项目解读甲醛

《生活饮用水卫生标准》GB5749-2006项目解读甲醛1概述1.1基本性质美国化学文摘(CA)编号500-00-0IUPAC对甲醛的命名为“methanal”分子式化0理化性质自然状态无色气体沸点。C-19.2熔点。C-118相对密度1.04(空气为1)蒸气压52.6kPa(-33C)水溶性(g/i)在25C与水互溶辛醇-水中分配系数的对数-1注:空气中的浓度换算：1ppm=1.2mg/m3(25°C)甲醛激性的，令人窒息的象干草和麦秆一样的气味。味阈值和嗅阈值分别为50和25mg/L1.2主要用途甲醛主要的工业用途是用于脲一甲醛、酚类、三聚氰胺、季戊四醇和聚缩醛树脂的生产：它的第二大用途是用于很多种有机物的工业合成中。甲醛还可用在化妆品、杀菌剂、纺织品和香水中。其10%浓度的水溶液俗称“福尔马林”.是动物、植物的防腐保鲜剂3分析方法用2,4-二硝基苯肼衍生，固液萃取后，HPLC测定.检测限6.2yg/L。2环境水平及人体摄入途径2.1空气甲通过塑料及合成树脂胶液进入空气。在空气中的低含量也由从化石燃料衍生的碳-氢化合物的光氧化产生。空气中典型浓度为几腿/m3。吸烟者会摄入高浓度的甲醛。2水饮用水中甲醛的来源主要是工业废水的排放和水中天然有机物（腐殖质）在臭氧化，氯化过程中氧化的产物。水中有机物通过热解可产生一定量的甲醛。Yamada等人研究指出加热会使水中甲醛含量增加，在通常的饮用水中甲醛含量为0—24.Opg/L,煮沸后浓度增加为18.0--73.5^g/L，而经臭氧处理的表面水，煮沸前为10・O--110卩g/L，煮沸后增至21.O-243pg/L,有关矿泉水中甲醛含量问题也有报导。甲醛也会从聚缩醛树脂的水道配件溶淋下来.3动物实验1动物实验及机理摄入的甲醛易由胃肠道吸收。在对皮肤的研究中，猴子皮肤对甲醛的吸收力比大鼠和几内亚猪要差。吸收后的甲醛主要分布于肌肉，少量则分布于肠、肝及其它组织中。甲醛能很快的被氧化成甲酸；而随后再氧化成的二氧化碳和水的氧化在猴子中要比在大鼠中慢。在大鼠中的其它代谢产物还有N,N'二羟甲基脲和N-羟甲基脲。代谢产物最后经尿、粪便及呼吸排出，代谢产物的相对量取决于甲醛的摄入途径。在大鼠和狗饮用含甲醛的水或食用含甲醛的食物的实验中.高剂量会引起一些组织病理学上的变化。生殖、胚胎毒性和致畸性在小鼠和小猎犬的怀孕期食用含甲醛的食物.没有发现致畸性-其幼鼠的生长发育能力也未受影响。而雄性大鼠一次性摄入甲醛含量按体重计为100--200mg/kg的食物，其精子出现异常。3.2致突变性和致癌性甲醛在生物体外试验中对原核及真核细胞都有致突变作用。在果蝇中也表现出基因毒性。甲醛易与蛋白质、RNA和单链DNA结合，导致DNA一蛋白质的交叉结合和单链DNA的断链。甲醛还容易与细胞中的大分子发生化学反应。在大鼠体内，甲醛可以增加DNA的合成以及上皮细胞的微核和细胞核的畸形。没有证据证明从口摄入甲醛会导致癌症。在大鼠每天饮用一定甲醛浓度的水的实验中。甲醛的摄入对肿瘤的发病率没有影响。但会产生一些组织病理学方面的变化。还没有证据证明甲醛能通过大鼠的皮肤产生致癌性或诱导肿瘤。有证据表明在大鼠和小鼠中，对甲醛气体的摄入（呼吸）可以刺激鼻的上皮细胞而产生致癌性。4对人体的影响皮肤接触甲醛气体会导致皮肤受刺激和过敏性皮炎。存在于水过滤系统中的甲醛可能对透析病人引起溶血性贫血症。有证据证明人体通过呼吸摄入的甲醛是致癌的。对工厂工人长期接触甲醛气体后死亡率的流行病学研究表明，肺癌发病率的轻微增加与甲醛摄入并没有关系。鼻咽癌也是应该注意的症状，但还是与甲醛无关。但经常暴露在甲醛环境中会产生一些如眼炎、鼻炎及呼吸道炎症等多种疾病。Kilburn等人研究了甲醛对神经行为功能的影响。长期（14-30年）使用甲醛、福尔马林可导致中枢神经系统功能的丧失。Norbaeck等人调查了气喘状况及室内空气的关系，指出甲醛和挥发性有机物含量偏高是导致气喘等症状的原因。Godish描述了与甲醛暴露水平有关的16种症状，包括眼炎、嗓子发干、流鼻涕、咳嗽、窦炎、窦感染、头痛、乏力、压抑、失眠、出疹鼻血、恶心、腹泻、胸痛和腹痛等。已有足够的证据表明甲醛对动物是强有力的致癌物。Marsh等人的研究表明长期接触甲醛使肺癌的发病率增加1.6倍。Andjelkovish等人调查发现在铸铁厂工人中，呼吸系统的病变及死亡与甲醛暴露水平没有直接联系。由于甲醛的毒害作用和致癌作用，因此在与其接触时应严格控制在动物试验和人体试验浓度容许范围之内。5分析方法由于甲醛在周围环境中广泛存在，对人体的潜在危害较大，因而测试技术的进展有着十分重要的意义。常用的测试方法有光谱分析法、液相色谱、气相色谱、离子色谱、比色法、极谱法和荧光分析法等。wHO推荐饮用水中的甲醛常用高效液相色谱法检测，用与2,4-二硝基肼的衍生物和液一固抽提。引人注目的是，近年来现场快速检测技术有了较大发展。Nakano采用检测试纸来测定甲醛的含量。Wang等人试制了一次使用的安培型甲醛传感器。Peat等人推出甲醛的半导体金属氧化物传感器检测器，其敏感材料为锌和锡的氧化物。从实验室到现场实地监测.这是测试方法的发展趋势，但灵敏度还有待提高。为了准确的检测水中甲醛，还可以采用下列方法测定：该方法选用以2.4-二硝基苯肼(2.4-DNPH)作为衍生剂，三氯甲烷为萃取剂，用气相色谱氢火焰离子化检测器测定。本方法选择性好、灵敏度高、操作简便快捷，不受其它物质的干扰，为水环境中甲醛的监测分析提出一个较为理想的方法。6国内外标准及限值现有国内外关于甲醛的有关标准值国内外关于甲醛的水质标准值单位：mg/L略基于对人和试验动物通过吸入接触甲醛所进行的研究，IARC将甲醛归类为第2A组。有证据表明甲醛经□摄入是不致癌的。WHO水质准则（1998基于TDI给出甲醛的指标值。