Diquat
San Diego County Water Authority
Diquat is a herbicide used on potato crops and aquatic weeds.
23
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 | 4 | 0 | ND |
| 2015 | ND | 4 | 0 | ND |
| 2016 | ND | 4 | 0 | ND |
| 2017 | ND | 4 | 0 | ND |
| 2018 | ND | 4 | 0 | ND |
| 2019 | ND | 3 | 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 |
|---|---|---|
| 2014-02-05 | 9590-003-1053 | ND |
| 2014-04-09 | 9590-003-1340 | ND |
| 2014-07-24 | 9590-003-1216 | ND |
| 2014-12-16 | 9590-003-1100 | ND |
| 2015-01-05 | 9590-003-1007 | ND |
| 2015-04-08 | 9590-003-1415 | ND |
| 2015-08-25 | 9590-003-1310 | ND |
| 2015-10-20 | 9590-003-1149 | ND |
| 2016-02-10 | 9590-003-1320 | ND |
| 2016-06-16 | 9590-003-1405 | ND |
| 2016-08-02 | 9590-003-1105 | ND |
| 2016-11-29 | 9590-003-1322 | ND |
| 2017-03-14 | 9590-003-1417 | ND |
| 2017-06-14 | 9590-003-0916 | ND |
| 2017-07-05 | 9590-003-1148 | ND |
| 2017-10-16 | 9590-003-1253 | ND |
| 2018-01-03 | 9590-003-1208 | ND |
| 2018-04-10 | 9590-003-1206 | ND |
| 2018-09-17 | 9590-003-1256 | ND |
| 2018-10-01 | 9590-003-1302 | ND |
| 2019-06-13 | 9590-003-1003 | ND |
| 2019-09-17 | 9590-003-1250 | ND |
| 2019-12-11 | 9590-003-0807 | ND |