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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Cincinnati Public Water System

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.

MORE ABOUT THIS CONTAMINANT

 

420

Samples

0

Samples exceeding legal limit (MCL)

415

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20144.66 ppb48480.590 ppb - 15.2 ppb
20156.82 ppb48480.400 ppb - 38.1 ppb
20165.12 ppb4844ND - 16.1 ppb
20178.62 ppb48480.920 ppb - 25.0 ppb
201812.0 ppb1081080.697 ppb - 37.6 ppb
201912.9 ppb1201200.710 ppb - 35.5 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG 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

All test results

Date Lab ID Result
2014-02-100912725.70 ppb
2014-02-100912736.37 ppb
2014-02-100912744.98 ppb
2014-02-100912755.42 ppb
2014-02-100912772.07 ppb
2014-02-100912783.69 ppb
2014-02-100912792.38 ppb
2014-02-100912804.34 ppb
2014-02-100912813.05 ppb
2014-02-110912714.69 ppb
2014-02-110912763.90 ppb
2014-02-110912824.24 ppb
2014-05-0509130311.3 ppb
2014-05-050913084.66 ppb
2014-05-050913126.36 ppb
2014-05-050913144.55 ppb
2014-05-0609130413.6 ppb
2014-05-0609130515.2 ppb
2014-05-0609130612.6 ppb
2014-05-0609130710.9 ppb
2014-05-060913094.72 ppb
2014-05-060913106.38 ppb
2014-05-060913117.67 ppb
2014-05-060913135.39 ppb
2014-08-040913511.19 ppb
2014-08-040913569.76 ppb
2014-08-040913570.790 ppb
2014-08-0409135811.7 ppb
2014-08-050913600.590 ppb
2014-08-060913522.77 ppb
2014-08-060913532.57 ppb
2014-08-060913542.50 ppb
2014-08-070913501.75 ppb
2014-08-070913550.820 ppb
2014-08-070913592.72 ppb
2014-08-070913610.860 ppb
2014-11-030913661.84 ppb
2014-11-030913711.04 ppb
2014-11-030913771.22 ppb
2014-11-040913671.87 ppb
2014-11-040913682.29 ppb
2014-11-040913693.39 ppb
2014-11-040913702.30 ppb
2014-11-040913726.22 ppb
2014-11-040913731.54 ppb
2014-11-040913747.56 ppb
2014-11-040913751.48 ppb
2014-11-040913760.690 ppb
2015-02-090914074.71 ppb
2015-02-090914089.47 ppb
2015-02-090914096.51 ppb
2015-02-090914108.04 ppb
2015-02-090914129.60 ppb
2015-02-090914134.41 ppb
2015-02-090914163.42 ppb
2015-02-100914066.90 ppb
2015-02-100914114.84 ppb
2015-02-100914144.49 ppb
2015-02-100914156.10 ppb
2015-02-100914175.13 ppb
2015-05-110914356.38 ppb
2015-05-1109143614.5 ppb
2015-05-1109143711.7 ppb
2015-05-1109143815.5 ppb
2015-05-1109144012.9 ppb
2015-05-110914416.07 ppb
2015-05-1109144215.7 ppb
2015-05-110914437.18 ppb
2015-05-110914444.21 ppb
2015-05-1209143413.1 ppb
2015-05-120914396.83 ppb
2015-05-120914456.46 ppb
2015-08-100914656.23 ppb
2015-08-100914702.13 ppb
2015-08-100914677.26 ppb
2015-08-100914685.55 ppb
2015-08-100914697.35 ppb
2015-08-1009147317.4 ppb
2015-08-100914745.48 ppb
2015-08-100914751.03 ppb
2015-08-100914762.21 ppb
2015-08-110914669.88 ppb
2015-08-1109147138.1 ppb
2015-08-110914721.71 ppb
2015-11-090914930.800 ppb
2015-11-090914980.490 ppb
