chlorpropham 2.5% SP 99% TC 2025 most popular

NOMENCLATURE

Common name chlorpropham (BSI, E-ISO, WSSA); chlorprophame ((m) F-ISO); IPC (JMAF); chlor-IFC (USSR)

IUPAC name isopropyl 3-chlorocarbanilate; isopropyl 3-chlorophenylcarbamate  

Chemical Abstracts name 1-methylethyl (3-chlorophenyl)carbamate  

Other names CIPC; chloro-IPC  CAS RN [101-21-3]  EEC no. 202-925-7  Official codes ENT 18 060  

PHYSICAL CHEMISTRY

Composition Tech. grade is 98.5% pure.  Mol. wt. 213.7  M.f. C10H12ClNO2  Form Colourless solid.  M.p. 41.4  (pure); 38.5-40  (tech.)  B.p. 256-258  (>98% pure)  V.p. 24 mPa (20 , 98% pure)  KOW logP = 3.79 (pH 4, 20 )  Henry 0.047 Pa m3 mol-1 (20 )  S.g./density 1.180 (30 )  Solubility In water 89 mg/l (25 ). Readily soluble in most organic solvents, e.g. alcohols, ketones, esters, chlorinated hydrocarbons, aromatic hydrocarbons, etc. Moderately soluble in mineral oils (e.g. 100 g/kg in kerosene).  Stability Stable to u.v. light. Decomposes above 150 . Hydrolysed slowly in acidic and alkaline media.  

COMMERCIALISATION

History Herbicide reported by E. D. Witman & W. F. Newton (Proc. Northeast. Weed Control Conf., 1951, p. 45). Introduced in 1951.  Patents US 2695225  Manufacturers Cerexagri; Hodogaya; Kemira FC; United Phosphorus Ltd

APPLICATIONS

Biochemistry Mitosis inhibitor (microtubule organisation).  Mode of action Selective systemic herbicide and growth regulator, absorbed predominantly by the roots and coleoptiles, and readily translocated acropetally.  Uses Pre-emergence control of many annual grasses and some broad-leaved weeds in onions, leeks, garlic, shallots, alfalfa, clover, sugar beet, spinach, lettuce, endive, chicory, herbs, peas, beans, carrots, celery, black salsify, fennel, soya beans, cotton, rice, safflowers, sunflowers, cranberries, cane berries, ornamentals (especially bulb flowers), ornamental trees and shrubs, perennial grass-seed crops, etc. Also used as a sprouting inhibitor for ware potatoes, and as a sucker control agent in tobacco. Often used in combination with propham as a potato sprouting inhibitor, and in combination with other herbicides. Formulation types DP; EC; GR; HN.  Selected products: 'Gro-Stop' (Luxan); 'Neostop' (Agriphar)

ANALYSIS

Product analysis by glc (Anal. Methods Pestic. Plant Growth Regul., 1972, 6, 612; CIPAC Handbook, 1985, 1C, 2025), or by titration of the carbon dioxide or 3-chloroaniline formed on hydrolysis (CIPAC Handbook, 1970, 1, 223; ibid., 1983, 1B, 1757; FAO Specification CP/73). Residues determined by glc or hplc of derivatives (Anal. Methods Pestic. Plant Growth Regul., loc. cit.). In drinking water, by glc with NPD (AOAC Methods, 17th Ed., 991.07).  

MAMMALIAN TOXICOLOGY

Reviews FAO/WHO 89, 91 (see part 2 of the Bibliography).  IARC ref. 12  class 3  Oral Acute oral LD50 for rats 5000-7500, rabbits 5000 mg/kg.  Skin and eye Acute percutaneous LD50 for rabbits >2000 mg/kg. Not a skin or eye irritant. Is a skin sensitiser (guinea pigs).  NOEL In 2 y feeding trials, rats and dogs receiving 2000 mg/kg diet showed no ill-effects.  ADI (JMPR) 0.03 mg/kg b.w. [2000].  Toxicity class WHO (a.i.) U; EPA (formulation) III  

ECOTOXICOLOGY

Birds Acute oral LD50 for mallard ducks >2000 mg/kg.  Fish LC50 (48 h) for bluegill sunfish 12, bass 10 mg/l.  Daphnia LC50 (48 h) 3.7 mg/l.  Algae EC50 (96 h) for Selenastrum capricornutum 3.3 mg/l.  Bees Not hazardous to bees when used as recommended.  Worms LC50 62 mg/kg.  

ENVIRONMENTAL FATE

Animals In mammals, following oral administration, the principal metabolic route is by hydroxylation at the para position and conjugation of the resultant 4-hydroxychloropropham with sulfate. There is also some hydroxylation of the isopropyl residue.  Plants In soya beans, three major metabolites have been identified, isopropyl N-4-hydroxy-3-chlorophenylcarbamate, isopropyl N-5-chloro-2-hydroxyphenylcarbamate, and 1-hydroxy-2-propyl-3'-chlorocarbanilate, whilst, in cucumbers, only the first of these has been identified. These aglycones are found in plants as water-soluble conjugates of glucose or other plant components.  Soil/Environment In soil, microbial degradation leads to the production of 3-chloroaniline by an enzymic hydrolysis reaction, with liberation of CO2. DT50 in soil c. 65 d (15 ), 30 d (29 ).