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EWG's Tap Water Database — 2021 UPDATE

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Haloacetic acids (HAA5)

Ontario Municipal Utilities Company

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

 

185

Samples

0

Samples exceeding legal limit (MCL)

104

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
201411.9 ppb3229ND - 33.0 ppb
201511.8 ppb3228ND - 43.0 ppb
20162.80 ppb254ND - 19.0 ppb
20173.54 ppb3215ND - 14.0 ppb
20183.90 ppb3213ND - 13.0 ppb
20194.73 ppb3215ND - 17.0 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
2014-02-204790-601-082020.0 ppb
2014-02-204790-602-07453.10 ppb
2014-02-204790-603-085523.0 ppb
2014-02-204790-604-112533.0 ppb
2014-02-204790-605-110531.0 ppb
2014-02-204790-606-080022.0 ppb
2014-02-204790-607-111533.0 ppb
2014-02-204790-608-084024.0 ppb
2014-05-214790-601-08208.10 ppb
2014-05-214790-602-0729ND
2014-05-214790-603-08559.20 ppb
2014-05-214790-604-11459.30 ppb
2014-05-214790-605-111513.0 ppb
2014-05-214790-606-08008.60 ppb
2014-05-214790-607-11308.30 ppb
2014-05-214790-608-08408.40 ppb
2014-08-214790-601-08272.60 ppb
2014-08-214790-602-07583.20 ppb
2014-08-214790-603-0900ND
2014-08-214790-604-105116.0 ppb
2014-08-214790-605-111612.0 ppb
2014-08-214790-606-0813ND
2014-08-214790-607-110324.0 ppb
2014-08-214790-608-084512.0 ppb
2014-11-204790-601-08203.00 ppb
2014-11-204790-602-07302.80 ppb
2014-11-204790-603-09103.20 ppb
2014-11-204790-604-114511.0 ppb
2014-11-204790-605-112511.0 ppb
2014-11-204790-606-08003.40 ppb
2014-11-204790-607-113512.0 ppb
2014-11-204790-608-084011.0 ppb
2015-02-194790-601-07557.20 ppb
2015-02-194790-602-07302.30 ppb
2015-02-194790-603-082514.0 ppb
2015-02-194790-604-110510.00 ppb
2015-02-194790-605-104511.0 ppb
2015-02-194790-606-112510.00 ppb
2015-02-194790-607-10559.80 ppb
2015-02-194790-608-08159.70 ppb
2015-05-214790-601-08177.40 ppb
2015-05-214790-602-07447.40 ppb
2015-05-214790-603-0852ND
2015-05-214790-604-11409.30 ppb
2015-05-214790-605-110820.0 ppb
2015-05-214790-606-08005.80 ppb
2015-05-214790-607-112520.0 ppb
2015-05-214790-608-083814.0 ppb
2015-08-134790-601-09305.70 ppb
2015-08-134790-602-0753ND
2015-08-134790-603-090510.00 ppb
2015-08-134790-604-12256.40 ppb
2015-08-134790-605-12072.30 ppb
2015-08-134790-606-08306.40 ppb
2015-08-134790-607-121543.0 ppb
2015-08-134790-608-09156.40 ppb
2015-11-194790-601-08352.20 ppb
2015-11-194790-602-0750ND
2015-11-194790-603-0910ND
2015-11-194790-604-121035.0 ppb
2015-11-194790-605-114033.0 ppb
2015-11-194790-606-08104.00 ppb
2015-11-194790-607-115534.0 ppb
2015-11-194790-608-085030.0 ppb
2016-02-184790-601-0815ND
2016-05-264790-601-0750ND
2016-05-264790-602-0716ND
2016-05-264790-603-0823ND
2016-05-264790-604-105518.0 ppb
2016-05-264790-605-103419.0 ppb
2016-05-264790-606-0734ND
2016-05-264790-607-104418.0 ppb
2016-05-264790-608-080615.0 ppb
2016-08-254790-601-0811ND
2016-08-254790-602-0730ND
2016-08-254790-603-0841ND
2016-08-254790-604-1115ND
2016-08-254790-605-1134ND
2016-08-254790-606-0749ND
