Chloroform
CTWC - Naugatuck Region-Central 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.
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 | 24.5 ppb | 20 | 17 | ND - 42.0 ppb |
| 2019 | 23.4 ppb | 17 | 17 | 5.60 ppb - 33.0 ppb |
| 2020 | 20.4 ppb | 17 | 17 | 4.00 ppb - 46.4 ppb |
| 2021 | 20.0 ppb | 17 | 17 | 3.60 ppb - 34.8 ppb |
| 2022 | 21.4 ppb | 17 | 17 | 5.40 ppb - 42.0 ppb |
| 2023 | 19.2 ppb | 17 | 17 | 2.60 ppb - 37.0 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 |
|---|---|---|
| 2018-01-15 | BZ72858VOC1 | 10.00 ppb |
| 2018-02-13 | BZ88506VOC1 | ND |
| 2018-02-14 | BZ89697TTHM | 24.0 ppb |
| 2018-02-14 | BZ89698TTHM | 37.0 ppb |
| 2018-02-14 | BZ89699TTHM | 36.0 ppb |
| 2018-02-14 | BZ89700TTHM | 42.0 ppb |
| 2018-05-21 | CA50437TTHM | 27.0 ppb |
| 2018-05-21 | CA50438TTHM | 15.0 ppb |
| 2018-05-21 | CA50439TTHM | 30.0 ppb |
| 2018-05-21 | CA50440TTHM | 29.0 ppb |
| 2018-05-21 | CA50441VOC1 | ND |
| 2018-06-11 | CA67845VOC1 | ND |
| 2018-08-20 | CB14939 | 20.0 ppb |
| 2018-08-20 | CB14940 | 32.0 ppb |
| 2018-08-20 | CB14941 | 32.0 ppb |
| 2018-08-20 | CB14942 | 32.0 ppb |
| 2018-11-20 | DBP 200513502 | 33.1 ppb |
| 2018-11-20 | DBP 200513504 | 34.5 ppb |
| 2018-11-20 | DBP 200513506 | 19.7 ppb |
| 2018-11-20 | DBP 200513534 | 36.3 ppb |
| 2019-02-12 | VOC1 200521378 | 5.60 ppb |
| 2019-02-20 | DBP 200522447 | 29.4 ppb |
| 2019-02-20 | DBP 200522448 | 25.5 ppb |
| 2019-02-20 | DBP 200522449 | 29.7 ppb |
| 2019-02-20 | DBP 200522450 | 16.7 ppb |
| 2019-05-21 | DBP 200533257 | 25.0 ppb |
| 2019-05-21 | DBP 200533258 | 19.2 ppb |
| 2019-05-21 | DBP 200533259 | 25.7 ppb |
| 2019-05-21 | DBP 200533260 | 6.40 ppb |
| 2019-08-20 | DBP 200545890 | 32.9 ppb |
| 2019-08-20 | DBP 200545891 | 30.4 ppb |
| 2019-08-20 | DBP 200545892 | 28.5 ppb |
| 2019-08-20 | DBP 200545893 | 13.8 ppb |
| 2019-11-19 | DBP 200557404 | 33.0 ppb |
| 2019-11-19 | DBP 200557405 | 32.2 ppb |
| 2019-11-19 | DBP 200557406 | 32.1 ppb |
| 2019-11-19 | DBP 200557407 | 12.5 ppb |
| 2020-01-14 | VOC1 200563046 | 4.00 ppb |
| 2020-02-19 | DBP 200566880 | 23.6 ppb |
| 2020-02-19 | DBP 200566881 | 20.1 ppb |
| 2020-02-19 | DBP 200566882 | 26.9 ppb |
| 2020-02-19 | DBP 200566883 | 8.20 ppb |
| 2020-05-05 | DBP 200574627 | 14.9 ppb |
| 2020-05-05 | DBP 200574628 | 17.5 ppb |
| 2020-05-05 | DBP 200574629 | 9.90 ppb |
