Diquat

Honolulu-Windward-Pearl Harbor

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

218

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2013	N/A	0	N/A
2014	ND	98	ND
2015	N/A	0	N/A
2016	ND	4	ND
2017	ND	99	ND
2018	ND	11	ND
2019	ND	6	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
2014-02-19	201402210438	ND
2014-04-01	201404030466	ND
2014-04-01	201404030467	ND
2014-04-01	201404030468	ND
2014-04-01	201404030469	ND
2014-04-02	201404040550	ND
2014-04-02	201404040551	ND
2014-04-02	201404040552	ND
2014-04-02	201404040553	ND
2014-04-02	201404040554	ND
2014-04-04	201404080620	ND
2014-04-04	201404080621	ND
2014-04-07	201404090482	ND
2014-04-07	201404090483	ND
2014-04-07	201404090484	ND
2014-04-07	201404090485	ND
2014-04-08	201404100546	ND
2014-04-08	201404100547	ND
2014-04-08	201404100549	ND
2014-04-08	201404100550	ND
2014-04-08	201404100551	ND
2014-04-09	201404120256	ND
2014-04-09	201404120257	ND
2014-04-09	201404120258	ND
2014-04-11	201404150363	ND
2014-04-14	201404160551	ND
2014-04-14	201404160552	ND
2014-04-14	201404160553	ND
2014-04-14	201404160554	ND
2014-04-14	201404160555	ND
2014-04-14	201404160556	ND
2014-04-15	201404170340	ND
2014-04-15	201404170341	ND
2014-04-15	201404170342	ND
2014-04-15	201404170344	ND
2014-04-16	201404180401	ND
2014-04-16	201404180402	ND
2014-04-16	201404180403	ND
2014-04-16	201404180404	ND
2014-04-16	201404180405	ND
2014-04-16	201404180406	ND
2014-04-21	201404230599	ND
2014-04-22	201404240273	ND
2014-04-22	201404240274	ND
2014-04-23	201404250201	ND
2014-04-23	201404250202	ND
2014-04-28	201404300621	ND
2014-05-06	201405080376	ND
2014-07-07	201407091151	ND
2014-07-09	201407110319	ND
2014-07-09	201407110320	ND
2014-07-09	201407110321	ND
2014-07-14	201407170344	ND
2014-07-14	201407170345	ND
2014-07-14	201407170634	ND
2014-07-14	201407170635	ND
2014-07-15	201407170633	ND
2014-07-16	201407180291	ND
2014-07-16	201407180292	ND
2014-07-16	201407180293	ND
2014-07-16	201407180294	ND
2014-07-21	201407230644	ND
2014-07-22	201407240385	ND
2014-07-22	201407240386	ND
2014-07-22	201407240387	ND
2014-07-23	201407250454	ND
2014-07-23	201407250455	ND
2014-07-28	201407300353	ND
2014-07-28	201407300354	ND
2014-07-28	201407300355	ND
2014-07-28	201407300356	ND
2014-07-28	201407300357	ND
2014-07-28	201407300358	ND
2014-07-29	201407310301	ND
2014-07-29	201407310302	ND
2014-07-29	201407310303	ND
2014-07-29	201407310304	ND
2014-07-29	201407310305	ND
2014-07-30	201408010298	ND
2014-07-30	201408010299	ND
2014-07-30	201408010300	ND
2014-07-30	201408010301	ND
2014-08-06	201408080380	ND
2014-08-11	201408130617	ND
2014-08-11	201408130618	ND
2014-08-11	201408130619	ND
2014-08-11	201408130620	ND
2014-08-12	201408150106	ND
2014-08-12	201408150107	ND
2014-08-13	201408150180	ND
2014-08-13	201408150181	ND
2014-08-18	201408210214	ND
2014-08-18	201408210215	ND
2014-08-19	201408220168	ND
2014-08-26	201408290555	ND
2014-08-27	201408300150	ND
2014-10-28	201410300232	ND
2014-10-31	201411040539	ND
2016-02-09		ND
2016-04-13		ND
2016-05-02		ND
2016-10-28		ND
2017-02-14		ND
2017-04-03		ND
2017-04-03		ND
2017-04-05		ND
2017-04-05		ND
2017-04-11		ND
2017-04-11		ND
2017-04-11		ND
2017-04-11		ND
2017-04-17		ND
2017-04-17		ND
2017-04-18		ND
2017-04-18		ND
2017-04-19		ND
2017-04-19		ND
2017-04-19		ND
2017-04-19		ND
2017-04-19		ND
2017-04-19		ND
2017-04-20		ND
2017-04-26		ND
2017-05-01		ND
2017-05-01		ND
2017-05-02		ND
2017-05-03		ND
2017-05-03		ND
2017-05-03		ND
2017-05-03		ND
2017-05-03		ND
2017-05-04		ND
2017-05-09		ND
2017-05-09		ND
2017-05-09		ND
2017-05-10		ND
2017-05-10		ND
2017-05-11		ND
2017-05-16		ND
2017-05-16		ND
2017-05-17		ND
2017-05-22		ND
2017-05-22		ND
2017-05-22		ND
2017-05-22		ND
2017-05-22		ND
2017-05-23		ND
2017-05-23		ND
2017-05-24		ND
2017-05-30		ND
2017-06-05		ND
2017-06-06		ND
2017-06-07		ND
2017-06-13		ND
2017-07-05		ND
2017-07-05		ND
2017-07-07		ND
2017-07-07		ND
2017-07-10		ND
2017-07-11		ND
2017-07-11		ND
2017-07-12		ND
2017-07-12		ND
2017-07-14		ND
2017-07-14		ND
2017-07-14		ND
2017-07-14		ND
2017-07-17		ND
2017-07-17		ND
2017-07-17		ND
2017-07-17		ND
2017-07-19		ND
2017-07-19		ND
2017-07-19		ND
2017-07-19		ND
2017-07-19		ND
2017-07-19		ND
2017-07-25		ND
2017-07-25		ND
2017-07-25		ND
2017-07-25		ND
2017-07-26		ND
2017-07-26		ND
2017-07-31		ND
2017-07-31		ND
2017-08-01		ND
2017-08-01		ND
2017-08-02		ND
2017-08-02		ND
2017-08-04		ND
2017-08-04		ND
2017-08-07		ND
2017-08-07		ND
2017-08-07		ND
2017-08-07		ND
2017-08-07		ND
2017-08-07		ND
2017-08-11		ND
2017-08-15		ND
2017-08-15		ND
2017-10-26		ND
2018-02-12	201801080281	ND
2018-02-20	201801290307	ND
2018-03-28	201803300306	ND
2018-04-10	201804130358	ND
2018-04-23	201804270354	ND
2018-05-30	201805230584	ND
2018-06-12	201805230583	ND
2018-07-13	201807170605	ND
2018-07-25	201807270183	ND
2018-08-01	201808030195	ND
2018-08-08	201808110152	ND
2019-04-22	201904240396	ND
2019-07-09	201906200200	ND
2019-09-18	201909200252	ND
2019-09-25	201909270220	ND
2019-10-29	201910310278	ND
2019-12-24	201912180100	ND