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Abstract: In this work, 24-h PM10 samples were collected in Rio de Janeiro, Brazil, and analysed for trace elements (Cd, Ce, Cu, La, Mo, Ni, Pb, Pd, Rh, Sb and Sn). The sampling was carried out at five locations (Bonsucesso; Centro, downtown city; Copacabana; Nova Iguaçu and Sumaré) with different traffic densities and anthropogenic activities. An analytical method based on the EPA method for the determination of trace elements in airborne particulate matter (PM), using ultrasonic-assisted extraction and inductively coupled plasma mass spectrometry (ICP-MS) was applied. Our results suggest that vehicular traffic is the most important source of environmental pollution at the studied sites. The presence of Mo, Pd and Rh in the analysed filters reflects an additional source of pollution caused by the erosion and deterioration of automotive catalytic converters. [Copyright &y& Elsevier]

Abstract: The concentrations of trace metals and polycyclic aromatic hydrocarbons (PAHs) adsorbed to total suspended particulate (TSP) and finer fractions of airborne particulate matter (PM) were determined from a site in the centre of Athens (Greece), which is characterized by heavy local traffic and is densely populated, during the winter and summer periods in 2003–2004. Also, we collected and analyzed samples of diesel and gasoline exhaust particles from local vehicles (buses, taxis and private cars) and from chimney exhaust of residential central heating appliances. A seasonal effect was observed for the size distribution of aerosol mass, with a shift to larger fine fractions in winter. The most commonly detected trace metals in the TSP and PM fractions were Fe, Pb, Zn, Cu, Cr, V, Ni and Cd and their concentrations were similar to levels observed in heavily polluted urban areas from local traffic and other anthropogenic emissions. Analysis of 16 PAHs bound to PM showed that they are mostly traffic related. In general, the fine particulate PAHs concentrations were higher than coarse particles. The most common PAHs in PM10.2 and PM2.1 were pyrene, phenanthrene, acenapthylene and fluoranthene, which are associated with diesel and gasoline exhaust particles. The results of this study underlined the importance of local emission sources, especially vehicular traffic, central heating and other local anthropogenic emissions. Compared with other big cities, Athens has much higher levels of airborne particles, especially of the finer fractions PM10 and PM2.5, correlated with traffic-related air pollution. [Copyright &y& Elsevier]

Abstract: 9,10-Phenanthrenequinone (PQ), one of the components of atmospheric pollutants, has potent harmful effects on human health. PQ in airborne particulates collected in Nagasaki city was determined by HPLC with fluorescence derivatization. PQ extracted from airborne particulates using methanol was derivatized with benzaldehyde in the presence of ammonium acetate to give a fluorescent compound. The average concentration (mean±SD, n =52) of PQ found in airborne particulates collected from July 1997 to June 1998 was 0.287±0.128ngm−3. Concentrations of PQ in winter were higher than those in summer. In a weekly variation study, PQ concentrations were higher during weekdays and lower at weekend. The levels of PQ were obviously correlated with those of phenanthrene (PH) that is considered as a parent compound of PQ. This observation suggested that PQ was emitted into the atmosphere from the same source as PH, or PQ was converted from PH in the atmosphere. [Copyright &y& Elsevier]

Abstract: The size distributions of airborne particulate matter (PM) and associated heavy metals Pb, Cd, Ni, Cr, V, Mn, Cu and Fe in different inhalable fractions (<0.8μm, 0.8–1.3μm, 1.3–2.7μm, 2.7–6.7μm and >6.7μm) were determined at a traffic-orientated urban site in the city of Thessaloniki, northern Greece. The airborne PM displayed a bimodal distribution with most of the mass (52%) contained in the submicron size range (<0.8μm) and an additional minor mode (20%) in the coarse size fraction (>6.7μm). Characteristic size distributions of heavy metals allowed identification of three main behavioral types: (a) metals whose mass was resided mainly within the accumulation mode (Pb,Cd), (b) those which were distributed between fine, intermediate and coarse modes (Ni,Cu,Mn), and (c) those which were mainly found within particles larger than 2.7μm in diameter (Fe). The mean mass median aerodynamic diameter (MMAD) of PM was found at 0.85±0.71μm, while the mean MMADs of heavy metals followed the order Pb (0.96±0.71μm)<Cd (1.14±0.82μm)<V (1.38±0.63μm)<Ni (1.45±0.88μm)<Cu (2.04±0.77μm)<Mn (2.61±1.23μm)<Cr (2.91±1.40μm)<Fe (3.82±0.88μm). The measured distributions are believed to result from a combination of processes including local anthropogenic and natural sources, such as traffic, industrial emissions and resuspension of road dust. [Copyright &y& Elsevier]

