Diquat
Redlands City
Diquat is a herbicide used on potato crops and aquatic weeds.
20
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 | 1 | 0 | ND |
| 2016 | ND | 1 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 18 | 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 |
|---|---|---|
| 2015-05-21 | 9590-026-1120 | ND |
| 2016-05-12 | 9590-026-0915 | ND |
| 2019-06-20 | 3334-035-0930 | ND |
| 2019-06-27 | 3334-070-1325 | ND |
| 2019-06-27 | 3334-003-0845 | ND |
| 2019-06-27 | 3334-069-0945 | ND |
| 2019-08-19 | 3334-062-0950 | ND |
| 2019-08-19 | 3334-008-1100 | ND |
| 2019-08-21 | 3334-021-1140 | ND |
| 2019-08-22 | 3334-019-1050 | ND |
| 2019-08-27 | 3334-053-1350 | ND |
| 2019-08-27 | 3334-055-0800 | ND |
| 2019-08-27 | 3334-060-1230 | ND |
| 2019-08-28 | 3334-017-1330 | ND |
| 2019-09-10 | 3334-010-0930 | ND |
| 2019-09-17 | 3334-031-0930 | ND |
| 2019-09-19 | 3334-025-0915 | ND |
| 2019-09-19 | 3334-026-1020 | ND |
| 2019-09-30 | 3334-022-0910 | ND |
| 2019-09-30 | 3334-012-1320 | ND |