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EWG's Tap Water Database — 2021 UPDATE

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Haloacetic acids (HAA5)

Atascosa Rural WSC

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

 

96

Samples

0

Samples exceeding legal limit (MCL)

24

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.300 ppb164ND - 1.50 ppb
20150.138 ppb162ND - 1.20 ppb
20160.588 ppb164ND - 4.90 ppb
20170.806 ppb166ND - 3.70 ppb
20180.275 ppb164ND - 1.20 ppb
20190.400 ppb164ND - 2.10 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
2014-02-12AC42464ND
2014-02-12AC42465ND
2014-02-12AC42452ND
2014-02-12AC42455ND
2014-04-16AC50805ND
2014-04-16AC50804ND
2014-04-16AC50806ND
2014-04-16AC50803ND
2014-07-21AC603651.30 ppb
2014-07-21AC60364ND
2014-07-21AC60363ND
2014-07-21AC603621.000 ppb
2014-10-15AC69775ND
2014-10-15AC69773ND
2014-10-15AC697821.000 ppb
2014-10-15AC697741.50 ppb
2015-02-05AC79430ND
2015-02-05AC79459ND
2015-02-05AC79431ND
2015-02-05AC79427ND
2015-06-02AC94281ND
2015-06-02AC94279ND
2015-06-02AC94270ND
2015-06-02AC94282ND
2015-08-10AD03206ND
2015-08-10AD032071.000 ppb
2015-08-10AD03209ND
2015-08-10AD03200ND
2015-10-06AD09595ND
2015-10-06AD09577ND
2015-10-06AD095971.20 ppb
2015-10-06AD09594ND
2016-02-16AD236041.10 ppb
2016-02-16AD23605ND
2016-02-16AD23606ND
2016-02-16AD23602ND
2016-04-26AD34171ND
2016-04-26AD34170ND
2016-04-26AD34168ND
2016-04-26AD341524.90 ppb
2016-07-13AD44008ND
2016-07-13AD440031.000 ppb
2016-07-13AD44023ND
2016-07-13AD44024ND
2016-10-10AD52808ND
2016-10-10AD52804ND
2016-10-10AD52811ND
2016-10-10AD528092.40 ppb
2017-01-12AD64699ND
2017-01-12AD64700ND
2017-01-12AD64703ND
2017-01-12AD64724ND
2017-04-06AD78721ND
2017-04-06AD78720ND
2017-04-06AD787191.50 ppb
2017-04-06AD78718ND
2017-07-18AD89939ND
2017-07-18AD89944ND
2017-07-18AD89940ND
2017-07-18AD899351.10 ppb
2017-10-06AD997523.20 ppb
2017-10-06AD997532.30 ppb
2017-10-06AD997511.10 ppb
2017-10-06AD997543.70 ppb
2018-01-18AE092151.10 ppb
2018-01-18AE092101.20 ppb
2018-01-18AE09221ND
2018-01-18AE09229ND
2018-04-06AE216801.10 ppb
2018-04-06AE21679ND
2018-04-06AE21677ND
2018-04-06AE216781.000 ppb
2018-08-01AE35275ND
2018-08-01AE35276ND
2018-08-01AE35274ND
2018-08-01AE35273ND
2018-10-04AE42678ND
2018-10-04AE42676ND
2018-10-04AE42679ND
2018-10-04AE42677ND
2019-03-05AE57110ND
2019-03-05AE57111ND
2019-03-05AE57108ND
2019-03-05AE57109ND
2019-04-04AE61172ND
2019-04-04AE61169ND
2019-04-04AE61171ND
2019-04-04AE61170ND
2019-07-10AE74129ND
2019-07-10AE741322.10 ppb
2019-07-10AE74133ND
2019-07-10AE74128ND
2019-10-01AE853301.50 ppb
2019-10-01AE853321.30 ppb
2019-10-01AE853271.50 ppb
2019-10-01AE85329ND