Diquat
Ephrata Area Joint Authority
Diquat is a herbicide used on potato crops and aquatic weeds.
16
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 | N/A | 0 | 0 | N/A |
| 2020 | ND | 8 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | ND | 8 | 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 |
|---|---|---|
| 2020-04-06 | 22168911.00 | ND |
| 2020-04-13 | 22169077.00 | ND |
| 2020-04-13 | 22169078.00 | ND |
| 2020-04-16 | 22365693.00 | ND |
| 2020-07-13 | 22754007.00 | ND |
| 2020-07-13 | 22754008.00 | ND |
| 2020-07-14 | 22754068.00 | ND |
| 2020-07-17 | 22952569.00 | ND |
| 2023-04-14 | 29056927.00 | ND |
| 2023-04-14 | 29057126.00 | ND |
| 2023-04-14 | 29056929.00 | ND |
| 2023-04-14 | 29056928.00 | ND |
| 2023-07-11 | 29654724.00 | ND |
| 2023-07-18 | 29654891.00 | ND |
| 2023-08-09 | 29844084.00 | ND |
| 2023-08-29 | 29844123.00 | ND |