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农药基础知识与农药残留分析潘灿平农业部农产品质量监督检验测试中心（北京）Email：panc@cau.edu.cn农药残留分析基本流程取样、实验室样品、分析部位、提取、样品净化、仪器分析、分析报告、结果报告Stepsindeterminationofpesticideresidues•samplepreparation(laboratorysamplereceptionandverification,samplepreparationandprocessing,storageofsamples,preparationandhandlingofreferencestandards,storageofanalyticalstandards,andproceduresforcheckingstockstability)•extractionandclean-up,•quantitativedeterminationoftheanalyte(integrationandcalibration),•estimationofuncertaintyofresults,•confirmationoftheanalyte'sidentity,and•qualitycontrolproceduresforpesticideresidueanalysis.1、农药基础知识1）农药的定义与有关概念•Pesticide杀虫剂广义的农药的概念：农用化学品(Agrochemicals)•农药原药与制剂•农药的分类•不同化学结构的农药农药定义•农药定义：引自《农药管理条例》•农药主要是指用于预防、消灭或控制危害农业、林业的病、虫、草和其它有害生物以及有目的地调节植物、昆虫生长的化学合成或者来源于生物、其它天然物质的一种物质或者几种物质的混合物及其制剂。•Pesticidesarechemicalsthatweusetokillundesireableorganisms.•Whenwesayundesireableorganisms,wearereferringtoorganisms(plants,animals,insects,etc.)thatareharmfultous.Someoftheseorganisms,orpests,eatourcrops,whileothersspreaddiseases.Anditdoesn'talwayshavetobethisserious.Weedscanbeconsideredapestforjustgrowinginthewrongplaces(ouryards).Thepointis,ifweareusingsometypeofchemicaltocontrolthesepests,thatchemicalwouldbeconsideredapesticide.现代农业中农药的使用不可缺少•Theworldpopulationis5billionandgrowing.Ofthose,700millionareundernourished.Evenwiththeuseofpesticides,overone-thirdofourfoodislosttopests.•(Withoutpesticides,thelosseswillprobablybeevenhigher).Doyouthinkwecanaffordtofeedtheworldorganically?杀菌剂历史•杀菌剂是人类历史上最古老的药剂（公元前1000多年），从硫黄、石硫合剂、波尔多液、汞制剂，至今天的多种结构的化合物。有二硫代氨基甲酸酯类、苯并咪唑类、三唑类、吗啉类、酰胺类、嘧啶胺类等。•据英国植保协会出版的《ThePesticideManual》)介绍杀菌剂品种共200多种，新研发品种共230种左右。除草剂发展历史•20世纪40年代，H.B.Tukey和CeliaKirby等成功地合成和生产苯氧乙酸类除草剂，从此，对杂草的防治由人工进入化学防治阶段。•50年代，随着氨基甲酸酯类杀虫剂的出现，硫代氨基甲酸酯类除草剂也跟着进入农药市场，如扑草灭、苏达天、野麦畏、毒草胺、西玛津、赛克津等，现在有不少产品仍占有一定的市场。•以后又发明了有氟乐灵、敌草快，和二苯醚类除草剂。•70年代出现磺酰脲类除草剂甲磺隆、嘧磺隆、醚苯磺隆及氟嘧磺隆。磺酰尿类除草剂活性高，用量少，每公顷只需要15～150克即可，目前仍为销售量最高的除草剂。•Glyphosate，与转基因作物杀虫剂的历史•20世纪40年代问世的第一代杀虫剂是有机氯、有机磷杀虫剂，其代表化合物为DDT、666、艾氏剂、七氯等有机氯，对硫磷、特丁磷等有机磷。•第二代杀虫剂为氨基甲酸酯类农药，如西维因等。•第三代杀虫剂为除虫菊酯，它源于植物除虫菊，但光稳定性差。20世纪70年代，化学家们对其结构进行改造，生产出一批在当时为高效低毒的拟除虫菊酯，如：氰氯菊酯、溴氯菊酯、氰戊菊酯等。农药的历史•1948年，HermannMuller因为发明了化学农药DDT而获诺贝尔生理和医学奖Inthepast,malariawasonceaseriousdiseasethatkilledmillionsofpeopleglobally.