項目解讀甲醛

《生活飲用水衛(wèi)生標(biāo)準(zhǔn)》GB5749-2006項目解讀甲醛1概述1.1基本性質(zhì)美國化學(xué)文摘(CA)編號500-00-0IUPAC對甲醛的命名為“methanal”分子式化0理化性質(zhì)自然狀態(tài)無色氣體沸點。C-19.2熔點。C-118相對密度1.04(空氣為1)蒸氣壓52.6kPa(-33C)水溶性(g/i)在25C與水互溶辛醇-水中分配系數(shù)的對數(shù)-1注:空氣中的濃度換算：1ppm=1.2mg/m3(25°C)甲醛激性的，令人窒息的象干草和麥稈一樣的氣味。味閾值和嗅閾值分別為50和25mg/L1.2主要用途甲醛主要的工業(yè)用途是用于脲一甲醛、酚類、三聚氰胺、季戊四醇和聚縮醛樹脂的生產(chǎn)：它的第二大用途是用于很多種有機(jī)物的工業(yè)合成中。甲醛還可用在化妝品、殺菌劑、紡織品和香水中。其10%濃度的水溶液俗稱“福爾馬林”.是動物、植物的防腐保鮮劑3分析方法用2,4-二硝基苯肼衍生，固液萃取后，HPLC測定.檢測限6.2yg/L。2環(huán)境水平及人體攝入途徑2.1空氣甲通過塑料及合成樹脂膠液進(jìn)入空氣。在空氣中的低含量也由從化石燃料衍生的碳-氫化合物的光氧化產(chǎn)生?？諝庵械湫蜐舛葹閹淄?m3。吸煙者會攝入高濃度的甲醛。2水飲用水中甲醛的來源主要是工業(yè)廢水的排放和水中天然有機(jī)物（腐殖質(zhì)）在臭氧化，氯化過程中氧化的產(chǎn)物。水中有機(jī)物通過熱解可產(chǎn)生一定量的甲醛。Yamada等人研究指出加熱會使水中甲醛含量增加，在通常的飲用水中甲醛含量為0—24.Opg/L,煮沸后濃度增加為18.0--73.5^g/L，而經(jīng)臭氧處理的表面水，煮沸前為10?O--110卩g/L，煮沸后增至21.O-243pg/L,有關(guān)礦泉水中甲醛含量問題也有報導(dǎo)。甲醛也會從聚縮醛樹脂的水道配件溶淋下來.3動物實驗1動物實驗及機(jī)理攝入的甲醛易由胃腸道吸收。在對皮膚的研究中，猴子皮膚對甲醛的吸收力比大鼠和幾內(nèi)亞豬要差。吸收后的甲醛主要分布于肌肉，少量則分布于腸、肝及其它組織中。甲醛能很快的被氧化成甲酸；而隨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。在大鼠中的其它代謝產(chǎn)物還有N,N'二羥甲基脲和N-羥甲基脲。代謝產(chǎn)物最后經(jīng)尿、糞便及呼吸排出，代謝產(chǎn)物的相對量取決于甲醛的攝入途徑。在大鼠和狗飲用含甲醛的水或食用含甲醛的食物的實驗中.高劑量會引起一些組織病理學(xué)上的變化。生殖、胚胎毒性和致畸性在小鼠和小獵犬的懷孕期食用含甲醛的食物.沒有發(fā)現(xiàn)致畸性-其幼鼠的生長發(fā)育能力也未受影響。而雄性大鼠一次性攝入甲醛含量按體重計為100--200mg/kg的食物，其精子出現(xiàn)異常。3.2致突變性和致癌性甲醛在生物體外試驗中對原核及真核細(xì)胞都有致突變作用。在果蠅中也表現(xiàn)出基因毒性。甲醛易與蛋白質(zhì)、RNA和單鏈DNA結(jié)合，導(dǎo)致DNA一蛋白質(zhì)的交叉結(jié)合和單鏈DNA的斷鏈。甲醛還容易與細(xì)胞中的大分子發(fā)生化學(xué)反應(yīng)。在大鼠體內(nèi)，甲醛可以增加DNA的合成以及上皮細(xì)胞的微核和細(xì)胞核的畸形。沒有證據(jù)證明從口攝入甲醛會導(dǎo)致癌癥。在大鼠每天飲用一定甲醛濃度的水的實驗中。甲醛的攝入對腫瘤的發(fā)病率沒有影響。但會產(chǎn)生一些組織病理學(xué)方面的變化。還沒有證據(jù)證明甲醛能通過大鼠的皮膚產(chǎn)生致癌性或誘導(dǎo)腫瘤。有證據(jù)表明在大鼠和小鼠中，對甲醛氣體的攝入（呼吸）可以刺激鼻的上皮細(xì)胞而產(chǎn)生致癌性。