Diquat
Dayton Valley Water System
Diquat is a herbicide used on potato crops and aquatic weeds.
13
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 | ND | 2 | 0 | ND |
| 2015 | ND | 1 | 0 | ND |
| 2016 | ND | 5 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 1 | 0 | ND |
| 2019 | ND | 4 | 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 |
|---|---|---|
| 2014-05-13 | 201405140421 | ND |
| 2014-05-13 | 201405140422 | ND |
| 2015-05-11 | 201505130156 | ND |
| 2016-05-18 | 201605240207 | ND |
| 2016-06-28 | 6F30029-01 | ND |
| 2016-06-28 | 6F30035-01 | ND |
| 2016-11-09 | 201611110580 | ND |
| 2016-11-09 | 201611110581 | ND |
| 2018-04-05 | 201804060643 | ND |
| 2019-05-20 | 201905240032 | ND |
| 2019-07-24 | 201907260187 | ND |
| 2019-07-24 | 201907260188 | ND |
| 2019-08-14 | 201908160801 | ND |