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1、第四章污染物的生态毒理(EcotoxicologyofPollutants)内容第一节毒理学与生态毒理学第二节吸收、分布、代谢、排泄第三节生物富集、放大与积累第四节污染物生物转化第五节毒物、毒性内容第一节毒理学与生态毒理学一、毒理学(Toxicology)二、生态毒理学(Ecotoxicology)一、毒理学ToxicologyToxicology(fromtheGreekwordstoxicosandlogos)isthestudyoftheadverseeffectsofchemicalsonlivingorganisms[1].Itisth
2、estudyofsymptoms,mechanisms,treatmentsanddetectionofpoisoning,especiallythepoisoningofpeople.Toxicologystudiestherelationshipbetweendoseanditseffectsonthelivingorganism.Thechiefcriterionregardingthetoxicityofachemicalisthedose,i.e.theamountofexposuretothesubstance.Almostallsubst
3、ancesaretoxicundertherightconditions.RelationshipBetweenDoseandToxicity一、毒理学ToxicityofMetabolitesManysubstancesregardedaspoisonsaretoxiconlyindirectly.Anexampleis"woodalcohol,"ormethanol,ischemicallyconvertedtoformaldehydeandformicacidintheliver.Itistheformaldehydeandformicacid
4、thatcausethetoxiceffectsofmethanolexposure.Manydrugmoleculesaremadetoxicintheliver,agoodexamplebeingacetaminophen(paracetamol),especiallyinthepresenceofalcohol.二、生态毒理学EcotoxicologyTheterm"ecotoxicology"wascoinedbyTruhautin1969,whodefineditas"thebranchoftoxicologyconcernedwithth
5、estudyoftoxiceffects,causedbynaturalorsyntheticpollutants,totheconstituentsofecosystems,animal(includinghuman),vegetableandmicrobial,inanintegralcontext”(Truhaut,1977).Ecotoxicologyisallegedtobetheintegrationoftoxicologyandecologyor,asChapman(2002)suggested“ecologyinthepresenceo
6、ftoxicants”.Itaimstopredicttheeffectsuponnaturalpopulations,communities,orecosystems-‘theecosystem’-ofstressors,betheyanthropogenicinoriginorotherwise.内容第二节吸收、分布、代谢、排泄一、物质通过生物膜的方式二、污染物质在生物体内的转运一、物质通过生物膜的方式ADMEADMEisanacronyminpharmacokineticsandpharmacologyforabsorption,distri
7、bution,metabolism,andexcretion,anddescribesthedispositionofapharmaceuticalcompoundwithinanorganism.1.生物膜的结构70年代(SingerandNicholson,1972)提出的液态镶嵌模型:磷脂双分子层构成细胞膜的骨架(75-100Å),亲水基团排列于内外两面;蛋白质分子覆盖、镶嵌、贯穿(物质转运的载体,酶;膜孔)。一、物质通过生物膜的方式生物膜脂质双分子层结构一、物质通过生物膜的方式(1)膜孔过滤2.物质通过生物膜的方式脂溶性物质从高浓度向低浓度
8、侧扩散。扩散速率服从费克定律。直径小于膜孔的水溶性物质,可借助膜两侧的静水压及渗透压经膜孔滤过