Particulate PAH Emissions from Residential Biomass Combustion: Time-Resolved Analysis with Aerosol Mass Spectrometry

Time-resolved emissions of particulate polycyclic aromatic hydrocarbons (PAHs) and total organic particulate matter (OA) from a wood log stove and an adjusted pellet stove were investigated with high-resolution time-of-flight aerosol mass spectrometry (ANIS). The highest OA emissions were found during the addition of log wood on glowing embers, that is, slow burning pyrolysis conditions. These emissions contained about 1% PAHs (of OA). The highest PAH emissions were found during fast burning under hot air starved combustion conditions, in both stoves. In the latter case, PAHs contributed up to 40% of OA, likely due to thermal degradation of other condensable species. The distribution of PAHs was also shifted toward larger molecules in these emissions. ANIS signals attributed to PAHs were found at molecular weights up to 600 Da. The vacuum aerodynamic size distribution was found to be bimodal with a smaller mode (D-va similar to 200 nm) dominating under hot air starved combustion and a larger sized mode dominating under slow burning pyrolysis (D-va similar to 600 nm). Simultaneous reduction of PAHs, OA and total particulate matter from residential biomass combustion may prove to be a challenge for environmental legislation efforts as these classes of emissions are elevated at different combustion conditions

Policiklički 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 lebdećih čestica 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 određene su gravimetrijski, dok je analiza policikličkih aromatskih ugljikovodika (PAU) rađena tekućinskom kromatografijom visoke djelotvornosti (HPLC) s fluorescentnim detektorom. Mjereni su sljedeći 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 više od onih na mjernome mjestu B, dok su u srpnju na oba mjerna mjesta bile vrlo slične. Srednja vrijednost koncentracije BaP izmjerenog u travnju na mjernome mjestu A bila je viša 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 granične vrijednosti (1 ng m-3) i tolerantne vrijednosti (1 ng m-3, Uredba iz 2005.), pa možemo zaključiti da je zrak u okolici plinskog polja Molve tijekom istraživanog razdoblja bio prve kategorije kakvoće

Acute Cardiovascular Effects of Controlled Exposure to Dilute Petrodiesel and Biodiesel Exhaust in Healthy Volunteers: A Crossover Study

Abstract Background Air pollution derived from combustion is associated with considerable cardiorespiratory morbidity and mortality in addition to environmental effects. Replacing petrodiesel with biodiesel may have ecological benefits, but impacts on human health remain unquantified. The objective was to compare acute cardiovascular effects of blended and pure biodiesel exhaust exposure against known adverse effects of petrodiesel exhaust (PDE) exposure in human subjects. In two randomized controlled double-blind crossover studies, healthy volunteers were exposed to PDE or biodiesel exhaust for one hour. In study one, 16 subjects were exposed, on separate occasions, to PDE and 30% rapeseed methyl ester biodiesel blend (RME30) exhaust, aiming at PM10 300 μg/m3. In study two, 19 male subjects were separately exposed to PDE and exhaust from a 100% RME fuel (RME100) using similar engine load and exhaust dilution. Generated exhaust was analyzed for physicochemical composition and oxidative potential. Following exposure, vascular endothelial function was assessed using forearm venous occlusion plethysmography and ex vivo thrombus formation was assessed using a Badimon chamber model of acute arterial injury. Biomarkers of inflammation, platelet activation and fibrinolysis were measured in the blood. Results In study 1, PDE and RME30 exposures were at comparable PM levels (314 ± 27 μg/m3; (PM10 ± SD) and 309 ± 30 μg/m3 respectively), whereas in study 2, the PDE exposure concentrations remained similar (310 ± 34 μg/m3), but RME100 levels were lower in PM (165 ± 16 μg/m3) and PAHs, but higher in particle number concentration. Compared to PDE, PM from RME had less oxidative potential. Forearm infusion of the vasodilators acetylcholine, bradykinin, sodium nitroprusside and verapamil resulted in dose-dependent increases in blood flow after all exposures. Vasodilatation and ex vivo thrombus formation were similar following exposure to exhaust from petrodiesel and the two biodiesel formulations (RME30 and RME100). There were no significant differences in blood biomarkers or exhaled nitric oxide levels between exposures. Conclusions Despite differences in PM composition and particle reactivity, controlled exposure to biodiesel exhaust was associated with similar cardiovascular effects to PDE. We suggest that the potential adverse health effects of biodiesel fuel emissions should be taken into account when evaluating future fuel policies. Trial registration ClinicalTrials.gov, NCT01337882 /NCT01883466. Date of first enrollment March 11, 2011, registered April 19, 2011, i.e. retrospectively registered

The Victorian Newsletter (Fall 1993)

The Victorian Newsletter is sponsored for the Victorian Group of Modern Language Association by Western Kentucky University and is published twice annually.Eros and Logos in Some Fairy Tales by Oscar Wilde: A Jungian Interpretation / Clifton Snider -- "The Central Truth": Phallogocentrism in Aurora Leigh / Patricia Thomas Srebnik -- "I Magnify My Office": Christina Rossetti's Authoritative Voice in Her Devotional Prose / Joel Westerholm -- The Sterile Star of Venus: Swinburne's Dream of Flight / Peter Anderson -- Bringing to Earth the "Good Angel of the Race" / Michael Schiefelbein -- The Flawed Craft of A. E. Housman / A. R. Coulthard -- The Physiological Determinism Debate in Oscar Wilde's The Picture of Dorian Gray / Terri A. Hasseler -- Overdetermined Allegory in Jekyll and Hyde / Cyndy Hendershot -- Books Received -- Group New