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Chloroform

Warminster Municipal Authority

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Read More.

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

 

64

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2010N/A00N/A
20110.118 ppb61ND - 0.710 ppb
20120.0967 ppb122ND - 0.650 ppb
20136.19 ppb1411ND - 20.6 ppb
20141.79 ppb1611ND - 6.20 ppb
20153.30 ppb16160.540 ppb - 11.0 ppb

ppb = parts per billion.

State and national drinking water standards and health guidelines

Health Guideline 0.4 ppb

The health guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion.

EPA Maximum Contaminant
Level Goal (MCLG)70.0 ppb

A non-enforceable federal health guideline. For cancer-causing chemicals, these health goals are typically set to zero.

ppb = parts per billion.

All test results

Date Lab ID Result
2011-09-169927086001ND
2011-09-169927086002ND
2011-09-169927086003ND
2011-12-0699410750030.710 ppb
2011-12-069941075001ND
2011-12-069941075002ND
2012-02-289954523003ND
2012-02-289954523001ND
2012-02-289954523002ND
2012-05-189968603002ND
2012-05-189968603003ND
2012-05-189968603001ND
2012-09-189989149003ND
2012-09-1899891490020.650 ppb
2012-09-189989149001ND
2012-11-089997627003ND
2012-11-0899976270020.510 ppb
2012-11-089997627001ND
2013-02-201013258002ND
2013-02-201013258001ND
2013-02-201013258003ND
2013-05-2110282890010.680 ppb
2013-05-2110282890020.890 ppb
2013-05-2110282890031.10 ppb
2013-08-2010442080030.940 ppb
2013-08-2010442080011.000 ppb
2013-08-2010442080020.900 ppb
2013-08-2010442080045.80 ppb
2013-11-20105998900419.3 ppb
2013-11-20105998900120.5 ppb
2013-11-20105998900314.9 ppb
2013-11-20105998900220.6 ppb
2014-02-191072699002ND
2014-02-1910726990031.000 ppb
2014-02-1910726990040.540 ppb
2014-02-191072699001ND
2014-05-2020078510034.70 ppb
2014-05-2020078510042.30 ppb
2014-05-202007851001ND
2014-05-202007851002ND
2014-08-1920247290032.90 ppb
2014-08-1920247290046.20 ppb
2014-08-192024729002ND
2014-09-0520276700010.710 ppb
2014-11-1720407200020.730 ppb
2014-11-1720407200043.40 ppb
2014-11-1720407200010.870 ppb
2014-11-1720407200035.30 ppb
2015-02-18123894120.540 ppb
2015-02-18123894060.610 ppb
2015-02-18123894241.90 ppb
2015-02-18123894181.90 ppb
2015-05-18127375444.60 ppb
2015-05-18127375507.60 ppb
2015-05-18127375380.670 ppb
2015-05-18127375320.590 ppb
2015-08-19131227678.40 ppb
2015-08-19131227610.640 ppb
2015-08-191312277311.0 ppb
2015-08-19131227550.720 ppb
2015-11-20135023640.860 ppb
2015-11-20135023706.50 ppb
2015-11-20135023765.50 ppb
2015-11-20135023580.720 ppb