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EWG's Tap Water Database — 2019 UPDATE

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Diquat

Hilo

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

 

18

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND80ND
2013N/A00N/A
2014N/A00N/A
2015N/A00N/A
2016ND80ND
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
2012-04-30201205030005ND
2012-04-30201205030010I1ND
2012-04-30201205030010I2ND
2012-04-30201205030017ND
2012-10-15201210170604ND
2012-10-15201210170563ND
2012-10-15201210170562ND
2012-10-15201210170553ND
2016-02-22ND
2016-02-22ND
2016-02-22ND
2016-02-22ND
2016-06-01ND
2016-06-01ND
2016-06-01ND
2016-06-01ND
2017-05-09ND
2017-08-16ND