Chromium (hexavalent)
City of Boulder
Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).
16
Samples
0
Samples exceeding legal limit (MCL)
14
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | 0.178 ppb | 14 | 12 | ND - 0.340 ppb |
| 2014 | 0.118 ppb | 2 | 2 | 0.0960 ppb - 0.140 ppb |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 0.02 ppb
The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
ppb = parts per billion
All test results
| Date | Result |
|---|---|
| 2013-02-19 | 0.220 ppb |
| 2013-02-19 | ND |
| 2013-02-19 | ND |
| 2013-02-19 | 0.340 ppb |
| 2013-05-22 | 0.220 ppb |
| 2013-05-22 | 0.0320 ppb |
| 2013-05-22 | 0.300 ppb |
| 2013-05-22 | 0.0320 ppb |
| 2013-08-26 | 0.300 ppb |
| 2013-08-26 | 0.0440 ppb |
| 2013-08-27 | 0.0580 ppb |
| 2013-08-27 | 0.320 ppb |
| 2013-11-19 | 0.320 ppb |
| 2013-11-19 | 0.310 ppb |
| 2014-02-19 | 0.0960 ppb |
| 2014-02-19 | 0.140 ppb |