council direct march biolog screen popul lead eec council european commun regard treati establish european econom commun articl thereof regard propos commiss regard opinion european parliament regard opinion econom social committe essenti task european econom commun promot commun harmoni develop econom activ continu balanc expans achiev combat pollut nuisanc improv qualiti life protect environ lead present caus contamin area environ substanc environment sourc lead make difficult determin total exposur individu pollut protect human health call accur monitor individu total lead absorpt biolog screen popul lead carri result screen evalu propos drawn desir lai technic procedur biolog refer level screen measur blood lead level mean assess quantiti lead recent receiv individu result exposur environment lead enzymat activ delta aminolevulin acid dehydratas alad indic supplementari test determin exposur lead programm action european commun environ coordin nation programm aim improv qualiti life prioriti investig lead adopt direct articl member state step appli common procedur biolog screen order assess exposur popul lead work environ articl common procedur applic restrict year base measur blood lead level indic supplementari test alad measur accord procedur laid annex ii iii oj oj oj articl condit biolog screen fix mean sampl analysi procedur frequenc sampl blood sampl carri volunt articl sampl carri group person urban area inhabit group person feasibl chosen peopl expos signific sourc lead pollut critic group determin compet author member state member state campaign number analys perform million inhabit articl sampl group refer articl carri campaign area investig period oper programm separ month campaign sampl necessarili person campaign articl assess result biolog screen purpos action provid articl blood lead level account relationship dose effect annex refer level maximum pb ml blood group peopl examin maximum pb ml blood group peopl examin maximum pb ml blood group peopl examin articl blood lead level determin member state inform commiss name laboratori take part biolog screen programm method analysi commiss conjunct member state organ inter comparison programm abovement laboratori particip commiss conjunct member state examin result programm view improv compar method analysi articl result analys refer level set articl exceed case member state check valid result action trace exposur sourc respons level exceed includ action individu blood lead level ml measur discret compet nation author articl month notif direct member state design compet nation author forward commiss data relat biolog screen popul group refer articl detail method analysi popul group examin area sampl complet anonym preserv person examin commiss member state agre procedur method data forward inform factor presum result refer level articl exceed compet nation author notifi commiss measur pursuant indent articl articl year commiss conven meet repres govern member state ensur implement biolog screen provis articl harmon analys carri compar examin inform facilit exchang inform member state result biolog screen measur pursuant articl articl basi inform collect pursuant articl commiss draw cooper compet nation author collat annual report implement programm forward member state council european parliament gener report end programm form basi draw propos take account progress made scientif technic knowledg articl member state measur enabl procedur laid direct enter forc month notif immedi inform commiss thereof articl direct address member state brussel march council presid benn annex relationship dose effect blood lead level assess result biolog screen base analysi scientif data toxic effect lead analysi take account normal variat biolog valu popul establish quasi quantit relationship dose effect relationship dose effect refer purpos direct decreas alad activ red corpuscl result exposur lead toler popul provid interfer haematopoiesi blood lead level ml decreas alad activ consid interfer haematopoiesi increas protoporphyrin content erythrocyt blood ppe interfer bodi iron synthesi haem increas ppe found blood lead level ml increas ppe due interfer glutathion synthesi toler small fraction popul slight result clinic symptom unaccept interfer glutathion synthesi found blood lead level ml signific increas excret delta aminolevulin acid urin alau signific sign disturb metabol porphyrin sign health impair statist signific increas alau begin found blood level ml annex ii correspond blood lead level enzymat activ purpos articl direct relationship blood lead level alad enzymat activ measur accord european standard method annex iii gt pic file quot quot gt alad valu measur significantli higher limit section popul confirmatori blood lead measur requir annex iii technic instruct measur alad activ european standard method determin activ delta aminolevulin acid dehydratas principl method adopt determin activ delta aminolevulin acid dehydratas base incub enzym excess delta aminolevulin acid substrat porphobilinogen pbg form length time mix modifi ehrlich reagent colour obtain measur white photomet quantiti porphobilinogen produc constitut measur alad activ method effect light recent experi shown pbg sensit light entir analysi conduct direct sunlight laboratori simpli exclud point analysi carri phase blood sampl preserv analysi sampl ml venou blood plastic syring lead stabil presenc dri heparin prepar immedi cool ºc sampl ml plastic tube lead stabil graduat marbourg type pipett sampl analyz hour chill sampl preserv ºc longer hour analysi sampl bath ic water minut note plastic includ polythen polystyren polypropylen preserv period hour ºc cautiou estim interv long sampl remov analysi point central laboratori blood sampl measur alad fourth blank phase haematocrit read read time blood sampl capillari method sampl sampl centrifug close end tube speed rev minut minut note read prefer case hour blood sampl microhaematocrit centrifug phase haemolysi blood sampl quot thaw quot ml distil water preheat ºc haemolys minut ºc prefer ml graduat pipett ad water mix shake sampl stage note decid water triton haemolysi haemolysi experi triton result consider slow alad activ account artifact phase addit ala solut haemolys prepar ala solut prepar hour heat solut ºc minut ad add ml solut haemolys prefer ml volumetr pipett mix note ph experi shown ph correl alad activ blood lead level normal popul obtain maximum activ rais ph activ measur fairli high phase prepar blank ml blood treat measur alad point ala solut ad place add ml tca hgcl solut ml ala solut proce measur alad add solut volumetr pipett note blank compar seri test blood sampl od obtain blank high oper repeat check phase incub minut ºc water bath incub time run addit ala solut note incub period minut chosen order increas alad activ natur mean phase lead artifici increas activ experi shown incub time activ ratio linear interv hour incub temperatur ºc practic reason phase halt pbg reaction add ml tca hgcl solut incub mixtur prefer ml volumetr pipett phase centrifug filtrat rev minut filtrat whatman paper equival acid resist note centrifug minut filtrat phase includ order avoid transfer pipett small particl surfac supernat liquid particl produc colour reaction ehrlich reagent number test shown inclus filtrat phase lead reproduc phase replac centrifug phase reaction ehrlich reagent mix ml supernat liquid ml modifi ehrlich reagent ml volumetr pipett vortex type mixer ensur mixtur homogen reaction continu minut measur extinct note obtain homogen mixtur import ensur filter supernat liquid mix ehrlich reagent phase ten extinct measur calibr spectrophotomet phenolphthalin solut basic buffer compar extinct measur sampl blank nm cm cell cm absorpt low phase eleven calcul enzym activ equat calcul enzym activ gt pic file quot quot gt od extinct measur incub time dilut factor molal extinct coeffici cm mol spectrophotometr correct coeffici note unit propos consist recommend intern union biochemistri enzym nomenclatur solut prepar ala solut solut na hpo dissolv ml distil water prefer deioniz solut nah po dissolv ml distil water ml solut ml solut give buffer sodium phosphat ph buffer strength prevent fluctuat ph solut undergo reaction mg ala hcl dissolv solut acid ph adjust basi solut volum made ml buffer solut sodium phosphat ph prepar solut ala tca hgcl solut hgcl dissolv ml trichloracet acid ehrlich reagent solut reagent dimethylaminobenzaldehyd pdmab hgcl dissolv ml glacial acet acid perchlor acid sg glacial acet acid prepar dissolv pdmab ml acet acid add ml perchlor acid ml hgcl solut mix cool make ml glacial acet acid graduat flask store dark bottl calibr commun level calibr carri year laboratori jointli appoint member state brown color appear point reagent discard