2015-11-090914950.870 ppb
2015-11-090914962.74 ppb
2015-11-090914971.08 ppb
2015-11-090915020.840 ppb
2015-11-090915040.720 ppb
2015-11-100914940.730 ppb
2015-11-1009149914.5 ppb
2015-11-100915000.520 ppb
2015-11-100915015.39 ppb
2015-11-100915030.400 ppb
2016-02-080915218.21 ppb
2016-02-080915228.83 ppb
2016-02-080915266.08 ppb
2016-02-0809152311.7 ppb
2016-02-080915248.18 ppb
2016-02-0809152510.5 ppb
2016-02-080915275.53 ppb
2016-02-080915285.98 ppb
2016-02-080915295.58 ppb
2016-02-080915307.36 ppb
2016-02-080915314.28 ppb
2016-02-080915326.01 ppb
2016-05-0909155011.8 ppb
2016-05-0909155113.6 ppb
2016-05-0909155212.6 ppb
2016-05-0909155316.1 ppb
2016-05-090915557.00 ppb
2016-05-090915564.43 ppb
2016-05-090915574.17 ppb
2016-05-090915594.02 ppb
2016-05-1009154910.6 ppb
2016-05-100915544.51 ppb
2016-05-100915586.49 ppb
2016-05-100915605.80 ppb
2016-08-080915702.25 ppb
2016-08-080915713.10 ppb
2016-08-080915722.67 ppb
2016-08-080915733.80 ppb
2016-08-080915760.630 ppb
2016-08-0809157813.3 ppb
2016-08-080915791.14 ppb
2016-08-080915806.18 ppb
2016-08-090915691.81 ppb
2016-08-090915741.30 ppb
2016-08-090915752.62 ppb
2016-08-090915771.03 ppb
2016-11-070915970.570 ppb
2016-11-070915980.650 ppb
2016-11-070915991.24 ppb
2016-11-070916000.940 ppb
2016-11-070916027.89 ppb
2016-11-07091603ND
2016-11-070916043.95 ppb
2016-11-07091606ND
2016-11-080915960.600 ppb
2016-11-08091601ND
2016-11-080916050.760 ppb
2016-11-08091607ND
2017-02-06AB9509216.8 ppb
2017-02-06AB9509324.5 ppb
2017-02-06AB9509414.5 ppb
2017-02-06AB9509516.9 ppb
2017-02-06AB950975.31 ppb
2017-02-06AB950989.79 ppb
2017-02-06AB950993.41 ppb
2017-02-06AB951016.82 ppb
2017-02-07AB9509116.1 ppb
2017-02-07AB950969.32 ppb
2017-02-07AB9510016.7 ppb
2017-02-07AB951029.62 ppb
2017-05-08AC0145819.0 ppb
2017-05-08AC0145925.0 ppb
2017-05-08AC0146017.0 ppb
2017-05-08AC0146113.7 ppb
2017-05-08AC014637.74 ppb
2017-05-08AC014645.64 ppb
2017-05-08AC014657.75 ppb
2017-05-08AC014674.02 ppb
2017-05-09AC014579.49 ppb
2017-05-09AC014624.92 ppb
2017-05-09AC014667.77 ppb
2017-05-09AC014686.43 ppb
2017-08-07AC050726.57 ppb
2017-08-07AC050747.41 ppb
2017-08-07AC050756.24 ppb
2017-08-07AC0507722.4 ppb
2017-08-07AC050782.74 ppb
2017-08-07AC0507911.9 ppb
2017-08-07AC050871.77 ppb
2017-08-08AC050715.12 ppb
2017-08-08AC0507310.2 ppb
2017-08-08AC050763.46 ppb
2017-08-08AC050805.06 ppb
2017-08-08AC050822.92 ppb
2017-11-06AC089932.22 ppb
2017-11-06AC089942.33 ppb
2017-11-06AC089951.84 ppb
2017-11-06AC089961.80 ppb
2017-11-06AC0899821.3 ppb
2017-11-06AC089991.74 ppb
2017-11-06AC0900011.2 ppb
2017-11-06AC090021.85 ppb
2017-11-07AC089921.46 ppb
2017-11-07AC089970.920 ppb
2017-11-07AC090012.09 ppb
2017-11-07AC090031.19 ppb
2018-02-05AC1509130.2 ppb
2018-02-05AC1509237.6 ppb
2018-02-05AC1509323.4 ppb
2018-02-05AC1509428.0 ppb
2018-02-05AC150965.82 ppb
2018-02-05AC1509719.9 ppb
2018-02-05AC150983.83 ppb
