Diquat
Madison Water Utility
Diquat is a herbicide used on potato crops and aquatic weeds.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | ND | 2 | 0 | ND |
2015 | N/A | 0 | 0 | N/A |
2016 | N/A | 0 | 0 | N/A |
2017 | ND | 21 | 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 |
---|---|---|
2014-02-14 | 770976 | ND |
2014-02-17 | 770978 | ND |
2017-04-19 | 984202 | ND |
2017-04-19 | 984203 | ND |
2017-05-02 | 986350 | ND |
2017-05-02 | 986348 | ND |
2017-05-02 | 986351 | ND |
2017-05-02 | 986349 | ND |
2017-05-03 | 986661 | ND |
2017-05-03 | 986662 | ND |
2017-05-16 | 990680 | ND |
2017-05-16 | 990681 | ND |
2017-05-17 | 990989 | ND |
2017-05-17 | 990988 | ND |
2017-05-24 | 993833 | ND |
2017-05-24 | 993832 | ND |
2017-06-13 | 997175 | ND |
2017-06-13 | 997174 | ND |
2017-06-20 | 999080 | ND |
2017-06-20 | 999081 | ND |
2017-07-25 | 1006458 | ND |
2017-07-25 | 1006457 | ND |
2017-08-14 | 1010908 | ND |