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EWG's Tap Water Database — 2021 UPDATE

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Total trihalomethanes (TTHMs)

Oneonta City

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.

 

87

Samples

13

Samples exceeding legal limit (MCL)

87

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
201451.6 ppb121231.9 ppb - 94.8 ppb
201558.3 ppb111125.0 ppb - 108.3 ppb
201659.8 ppb161619.0 ppb - 110.0 ppb
201752.2 ppb161618.6 ppb - 109.0 ppb
201846.7 ppb161623.6 ppb - 82.6 ppb
201952.2 ppb161617.1 ppb - 98.6 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
2014-02-12140216902A31.9 ppb
2014-02-121402169037.3 ppb
2014-02-12140216903A63.3 ppb
2014-02-12140216904A94.8 ppb
2014-05-1414053036004A55.4 ppb
2014-05-1414053036A49.7 ppb
2014-05-1414053036006A44.1 ppb
2014-05-1414053036005A60.3 ppb
2014-11-19S4K1798-0233.1 ppb
2014-11-19S4K1787-0141.4 ppb
2014-11-19S4K1787-0342.5 ppb
2014-11-19S4K1787-0465.9 ppb
2015-02-181502C77-00125.0 ppb
2015-02-181502C77-00243.0 ppb
2015-02-181502C77-00447.0 ppb
2015-02-181502C77-00366.0 ppb
2015-05-13AS0945044.8 ppb
2015-05-13AS0944962.8 ppb
2015-05-13AS0944841.9 ppb
2015-05-13AS0945154.1 ppb
2015-08-19H32EEL82.0 ppb
2015-08-19H32WWTP66.0 ppb
2015-08-19H32HC108.3 ppb
2016-02-101292-00436.0 ppb
2016-02-101292-00337.0 ppb
2016-02-101292-00619.0 ppb
2016-02-101292-00528.0 ppb
2016-05-111604910-00547.0 ppb
2016-05-111604910-00468.0 ppb
2016-05-111604910-00752.0 ppb
2016-05-111604910-00640.0 ppb
2016-08-171608789-003110.0 ppb
2016-08-171608789-004110.0 ppb
2016-08-171608789-00691.0 ppb
2016-08-171608789-00572.0 ppb
2016-11-09EEL DBP 4Q1656.0 ppb
2016-11-09WWTP DBP 4Q1642.0 ppb
2016-11-09HC DBP 4Q1667.0 ppb
2016-11-09BB THM 4Q1682.0 ppb
2017-02-08WWP DBP 2-1724.0 ppb
2017-02-08HC DBP 2-1742.1 ppb
2017-02-08EEL HAA 2-1733.5 ppb
2017-02-08BB DBP 2-1718.6 ppb
2017-05-10COWWPDBP5201732.4 ppb
2017-05-10COEELDBP5201751.3 ppb
2017-05-10COBSDBP5201725.9 ppb
2017-05-10COHCDBP5201749.6 ppb
2017-08-16225535-EELAU68.4 ppb
2017-08-16225535-WWTP60.1 ppb
2017-08-16225535-HART109.0 ppb
2017-08-16225535-BUG96.2 ppb
2017-11-08WWTP 4Q 1748.3 ppb
2017-11-08HART COLLEG 4Q 162.8 ppb
2017-11-08BUGBEE 4Q 17 DBP63.1 ppb
2017-11-08EEL ONEONTA 118150.5 ppb
2018-02-14704314000628.5 ppb
2018-02-14704314000523.6 ppb
2018-03-05704450000229.1 ppb
2018-03-05704450000135.3 ppb
2018-05-0839700348.1 ppb
2018-05-0839700439.5 ppb
2018-05-0839700640.0 ppb
2018-05-0839700533.1 ppb
2018-08-089500353.5 ppb
2018-08-089500651.8 ppb
2018-08-089500482.6 ppb
2018-08-089500557.5 ppb
2018-11-14EEL DBP 11201838.0 ppb
2018-11-14HART DBP 11201873.2 ppb
2018-11-14BUG DBP 11201860.7 ppb
2018-11-14WWTP DBP 11201852.9 ppb
2019-02-127079734004DBP21.0 ppb
2019-02-127079734006DBP17.1 ppb
2019-02-12707973400532.8 ppb
2019-02-127079734007DBP23.2 ppb
2019-05-07708899500356.1 ppb
2019-05-07708899500439.4 ppb
2019-05-077008899500660.2 ppb
2019-05-07708899500546.5 ppb
2019-08-20ONE EEL DBP 3Q1962.5 ppb
2019-08-20ONE BUG DBP 3Q1992.2 ppb
2019-08-20ONE HART DBP 3Q198.6 ppb
2019-08-20ONE WWTP DBP 3Q175.3 ppb
2019-10-13DBP EEL 4Q1933.0 ppb
2019-10-13WWTP DBP 4Q1944.0 ppb
2019-10-13BUGBEE DBP 4Q1950.3 ppb
2019-10-13HART DBP 4Q1982.4 ppb