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EWG's Tap Water Database — 2021 UPDATE

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Haloacetic acids (HAA5)

Dover Water Department

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

 

64

Samples

0

Samples exceeding legal limit (MCL)

38

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
2014N/A00N/A
2015N/A00N/A
20161.36 ppb169ND - 5.20 ppb
20171.01 ppb167ND - 4.20 ppb
20181.76 ppb1614ND - 4.30 ppb
20190.931 ppb168ND - 3.80 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
2016-02-10B6006430021.30 ppb
2016-02-10B6006430035.20 ppb
2016-02-10B6006430043.20 ppb
2016-02-10B6006430011.40 ppb
2016-05-17B602906001ND
2016-05-17B602906002ND
2016-05-17B6029060031.20 ppb
2016-05-17B6029060041.50 ppb
2016-08-16B6075670023.00 ppb
2016-08-16B607567004ND
2016-08-16B6075670033.20 ppb
2016-08-16B6075670011.70 ppb
2016-11-14B610194001ND
2016-11-14B610194002ND
2016-11-14B610194003ND
2016-11-14B610194004ND
2017-02-15B700692002ND
2017-02-15B700692004ND
2017-02-15B7006920034.20 ppb
2017-02-15B700692001ND
2017-05-16B702573001ND
2017-05-16B7025730021.20 ppb
2017-05-16B7025730033.80 ppb
2017-05-16B7025730041.20 ppb
2017-08-14B707045001ND
2017-08-14B707045002ND
2017-08-14B707045003ND
2017-08-14B707045004ND
2017-11-15B7098940012.30 ppb
2017-11-15B709894002ND
2017-11-15B7098940032.50 ppb
2017-11-15B7098940041.000 ppb
2018-02-12B8005580014.30 ppb
2018-02-12B8005580044.30 ppb
2018-02-12B8005580021.70 ppb
2018-02-12B8005580032.40 ppb
2018-05-17B8026010011.30 ppb
2018-05-17B8026010021.10 ppb
2018-05-17B8026010032.00 ppb
2018-05-18B8026430011.90 ppb
2018-08-15B8069550011.000 ppb
2018-08-15B806955002ND
2018-08-15B806955003ND
2018-08-15B8069550041.70 ppb
2018-11-15B8096310011.10 ppb
2018-11-15B8096310021.000 ppb
2018-11-15B8096310031.20 ppb
2018-11-15B8096310043.10 ppb
2019-02-11B9007560021.20 ppb
2019-02-11B900756004ND
2019-02-11B9007560031.90 ppb
2019-02-11B900756001ND
2019-05-15B9028800011.20 ppb
2019-05-15B9028800021.10 ppb
2019-05-15B9028800033.80 ppb
2019-05-15B9028800042.20 ppb
2019-08-13B907249001ND
2019-08-13B907249002ND
2019-08-13B907249003ND
2019-08-13B907249004ND
2019-11-14B9100960011.90 ppb
2019-11-14B9100960021.60 ppb
2019-11-14B910096003ND
2019-11-14B910096004ND