Chromium (total)
Mountain Regional Water Special Service District
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 | 4 | 0 | ND |
| 2019 | ND | 12 | 0 | ND |
| 2020 | ND | 2 | 0 | ND |
| 2021 | ND | 1 | 0 | ND |
| 2022 | 0.608 ppb | 12 | 1 | ND - 7.30 ppb |
| 2023 | ND | 1 | 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 | Result |
|---|---|
| 2018-06-06 | ND |
| 2018-06-20 | ND |
| 2018-08-23 | ND |
| 2018-09-05 | ND |
| 2019-01-03 | ND |
| 2019-01-03 | ND |
| 2019-01-03 | ND |
| 2019-01-03 | ND |
| 2019-01-24 | ND |
| 2019-01-24 | ND |
| 2019-01-24 | ND |
| 2019-02-25 | ND |
| 2019-02-25 | ND |
| 2019-02-25 | ND |
| 2019-03-20 | ND |
| 2019-11-14 | ND |
| 2020-07-14 | ND |
| 2020-09-21 | ND |
| 2021-12-08 | ND |
| 2022-02-17 | ND |
| 2022-02-17 | ND |
| 2022-02-17 | 7.30 ppb |
| 2022-02-17 | ND |
| 2022-05-05 | ND |
| 2022-05-05 | ND |
| 2022-05-05 | ND |
| 2022-08-04 | ND |
| 2022-08-04 | ND |
| 2022-08-04 | ND |
| 2022-09-07 | ND |
| 2022-12-07 | ND |
| 2023-12-11 | ND |