Diquat
Freeport
Diquat is a herbicide used on potato crops and aquatic weeds.
33
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 | 8 | 0 | ND |
| 2015 | ND | 3 | 0 | ND |
| 2016 | ND | 6 | 0 | ND |
| 2017 | ND | 4 | 0 | ND |
| 2018 | ND | 8 | 0 | ND |
| 2019 | ND | 4 | 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 |
|---|---|---|
| 2014-07-14 | 1407868-003-SOCS | ND |
| 2014-07-14 | 1407868-004-SOCS | ND |
| 2014-07-14 | 1407868-001-SOCS | ND |
| 2014-07-14 | 1407868-002-SOCS | ND |
| 2014-09-17 | 1409C69-001-SOCS | ND |
| 2014-09-17 | 1409C69-004-SOCS | ND |
| 2014-09-17 | 1409C69-002-SOCS | ND |
| 2014-09-17 | 1409C69-003-SOCS | ND |
| 2015-11-04 | 1511297-001-SOCS | ND |
| 2015-11-04 | 1511297-002-SOCS | ND |
| 2015-11-04 | 1511297-003-SOCS | ND |
| 2016-07-13 | 1607A37-004 | ND |
| 2016-07-13 | 1607A37-003 | ND |
| 2016-07-13 | 1607A37-001 | ND |
| 2016-07-13 | 1607A37-002 | ND |
| 2016-10-25 | 702919002-SOCS | ND |
| 2016-10-25 | 702919003-SOCS | ND |
| 2017-02-01 | 7010311002 | ND |
| 2017-02-01 | 7010311004 | ND |
| 2017-02-01 | 7010311003 | ND |
| 2017-02-01 | 7010311001 | ND |
| 2018-05-15 | 7051719002-SOCS | ND |
| 2018-05-15 | 7051719001-SOCS | ND |
| 2018-05-15 | 7051719003-SOCS | ND |
| 2018-05-15 | 7051719004-SOCS | ND |
| 2018-07-03 | 7057027004 | ND |
| 2018-07-03 | 7057027003 | ND |
| 2018-07-03 | 7057027002 | ND |
| 2018-07-03 | 7057027001 | ND |
| 2019-06-18 | 7094186002 | ND |
| 2019-06-18 | 7094186004 | ND |
| 2019-06-18 | 7094186001 | ND |
| 2019-06-18 | 7094186003 | ND |