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EWG's Tap Water Database — 2021 UPDATE

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Total trihalomethanes (TTHMs)

Beaumont Cherry Valley WD

Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform. Read More.

Studies conducted in the U.S. and Europe have found that drinking tap water that carries disinfection byproducts increases the risk of developing bladder cancer. In animal studies, all trihalomethanes cause liver, kidney and intestinal tumors. Some human epidemiological studies also reported an association between disinfection byproducts and an increased risk of problems during pregnancy, including spontaneous miscarriage, cardiovascular defects, neural tube defects and low birth weight.

The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.

Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

 

105

Samples

0

Samples exceeding legal limit (MCL)

69

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20141.72 ppb105ND - 5.60 ppb
20152.06 ppb2013ND - 6.40 ppb
20162.50 ppb1512ND - 5.50 ppb
20172.28 ppb2014ND - 5.80 ppb
20181.45 ppb2010ND - 7.00 ppb
20192.59 ppb2015ND - 8.00 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.15 ppb

The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.

EPA Maximum Contaminant
Level (MCL) 80 ppb

The legal limit for the group of four trihalomethanes, 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 due to exposure to trihalomethanes.

ppb = parts per billion

All test results

Date Lab ID Result
2014-03-174790-801-1141ND
2014-03-174790-802-1119ND
2014-03-174790-803-1020ND
2014-03-174790-804-09363.60 ppb
2014-03-174790-805-1331ND
2014-12-164790-801-09461.90 ppb
2014-12-164790-802-07374.70 ppb
2014-12-164790-803-0900ND
2014-12-164790-804-08265.60 ppb
2014-12-164790-805-10061.40 ppb
2015-03-164790-801-1311ND
2015-03-164790-802-1434ND
2015-03-164790-803-13404.40 ppb
2015-03-164790-804-14104.80 ppb
2015-03-164790-805-15021.30 ppb
2015-06-184790-801-0800ND
2015-06-184790-802-08303.20 ppb
2015-06-184790-803-0927ND
2015-06-184790-804-09506.40 ppb
2015-06-184790-805-1005ND
2015-09-174790-801-13342.20 ppb
2015-09-174790-802-12153.60 ppb
2015-09-174790-803-1240ND
2015-09-174790-804-13002.30 ppb
2015-09-174790-805-14141.20 ppb
2015-12-144790-801-12012.50 ppb
2015-12-144790-802-0911ND
2015-12-144790-803-13224.10 ppb
2015-12-144790-804-12442.90 ppb
2015-12-144790-805-14002.30 ppb
2016-03-154790-801-12472.20 ppb
2016-03-154790-802-0941ND
2016-03-154790-803-12004.50 ppb
2016-03-154790-804-11553.40 ppb
2016-03-154790-805-13311.40 ppb
2016-06-144790-801-1233ND
2016-06-144790-802-1040ND
2016-06-144790-803-11273.40 ppb
2016-06-144790-804-11542.40 ppb
2016-06-144790-805-14142.60 ppb
2016-12-204790-801-12572.80 ppb
2016-12-204790-802-12305.50 ppb
2016-12-204790-803-11324.50 ppb
2016-12-204790-804-09363.10 ppb
2016-12-204790-805-13311.70 ppb
2017-03-224790-801-15150.540 ppb
2017-03-224790-802-13204.50 ppb
2017-03-224790-803-13452.20 ppb
2017-03-224790-804-14055.80 ppb
2017-03-224790-805-14350.500 ppb
2017-06-214790-801-0948ND
2017-06-214790-802-10483.10 ppb
2017-06-214790-803-1318ND
2017-06-214790-804-12304.10 ppb
2017-06-214790-805-1355ND
2017-09-204790-801-13133.60 ppb
2017-09-204790-802-12023.40 ppb
2017-09-204790-803-1243ND
2017-09-204790-804-12585.40 ppb
2017-09-204790-805-1326ND
2017-12-194790-801-0722ND
2017-12-194790-802-09302.70 ppb
2017-12-194790-803-08054.00 ppb
2017-12-194790-804-08314.60 ppb
2017-12-194790-805-10001.10 ppb
2018-03-214790-801-1130ND
2018-03-214790-802-12107.00 ppb
2018-03-214790-803-12350.530 ppb
2018-03-214790-804-13004.50 ppb
2018-03-214790-805-13353.40 ppb
2018-06-214790-801-0950ND
2018-06-214790-802-1100ND
2018-06-214790-803-1130ND
2018-06-214790-804-10452.70 ppb
2018-06-214790-805-10202.60 ppb
2018-09-184790-801-1328ND
2018-09-184790-802-08132.30 ppb
2018-09-184790-803-1122ND
2018-09-184790-804-1008ND
2018-09-184790-805-1444ND
2018-12-174790-801-08101.90 ppb
2018-12-174790-802-0920ND
2018-12-174790-803-0940ND
2018-12-174790-804-10053.50 ppb
2018-12-174790-805-08300.530 ppb
2019-03-194790-801-08062.50 ppb
2019-03-194790-802-08561.40 ppb
2019-03-194790-803-10133.10 ppb
2019-03-194790-804-10558.00 ppb
2019-03-194790-805-11452.10 ppb
2019-06-194790-801-08282.30 ppb
2019-06-194790-802-09551.40 ppb
2019-06-194790-803-1144ND
2019-06-194790-804-13385.60 ppb
2019-06-194790-805-1533ND
2019-09-164790-801-1250ND
2019-09-164790-802-12252.50 ppb
2019-09-164790-803-1055ND
2019-09-164790-804-10304.90 ppb
2019-09-164790-805-1155ND
2019-12-184790-801-07301.30 ppb
2019-12-184790-802-11304.10 ppb
2019-12-184790-803-08202.80 ppb
2019-12-184790-804-09206.20 ppb
2019-12-184790-805-10103.60 ppb