Diquat
Magnolia Waterworks
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 |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | N/A | 0 | 0 | N/A |
| 2015 | ND | 6 | 0 | ND |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 9 | 0 | ND |
| 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 |
|---|---|---|
| 2015-01-05 | 15008007608 | ND |
| 2015-01-05 | 15008007408 | ND |
| 2015-03-03 | 15065001601 | ND |
| 2015-04-06 | 15099004108 | ND |
| 2015-04-06 | 15099004808 | ND |
| 2015-04-06 | 15099004908 | ND |
| 2018-01-02 | 18004004208 | ND |
| 2018-01-02 | 18004005408 | ND |
| 2018-01-02 | 18004005308 | ND |
| 2018-04-03 | 18095001908 | ND |
| 2018-04-03 | 18095002708 | ND |
| 2018-04-03 | 18095002808 | ND |
| 2018-07-03 | 18186007208 | ND |
| 2018-07-03 | 18186008108 | ND |
| 2018-07-03 | 18186008008 | ND |