Chromium (total)
Rancho Ynecita Mutual Water Company
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 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | 4.67 ppb | 3 | 1 | ND - 14.0 ppb |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | 11.4 ppb | 6 | 6 | 7.10 ppb - 16.0 ppb |
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 |
|---|---|---|
| 2020-04-21 | CA4200837_003_003-202004210800 | ND |
| 2020-04-21 | CA4200837_001_001-202004210930 | 14.0 ppb |
| 2020-04-21 | CA4200837_004_004-202004210845 | ND |
| 2023-06-21 | CA4200837_001_001-202306210805 | 7.20 ppb |
| 2023-06-21 | CA4200837_003_003-202306210710 | 7.10 ppb |
| 2023-12-26 | CA4200837_001_001-202312261310 | 14.0 ppb |
| 2023-12-26 | CA4200837_001_001-202312261340 | 14.0 ppb |
| 2023-12-26 | CA4200837_003_003-202312261425 | 16.0 ppb |
| 2023-12-26 | CA4200837_004_004-202312261310 | 10.00 ppb |