paraquat dichloride 276g/l 200g/l SL 27.6% 20% SL AS fast killing TOP 1 manufacturer

Descripción del producto

NOMENCLATURE

paraquat dichloride

IUPAC name 1,1'-dimethyl*4,4'-bipyridinediium dichloride; 1,1'-dimethyl*4,4'-bipyridinium dichloride; 1,1'-dimethyl*4,4'-bipyridylium dichloride  

Chemical Abstracts name 1,1'-dimethyl*4,4'-bipyridinium dichloride  

Other names methyl viologen  CAS RN [********5];[********2] bis(methyl sulfate)  EEC no. ********7  Development codes PP**8; PP**0 for bis(methyl sulfate) (both ICI)  

 

paraquat

Common name paraquat (BSI, E-ISO, (m) F-ISO, ANSI, WSSA, JMAF); no name (Germany)

IUPAC name 1,1'-dimethyl*4,4'-bipyridinediium; 1,1'-dimethyl*4,4'-bipyridinium; 1,1'-dimethyl*4,4'-bipyridylium  

Chemical Abstracts name 1,1'-dimethyl*4,4'-bipyridinium  

CAS RN [********7]  EEC no. ********7  

 

PHYSICAL CHEMISTRY

paraquat dichloride

Composition Not normally isolated from the tech. products, which are >*5% pure.  Mol. wt. **7.2  M.f. C*2H*4Cl2N2  Form Colourless, hygroscopic crystals.  M.p. Practically insoluble in most organic solvents.  Stability Stable in neutral and acidic media, but readily hydrolysed in alkaline media. Photochemically decomposed by u.v. irradiation in aqueous solution.  Manufacturer Agrowonderful

 

paraquat

Mol. wt. **6.3  M.f. C*2H*4N2  

 

COMMERCIALISATION

History Herbicidal properties of the dichloride and bis(methyl sulfate) described by R. C. Brian (Nature (London), ***8, **1, **6) and their properties reviewed by A. Calderbank (Adv. Pest Control Res., ***8, 8, **7). Both salts (though only the former is still sold) were introduced by ICI Plant Protection Division (now Syngenta AG). Herbicidal properties of paraquat dichloride discovered in ***5, and first marketed in ***2.

 

APPLICATIONS

paraquat dichloride

Biochemistry During photosynthesis, superoxide is generated, which damages cell membranes and cytoplasm.  Mode of action Non-selective contact herbicide, absorbed by the foliage, with some translocation in the xylem.  Uses Broad-spectrum control of broad-leaved weeds and grasses in fruit orchards (including citrus), plantation crops (bananas, coffee, cocoa palms, coconut palms, oil palms, rubber, etc.), vines, olives, tea, alfalfa, onions, leeks, sugar beet, asparagus, ornamental trees and shrubs, in forestry, etc. Also used for general weed control on non-crop land; as a defoliant for cotton and hops; for destruction of potato haulms; as a desiccant for pineapples, sugar cane, soya beans, and sunflowers; for strawberry runner control; in pasture renovation; and for control of aquatic weeds. For control of annual weeds, applied at 0.**1.0 kg/ha. Formulation types SL.  Compatibility Incompatible with alkaline materials, anionic surfactants, and clay-containing inert materials.  Selected products: 'Gramoxone' (Syngenta); 'Efoxon' (Efthymiadis); 'Herbaxon' (Westrade); 'Herbikill' (Vapco); 'Pilarxone' (Pilarquim); 'Total' (Barclay); 'Weedless' (Sanonda); mixtures: 'Seccatuttu' (+ diquat dibromide) (Syngenta)

 

