Diquat

Darbonne Ws North

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

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2014	ND	2	ND
2015	N/A	0	N/A
2016	N/A	0	N/A
2017	ND	12	ND
2018	N/A	0	N/A
2019	ND	10	ND

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
2014-12-01	AE00107	ND
2014-12-01	AE00107	ND
2017-02-04	35293411005	ND
2017-02-04	35293411004	ND
2017-02-04	35293411003	ND
2017-02-04	35293411001	ND
2017-02-04	35293411002	ND
2017-02-04	35293411003	ND
2017-02-04	35293411004	ND
2017-02-04	35293411005	ND
2017-02-04	35293411002	ND
2017-02-04	35293411001	ND
2017-11-06	35346857001	ND
2017-11-06	35346857001	ND
2019-09-09	35496832001	ND
2019-09-09	35496832005	ND
2019-09-09	35496832004	ND
2019-09-09	35496832003	ND
2019-09-09	35496832002	ND
2019-09-09	35496832001	ND
2019-09-09	35496832005	ND
2019-09-09	35496832004	ND
2019-09-09	35496832003	ND
2019-09-09	35496832002	ND