Diquat
Calam - West Placer
NOTE: Calam - West Placer purchases water from City of Roseville which is required to test for diquat. Sample information shown below was taken by City of Roseville.
Diquat is a herbicide used on potato crops and aquatic weeds.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | N/A | 0 | 0 | N/A |
| 2015 | ND | 2 | 0 | ND |
| 2016 | ND | 3 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 2 | 0 | ND |
| 2019 | N/A | 0 | 0 | N/A |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 6 ppb
The EWG Health Guideline of 6 ppb for diquat 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 cataracts.
EPA Maximum Contaminant
Level (MCL) 20 ppb
The legal limit for diquat, established in 1992, was based on a toxicity study in laboratory animals conducted in the 1980s.
ppb = parts per billion
All test results
NOTE: Calam - West Placer purchases water from City of Roseville which is required to test for diquat. Sample information shown below was taken by City of Roseville.
| Date | Lab ID | Result |
|---|---|---|
| 2015-11-12 | 5810-002-0937 | ND |
| 2016-08-25 | 5810-015-0926 | ND |
| 2016-08-25 | 5810-017-0808 | ND |
| 2016-08-25 | 5810-019-0850 | ND |
| 2018-08-23 | 5810-008-1056 | ND |
| 2018-08-23 | 5810-015-1210 | ND |