Diquat

  • Diquat dibromide
  • 1,1'-Ethylene-2,2'-bipyridyllium dibromide
Formula
C12H12Br2N2
Structure
Description
Colorless to yellow crystals.
Uses
Contact herbicide used also to produce desiccation & defoliation.

Registry Numbers and Inventories.
CAS
85-00-7
EC (EINECS/ELINCS)
201-579-4
EC Index Number
613-089-00-1
EC Class
Very toxic; Toxic; Harmful; Irritant; Sensitising; Dangerous for the Environment
RTECS
JM5690000
RTECS class
Agricultural Chemical and Pesticide; Mutagen; Reproductive Effector; Human Data; Primary Irritant
UN (DOT)
2781
Merck
12,3415
Beilstein/Gmelin
3769318
Beilstein Reference
4-23-00-01589
EPA OPP
32201
Swiss Giftliste 1
G-1594
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C12H12N2*2Br
Formula mass
344.05
Melting point, °C
335-340
Vapor pressure, mmHg
<0.00001 (25 C)
Density
1.22-1.27 g/cm3 (20 C)
Solubility in water
700 g/L
Partition coefficient, pKow
3.05

Hazards and Protection.
Storage
Keep containers tightly closed in a well ventilated area away from food products. Keep away from heat and water.
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
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Cover with plastic sheet to prevent spreading. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS.
Stability
No data.
Decomposition
When heated to decomposition, diquat dibromide emits very toxic fumes of nitrogen oxides and hydrogen bromide.

Fire.
Fire fighting
Use method most appropriate to fight surrounding fire.
Fire potential
Combustible solid.
Combustion products
When heated to decomposition, diquat dibromide emits very toxic fumes of nox and hbr.

Health.
Exposure limit(s)
NIOSH REL: TWA 0.5 mg/m3
Poison_Class
3
Exposure effects
Diquat has not produced any pathological evidence of neurotoxicity or neurological lesions in experimental animals, although at high doses, depression, lethargy, collapse, coma, and death were seen. 1. In human diquat poisonings, approximately 50% of patients have neurologic effects (e.G., Nervousness, agitated behavior, combativeness, diminished reflexes, lethargy, inability to recognize familiar persons, nonsensical statements, stupor, coma). A. The cause of these effects is not known. Onset has been observed as early as the first day following the poisoning. Seizures may occur with severe intoxication. Diquat has not been associated with teratogenicity or adverse reproductive effects.
   Inhalation
Overexposure to diquat spray mist may result in upper respiratory tract irritation with epistaxis, sore throat, coughing, chest tightness, and breathing difficulties. Systemic diquat toxicity does not involve the development of pulmonary fibrosis.
   Skin
Severe skin irritation or burns may result from prolonged direct contact. Diquat can be absorbed through damaged or injured skin, resulting in systemic poisoning. Absorption through intact skin is minimal.
   Eyes
Eye contact with diquat concentrate or strong solutions may result in severe irritation. No permanent eye damage has been reported in humans.

First aid
 
   Ingestion
Ipecac induced vomiting is not recommended because of the potential for cns depression, seizures and cardiovascular instability.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
   Skin
Remove and isolate contaminated clothing and shoes. Remove material from skin immediately. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
2781
Response guide
Hazard class
6.1
Packing Group
I; II; III
 
USCG CHRIS Code
DIQ