8 research outputs found
Razine i profili policikliÄkih aromatskih ugljikovodika u zraku Zagreba u sezoni loženja
Samples of suspended particulate matter, collected at four sites in Zagreb during the heating season were analysed for the content of polycyclic aromatic hydrocarbons. Data were analysed with special reference to indicators of car traffic contribution the BghiPer/BaP and Cor/BaP ratios. Taking 1.5 as a borderline value for the BghiPer/BaP ratio, a significant influence of car traffic on air pollution by polycyclic aromatic hydrocarbons was noticed at a site close to a petrol station. Our data were compared with the BghiPer/BaP and Cor/BaP ratios from other countries. A similar relationship of the ratios between urban and traffic near sites was obtained.Uzorci lebdeÄih Äeslica, sakupljeni na Äetiri mjerne stanice U Zagrebu u sezoni loženja, analizirani su na sadržaj policikliÄkih aromatskih ugljikovodika. Podaci su razmatrani s posebnim osvrtom na pokazatelje doprinosa prometa: omjeri BghiPer/BaP i Kor/BaP. UzevÅ”i 1,5 kao graniÄnu vrijednost za omjer BghiPer/BaP utvrÄen je znaÄajan utjecaj prometa na oneÄiÅ”Äenje zraka policikliÄkim aromatskim ugljikovodicima na stanici n blizini benzinske crpke. Usporedba naÅ”ih podataka s omjerima BghiPer/BaP i Kur/BaP u drugim zemljama pokazuje sliÄne odnose izmeÄu ta dva omjera u opÄoj atmosferi i u blizini toka prometa
The determination of sulphur dioxide by the acidimetric method in the presence of ammonia
Ispitana je moguÄnost primjene raÄunske korekcije na rezultate odreÄivanja sumpor-dioksida u zraku u prisutnosti amonijaka. Pokazano je da se sumpor-dioksid i amonijak mogu djelotvorno sakupiti iz zraka u istu otopinu (0,06%-tni H202). Ako se slobodni sumpor-dioksid ili amonijak odredi titracijom, a ukupni amonijak u istom uzorku kolorimetrijski, može se iz razlike izraÄunati vezani sumpor-dioksid. Metoda je dala dobre rezultate na eksperimentalnim uzorcima, a uspjeÅ”no je primijenjena i u praksi.A possibility for correcting sulphur dioxide concentrations obtained by acidimetric titration in the presence of ammonia has been evaluated. It has been shown that both sulphur dioxide and ammonia can be efficiently collected in the same absorbing solution (0.06% H202). If the excess of ammonia or sulphur dioxide is determined by titration and total ammonia by the colorimetric method the bound sulphur dioxide can be calculated from the difference. The method has given good results with experimental samples and has been successfully applied in the field
PolicikliÄki aromatski ugljikovodici u zraku okolice plinskog polja Molve
Small-volume air samples (~7 m3 per 24 h) of airborne PM10 particle fraction were collected on quartz fibre filters at two measuring sites in the vicinity of the gas field Molve in April and July 2006. It took five to seven days for each sample to collect and one month to collect five to seven samples. Mass concentrations of PM10 fractions were determined by gravimetry while PAHs were analysed using a HPLC with a fluorescent detector. The analysis included fluoranthene (Flu), pyrene (Pyr), benzo(a)anthracene (BaA), chrysene (Cry), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), benzo(ghi)perylene (BghiP) and indene(1,2,3-cd)pyrene (Ind). Average concentrations of all PAHs in April at site A were slightly higher than at site B while in July they were lower and similar on both sites. Average BaP concentration measured at site A in April was 0.156 ng m-3 and at site B 0.129 ng m-3, while July BaP averages were 0.022 ng m-3 at both sites. In both months, the mass concentration of BaP was lower than the limit value (1 ng m-3) and well below the tolerant value (2 ng m-3) set by a Croatian regulation of 2005. This suggests that the air near gas field Molve was of acceptable quality in respect to BaP at the time of the measurement.Uzorci PM10 frakcije lebdeÄih Äestica skupljani su prosisavanjem malog volumena zraka (~7 m3 za 24 h) kroz filtre od kvarcnih vlakana. Svaki je uzorak skupljan tijekom pet do sedam dana na dva mjerna mjesta u okolici plinskog polja Molve. Uzorkovanje je provedeno tijekom travnja i srpnja 2006. godine. Masene koncentracije PM10 frakcije odreÄene su gravimetrijski, dok je analiza policikliÄkih aromatskih ugljikovodika (PAU) raÄena tekuÄinskom kromatografijom visoke djelotvornosti (HPLC) s fluorescentnim detektorom. Mjereni su sljedeÄi PAU: fluoranten, piren, benzo(a)antracen, krizen, benzo(b)fluoranten, benzo(k)fluoranten, benzo(a)piren, benzo(ghi)perilen i indeno(1,2,3-cd)piren. Srednje vrijednosti masenih koncentracija svih PAU u travnju na mjernome mjestu A bile su neznatno viÅ”e od onih na mjernome mjestu B, dok su u srpnju na oba mjerna mjesta bile vrlo sliÄne. Srednja vrijednost koncentracije BaP izmjerenog u travnju na mjernome mjestu A bila je viÅ”a od vrijednosti izmjerene na mjernome mjestu B. U srpnju su srednje vrijednosti bile znatno niže i na oba mjerna mjesta iznosile su 0.022 ng m-3. Iz rezultata dobivenih mjerenjem vidljivo je da je koncentracija benzo(a)pirena bila znatno niža od graniÄne vrijednosti (1 ng m-3) i tolerantne vrijednosti (1 ng m-3, Uredba iz 2005.), pa možemo zakljuÄiti da je zrak u okolici plinskog polja Molve tijekom istraživanog razdoblja bio prve kategorije kakvoÄe
