Chloroform
Fond Du Lac Waterworks
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 0.126 ppb | 19 | 7 | ND - 0.510 ppb |
| 2015 | 0.193 ppb | 21 | 14 | ND - 0.430 ppb |
| 2016 | 0.233 ppb | 18 | 10 | ND - 1.10 ppb |
| 2017 | 0.349 ppb | 21 | 17 | ND - 0.810 ppb |
| 2018 | 0.230 ppb | 23 | 11 | ND - 0.820 ppb |
| 2019 | 0.313 ppb | 18 | 9 | ND - 1.20 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 |
|---|---|---|
| 2014-02-17 | 770785 | ND |
| 2014-02-17 | 770783 | 0.230 ppb |
| 2014-02-18 | 771007 | ND |
| 2014-02-18 | 771010 | ND |
| 2014-04-14 | 780745 | ND |
| 2014-05-14 | 785684 | ND |
| 2014-05-14 | 785685 | ND |
| 2014-05-14 | 785686 | ND |
| 2014-05-14 | 785687 | ND |
| 2014-07-21 | 804444 | ND |
| 2014-08-12 | 809931 | ND |
| 2014-08-12 | 809928 | 0.250 ppb |
| 2014-08-12 | 809930 | 0.360 ppb |
| 2014-08-12 | 809929 | 0.400 ppb |
| 2014-10-29 | 828515 | ND |
| 2014-11-11 | 830917 | ND |
| 2014-11-11 | 830915 | 0.300 ppb |
| 2014-11-11 | 830916 | 0.340 ppb |
| 2014-11-11 | 830914 | 0.510 ppb |
| 2015-02-03 | 841710 | ND |
| 2015-02-03 | 841707 | 0.170 ppb |
| 2015-02-16 | 843832 | ND |
| 2015-02-16 | 843830 | 0.270 ppb |
| 2015-02-16 | 843831 | 0.360 ppb |
| 2015-02-16 | 843829 | 0.400 ppb |
| 2015-04-21 | 855442 | ND |
| 2015-05-18 | 860211 | ND |
| 2015-05-18 | 860209 | 0.260 ppb |
| 2015-05-18 | 860210 | 0.280 ppb |
| 2015-05-18 | 860208 | 0.430 ppb |
| 2015-07-20 | 871829 | ND |
| 2015-08-17 | 877448 | 0.180 ppb |
| 2015-08-17 | 877447 | 0.240 ppb |
| 2015-08-17 | 877446 | 0.270 ppb |
| 2015-08-17 | 877445 | 0.410 ppb |
| 2015-10-27 | 891260 | ND |
| 2015-11-11 | 893801 | ND |
| 2015-11-11 | 893800 | 0.220 ppb |
| 2015-11-11 | 893799 | 0.270 ppb |
| 2015-11-11 | 893798 | 0.300 ppb |
| 2016-01-22 | 902600 | 1.10 ppb |
| 2016-02-15 | 905422 | 0.260 ppb |
| 2016-02-15 | 905420 | 0.310 ppb |
| 2016-02-15 | 905421 | 0.350 ppb |
| 2016-02-15 | 905419 | 0.450 ppb |
| 2016-03-08 | 908868 | ND |
| 2016-03-08 | 908871 | ND |
| 2016-04-06 | 914177 | ND |
| 2016-08-15 | 939250 | ND |
| 2016-08-15 | 939248 | ND |
| 2016-08-15 | 939249 | 0.300 ppb |
| 2016-08-15 | 939247 | 0.380 ppb |
| 2016-09-26 | 948632 | ND |
| 2016-11-14 | 958942 | ND |
| 2016-11-14 | 958940 | 0.270 ppb |
| 2016-11-14 | 958941 | 0.290 ppb |
| 2016-11-14 | 958939 | 0.480 ppb |
| 2016-11-28 | 961245 | ND |
| 2017-02-13 | 973446 | ND |
| 2017-02-13 | 973445 | 0.280 ppb |
| 2017-02-13 | 973444 | 0.300 ppb |
| 2017-02-13 | 973443 | 0.310 ppb |
| 2017-02-14 | 973636 | ND |
| 2017-03-06 | 976159 | ND |
| 2017-04-24 | 985200 | 0.330 ppb |
| 2017-05-15 | 990472 | 0.270 ppb |
| 2017-05-15 | 990469 | 0.600 ppb |
| 2017-05-15 | 990471 | 0.620 ppb |
| 2017-05-15 | 990470 | 0.810 ppb |
| 2017-07-26 | 1006861 | ND |
| 2017-08-16 | 1011999 | 0.480 ppb |
| 2017-08-16 | 1011997 | 0.500 ppb |
| 2017-08-16 | 1011998 | 0.500 ppb |
| 2017-08-16 | 1012000 | 0.590 ppb |
| 2017-10-09 | 1023185 | 0.480 ppb |
| 2017-11-13 | 1029593 | 0.260 ppb |
| 2017-11-13 | 1029592 | 0.320 ppb |
| 2017-11-13 | 1029590 | 0.320 ppb |
| 2017-11-13 | 1029591 | 0.360 ppb |
| 2018-02-13 | 1040803 | ND |
| 2018-02-13 | 1040802 | 0.320 ppb |
| 2018-02-13 | 1040800 | 0.430 ppb |
| 2018-02-13 | 1040801 | 0.720 ppb |
| 2018-02-21 | 1042067 | ND |
| 2018-02-21 | 1042069 | ND |
| 2018-02-21 | 1042065 | 0.300 ppb |
| 2018-04-11 | 1049883 | ND |
| 2018-04-11 | 1049881 | ND |
| 2018-05-14 | 1055389 | ND |
| 2018-05-14 | 1055386 | 0.320 ppb |
| 2018-05-14 | 1055388 | 0.430 ppb |
| 2018-05-14 | 1055387 | 0.460 ppb |
| 2018-08-13 | 1073422 | ND |
| 2018-08-13 | 1073425 | ND |
| 2018-08-13 | 1073424 | 0.570 ppb |
| 2018-08-13 | 1073423 | 0.820 ppb |
| 2018-08-15 | 1074183 | ND |
| 2018-08-15 | 1074181 | ND |
| 2018-11-12 | 1092410 | ND |
| 2018-11-12 | 1092413 | ND |
| 2018-11-12 | 1092412 | 0.390 ppb |
| 2018-11-12 | 1092411 | 0.520 ppb |
| 2019-02-18 | 1105566 | ND |
| 2019-02-18 | 1105569 | ND |
| 2019-02-18 | 1105568 | 0.410 ppb |
| 2019-02-18 | 1105567 | 0.820 ppb |
| 2019-03-06 | 1108269 | ND |
| 2019-03-06 | 1108265 | 0.280 ppb |
| 2019-05-14 | 1121045 | ND |
| 2019-05-14 | 1121046 | ND |
| 2019-05-14 | 1121048 | 0.750 ppb |
| 2019-05-14 | 1121047 | 0.780 ppb |
| 2019-08-12 | 1140153 | ND |
| 2019-08-12 | 1140150 | 0.290 ppb |
| 2019-08-12 | 1140152 | 0.490 ppb |
| 2019-08-12 | 1140151 | 1.20 ppb |
| 2019-11-11 | 1160250 | ND |
| 2019-11-11 | 1160248 | ND |
| 2019-11-11 | 1160247 | ND |
| 2019-11-11 | 1160249 | 0.620 ppb |