Diquat
City of La Grande
Diquat is a herbicide used on potato crops and aquatic weeds.
20
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 | 10 | 0 | ND |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | ND | 10 | 0 | ND |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
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 |
|---|---|---|
| 2014-04-09 | 1389861-S | ND |
| 2014-04-09 | 1389811-S | ND |
| 2014-04-09 | 1389821-S | ND |
| 2014-04-09 | 1389911-S | ND |
| 2014-04-09 | 1389851-S | ND |
| 2014-07-09 | 1415861-S | ND |
| 2014-07-09 | 1415871-S | ND |
| 2014-07-09 | 1415781-S | ND |
| 2014-07-09 | 1415791-S | ND |
| 2014-07-23 | 1420001-S | ND |
| 2017-04-12 | 1683861-S | ND |
| 2017-04-12 | 1683901-S | ND |
| 2017-04-12 | 1683841-S | ND |
| 2017-04-12 | 1683881-S | ND |
| 2017-04-12 | 1683821-S | ND |
| 2017-07-19 | 1711581-S | ND |
| 2017-07-19 | 1711571-S | ND |
| 2017-07-19 | 1711591-S | ND |
| 2017-07-19 | 1711561-S | ND |
| 2017-09-13 | 1727351-S | ND |