Chloroform
Villages of Bocage- Madisonville
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 |
|---|---|---|---|---|
| 2018 | 0.666 ppb | 16 | 14 | ND - 1.20 ppb |
| 2019 | 0.701 ppb | 16 | 14 | ND - 0.910 ppb |
| 2020 | 0.781 ppb | 8 | 8 | 0.610 ppb - 0.890 ppb |
| 2021 | 0.501 ppb | 8 | 6 | ND - 0.820 ppb |
| 2022 | 0.720 ppb | 8 | 8 | 0.450 ppb - 0.830 ppb |
| 2023 | 6.81 ppb | 8 | 7 | ND - 50.3 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 |
|---|---|---|
| 2018-02-02 | 35371897001 | 1.20 ppb |
| 2018-02-02 | 35371897002 | 0.440 ppb |
| 2018-02-02 | 35371897002 | 0.440 ppb |
| 2018-02-02 | 35371897001 | 1.20 ppb |
| 2018-05-03 | 35390322002 | 0.620 ppb |
| 2018-05-03 | 35390322001 | 0.800 ppb |
| 2018-05-03 | 35390322002 | 0.620 ppb |
| 2018-05-03 | 35390322001 | 0.800 ppb |
| 2018-08-01 | 35408273001 | 1.000 ppb |
| 2018-08-01 | 35408273002 | ND |
| 2018-08-01 | 35408273001 | 1.000 ppb |
| 2018-08-01 | 35408273002 | ND |
| 2018-11-15 | 35432277001 | 0.640 ppb |
| 2018-11-15 | 35432277001 | 0.640 ppb |
| 2018-11-15 | 35432277002 | 0.630 ppb |
| 2018-11-15 | 35432277002 | 0.630 ppb |
| 2019-02-21 | 35450029001 | 0.760 ppb |
| 2019-02-21 | 35450029002 | 0.720 ppb |
| 2019-02-21 | 35450029001 | 0.760 ppb |
| 2019-02-21 | 35450029002 | 0.720 ppb |
| 2019-05-08 | 35468294001 | 0.690 ppb |
| 2019-05-08 | 35468294002 | ND |
| 2019-05-08 | 35468294001 | 0.690 ppb |
| 2019-05-08 | 35468294002 | ND |
| 2019-08-07 | 35488454002 | 0.840 ppb |
| 2019-08-07 | 35488454001 | 0.840 ppb |
| 2019-08-07 | 35488454001 | 0.840 ppb |
| 2019-08-07 | 35488454002 | 0.840 ppb |
| 2019-11-15 | 35512871001 | 0.910 ppb |
| 2019-11-15 | 35512871002 | 0.850 ppb |
| 2019-11-15 | 35512871002 | 0.850 ppb |
| 2019-11-15 | 35512871001 | 0.910 ppb |
| 2020-02-07 | 35529509002 | 0.890 ppb |
| 2020-02-07 | 35529509001 | 0.880 ppb |
| 2020-05-08 | 35548829001 | 0.610 ppb |
| 2020-05-08 | 35548829002 | 0.680 ppb |
| 2020-08-13 | 35570704001 | 0.830 ppb |
| 2020-08-13 | 35570704002 | 0.860 ppb |
| 2020-11-06 | 35590520001 | 0.750 ppb |
| 2020-11-06 | 35590520002 | 0.750 ppb |
| 2021-02-05 | 35610009001 | 0.660 ppb |
| 2021-02-05 | 35610009002 | 0.730 ppb |
| 2021-05-07 | 35631657001 | ND |
| 2021-05-07 | 35631657002 | 0.400 ppb |
| 2021-08-06 | 35653787001 | 0.820 ppb |
| 2021-08-06 | 35653787002 | 0.810 ppb |
| 2021-11-05 | 35676310001 | 0.590 ppb |
| 2021-11-05 | 35676310002 | ND |
| 2022-02-11 | 35696585002 | 0.450 ppb |
| 2022-02-11 | 35696585001 | 0.490 ppb |
| 2022-05-06 | 35715929002 | 0.780 ppb |
| 2022-05-06 | 35715929001 | 0.820 ppb |
| 2022-08-03 | 35737001009 | 0.790 ppb |
| 2022-08-03 | 35737001010 | 0.820 ppb |
| 2022-11-04 | 35758185001 | 0.780 ppb |
| 2022-11-04 | 35758185002 | 0.830 ppb |
| 2023-02-03 | 35776978001 | 0.570 ppb |
| 2023-02-03 | 35776978002 | 0.650 ppb |
| 2023-05-05 | 35797780001 | 0.820 ppb |
| 2023-05-05 | 35797780002 | 0.890 ppb |
| 2023-08-04 | 35818388001 | 0.640 ppb |
| 2023-08-04 | 35818388002 | 0.570 ppb |
| 2023-11-03 | 35839347001 | ND |
| 2023-11-03 | 35839347002 | 50.3 ppb |