Paraquat

Paraquat
Names
Preferred IUPAC name
1,1′-Dimethyl[4,4′-bipyridine]-1,1′-diium dichloride
Other names
Paraquat dichloride; Methyl viologen dichloride; MVCl2; Crisquat; Dexuron; Esgram; Gramuron; Ortho Paraquat CL; Para-col; Pillarxone; Tota-col; Toxer Total; PP148; Cyclone; Gramixel; Gramoxone; Pathclear; AH 501; Bai Cao Ku.
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.016.015
UNII
  • InChI=1S/C12H14N2.2ClH/c1-13-7-3-11(4-8-13)12-5-9-14(2)10-6-12;;/h3-10H,1-2H3;2*1H/q+2;;/p-2 Y
    Key: FIKAKWIAUPDISJ-UHFFFAOYSA-L Y
  • InChI=1/C12H14N2.2ClH/c1-13-7-3-11(4-8-13)12-5-9-14(2)10-6-12;;/h3-10H,1-2H3;2*1H/q+2;;/p-2/fC12H14N2.2Cl/h;2*1h/qm;2*-1
  • InChI=1/C12H14N2.2ClH/c1-13-7-3-11(4-8-13)12-5-9-14(2)10-6-12;;/h3-10H,1-2H3;2*1H/q+2;;/p-2
    Key: FIKAKWIAUPDISJ-NUQVWONBAF
  • C[n+]1ccc(cc1)c2cc[n+](cc2)C.[Cl-].[Cl-]
Properties
C12H14Cl2N2
Molar mass 257.16 g·mol−1
Appearance Yellow solid
Odor faint, ammonia-like
Density 1.25 g/cm3
Melting point 175 to 180 °C (347 to 356 °F; 448 to 453 K)
Boiling point > 300 °C (572 °F; 573 K)
High
Vapor pressure <0.0000001 mmHg (20 °C)
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Toxic, environmental hazard
GHS labelling:
H301, H311, H315, H319, H330, H335, H372, H410
P260, P273, P280, P284, P301+P310, P305+P351+P338
Lethal dose or concentration (LD, LC):
57 mg/kg (rat, oral)
120 mg/kg (mouse, oral)
25 mg/kg (dog, oral)
22 mg/kg (guinea pig, oral)
3 mg/m3 (mouse, 30 min respirable dust)
3 mg/m3 (guinea pig, 30 min respirable dust)
1 mg/m3 (rat, respirable dust, 6 h)
6400 mg/m3 (rat, nonrespirable dust, 4 h)
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 0.5 mg/m3 (resp) [skin]
REL (Recommended)
TWA 0.1 mg/m3 (resp) [skin]
IDLH (Immediate danger)
1 mg/m3
Safety data sheet (SDS) Aldrich MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Paraquat (trivial name; /ˈpærəkwɒt/), or N,N′-dimethyl-4,4′-bipyridinium dichloride (systematic name), also known as methyl viologen, is a toxic organic compound with the chemical formula [(C6H7N)2]Cl2. It is classified as a viologen, a family of redox-active heterocycles of similar structure. It is one of the most widely used herbicides worldwide. It is quick-acting and non-selective, killing green plant tissue on contact.

Paraquat is highly toxic to humans and other animals. The toxicity and lethality depends on the dose and how the herbicide is absorbed by the body. In humans, paraquat damages the mouth, stomach, and intestines if it is ingested orally. Once absorbed in the body, paraquat causes particular damage to the lungs, kidneys, and liver. Paraquat's lethality is attributed to its enhancing production of superoxide anions and human lung cells can accumulate paraquat. Paraquat exposure has been strongly linked to the development of Parkinson's disease.

Paraquat may be in the form of salt with chloride or other anions; quantities of the substance are sometimes expressed by cation mass alone (paraquat cation, paraquat ion). The name is derived from the para positions of the quaternary nitrogens.