(Thephotototherightshowstheredbloodcellsofsomeonewithmalaria.)Tofightthisproblem,weusedthepesticideDDT,tokillthemosquitoeswhichtransmittedthedisease.Itwassuccessful,andthenumberofpeoplewhodiedfrommalariashrankdrastically.firstmadeinalaboratoryin1873，founditsbiologicalactivityin1939•AtthebeginningofWorldWarII(1940),ourinsecticideselectionwaslimitedtoseveralarsenicals,petroleumoils,nicotine,pyrethrum,rotenone,sulfur,hydrogencyanidegas,andcryolite.ItwasWorldWarIIthatopenedtheModernEraofChemicalcontrolwiththeintroductionofanewconceptofinsectcontrol--syntheticorganicinsecticides,thefirstofwhichwasDDT.有机磷农药发展•ThesimilarityofOPchemicalstructurestothenervegases,theirmodesofactionarealsosimilar.TheirinsecticidalqualitieswerefirstobservedinGermanyduringWorldWarIIinthestudyoftheextremelytoxicOPnervegasessarin,soman,andtabun.•Initially,thediscoverywasmadeinsearchofsubstitutesfornicotine,whichwasheavilyusedasaninsecticidebutinshortsupplyinGermany.农药的其他基本概念•有效成分a.i.,activeingredient•剂型formulation•农药的通用名、商品名、化学名称•Chemicalname*•Commonname*•Productname*PesticideNames:•ChemicalName：•ThesystematicNameofaChemicalCompoundaccordingtotherulesofnomenclatureoftheInternationalUnionofPureandAppliedChemistryasadaptedforindexinginChemicalAbstracts.•Forexample:3,5,6-trichloro-2-pyridinyloxyaceticacid..isachemicalname.PesticideNames:CommonName•Agenericnameforachemicalcompound(seetheWeedScienceSocietyofAmericalistofherbicidenomenclature).Forexample:Thecommonnamefor3,5,6-trichloro-2-pyridinoxyaceticacid..istriclopyr.Thecommonnameisthenamegenerallyusedindiscussingpesticidaltoxicologyandenvironmentalbehaviorandfate.中英文通用名例子•chlorphoxim氯辛硫磷•chlorpropham氯苯胺灵•chlorpyrifos毒死蜱•chlorpyrifos-methyl甲基毒死蜱•chlorquinox四氯喹噁啉•chlorsulfuron(草案)氯磺隆•chlorthal-dimethyl氯酞酸甲酯•chlorthiamid氯硫酰草胺•chlorthiophos虫螨磷•chlortoluron绿麦隆•“西维因”，甲萘威，carbaryl,“Sevin”PesticideNames:ProductName•Thetradenameofapesticide;thatisthenameonthecontaineryoupurchase.ItisalsothenametowhichtheEPAregistrationnumberisappliedatthetimeofregistration.Triclopyraloneissoldas:Garlon3AorGarlon4.•一个农药制剂的商品名可以有多个。Activeingredient(s)有效成分•Thecomponent(s)ofaformulationresponsibleforthedirectorindirectbiologicalactivityagainstpestsanddiseases,orinregulatingmetabolism/growth,etc.•Asingleactiveingredientmaybecomprisedofoneormorechemicalorbiologicalentitieswhichmaydifferinrelativeactivity.•Aformulationmaycontainoneormoreactiveingredients.Formulation制剂•Apesticidepreparationcontainingtechnicalgradeactiveingredient(s)andformulant(s)inaformsuitableforuse.•Thepesticideproductofferedforsale.剂型：TypeofFormulation•农药原药的田间实际用量很少，一般是几克到百余克，为了把这少量的农药均匀地喷撒到农作物上，必须把农药原药加工成某种易于在田间均匀分布的粉剂、粒剂、供加水稀释的喷雾用的可湿性粉剂、浓悬乳剂、乳油等，农药原药必须加工成适宜的剂型才能使用。•l农药剂型是指具有一定组分和规格的农药加工形态•l一种剂型可以制成多种不同用途、不同含量的产品，即农药制剂•乳油：由原药（一般不溶于水）、有机溶剂（苯、二甲苯、樟脑油等）和乳化剂等经溶解混合而成单相透明油状液体制剂•粉剂：l供喷粉用的具有