Diquat
Carlsbad Municipal Water System
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 | 6 | 0 | ND |
2015 | N/A | 0 | 0 | N/A |
2016 | ND | 2 | 0 | ND |
2017 | ND | 6 | 0 | ND |
2018 | ND | 4 | 0 | ND |
2019 | N/A | 0 | 0 | N/A |
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 |
---|---|---|
2014-01-15 | 1401736-005A | ND |
2014-06-24 | 1406C70-005A | ND |
2014-07-15 | 1407919-001A | ND |
2014-07-15 | 1407920-001A | ND |
2014-10-16 | 1410961-001A | ND |
2014-10-16 | 1410960-001A | ND |
2016-02-09 | 1602465-005A | ND |
2016-04-12 | 1604620-002A | ND |
2017-06-05 | 2017016713 | ND |
2017-06-05 | 2017016711 | ND |
2017-06-05 | 2017016712 | ND |
2017-10-30 | 2017031535 | ND |
2017-10-30 | 2017031533 | ND |
2017-10-30 | 2017031534 | ND |
2018-06-04 | 1806144-002 | ND |
2018-07-09 | 2018018954 | ND |
2018-09-10 | 1809604-002 | ND |
2018-10-01 | 2018028329 | ND |