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EWG's Tap Water Database — 2019 UPDATE

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Diquat

Hca Roan Filter Plant

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

 

5

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012N/A00N/A
2013ND10ND
2014ND20ND
2015N/A00N/A
2016N/A00N/A
2017ND20ND

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
2013-04-2213042084-01ND
2014-04-1014041261-01ND
2014-07-1714072291-01ND
2017-04-1715953922ND
2017-07-2016582828ND