Diquat
Placer County Water Agency - Foothill
Diquat is a herbicide used on potato crops and aquatic weeds.
9
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | ND | 2 | 0 | ND |
| 2015 | ND | 2 | 0 | ND |
| 2016 | ND | 3 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 2 | 0 | ND |
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
| Date | Lab ID | Result |
|---|---|---|
| 2014-08-20 | 3334-002-1010 | ND |
| 2014-08-20 | 3334-007-1200 | ND |
| 2015-08-11 | 3334-002-1000 | ND |
| 2015-08-11 | 3334-007-1305 | ND |
| 2016-08-03 | 3334-014-1045 | ND |
| 2016-08-17 | 3334-002-1215 | ND |
| 2016-08-17 | 3334-007-0945 | ND |
| 2019-08-27 | 3334-002-0000 | ND |
| 2019-09-09 | 3334-007-1330 | ND |