2018-02-05AC1510011.7 ppb
2018-02-06AC1509023.2 ppb
2018-02-06AC1509515.3 ppb
2018-02-06AC1509929.3 ppb
2018-02-06AC1510116.9 ppb
2018-05-07AC1931716.9 ppb
2018-05-07AC1931824.4 ppb
2018-05-07AC1931922.4 ppb
2018-05-07AC1932020.5 ppb
2018-05-07AC1932116.7 ppb
2018-05-07AC193228.38 ppb
2018-05-07AC193238.78 ppb
2018-05-07AC193248.49 ppb
2018-05-07AC193258.51 ppb
2018-05-07AC1932615.4 ppb
2018-05-07AC193276.35 ppb
2018-05-07AC193288.97 ppb
2018-06-04AC2176817.9 ppb
2018-06-04AC2177311.4 ppb
2018-06-04AC2177716.7 ppb
2018-06-04AC2177913.7 ppb
2018-06-05AC2177025.5 ppb
2018-06-05AC2177123.8 ppb
2018-06-05AC2177219.7 ppb
2018-06-06AC2176922.8 ppb
2018-06-06AC2177420.0 ppb
2018-06-06AC2177511.0 ppb
2018-06-06AC217768.43 ppb
2018-06-07AC2177810.2 ppb
2018-07-09AC228987.15 ppb
2018-07-10AC2288818.7 ppb
2018-07-10AC2289313.1 ppb
2018-07-10AC2289716.8 ppb
2018-07-10AC2289911.9 ppb
2018-07-11AC2289030.7 ppb
2018-07-11AC2289126.5 ppb
2018-07-11AC2289221.0 ppb
2018-07-12AC2288923.1 ppb
2018-07-12AC2289424.5 ppb
2018-07-12AC2289511.4 ppb
2018-07-12AC228968.20 ppb
2018-08-06AC240905.72 ppb
2018-08-06AC2409114.5 ppb
2018-08-06AC240928.81 ppb
2018-08-06AC240937.64 ppb
2018-08-06AC240945.78 ppb
2018-08-06AC240952.87 ppb
2018-08-06AC2409615.1 ppb
2018-08-06AC240975.49 ppb
2018-08-06AC240985.51 ppb
2018-08-06AC240993.52 ppb
2018-08-06AC241005.42 ppb
2018-08-06AC241012.59 ppb
2018-09-10AC253626.76 ppb
2018-09-10AC253635.44 ppb
2018-09-10AC253645.13 ppb
2018-09-11AC253617.54 ppb
2018-09-11AC2536629.7 ppb
2018-09-11AC253671.65 ppb
2018-09-11AC2536814.3 ppb
2018-09-12AC253700.697 ppb
2018-09-13AC253604.11 ppb
2018-09-13AC253651.02 ppb
2018-09-13AC253692.89 ppb
2018-09-13AC253711.43 ppb
2018-10-08AC2682911.2 ppb
2018-10-08AC268305.39 ppb
2018-10-08AC268314.18 ppb
2018-10-09AC268371.23 ppb
2018-10-10AC268288.25 ppb
2018-10-10AC2683312.3 ppb
2018-10-10AC268342.89 ppb
2018-10-10AC2683510.6 ppb
2018-10-11AC268278.40 ppb
2018-10-11AC268322.44 ppb
2018-10-11AC268364.29 ppb
2018-10-11AC268382.50 ppb
2018-11-05AC2801002.54 ppb
2018-11-05AC280894.48 ppb
2018-11-05AC280904.43 ppb
2018-11-05AC2809122.1 ppb
2018-11-05AC280925.12 ppb
2018-11-05AC280937.05 ppb
2018-11-05AC280942.00 ppb
2018-11-05AC2809526.5 ppb
2018-11-05AC280962.95 ppb
2018-11-05AC2809713.1 ppb
2018-11-05AC280983.25 ppb
2018-11-05AC280991.69 ppb
2018-12-03AC2914312.6 ppb
2018-12-03AC291485.89 ppb
2018-12-03AC291528.24 ppb
2018-12-03AC291546.03 ppb
2018-12-04AC2914414.9 ppb
2018-12-04AC2914920.8 ppb
2018-12-04AC291508.44 ppb
2018-12-04AC2915110.2 ppb
2018-12-05AC2914516.0 ppb
2018-12-05AC2914611.5 ppb
2018-12-05AC2914714.2 ppb
2018-12-06AC291535.24 ppb
2019-01-07AC3065219.1 ppb
2019-01-07AC3065312.9 ppb
2019-01-07AC3065416.7 ppb
2019-01-08AC3065115.2 ppb
2019-01-08AC3065628.8 ppb
2019-01-08AC306579.97 ppb
2019-01-08AC306588.52 ppb
2019-01-09AC306605.20 ppb
2019-01-10AC3065015.5 ppb
2019-01-10AC306559.82 ppb