从对大鼠进行的2年的研究得出的NOAEL为15mg/kg体重每天，结合不确定度为100同种和异种的差别），算出其TDI为150ug/kg体重。不考虑从其它家用水的接触途径如淋浴等吸入的甲醛的潜在致癌性，将TDI的20%分配给饮用水，得出甲醛的指标值为900M/Lo我们也据此推荐的饮用水中甲醛的指导值为900u/LChemicalAbstractNumber(CAS#)50000SynonymsFormaldehydeMethanalMethyleneoxideFormalinAnalyticalMethodsEPAMethod554EPAMethod8315MolecularFormulaCH2OUseDISINFECTING DWELLINGS, SHIPS,STORAGEHOUSES, UTENSILS,CLOTHES; GERMICIDE &FUNGICIDE FOR PLANTS &VEGETABLES;DESTROYING FLIES&OTHER INSECTS;MFRPHENOLIC RESINS, ARTIFICIAL SILK &CELLULOSEESTERS,DYES, ORGCHEM,GLASSMIRRORS, EXPLOSIVES; IMPROVINGFASTNESSOFDYES ONFABRICS; MORDANTING &WATERPROOFING FABRICS; PRESERVING &COATINGRUBBERLATEX;INPHOTOGRAPHYFORHARDENINGGELATINPLATES&PAPERS;TONINGGELATIN-CHLORIDEPAPERS;CHROMEPRINTING&DEVELOPING;TORENDERCASEIN,ALBUMIN&GELATININSOL;INCHEMANALYSIS;TOPREVENTMILDEW&SPELTINWHEAT&ROTINOATS;FUMIGANT FIXATION OF HISTOLOGICALSPECIMENS &INALTERATION OFBACTERIAL

TOXINSTOTOXOIDSFORVACCINES.SOLN,USPASGERMICIDEMAINLYUSEDIN2-8%CONCNTODISINFECTINANIMATEOBJECTS.Otherimportantusesineludewood-industryproducts,moldingcmpd,foundryresins,adhesivesforinsulation,slow-releasefertilizers,themanufactureofpermanent-pressfinishesofcellulosefabrics,andformaldehyde-basedtextilefinishes.Inmanufacturingfattyamidesandinpreciousmetalrecovery.CHEMINTFORPHENOLIC,POLYACETAL&MELAMINERESINSCHEMINTFORACETYLENICCHEMS-ESP,1,4-BUTANEDIOLCHEMINTFORPOLYOLS-EG,PENTAERYTHRITOLCHEMINTFORHEXAMETHYLENETETRAMINECHEMINTFORMETHYLENEDIANILINE(PRECURSOROFMETHYLENEDIANILINE)CHEMINTFORPYRIDINECHEMS&NITROPARAFFINDERIVSCOMPONENTOFDYES&DRILLINGMUDSASSTARCHPRESERVATIVEEMBALMINGAGENTCHEMINTFORRESORCINOL-FORMALDEHYDERESINSCHEMINTFORANILINE-FORMALDEHYDERESINSCHEMINTFORRUBBER-PROCESSINGCHEMSSEWAGETREATMENTAGENTCHEMINTFORSYNTHETICTANNINGAGENTSCOMPONENTOFTRIOXANEFUELTABLETSCHEMINTFORHERBICIDES&FERTILIZERCOATINGSCHEMINTFORPHARMACEUTICALS&ELASTOMERICSEALANTSChemicalintermediateforexplosivesandbactericides.Soilsterilantinmushroomhousesbeforeplanting.ConsumptionPatternsThelargestuseofformaldehydeisinthemanufactureofaminoandphenolicresins,accountingforabout55%ofthetotaldemand.Woodproductsaccountforabout36%ofthetotalformaldehydedemand,withparticleboard(chipsandsawdustwithresinbinder)first,andplywoodsecond.Approx80%oftheslow-releasefertilizermarketisbasedonurea-formaldehyde-containing products. Themanufactureof ethylenediaminetetraacetic acidconsumesabout75%oftheformaldehydeusedinthesynthesisofchelatingagents.Theother25%isusedtoproducenitriloaceticacid,primarilyforexport.Aminoresinsincludingurea&melamine,7.50X105tons.Aminoresinsmolding5.9X104tons;phenolicresins6.50X105tons&phenolicmoldingresins

