Paraquat (restricted-use herbicide)

Trade name(s) Gramoxone Extra, Gramoxone Max, Gramoxone Inteon, Cyclone, Cyclone Concentrate, Firestorm, Parazone

Manufacturer(s) Syngenta, Griffin, Chemtura, ADAMA, AMVAC

Formulation(s) The cation part of the molecule is the active ingredient. 2, 2.5, and 3 lb/gal of the water-soluble cation. The formulation is a distinct green and contains a stenching agent to help prevent accidental swallowing. An emetic is added to induce vomiting in case it is consumed.

Remarks A postemergence, nonselective, somewhat translocated herbicide with fast-acting contact action. Toxic if swallowed, inhaled, or absorbed through the skin. Use protective clothing to avoid inhaling or contact with the skin.

Water solubility Completely soluble.

Storage conditions Store above 32°F.

Acute toxicity LD50 - 157 mg/kg

Action in plant Acts as contact; absorbs energy produced during photosynthesis and forms peroxides that disrupt living cells.

Site of action Group 22: photosystem I electron diversion

Chemical family Bipyridilium

Koc Estimated at 1,000,000 mL/g