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EWG's Tap Water Database — 2021 UPDATE

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Haloacetic acids (HAA5)

Carson City Public Works

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

 

186

Samples

19

Samples exceeding legal limit (MCL)

88

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201417.7 ppb3215ND - 73.7 ppb
201518.3 ppb3213ND - 86.3 ppb
201618.9 ppb3211ND - 98.7 ppb
20178.74 ppb3314ND - 63.4 ppb
20188.79 ppb2512ND - 29.6 ppb
201917.8 ppb3223ND - 69.9 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
2014-01-28201401300174ND
2014-01-2820140130017556.3 ppb
2014-01-2820140130017643.8 ppb
2014-01-2820140130017758.8 ppb
2014-01-2820140130017868.4 ppb
2014-01-2820140130017973.7 ppb
2014-01-2820140130018068.7 ppb
2014-01-2820140130018127.9 ppb
2014-04-08201404120248ND
2014-04-08201404120249ND
2014-04-0820140412025036.1 ppb
2014-04-08201404120251ND
2014-04-08201404120252ND
2014-04-08201404120253ND
2014-04-082014041202543.55 ppb
2014-04-08201404120255ND
2014-07-28201407300263ND
2014-07-282014073002643.26 ppb
2014-07-2820140730026562.7 ppb
2014-07-28201407300266ND
2014-07-2820140730026713.8 ppb
2014-07-282014073002681.50 ppb
2014-07-2820140730026911.1 ppb
2014-07-28201407300270ND
2014-10-27201410290440ND
2014-10-27201410290441ND
2014-10-2720141029044237.6 ppb
2014-10-27201410290443ND
2014-10-27201410290444ND
2014-10-27201410290445ND
2014-10-27201410290446ND
2014-10-27201410290447ND
2015-01-26201501280717ND
2015-01-2620150128071848.7 ppb
2015-01-2620150128071969.9 ppb
2015-01-26201501280720ND
2015-01-2620150128072167.0 ppb
2015-01-2620150128072286.3 ppb
2015-01-2620150128072384.3 ppb
2015-01-2620150128072479.8 ppb
2015-04-28201504300112ND
2015-04-28201504300113ND
2015-04-2820150430011437.0 ppb
2015-04-28201504300115ND
2015-04-28201504300116ND
2015-04-28201504300117ND
2015-04-28201504300118ND
2015-04-28201504300119ND
2015-07-28201507300229ND
2015-07-2820150730023011.1 ppb
2015-07-2820150730023144.1 ppb
2015-07-28201507300232ND
2015-07-28201507300233ND
2015-07-28201507300234ND
2015-07-282015073002351.16 ppb
2015-07-28201507300236ND
2015-10-12201510140539ND
2015-10-12201510140540ND
2015-10-1220151014054153.2 ppb
2015-10-12201510140542ND
2015-10-122015101405431.08 ppb
2015-10-122015101405441.18 ppb
2015-10-12201510140545ND
2015-10-12201510140546ND
2016-01-202016012202258.35 ppb
2016-01-2020160122022666.8 ppb
2016-01-2020160122022773.3 ppb
2016-01-202016012202281.66 ppb
2016-01-2020160122022994.6 ppb
2016-01-2020160122023098.6 ppb
2016-01-2020160122023198.7 ppb
2016-01-2020160122023298.4 ppb
2016-04-26201604280378ND
2016-04-262016042803791.08 ppb
2016-04-2620160428038060.6 ppb
2016-04-26201604280381ND
2016-04-262016042803822.15 ppb
2016-04-26201604280383ND
2016-04-27201604280384ND
2016-04-27201604280385ND
2016-07-2720160280420ND
2016-07-27201607280421ND
2016-07-27201607280422ND
2016-07-27201607280423ND
2016-07-27201607280424ND
2016-07-27201607280425ND
2016-07-27201607280426ND
2016-07-27201607280430ND
2016-10-12201610130512ND
2016-10-12201610130513ND
2016-10-12201610130514ND
2016-10-12201610130515ND
2016-10-12201610130516ND
2016-10-12201610130517ND
2016-10-12201610130518ND
2016-10-12201610130519ND
2017-01-2520170127042815.4 ppb
2017-01-252017012704294.69 ppb
2017-01-2520170127043032.5 ppb
2017-01-2520170127043115.3 ppb
2017-01-2520170127043322.3 ppb
2017-01-2520170127043460.8 ppb
2017-01-2520170127043535.1 ppb
2017-01-252017127043216.8 ppb
2017-02-212017022209280.995 ppb
2017-04-2420170426076363.4 ppb
2017-04-24201704260764ND
2017-04-24201704260765ND
2017-04-24201704260766ND
2017-04-242017042607675.40 ppb
2017-04-242017042607684.80 ppb
2017-04-24201704260769ND
2017-04-24201704260770ND
2017-07-182017071906909.63 ppb
2017-07-18201707190691ND
2017-07-18201707190692ND
2017-07-18201707190693ND
2017-07-18201707190694ND
2017-07-18201707190695ND
2017-07-18201707190696ND
2017-07-18201707190697ND
2017-10-052017100601501.36 ppb
2017-10-05201710060152ND
2017-10-05201710060153ND
2017-10-05201710060154ND
2017-10-05201710060155ND
2017-10-05201710060156ND
2017-10-05201710060157ND
2017-10-16201710170612ND
2018-02-272018022804329.70 ppb
2018-02-2720180228043527.4 ppb
2018-02-27201802280436ND
2018-02-2720180228043729.4 ppb
2018-02-2720180228043824.3 ppb
2018-02-2720180228043929.0 ppb
2018-02-2720180228044029.6 ppb
2018-02-272018022804411.000 ppb
2018-05-102018051106405.86 ppb
2018-05-102018051106418.12 ppb
2018-07-24201807260438ND
2018-07-2420180726043922.3 ppb
2018-07-2420180726044019.6 ppb
2018-07-24201807260441ND
2018-07-24201807260442ND
2018-07-24201807260443ND
2018-07-24201807260444ND
2018-07-24201807260445ND
2018-10-18201810190600ND
2018-10-18201810190601ND
2018-10-18201810190602ND
2018-10-1820181019060313.4 ppb
2018-10-18201810190604ND
2018-10-18201810190605ND
2018-10-18201810190607ND
2019-01-232019012404273.30 ppb
2019-01-2320190124042826.5 ppb
2019-01-232019012404294.22 ppb
2019-01-2320190124043019.3 ppb
2019-01-2320190124043125.7 ppb
2019-01-2320190124043226.8 ppb
2019-01-2320190124043326.5 ppb
2019-01-232019012404342.88 ppb
2019-04-23201904250221ND
2019-04-2320190425022240.1 ppb
2019-04-2320190425022328.5 ppb
2019-04-232019042502241.44 ppb
2019-04-2420190425022543.0 ppb
2019-04-2420190425022644.7 ppb
2019-04-2420190425022738.1 ppb
2019-04-242019042502283.18 ppb
2019-07-23201907240474ND
2019-07-2320190724047569.9 ppb
2019-07-2320190724047652.7 ppb
2019-07-2320190724047739.6 ppb
2019-07-2320190724047827.9 ppb
2019-07-232019072404795.51 ppb
2019-07-232019072404805.63 ppb
2019-07-232019072404815.63 ppb
2019-10-22201910230717ND
2019-10-22201910230718ND
2019-10-2220191023071927.5 ppb
2019-10-22201910230720ND
2019-10-22201910230721ND
2019-10-22201910230722ND
2019-10-22201910230723ND
2019-10-22201910230724ND