Paraquat

  • 4,4'-Bipyridinium, 1,1'-dimethyl
  • Dextrone
  • N,N'-Dimethyl-4,4'-Bipyridinium
  • N,N'-Dimethyl-gamma,gamma'-dipyridylium
  • Esgram
  • Weedol
Formula[C12H14N2]++
Structure
DescriptionColorless solid. Odorless.
UsesHerbicide.

Registry Numbers and Inventories.
CAS4685-14-7
EC (EINECS/ELINCS)225-141-7
EC Index Number613-006-00-9
RTECSDW1960000
RTECS class Agricultural Chemical and Pesticide; Mutagen; Human Data
Merck12,7165
Beilstein/Gmelin3590305
EPA OPP 61603
Austrailia AICSListed
New ZealandListed
Japan ENCS (MITI) Listed
Korea ECLListed

Properties.
Formula C12H14N2
Formula mass 186.12
Boiling point, °C 169-170 (1.0 torr)
Decomposition point, °C >300
Density 1.24 g/cm3 (20 C) (diC)hloride)
Solubility in water soluble
Partition coefficient, pKow -4.22 at pH 7.4

Hazards and Protection.
Storage Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection Employees should be provided with and required to use impervious clothing, gloves, face shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent skin contact with paraquat or solutions containing paraquat. Employees should be provided with and required to use dust-and splash-proof safety goggles where paraquat or solutions containing paraquat may contact the eyes.
Respirators Use NIOSH/MSHA approved respirator appropriate for exposure of concern.
Small spills/leaks Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Stability No data.
Incompatibilities Paraquat is incompatible with alkylarylsulfonate wetting agents. Avoid contact with strong oxidizers.

Fire.
Fire fightingRespirator selection for
Fire potentialNon-flammable in aqueous formulations.

Health.
Exposure limit(s)IDHL: 1.5 mg/m3
Exposure effects Abnormally low blood pressure may develop after large ingestion. Lethargy, headache and malaise may occur initially. Cerebral edema may occur. Adverse reproductive effects have been observed in humans and experimental animals after ingestion of paraquat.
   IngestionNausea, vomiting, diarrhea, and abdominal pain are common.
   InhalationProgressive pulmonary fibrosis associated with dyspnea and pulmonary edema may occur 3 to 14 days following exposure to paraquat. Pulmonary hemorrhage may occur with acute exposure.
   SkinDermatitis associated with dry and cracking skin may occur following dermal exposure. Nail atrophy may be noted. Paraquat is well absorbed through abraded or injured skin and dermal exposure may result in severe systemic toxicity and death.
   Eyes Protracted opacification of the cornea may result following eye exposure. Paraquat is a mucosal irritant; epistaxis and sore throat may develop after inhalation.

First aid
 
   IngestionThe possible benefit of early removal of some ingested material by cautious gastric lavage must be weighed against potential complications of bleeding or perforation. Activated charcoal activated charcoal binds most toxic agents and can decrease their systemic absorption if administered soon after ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   InhalationThere have been no substantiated cases of paraquat poisoning due to inhalation of fumes. Inhalation of spray mist does occur, but the droplets are usually large and deposit in the upper respiratory tract where they cause local irritant effects.
   Skin Remove contaminated clothing. Wash exposed area with soap and water. If symptoms persist, seek medical attention. Launder clothing before reuse.
   EyesIrrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
USCG CHRIS CodePQT