Where It Comes From
Farm uses (preharvest desiccant on crops) and aquatic weed control in canals, ponds, and reservoirs; some rights‑of‑way uses [2][5].
How You Are Exposed
Drinking water near treated water bodies or fields; residues on food; spray drift; skin and eye contact for workers during mixing or spraying [1][2][4].
Why It Matters
Swallowing can cause vomiting, dehydration, kidney failure, and can be fatal; eye exposure can cause severe irritation and lasting vision problems; repeated eye exposure has been linked to cataracts [1][4][5].
Who Is at Risk
Pesticide mixers/applicators and farmworkers; residents near treated fields or water; children and pets; people with kidney disease [1][2][4].
How to Lower Your Exposure
Follow posted re‑entry intervals; avoid treated water until reopened; wash produce; store herbicides securely; workers should use PPE and closed transfer systems; if your well is near treated water, consider testing and certified activated‑carbon or reverse‑osmosis filtration; public water systems must meet EPA’s 0.02 mg/L diquat limit [2][3].
References
- [1]ATSDR. ToxFAQs for Diquat. Agency for Toxic Substances and Disease Registry. https://www.atsdr.cdc.gov/toxfaqs/
- [2]U.S. EPA. National Primary Drinking Water Regulations – Diquat (MCL = 0.02 mg/L). https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations
- [3]WHO. Diquat in Drinking-water: Background document for development of WHO Guidelines for Drinking-water Quality. World Health Organization. https://www.who.int/
- [4]NIOSH. Pocket Guide to Chemical Hazards: Diquat dibromide. Centers for Disease Control and Prevention. https://www.cdc.gov/niosh/npg/
- [5]U.S. EPA. Reregistration Eligibility Decision (RED) for Diquat Dibromide. https://www.epa.gov/pesticide-reevaluation/