6.6X104tons;fertilizers1.80X105tons;textilefinishes6.0X104tons;acetalresins1.80X105tons;butanediol2.00X105tons;pentaerythritol1.80X105tons;pyridines4.0X104tons;methylenediphenylisocyanate6.5X104tons;trimethylolpropane3.5X104tons;&hexamine1.50X105tons(as37%formaldehyde, 1978). CHEM INT FORUREA-FORMALDEHYDERESINS,26.5%;CHEMINTFORPHENOLICRESINS,19.6%;CHEMINTFORACETYLENICCHEMS,8.4%;CHEMINTFORPOLYACETALRESINS,7.9%;CHEMINTFORPENTAERYTHRITOL,6.7%;CHEMINTFORHEXAMETHYLENETETRAMINE,5.5%;CHEMINTFORUREA-FORMALDEHYDECONCENTRATES,5.2%;CHEMINTFORMETHYLENEDIANILINE,3.9%;CHEMINTFORMELAMINERESINS,3.6%;CHEMINTFORCHELATINGAGENTS,2.8%;OTHER,9.9% (1981).Worldwidedemandforformaldehydein1976wasestimatedtobeabout7.5X106tonsor60%capacity.During1985resinsgoingintoadhesivesandplasticsamounttomorethan60%ofdemandmostoftherestofformaldehydedemandisforuseasachemicalintermediate.Urea-formaldehyderesins,27%;phenolicresins,21%;butanediol,9%;polyacetalresins,9%;pentaerythritol,7%;hexamine,7%;urea-formaldehydeconcentrates,6%;melamine,4%;MDI,4%;other,includingexports,6%(1984).CHEMICALPROFILE:Formaldehyde.Ureaformaldehyderesins,27%;phenolicresins,21%;acetylenicchemicals,11%;polyacetalresins,8%;pentaerythritol,7%;hexamine,5.5%;urealformaldehydeconcentrates,5.5%;melamineresins,3.8%;MDI,4.7%;miscellaneous,5%.CHEMICALPROFILE:Formaldehyde.Demand:1985:5.8billionlb;1986:6billionlb;1990/projected/:6.63billionlb.CHEMICALPROFILE:Formaldehyde.Urea-formaldehyderesins,25%;phenolicresins,22%;polyacetalresins,9%;pentaerythritol,7%;hexamine,6%;urea-formaldehydeconcentrates,6%;MDI,5%;melamineresins,4%;miscellaneous,5%.CHEMICALPROFILE:Formaldehyde.Demand:6.73billionlb;1989:6.5billionlb;1993/projected/:7.6billionlb.(Includesexportsbutnotimports,bothofwhicharenegligible.Lastyear,exportstotaled19millionlb,and

importstotaled11millionlb.)ApparentColorClear,water-white,veryslightlyacid,gasorliquid.;Formaldehydesolutionisaclear,colorlessornearlycolorlessliquidOdorPUNGENTSUFFOCATINGODOR;Irritatingodor.LiquidBoilingPoint-19.5DEGCMeltingPoint-92DEGCMolecularWeight30.03Density1.067(AIR=1)OdorThresholdConcentration0.5to1.0ppmDetection:media=water:4.99x101ppmChemicallypureDetection:media=water:2.50x101ppmPuritynotspecifiedRecognition:media=air:1.00ppmChemicallypureOdorlow:1.4700mg/cum;Odorhigh:73.5000mg/cumSensitivityDataContactwiththeskincausesirritation,tanningeffect,andallergicsensitization.Contactwitheyescausesirritation,itching,&lacrimation.EnvironmentalImpactFormaldehydeisproducedinlargequantities(5.7billionlbin1983)primarilyforuseinthemanufactureofresinsandasachemicalintermediate.Muchofthisuseiscaptiveandnotreleasedintotheenvironment.Mostoftheformaldehydeenteringtheenvironmentisproduceddirectlyorindirectlyincombustionprocesses.Theindirectproductionisderivedfromthephotochemicaloxidationintheatmospherebysunlightofhydrocarbonsorotherformaldehydeprecusorsthathavebeenreleasedfromcombustionprocesses.Thistremendousinputofformaldehydeisremovedbydirectphotolysisandoxidationbyphotochemicallyproducedhydroxylradicals(half-lifeafewhours).Additionalquantitiesareremovedbydrydeposition,rainorbydissolvingintheoceanandothersurfacewaters.Intheaqueouscompartmentbiodegradationtakesplaceinafewdays.Humanexposuretoformaldehydeisfromambientairinheavytraffic,particularlyduringphotochemicalsmogepisodes,occupationalatmosphereswhereresinsareusedorwhereformaldehydeisusedasafumigant,disinfectant,embalmingfluid,etc.Homes,particularlyenergyefficientones,canhavehighlevelsofformaldehydefromstovesandtheemissionofthegas

frominsulation,furniture,resin-coatedrugsandotherfabrics.EnvironmentalFateTERRESTRIALFATE:Whenreleasedonsoil,aqueoussolutionscontainingformaldehydewillleachthroughthesoil.Whileformaldehydeisbiodegradableunderbothaerobicandanaerobicconditions,itsfateinsoilisunknown.AQUATICFATE:Whenreleasedintowater,formaldehydewillbiodegradetolowlevelsinafewdays.Littleadsorptiontosedimentwouldbeexpectedtooccur.Innutrient-enrichedseawaterthereisalonglagperiod(approximately40hr)priortomeasurablelossofaddedformaldehydebypresumablybiologicalprocessess.Itsfateingroundwaterisunknown.ATMOSPHERICFATE:Formaldehydeisreleasedtotheatmosphereinlargeamountsandformedintheatmospherebythephotooxidationofhydrocarbons.Thisinputiscounterbalaneedbyseveralimportantremovalpaths.Itbothphotolyzesandreactsrapidlywithreactivefreeradicals,principallyhydroxylradicals,whichareformedinthesunlight-irradiatedatmosphere.Thehalf-lifeinthesunlittroposphereisafewhours.Reactionwithnitrateradicals,insignificantduringtheday,maybeanimportantremovalmechanismatnight.Theinitialoxidationproduct,formicacid,isacomponentofacidrain.Becauseofitshighsolubilitytherewillbeefficienttransferintorainandsurfacewaterwhichmaybeanimportantsink.Onemodelpredictsdrydepositionandwetr