Diquat
Covington County Water Authority
Diquat is a herbicide used on potato crops and aquatic weeds.
24
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 | 2 | 0 | ND |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | ND | 10 | 0 | ND |
| 2017 | ND | 2 | 0 | ND |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 10 | 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 |
|---|---|---|
| 2014-01-06 | 140107004-1 | ND |
| 2014-04-07 | 140408064-1 | ND |
| 2016-01-04 | 160105030-2 | ND |
| 2016-01-04 | 160105030-1 | ND |
| 2016-01-04 | 160105030-3 | ND |
| 2016-01-04 | 160105030-4 | ND |
| 2016-01-04 | 160105030-5 | ND |
| 2016-04-04 | 160405094-4 | ND |
| 2016-04-04 | 160405094-2 | ND |
| 2016-04-04 | 160405094-5 | ND |
| 2016-04-04 | 160405094-1 | ND |
| 2016-04-04 | 160405094-3 | ND |
| 2017-01-05 | 170109016-1 | ND |
| 2017-04-03 | 170405080-1 | ND |
| 2019-01-07 | 19010197-005H | ND |
| 2019-01-07 | 19010197-001H | ND |
| 2019-01-07 | 19010197-002H | ND |
| 2019-01-07 | 19010197-003H | ND |
| 2019-01-07 | 19010197-004H | ND |
| 2019-04-01 | 19040053-003H | ND |
| 2019-04-01 | 19040053-005H | ND |
| 2019-04-01 | 19040053-004H | ND |
| 2019-04-01 | 19040053-002H | ND |
| 2019-04-01 | 19040053-001H | ND |