Know Your Environment. Protect Your Health.

Diquat

Quarryville Borough

NOTE: Quarryville Borough purchases water from Pennsylvania American Coatesville which is required to test for diquat. Sample information shown below was taken by Pennsylvania American Coatesville.

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

 

4

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
2019N/A00N/A
2020ND10ND
2021N/A00N/A
2022N/A00N/A
2023ND10ND

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: Quarryville Borough purchases water from Pennsylvania American Coatesville which is required to test for diquat. Sample information shown below was taken by Pennsylvania American Coatesville.

Date Lab ID Result
2020-04-0722015062.00ND
2020-07-0822600275.00ND
2023-04-0428694671.00ND
2023-07-0629295011.00ND