Diazinon 二嗪磷

二嗪磷

中文通用名称: 二嗪磷
英文通用名称: Diazinon
分子式：C12H21N2O3PS
化学名称: O，O-二乙基-O-（2-异丙基-6-甲基-4-嘧啶基）硫逐磷酸酯 .

理化性质 : ：黄色液体，沸点83-84℃/26.6Pa,蒸气压12MPa(25℃),相对密度 1.11,在水中溶解度(20℃)为60mg/L,与普通有机溶剂不混溶。100℃以上易氧化，中性介质稳定，碱性介质中缓慢水解，酸性介质中加速水解。

用途 ： 用于控制大范围作物上的刺吸式口器害虫和食叶害虫，包括落叶果树、柑桔、葡萄、橄榄、香蕉、菠萝、蔬菜、马铃薯、甜菜、甘蔗、咖啡、可可、茶树等。

毒性 : 本品中毒；大鼠急性经口LD50150-600mg/kg；大鼠急性经皮LD50为911mg/kg。

【使用方法】
1．蔬菜害虫 防治菜青虫，在产卵高峰后1星期，幼虫2～3龄期防治。每667平方米用50％乳油40——50毫升(有效成分20~25克)，对水40～50千克喷雾。防治蚜虫，用药量和使用方法同菜青虫。防治圆葱潜叶蝇、豆类种蝇，每667平方米用50％乳油50～100毫升(有效成分25——50克)，对水50～100千克喷雾。
2．棉花害虫 防治棉蚜，苗蚜有蚜株率达30％，单株平均蚜量近10头，卷叶率达5％时，每667平方米用50％乳油40～60毫升(有效成分20----30克)，对水40--60千克喷雾。防治红蜘蛛，6月底以前的害螨发生期，每667平方米用50％乳油60～80毫升(有效成分30----40克)，对水50千克喷雾。
3．水稻害虫 防治三化螟，防治枯心应掌握在卵孵盛期，防治白穗在5％～10％破口露穗期，每667平方米用50％乳油50——75毫升(有效成分25～37.5克），对水50～75千克喷雾，防治二化螟，大发生年份蚁螟孵化高峰前3天第一次用药，7～l0天再用药一次，用药量及方法同三化螟。防治稻瘿蚊，主要防治中、晚稻秧苗田，防止将虫源带入本田。在成虫高峰期至幼虫孵化高峰期用药，每667平方米用50％乳油50一100毫升(有效成分25——50克)，对水50——75千克喷雾。防治稻飞虱、叶蝉、稻杆蝇，在发生期用药，用药量和使用方法同稻瘿蚊。
4．地下害虫 防治华北蝼蛄、华北大黑金龟子，用50％乳油500毫升(有效成分250克)，加水25千克，拌玉米或高粱种300千克，拌匀闷种7小时后播种。同样药量和对水量，可拌小麦种250千克，待种子吸收药液，稍晾干后播种。防治春播花生田大黑蛴螬，每667平方米用2％颗粒剂1．25千克（有效成分25克），穴肥。

【注意事项】
1．不可与碱性农药混用。本品不可与敌稗混用，也不可在施用敌稗前后两周内使用本品。
2．作物收获前10天内，停止用药。
3．本品不能用铜、铜合金罐、塑料瓶盛装。贮存时放置在阴凉干燥处。
4．解毒剂有硫酸阿托品、解磷定等。

diazinon
Insecticide, acaricide
IRAC 1B; organophosphate

NOMENCLATURE
Common name diazinon (BSI, E-ISO, (m) F-ISO, ANSI, ESA, BAN, JMAF); dimpylate (INN)
IUPAC name O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate
Chemical Abstracts name O,O-diethyl O-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] phosphorothioate
CAS RN [333-41-5] EEC no. 206-373-8 Development codes G 24 480 (Geigy) Official codes OMS 469; ENT 19 507

PHYSICAL CHEMISTRY
Composition Tech. is ³95% pure. Mol. wt. 304.3 M.f. C12H21N2O3PS Form Clear colourless liquid; (tech., yellow liquid). B.p. 83-84 ºC/0.0002 mmHg; 125 ºC/1 mmHg V.p. 1.2 ´ 101 mPa (25 ºC) (OECD 104) KOW logP = 3.30 (OECD 107) Henry 6.09 ´ 10-2 Pa m3 mol-1 (calc.) S.g./density 1.11 (20 ºC) Solubility In water 60 mg/l (20 ºC). Completely miscible with common organic solvents, e.g. ethers, alcohols, benzene, toluene, hexane, cyclohexane, dichloromethane, acetone, petroleum oils. Stability Susceptible to oxidation above 100 ºC. Stable in neutral media, but slowly hydrolysed in alkaline media, and more rapidly in acidic media; DT50 (20 ºC) 11.77 h (pH 3.1), 185 d (pH 7.4), 6.0 d (pH 10.4). Decomposes above 120 ºC. pKa 2.6 (OECD 112) F.p. ³62 °C

COMMERCIALISATION
History Insecticide reported by R. Gasser (Z. Naturforsch. Teil B, 1953, 8, 225). Introduced in 1953 by J. R. Geigy S.A. (now Syngenta AG). Patents BE 510817; GB 713278 Manufacturers Aako; Agrochem; Cerexagri; Drexel; Hebei Golhil; Hegang Heyou; Hesenta; Makhteshim-Agan; Nippon Kayaku; Sannong; Sudarshan; Sundat; Syngenta

