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EWG's Tap Water Database — 2019 UPDATE

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Total trihalomethanes (TTHMs)

City of Liberal

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.

 

61

Samples

0

Samples exceeding legal limit (MCL)

25

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND10ND
20131.98 ppb53ND - 5.50 ppb
20144.08 ppb167ND - 23.0 ppb
20152.85 ppb167ND - 12.0 ppb
20164.69 ppb124ND - 27.0 ppb
20176.91 ppb114ND - 46.4 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
2012-08-06583373TFND
2013-08-19601870TF2.10 ppb
2013-11-12605593TFND
2013-11-12605594TF5.50 ppb
2013-11-12605595TFND
2013-11-12605596TF2.30 ppb
2014-02-1060220ND
2014-02-10602212.19 ppb
2014-02-106022219.6 ppb
2014-02-1060223ND
2014-05-05110670ND
2014-05-05110669ND
2014-05-0511066812.0 ppb
2014-05-05110671ND
2014-08-18175995ND
2014-08-18175993ND
2014-08-1817599223.0 ppb
2014-08-18175994ND
2014-11-182339434.50 ppb
2014-11-18233945ND
2014-11-182339472.00 ppb
2014-11-182339492.00 ppb
2015-02-092772429.00 ppb
2015-02-09277241ND
2015-02-09277240ND
2015-02-09277239ND
2015-05-113318393.40 ppb
2015-05-1133183812.0 ppb
2015-05-113318372.00 ppb
2015-05-11331836ND
2015-08-313970342.80 ppb
2015-08-31397037ND
2015-08-31397036ND
2015-08-3139703512.0 ppb
2015-11-02427997ND
2015-11-02428000ND
2015-11-02427998ND
2015-11-024279994.40 ppb
2016-02-29500710ND
2016-02-29500713ND
2016-02-29500711ND
2016-02-2950071211.0 ppb
2016-05-1654772716.0 ppb
2016-05-16547728ND
2016-05-16547729ND
2016-05-16547730ND
2016-08-22608719ND
2016-08-226087172.30 ppb
2016-08-22608720ND
2016-08-2260871827.0 ppb
2017-08-2983005913.0 ppb
2017-08-29830068ND
2017-11-07873209_PACE46.4 ppb
2017-11-07873202_PACE2.20 ppb
2017-11-07873205_PACEND
2017-11-07873205ND
2017-11-07873171_PACEND
2017-11-07873170_PACEND
2017-11-07873169_PACEND
2017-11-07873172_PACEND
2017-11-07873204_PACE14.4 ppb