Know Your Environment. Protect Your Health.

Haloacetic acids (HAA5)

City of Nampa

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.

 

100

Samples

0

Samples exceeding legal limit (MCL)

60

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.629 ppb168ND - 1.65 ppb
20191.18 ppb2012ND - 2.97 ppb
20201.07 ppb1610ND - 2.26 ppb
20210.961 ppb169ND - 3.30 ppb
20221.16 ppb1610ND - 3.56 ppb
20231.17 ppb1611ND - 2.87 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

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
2018-01-10D1801343ND
2018-01-10D18013441.65 ppb
2018-01-10D18013461.27 ppb
2018-01-10D18013451.13 ppb
2018-05-02D18195781.17 ppb
2018-05-02D18195771.08 ppb
2018-05-02D1819576ND
2018-05-02D1819575ND
2018-08-13D1839491ND
2018-08-13D18394941.17 ppb
2018-08-13D18394931.56 ppb
2018-08-13D18394921.03 ppb
2018-10-08D1850031ND
2018-10-08D1850034ND
2018-10-08D1850033ND
2018-10-08D1850032ND
2019-01-30D19043391.13 ppb
2019-01-30D19043381.31 ppb
2019-01-30D1904337ND
2019-01-30D1904336ND
2019-05-08D19211972.64 ppb
2019-05-08D19211982.97 ppb
2019-05-08D1921195ND
2019-05-08D19211961.23 ppb
2019-07-18D1935121ND
2019-07-18D19351222.83 ppb
2019-07-18D1935123ND
2019-07-18D1935124ND
2019-09-18D1947011ND
2019-09-18D19470141.71 ppb
2019-09-18D19470132.72 ppb
2019-09-18D19470122.25 ppb
2019-12-31D19645761.000 ppb
2019-12-31D1964575ND
2019-12-31D19645741.77 ppb
2019-12-31D19645732.04 ppb
2020-02-12D2006564ND
2020-02-12D2006565ND
2020-02-12D20065632.05 ppb
2020-02-12D20065622.23 ppb
2020-06-02D20253491.16 ppb
2020-06-02D2025348ND
2020-06-02D20253471.91 ppb
2020-06-02D20253462.26 ppb
2020-08-31D2042977ND
2020-08-31D20429761.40 ppb
2020-08-31D20429751.75 ppb
2020-08-31D20429781.15 ppb
2020-10-01D20491631.70 ppb
2020-10-01D2049165ND
2020-10-01D20491621.46 ppb
2020-10-01D2049164ND
2021-01-20D2102942ND
2021-01-20D2102940ND
2021-01-20D2102941ND
2021-01-20D21029391.38 ppb
2021-04-21D21183021.02 ppb
2021-04-21D2118303ND
2021-04-21D21183011.45 ppb
2021-04-21D21183041.95 ppb
2021-08-04D2139750ND
2021-08-04D2139746ND
2021-08-04D21397493.30 ppb
2021-08-04D2139747ND
2021-11-09D21608442.45 ppb
2021-11-09D21608451.68 ppb
2021-11-09D21608461.05 ppb
2021-11-09D21608471.10 ppb
2022-02-02D22053072.45 ppb
2022-02-02D22053081.98 ppb
2022-02-02D22053091.41 ppb
2022-02-02D22053101.82 ppb
2022-06-09D2227608ND
2022-06-09D2227607ND
2022-06-09D2227606ND
2022-06-09D22276051.93 ppb
2022-08-19D2240994ND
2022-08-19T2240993ND
2022-08-19D22409921.27 ppb
2022-08-19D22409911.93 ppb
2022-11-16D22569821.10 ppb
2022-11-16D2256983ND
2022-11-16D22569841.18 ppb
2022-11-16D22569813.56 ppb
2023-02-01PP2302075-042.08 ppb
2023-02-01PP2302075-03ND
2023-02-01PP2302075-022.00 ppb
2023-02-01PP2302075-011.11 ppb
2023-05-10PP2309048-011.84 ppb
2023-05-10PP2309048-021.28 ppb
2023-05-10PP2309048-03ND
2023-05-10PP2309048-04ND
2023-08-02D2316309-012.87 ppb
2023-08-02D2316309-021.53 ppb
2023-08-02D2316309-03ND
2023-08-02D2316309-041.39 ppb
2023-10-16D2322558-041.01 ppb
2023-10-16D2322558-03ND
2023-10-16D2322558-022.50 ppb
2023-10-16D2322558-011.12 ppb