Chromium (total)
South Norwalk Electric and Water
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
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 | ND | 2 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 2 | 0 | ND |
| 2021 | ND | 2 | 0 | ND |
| 2022 | ND | 2 | 0 | ND |
| 2023 | ND | 2 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EPA Maximum Contaminant
Level (MCL): 100 ppb
The legal limit for total chromium, established in 1991, was based on a 1958 toxicity study in laboratory animals, and applies to both the less-toxic trivalent chromium and the more-toxic hexavalent chromium forms of this compound. This limit does not protect against the risk of cancer from ingestion of hexavalent chromium.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-05-10 | 18051007C-IOC1 | ND |
| 2018-05-10 | 18051001C-IOCR | ND |
| 2019-05-09 | 19050907C-IOC1 | ND |
| 2019-05-09 | 19050901C-IOCR | ND |
| 2020-05-14 | 20051407C-IOC1 | ND |
| 2020-05-14 | 20051401C-IOCR | ND |
| 2021-05-13 | 21051307C-IOC1 | ND |
| 2021-05-13 | 21051301C-IOCR | ND |
| 2022-05-12 | 22051207C-IOC1 | ND |
| 2022-05-12 | 22051201C-IOCR | ND |
| 2023-05-17 | 23051707C-IOC1 | ND |
| 2023-05-17 | 23051701C-IOCR | ND |