OTHER PRODUCTS

paraquat dichloride

'Cyclone' (Syngenta); 'Starfire' (Syngenta); 'Weedol' (Syngenta); 'Boa' (Griffin); 'Crisquat' (Crystal); 'Dextrone' (Nomix-Chipman); 'Dipaxone' (Papaeconomou); 'Dragocson' (Agricultura Nacional); 'Herboxone' (Crystal); 'Priquat' (Efthymiadis); 'Scythe' (BASF) mixtures: 'Gramocil' (+ diuron) (Syngenta); 'PDQ' (+ diquat dibromide) (Syngenta); 'Preeglox L' (+ diquat dibromide) (Syngenta); 'Surefire' (+ diuron) (Syngenta); 'Antox' (+ MSMA) (Ancom); 'Anuron' (+ diuron) (Ancom); 'Crisquat D' (+ diuron) (Crystal); 'Dexuron' (+ diuron) (Nomix-Chipman); 'Herboxone D' (+ diuron) (Crystal); 'Myzet' (+ diquat dibromide) (Otsuka); 'Pardy' (+ diuron) (Agricultura Nacional); 'Priglox' (+ diquat dibromide) (Nihon Nohyaku); 'Speedway 2' (+ diquat dibromide) (Scotts UK); 'Spray Seed' (+ diquat dibromide) (Crop Care) Discontinued products: 'Speedway' * (Zeneca); 'Cekuquat' * (Cequisa); 'Osaquat' * (Productos OSA); 'Plusquat' * (Productos OSA) mixtures: 'Gramonol' * (+ monolinuron) (Zeneca); 'Parable' * (+ diquat dibromide) (Zeneca); 'Preglox' * (+ diquat dibromide) (Zeneca); 'Azote' * (+ amitrole) (Productos OSA); 'Duplex' * (+ amitrole) (Productos OSA)

 

ANALYSIS

Product analysis by colorimetry (AOAC Methods, *7th Ed., **9.*9; CIPAC Handbook, ***2, E, ******8; ***5, G, **8); free 4,4'-bipyridyl, ibid., ***8, H, **6; in mixture with diquat, by colorimetry (CIPAC Handbook, ***2, E, ****8; ibid., ***5, G, *9). Residues determined by colorimetry after reduction (Pestic. Anal. Man., ***9, II; A. Calderbank & S. H. Yuen, Analyst (London), ***5, *0, *9; P. F. Lott et al., J. Chromatogr. Sci., ***8, *6, **0; J. B. Leary, Anal. Methods Pestic. Plant Growth Regul., ***8, *0, **1). Residues in potatoes by rplc with dual channel u.v. detection (AOAC Methods, *7th Ed., **2.*7). Details of methods available from Syngenta.  

 

MAMMALIAN TOXICOLOGY

paraquat dichloride

Reviews FAO/WHO *7, *9 (see part 2 of the Bibliography).  Oral Acute oral LD*0 for rats ******9, guinea pigs ****8 mg/kg.  Skin and eye Acute percutaneous LD*0 for rats **1 mg paraquat ion/kg. Irritating to skin and eyes (rabbits). Absorption through intact human skin is minimal; exposures can cause irritation and a delay in the healing of cuts and wounds; can cause temporary damage to nails. Not a skin sensitiser (guinea pigs).  Inhalation No vapour toxicity. Extreme exposure to spray droplets may cause nose bleeding.  NOEL (1 y) for dogs 0.*5 mg/kg b.w. daily; (2 y) for rats 1.7 mg/kg b.w. daily.  ADI (JMPR) 0.**4 mg/kg b.w. (as paraquat ion) [***6].  Toxicity class WHO (a.i.) II; EPA (formulation) II (oral, a.i.); III (dermal, a.i.)  EC classification T+; R*6| T; R*4/*5, R*8/*5| Xi; R*6/*7/*8| N; R*0, R*3  

 

ECOTOXICOLOGY

paraquat dichloride

Birds Acute oral LD*0 for bobwhite quail **5, mallard ducks **9 mg/kg. LC*0 (5 d) for bobwhite quail **1, Japanese quail **0, mallard ducks ***8, ring-necked pheasant ***8 mg/kg.  Fish LC*0 (*6 h) for rainbow trout *6, mirror carp **5 mg/l.  Daphnia EC*0 (*8 h) 6.1 mg/l.  Algae EbC*0 (*6 h) 0.*0 mg/l; ErC*0 0.*8 mg/l.  Bees LD*0 (*2 h) (oral) *6 mg/bee; (contact) **0 mg/bee.  Worms LC*0 >***0 mg/kg soil.  

 

ENVIRONMENTAL FATE

EHC *9 (WHO, ***4).  Animals In rats, following oral administration, ****0% of the dose was excreted in the faeces, and ****0% in the urine. Paraquat does not bioaccumulate, with >*0% of the dose eliminated in *2 h.  Plants On plant surfaces, photochemical degradation occurs. Degradation products which have been isolated include *-methyl**-carboxypyridinium chloride and methylamine hydrochloride.  Soil/Environment Paraquat is rapidly degraded by soil micro-organisms (DT*0 of unadsorbed paraquat *0 **0.