Diquat
Purcell
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 | ND | 2 | 0 | ND |
| 2019 | ND | 3 | 0 | ND |
| 2020 | ND | 2 | 0 | ND |
| 2021 | ND | 2 | 0 | ND |
| 2022 | ND | 2 | 0 | ND |
| 2023 | ND | 4 | 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 |
|---|---|---|
| 2018-08-14 | AH14157-01 | ND |
| 2018-10-16 | AJ16112-01 | ND |
| 2019-01-14 | BA14043-01 | ND |
| 2019-04-08 | BD08052-01 | ND |
| 2019-08-13 | BH13107-01 | ND |
| 2020-01-28 | CA28074-01 | ND |
| 2020-04-21 | CD21100-01 | ND |
| 2021-01-19 | DA19096-01 | ND |
| 2021-06-08 | DF08176-01 | ND |
| 2022-06-14 | EF14181-01 | ND |
| 2022-11-15 | EK15124-01 | ND |
| 2023-06-06 | FF06135-01 | ND |
| 2023-08-15 | FH15158-01 | ND |
| 2023-10-17 | FJ17136-01 | ND |
| 2023-12-05 | FL05129-01 | ND |