Diquat
Columbus Municipal Utility
Diquat is a herbicide used on potato crops and aquatic weeds.
8
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 | 4 | 0 | ND |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 4 | 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 |
|---|---|---|
| 2015-04-23 | 300620RS28-1502 | ND |
| 2015-04-23 | 300621RS28-1502 | ND |
| 2015-09-02 | 3314502RS28-1503 | ND |
| 2015-09-02 | 3314511RS28-1503 | ND |
| 2018-04-26 | 3921990RS28-1802 | ND |
| 2018-04-26 | 3921999RS28-1802 | ND |
| 2018-09-27 | 4072048RS28-1803 | ND |
| 2018-09-27 | 4072057RS28-1803 | ND |