Diquat
Water Works District #1 of Vermilion
Diquat is a herbicide used on potato crops and aquatic weeds.
15
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 |
|---|---|---|---|---|
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 6 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | ND | 1 | 0 | ND |
| 2023 | ND | 6 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
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 |
|---|---|---|
| 2019-06-10 | 35474976001 | ND |
| 2019-06-10 | 35474976001 | ND |
| 2020-06-10 | 35556215001 | ND |
| 2020-06-10 | 35556215002 | ND |
| 2020-06-10 | 35556215003 | ND |
| 2020-06-10 | 35556215004 | ND |
| 2020-10-05 | 35583034001 | ND |
| 2020-10-05 | 35583034002 | ND |
| 2022-07-25 | 35735487001 | ND |
| 2023-03-27 | 35788777001 | ND |
| 2023-03-27 | 35788777002 | ND |
| 2023-03-27 | 35788779001 | ND |
| 2023-03-27 | 35788779002 | ND |
| 2023-07-10 | 35812353001 | ND |
| 2023-07-10 | 35812353002 | ND |