APPLICATIONS
Biochemistry Cholinesterase inhibitor. Mode of action Non-systemic insecticide and acaricide with contact, stomach, and respiratory action. Uses Control of sucking and chewing insects and mites on a very wide range of crops, including deciduous fruit trees, citrus fruit, vines, olives, bananas, pineapples, vegetables, potatoes, beet, sugar cane, coffee, cocoa, tea, tobacco, maize, sorghum, alfalfa, flax, cotton, rice, ornamentals, glasshouse crops, forestry, etc., at 300-600 g/ha; soil insects (by soil application); phorid and sciarid flies in mushroom cultivation; flies, lice, mites, fleas, cockroaches, bedbugs, ants, and other insect pests in animal houses and household use. Seed treatment for maize, for control of frit flies and also conferring bird-repellent properties. Also used as a veterinary ectoparasiticide. Phytotoxicity Non-phytotoxic when used as directed. Russetting may occur on green and yellow apple varieties. Formulation types CS; EC; DP; DS; FT; GR; KN; SD; WP; Aerosol; Coating agent. Compatibility Incompatible with copper-containing compounds. Selected products: 'Basudin' (Syngenta); 'Neocidol' (veterinary use) (Syngenta); 'Cekuzinon' (Cequisa); 'Devizinon' (Devidayal); 'Dianon' (Nippon Kayaku); 'Dianozyl' (Agriphar); 'Diazol' (Makhteshim-Agan, AgroSan); 'Efdiazon' (Efthymiadis); 'Knox-out' (Cerexagri); 'Vibasu' (Vipesco); 'Zak' (Kemio)

OTHER PRODUCTS
'DZN' (Syngenta); 'Nucidol' (veterinary use) (Syngenta); 'Agrozon' (Chemvet); 'D-264' (Drexel); 'Diasol' (Makhteshim-Agan); 'Geofos D' (Siapa); 'Granudin' (Agricultura Nacional); 'Kayazinon' (Nippon Kayaku); 'Metazon' (Agrochem); 'Vetazon' (veterinary use) (Chemvet) mixtures: 'Agrox D-L Plus' (+ gamma-HCH+ captan) (Agriliance); 'Agrox Premiere' (+ gamma-HCH+ metalaxyl+ captan) (Agriliance); 'Bipol' (+ permethrin) (Kemio); 'Kernel Guard' (+ gamma-HCH+ captan) (Trace); 'Kick Start' (+ gamma-HCH+ carboxin) (Helena); 'Ondia' (+ benfuracarb) (Otsuka); 'Super Homai' (+ thiophanate-methyl+ thiram) (Nippon Soda); 'Vibaba' (+ fenobucarb) (Vipesco) Discontinued products: 'Kayazol' * (Nippon Kayaku)

ANALYSIS
Product analysis by glc with FID (CIPAC Handbook, 1998, H, 122; Anal. Methods Pestic. Plant Growth Regul., 1972, 6, 345; AOAC Methods, 17th Ed., 971.08, 982.06). Residues determined by glc with TID, FPD or MCD, by tlc, by paper chromatography, or by single sweep oscillographic polarography (ibid., 968.24*, 970.33, 970.52, 970.53*; Analyst (London), 1980, 105, 515; Man. Pestic. Residue Anal., 1987, I, 5, 6, S8, S10, S13, S17, S19; Anal. Methods Residues Pestic., 1988, Part I, M2, M5, M12). In drinking water, by glc with NPD (AOAC Methods, 17th Ed., 991.07).

MAMMALIAN TOXICOLOGY
Reviews FAO/WHO 68, 70, 92, 94 (see part 2 of the Bibliography). Oral Acute oral LD50 for rats 1250, mice 80-135, guinea pigs 250-355 mg/kg. Skin and eye Acute percutaneous LD50 for rats >2150, rabbits 540-650 mg/kg. Not an irritant (rabbits). Inhalation LC50 (4 h) for rats >2330 mg/m3. NOEL (2 y) for rats 0.06 mg/kg b.w.; (1 y) for dogs 0.015 mg/kg b.w. daily, humans 0.02 mg/kg b.w. ADI (JMPR) 0.002 mg/kg b.w. [1993, 2001]. Toxicity class WHO (a.i.) II; EPA (formulation) II or III EC classification Xn; R22| N; R50, R53

ECOTOXICOLOGY
Birds Acute oral LD50 for mallard ducklings 2.7, young pheasants 4.3 mg/kg. Fish LC50 (96 h) for bluegill sunfish 16, rainbow trout 2.6-3.2, carp 7.6-23.4 mg/l. Daphnia LC50 (48 h) 0.96 mg/l. Algae >1 ppm. Bees Highly toxic to bees. Worms Slightly toxic to earthworms.

ENVIRONMENTAL FATE
EHC 198 (WHO 1998), 63 (WHO, 1986; a general review of organophosphorus insecticides). Animals The principal metabolites are diethyl thiophosphate and diethyl phosphate. Plants Studies with 14C-labelled diazinon show a rapid absorption and translocation in plants. Metabolism proceeds via hydrolysis and subsequent transformation and degradation of the hydroxypyrimidine derivatives to CO2. Soil/Environment Degradation involves oxidation to the phosphate (diazoxon) and hydrolysis (J. Pardue et al., J. Agric. Food Chem., 1970, 18, 405-408). DT50 c. 11-21 d (laboratory). Diazinon is fairly strongly adsorbed onto soil; Kom 332 mg/g o.m. Mobility is low.