Chromium (total)
Mustang Valley Water Supply Corporation
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 | 0.420 ppb | 5 | 2 | ND - 1.10 ppb |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | N/A | 0 | 0 | N/A |
| 2021 | 3.38 ppb | 5 | 5 | 2.20 ppb - 3.90 ppb |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | N/A | 0 | 0 | N/A |
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 |
|---|---|---|
| 2018-02-20 | Q1806881004 | ND |
| 2018-11-28 | Q1848373010 | ND |
| 2018-11-28 | Q1848373011 | 1.10 ppb |
| 2018-11-28 | Q1848373012 | 1.000 ppb |
| 2018-11-28 | Q1848373013 | ND |
| 2021-07-28 | Q2119759003 | 3.90 ppb |
| 2021-07-28 | Q2119759004 | 2.20 ppb |
| 2021-07-28 | Q2119759005 | 3.80 ppb |
| 2021-07-28 | Q2119759014 | 3.80 ppb |
| 2021-07-28 | Q2119759015 | 3.20 ppb |