Polycyclic Aromatic Hydrocarbons in Air
PolicikliÄki aromatski ugljikovodici (PAU) spojevi su koji se sastoje od dva ili viÅ”e kondenziranih aromatskih prstenova. Nastaju prilikom nepotpunog izgaranja ili pirolize organskih tvari. Dokazano je da neki PAU imaju kancerogena, a neki mutagena svojstva, pa je stoga potrebno kontinuirano pratiti koncentracije PAU u zraku, vodi i tlu, te pokuÅ”ati sanirati izvore PAU. PAU s dva ili tri aromatska prstena postojani su u plinovitoj fazi, dok se PAU s viÅ”e aromatskih prstenova nalaze u zraku uglavnom vezani na Äestice. Visoke koncentracije PAU prisutne su u atmosferi urbanih podruÄja, a najviÅ”e su zimi kada su pojaÄane emisije iz kuÄnih ložiÅ”ta. U ljetno doba koncentracije su niže jer je veÄina policikliÄkih aromatskih ugljikovodika nestabilna na visokim temperaturama, a osim toga dolazi do njihove oksidacije i fotooksidacije. Metode mjerenja PAU u zraku ukljuÄuju uzorkovanje prosisavanjem na filterski papir ili kruti adsorbens, ekstrakciju i kromatografsku analizu. U ovom radu prikazani su rezultati mjerenja benzo[a]pirena (BaP) kao glavnog predstavnika PAU na nekim lokacijama u svijetu. Razine BaP u svijetu usporeÄene su s rezultatima mjerenja provedenim do sada u Hrvatskoj.Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic compounds consisting of two or more condense aromatic rings. They are products of incomplete combustion or pyrolysis of organic matter. Because some PAHs such as Benzo[a]pyrene (BaP) are proven carcinogens and mutagens, it is necessary to continuously monitor their concentrations in the air, water, and soil. PAHs with two or three aromatic rings are stable in the gas phase, while most PAHs with five or more aromatic rings bond to particles. Higher concentrations of PAHs are present in the atmosphere of urban areas, mostly in the winter, due to heating. In the summer, these concentrations drop because most PAHs are unstable at high temperatures and break down by oxidation and photooxidation. Measurements of PAHs in the air include sampling on the filter paper or solid adsorbent, extraction, and chromatographic analysis. This review presents the measurements of BaP in some locations in the world and compares them with the findings in Croatia
Spatial and seasonal variability of the mass concentration and chemical composition of PM2.5 in Poland
Concentrations and profiles of polycyclic aromatic hydrocarbons in Zenica by season
Mjereno je 12 policikliÄkih aromatskih ugljikovodika u uzorcima lebdeÄih Äestica uzorkovanim u srediÅ”njem dijelu Zenice svaki treÄi ili Äetvrti dan tijekom cijele godine. Koncentracije su posebno visoke zimi, kada su uz stalnu industrijsku emisiju prisutne i emisije iz kuÄnih ložiÅ”ta, a zbog klimatskih i orografskih uvjeta ÄeÅ”Äe dolazi do temperaturne inverzije. Profili, tj. omjeri policikliÄkih aromatskih ugljikovodika prema benzo-a-pirenu ne variraju mnogo u ovisnosti o godiÅ”njem dobu osim fluorantena i pirena. Srednje godiÅ”nje vrijednosti mjerenih policikliÄkih aromatskih ugljikovodika su viÅ”e (omjer zimskih i ljetnih koncentracija niži) u odnosu na podruÄja gdje ne postoji stalan izvor njihovih emisija.Twelve polycyclic aromatic hydrocarbons were measured in samples of airborne particles collected in the town of Zenica in the Republic of Bosnia and Herzegovina every third or fourth day throughout the year. The concentrations were especially high in winter when in addition to permanent industrial emissions those from individual heating systems were also present and when owing to climatic and orographical circumstances temperature inversions occurred more frequently. The profiles of polycyclic aromatic hydrocarbons i.e. their ratios to benzo-a-pyrene did not demonstrate great seasonal variations with the exception of fluoranthene and pyrene. The mean annual concentrations (winter to summer concentration ratios) were higher than in the areas where there was no permanent source of emissions