Know Your Environment. Protect Your Health.

Chloroform

Bonney Lake Water Department

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.

 

48

Samples

0

Samples exceeding legal limit (MCL)

42

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20182.71 ppb10100.500 ppb - 6.19 ppb
20191.36 ppb880.560 ppb - 5.00 ppb
2020N/A00N/A
20212.38 ppb87ND - 11.1 ppb
20222.06 ppb87ND - 7.20 ppb
20231.47 ppb1410ND - 7.24 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.

ppb = parts per billion

All test results

Date Lab ID Result
2018-03-141.40 ppb
2018-03-140.500 ppb
2018-05-152.47 ppb
2018-05-154.40 ppb
2018-06-063.00 ppb
2018-06-061.87 ppb
2018-09-206.19 ppb
2018-09-204.74 ppb
2018-12-171.73 ppb
2018-12-170.790 ppb
2019-03-180.610 ppb
2019-03-181.02 ppb
2019-05-220.970 ppb
2019-05-221.41 ppb
2019-08-130.620 ppb
2019-08-135.00 ppb
2019-11-210.560 ppb
2019-11-210.680 ppb
2021-04-0741024710.610 ppb
2021-04-074102472ND
2021-05-2441260911.03 ppb
2021-05-2441260920.800 ppb
2021-08-12415929911.1 ppb
2021-08-1241592981.94 ppb
2021-11-1742075252.78 ppb
2021-11-1742075270.740 ppb
2022-02-0942418030.590 ppb
2022-02-094241804ND
2022-05-1042868290.800 ppb
2022-05-1042868282.78 ppb
2022-08-1643639077.20 ppb
2022-08-1643639092.59 ppb
2022-11-0843748751.19 ppb
2022-11-0843748771.34 ppb
2023-02-074411914ND
2023-02-0744119151.41 ppb
2023-04-1044442911.90 ppb
2023-04-1044442941.44 ppb
2023-05-2244663292.04 ppb
2023-05-2244663320.890 ppb
2023-07-244509854ND
2023-07-244509852ND
2023-07-244509855ND
2023-07-2445098580.980 ppb
2023-09-1245257820.870 ppb
2023-09-1245257837.24 ppb
2023-11-2745564293.13 ppb
2023-11-2745564260.680 ppb