4對人體的影響皮膚接觸甲醛氣體會導(dǎo)致皮膚受刺激和過敏性皮炎。存在于水過濾系統(tǒng)中的甲醛可能對透析病人引起溶血性貧血癥。有證據(jù)證明人體通過呼吸攝入的甲醛是致癌的。對工廠工人長期接觸甲醛氣體后死亡率的流行病學(xué)研究表明，肺癌發(fā)病率的輕微增加與甲醛攝入并沒有關(guān)系。鼻咽癌也是應(yīng)該注意的癥狀，但還是與甲醛無關(guān)。但經(jīng)常暴露在甲醛環(huán)境中會產(chǎn)生一些如眼炎、鼻炎及呼吸道炎癥等多種疾病。Kilburn等人研究了甲醛對神經(jīng)行為功能的影響。長期（14-30年）使用甲醛、福爾馬林可導(dǎo)致中樞神經(jīng)系統(tǒng)功能的喪失。Norbaeck等人調(diào)查了氣喘狀況及室內(nèi)空氣的關(guān)系，指出甲醛和揮發(fā)性有機(jī)物含量偏高是導(dǎo)致氣喘等癥狀的原因。Godish描述了與甲醛暴露水平有關(guān)的16種癥狀，包括眼炎、嗓子發(fā)干、流鼻涕、咳嗽、竇炎、竇感染、頭痛、乏力、壓抑、失眠、出疹鼻血、惡心、腹瀉、胸痛和腹痛等。已有足夠的證據(jù)表明甲醛對動物是強(qiáng)有力的致癌物。Marsh等人的研究表明長期接觸甲醛使肺癌的發(fā)病率增加1.6倍。Andjelkovish等人調(diào)查發(fā)現(xiàn)在鑄鐵廠工人中，呼吸系統(tǒng)的病變及死亡與甲醛暴露水平?jīng)]有直接聯(lián)系。由于甲醛的毒害作用和致癌作用，因此在與其接觸時應(yīng)嚴(yán)格控制在動物試驗和人體試驗濃度容許范圍之內(nèi)。5分析方法由于甲醛在周圍環(huán)境中廣泛存在，對人體的潛在危害較大，因而測試技術(shù)的進(jìn)展有著十分重要的意義。常用的測試方法有光譜分析法、液相色譜、氣相色譜、離子色譜、比色法、極譜法和熒光分析法等。wHO推薦飲用水中的甲醛常用高效液相色譜法檢測，用與2,4-二硝基肼的衍生物和液一固抽提。引人注目的是，近年來現(xiàn)場快速檢測技術(shù)有了較大發(fā)展。Nakano采用檢測試紙來測定甲醛的含量。Wang等人試制了一次使用的安培型甲醛傳感器。Peat等人推出甲醛的半導(dǎo)體金屬氧化物傳感器檢測器，其敏感材料為鋅和錫的氧化物。從實驗室到現(xiàn)場實地監(jiān)測.這是測試方法的發(fā)展趨勢，但靈敏度還有待提高。為了準(zhǔn)確的檢測水中甲醛，還可以采用下列方法測定：該方法選用以2.4-二硝基苯肼(2.4-DNPH)作為衍生劑，三氯甲烷為萃取劑，用氣相色譜氫火焰離子化檢測器測定。本方法選擇性好、靈敏度高、操作簡便快捷，不受其它物質(zhì)的干擾，為水環(huán)境中甲醛的監(jiān)測分析提出一個較為理想的方法。6國內(nèi)外標(biāo)準(zhǔn)及限值現(xiàn)有國內(nèi)外關(guān)于甲醛的有關(guān)標(biāo)準(zhǔn)值國內(nèi)外關(guān)于甲醛的水質(zhì)標(biāo)準(zhǔn)值單位：mg/L略基于對人和試驗動物通過吸入接觸甲醛所進(jìn)行的研究，IARC將甲醛歸類為第2A組。有證據(jù)表明甲醛經(jīng)□攝入是不致癌的。WHO水質(zhì)準(zhǔn)則（1998基于TDI給出甲醛的指標(biāo)值。從對大鼠進(jìn)行的2年的研究得出的NOAEL為15mg/kg體重每天，結(jié)合不確定度為100同種和異種的差別），算出其TDI為150ug/kg體重。不考慮從其它家用水的接觸途徑如淋浴等吸入的甲醛的潛在致癌性，將TDI的20%分配給飲用水，得出甲醛的指標(biāo)值為900M/Lo我們也據(jù)此推薦的飲用水中甲醛的指導(dǎo)值為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