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
Description
Colorless solid. Odorless.
Uses
Herbicide.

Registry Numbers and Inventories.
CAS
4685-14-7
EC (EINECS/ELINCS)
225-141-7
EC Index Number
613-006-00-9
RTECS
DW1960000
RTECS class
Agricultural Chemical and Pesticide; Mutagen; Human Data
Merck
12,7165
Beilstein/Gmelin
3590305
EPA OPP
61603
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

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 fighting
Respirator selection for
Fire potential
Non-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.
   Ingestion
Nausea, vomiting, diarrhea, and abdominal pain are common.
   Inhalation
Progressive 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.
   Skin
Dermatitis 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
 
   Ingestion
The 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.
   Inhalation
There 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.
   Eyes
Irrigate 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 Code
PQT