2016-08-254790-607-1124ND
2016-08-254790-608-0824ND
2016-11-174790-601-0802ND
2016-11-174790-602-0715ND
2016-11-174790-603-0847ND
2016-11-174790-604-1136ND
2016-11-174790-605-1113ND
2016-11-174790-606-0736ND
2016-11-174790-607-1123ND
2016-11-174790-608-0820ND
2017-02-234790-601-1000ND
2017-02-234790-602-0920ND
2017-02-234790-603-1040ND
2017-02-234790-604-1105ND
2017-02-234790-605-1135ND
2017-02-234790-606-0945ND
2017-02-234790-607-1115ND
2017-02-234790-608-1020ND
2017-05-114790-601-0835ND
2017-05-114790-602-0745ND
2017-05-114790-603-09254.20 ppb
2017-05-114790-604-121014.0 ppb
2017-05-114790-605-11509.20 ppb
2017-05-114790-606-0810ND
2017-05-114790-608-08502.60 ppb
2017-05-304790-607-145213.0 ppb
2017-08-104790-601-08303.60 ppb
2017-08-104790-602-0740ND
2017-08-104790-603-0905ND
2017-08-104790-604-12007.20 ppb
2017-08-104790-605-11257.40 ppb
2017-08-104790-606-0805ND
2017-08-104790-607-11407.90 ppb
2017-08-104790-608-08558.00 ppb
2017-11-164790-601-08352.50 ppb
2017-11-164790-602-0740ND
2017-11-164790-603-0920ND
2017-11-164790-604-12109.30 ppb
2017-11-164790-605-11429.40 ppb
2017-11-164790-606-0805ND
2017-11-164790-607-11558.60 ppb
2017-11-164790-608-09006.40 ppb
2018-02-084790-601-0820ND
2018-02-084790-602-0740ND
2018-02-084790-603-0905ND
2018-02-084790-604-1145ND
2018-02-084790-605-1120ND
2018-02-084790-606-0800ND
2018-02-084790-607-1135ND
2018-02-084790-608-085010.00 ppb
2018-05-104790-601-0825ND
2018-05-104790-602-0740ND
2018-05-104790-603-0905ND
2018-05-104790-604-12058.10 ppb
2018-05-104790-605-1135ND
2018-05-104790-606-0805ND
2018-05-104790-607-11508.90 ppb
2018-05-104790-608-08459.10 ppb
2018-08-094790-601-0850ND
2018-08-094790-602-0800ND
2018-08-094790-603-0930ND
2018-08-094790-604-123512.0 ppb
2018-08-094790-605-120513.0 ppb
2018-08-094790-606-08252.80 ppb
2018-08-094790-607-122012.0 ppb
2018-08-094790-608-091012.0 ppb
2018-11-154790-601-0830ND
2018-11-154790-602-0740ND
2018-11-154790-603-0910ND
2018-11-154790-604-121011.0 ppb
2018-11-154790-605-11409.90 ppb
2018-11-154790-606-0800ND
2018-11-154790-607-11559.60 ppb
2018-11-154790-608-08556.50 ppb
2019-02-134790-601-11302.30 ppb
2019-02-134790-602-1210ND
2019-02-134790-603-10553.80 ppb
2019-02-134790-604-103514.0 ppb
2019-02-134790-605-101016.0 ppb
2019-02-134790-606-1150ND
2019-02-134790-607-102013.0 ppb
2019-02-134790-608-111015.0 ppb
2019-05-094790-601-0900ND
2019-05-094790-602-0815ND
2019-05-094790-603-0955ND
2019-05-094790-604-101513.0 ppb
2019-05-094790-605-104513.0 ppb
2019-05-094790-606-0835ND
2019-05-094790-607-103012.0 ppb
2019-05-094790-608-093512.0 ppb
2019-08-154790-601-0805ND
2019-08-154790-602-07253.30 ppb
2019-08-154790-603-08503.10 ppb
2019-08-154790-604-1200ND
2019-08-154790-605-1125ND
2019-08-154790-606-07452.80 ppb
2019-08-154790-607-1140ND
2019-08-154790-608-0830ND
2019-11-144790-601-0810ND
2019-11-144790-602-0735ND
2019-11-144790-603-085017.0 ppb
2019-11-144790-604-1135ND
2019-11-144790-605-1110ND
2019-11-144790-606-075011.0 ppb
2019-11-144790-607-1125ND
2019-11-144790-608-0825ND