| 2020-05-05 | DBP 200574630 | 29.8 ppb |
| 2020-08-14 | DBP 200586717 | 46.4 ppb |
| 2020-08-14 | DBP 200586721 | 32.7 ppb |
| 2020-08-14 | DBP 200586722 | 18.3 ppb |
| 2020-08-14 | DBP 200586723 | 40.7 ppb |
| 2020-11-17 | DBP 200598529 | 14.0 ppb |
| 2020-11-17 | DBP 200598530 | 12.6 ppb |
| 2020-11-17 | DBP 200598531 | 4.30 ppb |
| 2020-11-17 | DBP 200598532 | 23.3 ppb |
| 2021-02-17 | DBP 200607088 | 8.40 ppb |
| 2021-02-17 | DBP 200607089 | 8.00 ppb |
| 2021-02-17 | DBP 200607090 | 3.60 ppb |
| 2021-02-17 | DBP 200607091 | 16.0 ppb |
| 2021-04-06 | VOC1 200611963 | 3.60 ppb |
| 2021-05-21 | DBP 200618173 | 25.8 ppb |
| 2021-05-21 | DBP 200618174 | 18.2 ppb |
| 2021-05-21 | DBP 200618175 | 11.3 ppb |
| 2021-05-21 | DBP 200618176 | 30.7 ppb |
| 2021-08-12 | DBP 200628919 | 27.7 ppb |
| 2021-08-12 | DBP 200628920 | 26.6 ppb |
| 2021-08-12 | DBP 200628921 | 13.4 ppb |
| 2021-08-12 | DBP 200628922 | 34.8 ppb |
| 2021-11-02 | D300094265 300094270 | 31.5 ppb |
| 2021-11-02 | D300094266 300094272 | 29.9 ppb |
| 2021-11-02 | D300094267 300094274 | 16.0 ppb |
| 2021-11-02 | D300094268 300094276 | 33.7 ppb |
| 2022-02-14 | CK66671 | 5.40 ppb |
| 2022-02-22 | CK73058 | 22.0 ppb |
| 2022-02-22 | CK73059 | 18.0 ppb |
| 2022-02-22 | CK73060 | 28.0 ppb |
| 2022-02-22 | CK73061 | 14.0 ppb |
| 2022-05-20 | CL36073 | 19.0 ppb |
| 2022-05-20 | CL36074 | 19.0 ppb |
| 2022-05-20 | CL36075 | 29.0 ppb |
| 2022-05-20 | CL36076 | 13.0 ppb |
| 2022-08-03 | CL96380 | 42.0 ppb |
| 2022-08-03 | CL96381 | 36.0 ppb |
| 2022-08-03 | CL96382 | 41.0 ppb |
| 2022-08-03 | CL96383 | 23.0 ppb |
| 2022-11-04 | CM79285 | 18.0 ppb |
| 2022-11-04 | CM79286 | 12.0 ppb |
| 2022-11-04 | CM79287 | 18.0 ppb |
| 2022-11-04 | CM79288 | 6.90 ppb |
| 2023-01-16 | CN24827 | 2.60 ppb |
| 2023-02-09 | CN41441 | 12.0 ppb |
| 2023-02-09 | CN41442 | 9.40 ppb |
| 2023-02-09 | CN41443 | 16.0 ppb |
| 2023-02-09 | CN41444 | 7.30 ppb |
| 2023-05-08 | CO01644 | 19.0 ppb |
| 2023-05-08 | CO01645 | 16.0 ppb |
| 2023-05-08 | CO01646 | 23.0 ppb |
| 2023-05-08 | CO01647 | 10.00 ppb |
| 2023-08-04 | CO68170 | 37.0 ppb |
| 2023-08-04 | CO68171 | 27.0 ppb |
| 2023-08-04 | CO68172 | 31.0 ppb |
| 2023-08-04 | CO68173 | 16.0 ppb |
| 2023-11-03 | CP41463 | 30.0 ppb |
| 2023-11-03 | CP41464 | 23.0 ppb |
| 2023-11-03 | CP41465 | 29.0 ppb |
| 2023-11-03 | CP41466 | 18.0 ppb |