Insecticide

carbamate

NOMENCLATURE

Common name fenobucarb (BSI, draft E-ISO, (m) draft F-ISO); BPMC (JMAF, Thailand)

IUPAC name 2-sec-butylphenyl methylcarbamate 

Chemical Abstracts name 2-(1-methylpropyl)phenyl methylcarbamate 

CAS RN [3766-81-2]  EEC no. 223-188-8  Development codes Bayer 41 367c  Official codes OMS 313 

PHYSICAL CHEMISTRY

Composition Tech. is >97%.  Mol. wt. 207.3  M.f. C12H17NO2  Form Colourless solid; (tech., colourless to yellow-brown liquid or solid).  M.p. 31-32 ºC; (tech., 26.5-31 ºC)  B.p. 112-113 ºC/0.02 mmHg  V.p. 13 mPa (20 ºC)  KOW logP = 2.79  Henry 6.4 ´ 10-3 Pa m3 mol-1 (calc.)  S.g./density 1.035 at 30 ºC  Solubility In water 420 mg/l (20 ºC), 610 mg/l (30 ºC). In acetone, benzene, chloroform, xylene, toluene >1 (all in kg/kg, room temperature).  Stability Stable under normal storage conditions. Stable to light. Hydrolysed by acids and alkalis; (20 ºC) DT50 >28 d (buffer at pH 2), 16.9 d (pH 9), 2.06 d (pH 10).  F.p. 142 °C (closed system) 

COMMERCIALISATION

History Insecticide reported by R. L. Metcalf et al. (J. Econ. Entomol., 1962, 55, 889). Introduced by Sumitomo Chemical Co., Ltd, by Kumiai Chemical Industry Co., Ltd and Mitsubishi Chemical Industries (now Mitsubishi Chemical Corp.) jointly, and by Bayer AG (who no longer manufacture or market it); registered in Japan and first marketed in 1968.  Manufacturers Hunan Linxiang; Jin Hung; Mitsubishi Chemical; Kuo Ching; Shenzhen Jiangshan; Sinon; Sumitomo; Taiwan Tainan Giant

APPLICATIONS

Biochemistry Cholinesterase inhibitor.  Mode of action Non-systemic insecticide with contact action.  Uses Control of leafhoppers, planthoppers, thrips, and weevils on rice, tea, sugar cane, wheat, cucurbits, aubergines, and capsicums. Control of bollworms and aphids on cotton, at 0.5-1.0 kg/ha; control of leafhoppers, at 0.6-1.2 kg/ha.  Formulation types DP; EC; UL.  Selected tradenames: 'Bassa' (Mitsubishi Chemical, Kumiai); 'Osbac' (Sumitomo); 'Merlin' (Nagarjuna Agrichem)

OTHER TRADENAMES

'Baycarb' (Bayer); 'Vibasa' (Vipesco); 'Zhongdingwei' (Shenzhen Jiangshan) mixtures: 'Kasu-rab-sumibassa' (+ fenitrothion+ kasugamycin hydrochloride hydrate+ phthalide) (Hokko); 'Mitecidin' (+ polynactins) (Eikou Kasei); 'Vibaba' (+ diazinon) (Vipesco); 'Vibam' (+ dimethoate) (Vipesco); 'Viphensa' (+ phenthoate) (Vipesco)

ANALYSIS

Product analysis by u.v. spectrometry of a derivative or by hplc (CIPAC Handbook, 1988, D, 86). Details available from Sumitomo Chemical Co., Ltd. 

MAMMALIAN TOXICOLOGY

Oral Acute oral LD50 for male rats 623, female rats 657 mg/kg.  Skin and eye Acute percutaneous LD50 for rabbits 10 250 mg/kg.  Inhalation LC50 (4 h) for rats >0.366 mg tech./l air.  NOEL (2 y) for rats 4.1 mg/kg b.w. daily (100 mg/kg diet).  Toxicity class WHO (a.i.) II; EPA (formulation) II  EC hazard Xn; R22| N; R50, R53 

ECOTOXICOLOGY

Birds Acute oral LD50 for mallard ducks 323 mg/kg. Dietary LC50 (5 d) for mallard ducks >5500, bobwhite quail 5417 mg/kg diet.  Fish LC50 (48 h) for carp 16 mg/l.  Daphnia LC50 (3 h) 0.32 mg/l. 

ENVIRONMENTAL FATE