Know Your Environment. Protect Your Health.

Diquat

Downsville Water System

NOTE: Downsville Water System purchases water from Culbertson Water System which is required to test for diquat. Sample information shown below was taken by Culbertson Water System.

Diquat is a herbicide used on potato crops and aquatic weeds.

 

16

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018N/A00N/A
2019ND20ND
2020N/A00N/A
2021N/A00N/A
2022ND70ND
2023ND20ND

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

NOTE: Downsville Water System purchases water from Culbertson Water System which is required to test for diquat. Sample information shown below was taken by Culbertson Water System.

Date Lab ID Result
2019-10-2835508736001ND
2019-10-2835508736002ND
2019-10-2835508736003ND
2019-10-2835508736001ND
2019-10-2835508736002ND
2019-10-2835508736003ND
2022-01-1135690299003ND
2022-05-0435715589001ND
2022-09-2735750438003ND
2022-12-1235766640001ND
2022-12-1235766640002ND
2022-12-1235766640003ND
2022-12-1235766640004ND
2023-02-0135777093005ND
2023-02-0135777093006ND
2023-02-0135777093007ND