Diquat
Castaic Lake Water Agency
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 | 4 | 0 | ND |
2015 | ND | 4 | 0 | ND |
2016 | ND | 3 | 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 |
---|---|---|
2014-07-30 | 9588-006-0930 | ND |
2014-07-30 | 9588-005-0830 | ND |
2014-11-21 | 9588-004-1155 | ND |
2014-11-25 | 9588-005-1345 | ND |
2015-01-14 | 9588-004-1220 | ND |
2015-07-23 | 9590-004-0750 | ND |
2015-07-23 | 9590-006-0940 | ND |
2015-07-23 | 9590-005-0840 | ND |
2016-07-20 | 9590-005-1115 | ND |
2016-07-20 | 9590-006-1215 | ND |
2016-07-20 | 9590-004-1035 | ND |
2017-07-26 | 9590-005-1300 | ND |
2017-07-26 | 9590-006-1405 | ND |
2017-07-26 | 9590-004-1140 | ND |
2017-11-15 | 9590-005-1115 | ND |
2018-07-25 | 9590-005-1310 | ND |
2018-07-25 | 9590-006-1350 | ND |
2018-07-25 | 9590-004-1230 | ND |
2018-10-11 | 9590-004-1010 | ND |
2019-07-31 | 9590-005-1040 | ND |
2019-07-31 | 9590-004-1000 | ND |
2019-07-31 | 9590-006-1125 | ND |