2019-01-10AC3065910.3 ppb
2019-01-10AC3066113.4 ppb
2019-02-04AC318589.02 ppb
2019-02-04AC318595.08 ppb
2019-02-04AC318609.05 ppb
2019-02-04AC318617.46 ppb
2019-02-04AC318628.41 ppb
2019-02-04AC318634.46 ppb
2019-02-04AC318646.34 ppb
2019-02-04AC318654.88 ppb
2019-02-04AC318665.56 ppb
2019-02-04AC318676.46 ppb
2019-02-04AC318683.47 ppb
2019-02-04AC318695.29 ppb
2019-03-05AC3290813.2 ppb
2019-03-05AC329098.93 ppb
2019-03-05AC3291015.0 ppb
2019-03-05AC3291112.2 ppb
2019-03-05AC3291215.0 ppb
2019-03-05AC329136.01 ppb
2019-03-05AC3291414.1 ppb
2019-03-05AC329157.75 ppb
2019-03-05AC329166.02 ppb
2019-03-05AC329179.38 ppb
2019-03-05AC329184.25 ppb
2019-03-05AC329196.60 ppb
2019-04-10AC3452915.6 ppb
2019-04-10AC345346.44 ppb
2019-04-10AC3453811.2 ppb
2019-04-10AC345408.27 ppb
2019-04-11AC3453116.2 ppb
2019-04-11AC3453212.7 ppb
2019-04-11AC3453317.2 ppb
2019-04-12AC3453021.8 ppb
2019-04-12AC3453526.4 ppb
2019-04-12AC3453621.8 ppb
2019-04-12AC3453711.1 ppb
2019-04-12AC345395.98 ppb
2019-05-13AC3607721.4 ppb
2019-05-13AC3607823.6 ppb
2019-05-13AC3607927.6 ppb
2019-05-13AC3608020.7 ppb
2019-05-13AC3608121.8 ppb
2019-05-13AC3608213.3 ppb
2019-05-13AC3608332.9 ppb
2019-05-13AC3608416.0 ppb
2019-05-13AC3608518.6 ppb
2019-05-13AC3608621.7 ppb
2019-05-13AC3608710.6 ppb
2019-05-13AC3608816.6 ppb
2019-06-03AC3690812.0 ppb
2019-06-03AC369098.93 ppb
2019-06-03AC369135.59 ppb
2019-06-03AC3691424.1 ppb
2019-06-03AC369157.57 ppb
2019-06-03AC3691610.4 ppb
2019-06-03AC3691716.3 ppb
2019-06-03AC369184.26 ppb
2019-06-03AC369198.51 ppb
2019-06-04AC3691018.7 ppb
2019-06-04AC3691115.7 ppb
2019-06-04AC3691218.4 ppb
2019-07-08AC3846421.6 ppb
2019-07-08AC3846828.2 ppb
2019-07-08AC3847020.2 ppb
2019-07-08AC3847124.1 ppb
2019-07-09AC3846031.5 ppb
2019-07-09AC3846132.5 ppb
2019-07-09AC3846231.0 ppb
2019-07-09AC3846335.0 ppb
2019-07-09AC3846535.5 ppb
2019-07-09AC3846627.0 ppb
2019-07-09AC3846719.7 ppb
2019-07-09AC3846912.3 ppb
2019-08-06AC3949011.1 ppb
2019-08-06AC3949118.4 ppb
2019-08-06AC3949218.9 ppb
2019-08-06AC3949316.7 ppb
2019-08-06AC3949418.6 ppb
2019-08-06AC3949634.0 ppb
2019-08-06AC3949710.1 ppb
2019-08-06AC394989.73 ppb
2019-08-06AC394999.73 ppb
2019-08-06AC395003.25 ppb
2019-08-06AC395016.07 ppb
2019-08-06AC400127.39 ppb
2019-09-10AC412425.66 ppb
2019-09-10AC4124312.7 ppb
2019-09-10AC412449.48 ppb
2019-09-10AC412457.63 ppb
2019-09-10AC412469.26 ppb
2019-09-10AC4124815.8 ppb
2019-09-10AC412495.95 ppb
2019-09-10AC4125013.2 ppb
2019-09-10AC412515.17 ppb
2019-09-10AC412521.60 ppb
2019-09-10AC412532.65 ppb
2019-09-10AC412682.27 ppb
2019-10-07AC425013.82 ppb
2019-10-07AC425023.64 ppb
2019-10-07AC425033.25 ppb
2019-10-07AC425042.86 ppb
2019-10-07AC425053.61 ppb
2019-10-07AC425061.05 ppb
2019-10-07AC4250712.1 ppb
2019-10-07AC425082.09 ppb
2019-10-07AC4250910.2 ppb
2019-10-07AC425102.62 ppb
2019-10-07AC425110.710 ppb
2019-10-07AC425121.32 ppb