2016-11-28AD59192ND
2017-02-22AD71487ND
2017-02-22AD71490ND
2017-02-22AD71484ND
2017-02-22AD71492ND
2017-02-22AD71485ND
2017-02-22AD71488ND
2017-02-22AD71491ND
2017-02-22AD71486ND
2017-05-03AD824202.60 ppb
2017-05-03AD82433ND
2017-05-03AD82431ND
2017-05-03AD824292.10 ppb
2017-05-03AD82426ND
2017-05-03AD82418ND
2017-05-03AD824192.10 ppb
2017-05-03AD82417ND
2017-07-12AD89066ND
2017-07-12AD89068ND
2017-07-12AD89070ND
2017-07-12AD89064ND
2017-07-12AD89069ND
2017-07-12AD89067ND
2017-07-12AD89065ND
2017-07-12AD89071ND
2017-10-12AE00540ND
2017-10-12AE00544ND
2017-10-12AE00546ND
2017-10-12AE00542ND
2017-10-12AE00541ND
2017-10-12AE00545ND
2017-10-12AE00543ND
2017-10-12AE00539ND
2018-01-25AE10468ND
2018-01-25AE10469ND
2018-01-25AE10470ND
2018-01-25AE10465ND
2018-01-25AE10471ND
2018-01-25AE10467ND
2018-01-25AE10466ND
2018-01-25AE10472ND
2018-04-11AE21993ND
2018-04-11AE21994ND
2018-04-11AE21996ND
2018-04-11AE21997ND
2018-04-11AE21998ND
2018-04-11AE21999ND
2018-04-11AE219922.20 ppb
2018-04-11AE21995ND
2018-07-26AE34642ND
2018-07-26AE34640ND
2018-07-26AE34647ND
2018-07-26AE34648ND
2018-07-26AE34646ND
2018-07-26AE34643ND
2018-07-26AE34641ND
2018-07-26AE34649ND
2018-10-17AE43757ND
2018-10-17AE43752ND
2018-10-17AE43754ND
2018-10-17AE43753ND
2018-10-17AE43758ND
2018-10-17AE43755ND
2018-10-17AE43751ND
2018-10-17AE43756ND
2019-01-16AE500622.40 ppb
2019-01-16AE500642.40 ppb
2019-01-16AE500602.80 ppb
2019-01-16AE50059ND
2019-01-16AE500654.10 ppb
2019-01-16AE50066ND
2019-01-16AE500632.10 ppb
2019-01-16AE50061ND
2019-04-16AE62523ND
2019-04-16AE62525ND
2019-04-16AE62513ND
2019-04-16AE62506ND
2019-04-16AE62524ND
2019-04-16AE62507ND
2019-04-16AE62520ND
2019-04-16AE62502ND
2019-07-09AE73644ND
2019-07-09AE73641ND
2019-07-09AE73642ND
2019-07-09AE73646ND
2019-07-09AE73643ND
2019-07-09AE73647ND
2019-07-09AE73653ND
2019-07-09AE73648ND
2019-10-10AE86291ND
2019-10-10AE86299ND
2019-10-10AE862942.50 ppb
2019-10-10AE86293ND
2019-10-10AE86298ND
2019-10-10AE86295ND
2019-10-10AE86292ND
2019-10-10AE86297ND