Diquat
Beauregard Water Authority
Diquat is a herbicide used on potato crops and aquatic weeds.
14
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 | N/A | 0 | 0 | N/A |
| 2015 | ND | 3 | 0 | ND |
| 2016 | ND | 4 | 0 | ND |
| 2017 | ND | 2 | 0 | ND |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 5 | 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 |
|---|---|---|
| 2015-04-14 | AB03306 | ND |
| 2015-04-14 | AB03304 | ND |
| 2015-04-14 | AB03305 | ND |
| 2016-01-12 | AB09703 | ND |
| 2016-01-12 | AB09702 | ND |
| 2016-04-13 | AB11108 | ND |
| 2016-04-13 | AB11107 | ND |
| 2017-01-10 | AB17179 | ND |
| 2017-04-11 | AB18595 | ND |
| 2019-01-17 | AB32611 | ND |
| 2019-01-17 | AB32612 | ND |
| 2019-04-10 | AB34079 | ND |
| 2019-10-17 | AB39407 | ND |
| 2019-10-17 | AB39406 | ND |