Diquat
Portland Water Bureau
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 | 3 | 0 | ND |
2015 | ND | 1 | 0 | ND |
2016 | N/A | 0 | 0 | N/A |
2017 | ND | 3 | 0 | ND |
2018 | ND | 1 | 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 |
---|---|---|
2014-04-08 | BB38036-S | ND |
2014-07-08 | BB42035-S | ND |
2014-08-26 | K1409156001-S | ND |
2015-06-17 | K1506612001-S | ND |
2017-04-04 | BB87017-S | ND |
2017-08-08 | BB92723-S | ND |
2017-09-07 | BB93991-S | ND |
2018-03-15 | BC03118-S | ND |