Diquat
North Penn Water Authority
Diquat is a herbicide used on potato crops and aquatic weeds.
30
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 |
|---|---|---|---|---|
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | ND | 22 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | ND | 8 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
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 |
|---|---|---|
| 2020-04-01 | 22022932.00 | ND |
| 2020-04-01 | 22023051.00 | ND |
| 2020-04-01 | 22023021.00 | ND |
| 2020-04-01 | 22022961.00 | ND |
| 2020-04-01 | 22022991.00 | ND |
| 2020-04-01 | 22023129.00 | ND |
| 2020-04-13 | 22023343.00 | ND |
| 2020-04-13 | 22023313.00 | ND |
| 2020-04-13 | 22023283.00 | ND |
| 2020-04-13 | 22023253.00 | ND |
| 2020-05-04 | 22215385.00 | ND |
| 2020-07-06 | 22607327.00 | ND |
| 2020-07-06 | 22607357.00 | ND |
| 2020-07-06 | 22607387.00 | ND |
| 2020-07-06 | 22607297.00 | ND |
| 2020-07-06 | 22608056.00 | ND |
| 2020-08-10 | 22799607.00 | ND |
| 2020-08-10 | 22799577.00 | ND |
| 2020-08-10 | 22799487.00 | ND |
| 2020-08-12 | 22799547.00 | ND |
| 2020-08-12 | 22799517.00 | ND |
| 2020-08-31 | 22999386.00 | ND |
| 2023-04-12 | 28702835.00 | ND |
| 2023-04-12 | 28702833.00 | ND |
| 2023-04-12 | 28702836.00 | ND |
| 2023-04-12 | 28702834.00 | ND |
| 2023-07-19 | 29498003.00 | ND |
| 2023-07-19 | 29498005.00 | ND |
| 2023-07-19 | 29498004.00 | ND |
| 2023-07-19 | 29498002.00 | ND |