Chromium (total)
City of Wilsonville
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 | 4 | 0 | ND |
| 2020 | ND | 4 | 0 | ND |
| 2021 | ND | 3 | 0 | ND |
| 2022 | 1.60 ppb | 2 | 1 | ND - 3.20 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 | Lab ID | Result |
|---|---|---|
| 2018-01-10 | 201712040042-I | ND |
| 2018-04-11 | 201803050004-I | ND |
| 2018-07-18 | 201807190944-I | ND |
| 2018-10-10 | 201809030044-I | ND |
| 2019-01-09 | 201812030009-I | ND |
| 2019-04-10 | 201904110241-I | ND |
| 2019-07-10 | 201907110430-I | ND |
| 2019-10-08 | 201910090408-I | ND |
| 2020-01-02 | 202001030119-I | ND |
| 2020-04-15 | 202004160157-I | ND |
| 2020-07-15 | 202007160188-I | ND |
| 2020-10-14 | 202010150105-I | ND |
| 2021-01-06 | 202101070374-I | ND |
| 2021-04-14 | 202104150878-I | ND |
| 2021-07-27 | 202107280247-I | ND |
| 2022-02-02 | 202202030907-I | 3.20 ppb |
| 2022-04-13 | 202204140832-I | ND |
| 2023-01-11 | 380-34174-2-I | ND |