Concentrations and profiles of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were analyzed in airborne particulate matter (PM) samples collected from high-traffic roads in Hanoi urban area. Levels of PAHs and Me-PAHs ranged from 210 to 660 (average 420) ng/m3 in total PM, and these pollutants were mainly associated with fine particles (PM 2.5) rather than coarser ones (PM > 10 and PM 10). Proportions of high-molecular-weight compounds (i.e., 5- and 6-ring) increased with decreasing particle size. Benzo[b+k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[ghi]perylene were the most predominant compounds in the PM 2.5 samples. In all the samples, Me-PAHs were less abundant than unsubstituted PAHs. The PAH-CALUX assays were applied to evaluate aryl hydrocarbon receptor (AhR) ligand activities in crude extracts and different fractions from the PM samples. Benzo[a]pyrene equivalents (BaP-EQs) derived by the PAH-CALUX assays for low polar fractions (mainly PAHs and Me-PAHs) ranged from 300 to 840 ng/m3, which were more consistent with theoretical values derived by using PAH-CALUX relative potencies (270–710 ng/m3) rather than conventional toxic equivalency factor-based values (22–69 ng/m3). Concentrations of PAHs and Me-PAHs highly correlated with bioassay-derived BaP-EQs. AhR-mediated activities of more polar compounds and interaction effects between PAH-related compounds were observed. By using PAH-CALUX BaP-EQs, the ILCR values ranged from 1.0 × 10−4 to 2.8 × 10−4 for adults and from 6.4 × 10−5 to 1.8 × 10−4 for children. Underestimation of cancer risk can be eliminated by using effect-directed method (e.g., PAH-CALUX) rather than chemical-specific approach. [Display omitted] • PAHs, Me-PAHs, and AhR ligand activities were measured in airborne PM samples. • Pollutant concentrations and induced toxicities were mainly associated with PM 2.5. • 5- and 6-ring compounds (e.g., Bb + kF, IP, BP) dominated PAH patterns in PM 2.5. • Significant gaps between conventional and bioassay-derived BaP-EQs were found. • Application of effect-directed method can reduce risk underestimation of PAHs. [ABSTRACT FROM AUTHOR]

Atmospheric coarse particulate matter (PM 10) enriched with heavy metal(loid)s could pose potentially significant health risk to humans, while accurate health risk assessment calls for characterization of their bioaccessibility, besides the total contents. The health risk of major toxic heavy metal(loid)s in the PM 10 from four large cities in northern China via inhalation was investigated based on their total contents and bioaccessibility. The annual mean concentrations of PM-bound Zn, As, Pb, and Mn in the atmosphere of the four cities were 650, 305, 227, and 177 ng⋅m−3, respectively. The levels of heavy metal(loid)s in the PM 10 were generally higher in winter but lower in summer in all four cities, which resulted primarily from the emissions associated with coal combustion for district and household heating and the unfavorable meteorological conditions in winter. The bioaccessibility of heavy metal(loid)s in the PM 10 ranged from 0.9 to 48.7%, following the general order of Mn > Co > Ni > Cd > Cu > As > Cr > Zn > Pb. Based on their total contents in the PM 10 , most heavy metal(loid)s posed significant public health risk via inhalation exposure in the four cities. However, after accounting for the bioaccessibility of metal(loid)s, the non-carcinogenic risk of most metal(loid)s was negligible, except for As in the PM 10 of Jinzhong, while only the carcinogenic risk posed by Cr and As in the PM 10 exceeded the acceptable level. These findings demonstrate the importance of characterizing the bioaccessibility of airborne PM-bound heavy metal(loid)s in health risk assessment and could guide the on-going efforts on reducing the public health risk of PM 10 in northern China. [Display omitted] • Contents and bioaccessibility of metal(loid)s in PM 10 from four cities were analyzed. • Zn, As, Pb, and Mn had much higher abundance than the other metal(loid)s in the PM 10. • The bioaccessibility of heavy metal(loid)s in the PM 10 varied largely (0.9–48.7%). • Health risk would be over-estimated based on total contents of metal(loid)s in PM 10. • PM-bound As posed the most significant public health risk via inhalation exposure. [ABSTRACT FROM AUTHOR]

The skin is one of the main organs exposed to airborne particulate matter (PM), which may contain various pollutants linked to a wide range of adverse health endpoints. In the present work, we analyzed the proinflammatory and oxidative effects of some PM components leading to inflammatory responses, cell proliferation or cell death. We investigated four redox-active chemicals, such as Cu (II) metal and quinones generated from polycyclic aromatic hydrocarbons (PAHs), i.e., 9,10 phenanthrenequinone and isomers 1,2 and 1,4 naphthoquinone. We performed in vitro biological tests on human keratinocyte (HaCaT) cells and also acellular assays based on the oxidation of dithiothreitol and ascorbic acid, antioxidants to assess the oxidative potential (OP). We found that treated keratinocytes showed increased activation of the redox-sensitive transcription factor NFκB and increased transcript levels of the NFκB-dependent gene IL8. Moreover, the treatment with Cu(II) and quinones increased the activities and the expression of genes involved in the redox response, SOD1 and GPX, suggesting that PM components induced cellular damage due to redox imbalances. Finally, we found alteration of the mitochondrial ultrastructure and increased apoptosis after 24 h of treatment. The results presented suggest that all of the analyzed pollutant components are able to modulate similar signal transduction pathways, resulting in activation of inflammatory processes in the skin, followed by oxidative damage. Altogether these observations indicate that exposure of skin to air pollutants modifies the redox equilibrium of keratinocytes, which could explain the increased skin damage observed in populations that live in high-pollution cities. Image 1 • Comparison between AA and DDT and in vivo cells oxidation in the presence of PM components. • Activation of the redox transcription factor NFκB on keratinocytes treated with PM components. • Cu (II) and quinones increased the activities and expression of IL8, SOD1 and GPX genes. • Keratinocytes mitochondrial alteration and apoptosis was increased after treatment. • Exposure of skin to air pollutants can modifies the redox equilibrium of keratinocytes. [ABSTRACT FROM AUTHOR]