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Characteristics and cellular effects of ambient particulate matter from Beijing Texto completo
2014
Lu, Yan | Su, Shu | Jin, Wenjie | Wang, Bin | Li, Ning | Shen, Huizhong | Li, Wei | Huang, Ye | Chen, Han | Zhang, Yanyan | Chen, Yuanchen | Lin, Nan | Wang, Xilong | Tao, Shu
In vitro tests using human adenocarcinomic alveolar epithelial cell line A549 and small mouse monocyte-macrophage cell line J774A.1 were conducted to test toxicity of six PM (particulate matter) samples from Beijing. The properties of the samples differ significantly. The production of inflammatory cytokine (TNF-α for J774A.1) and chemokine (IL-8 for A549) and the level of intracellular reactive oxygen species (ROS) were used as endpoints. There was a positive correlation between water soluble organic carbon and DTT-based redox activity. Both cell types produced increased levels of inflammatory mediators and had higher level of intracelllar ROS, indicating the presence of PM-induced inflammatory response and oxidative stress, which were dose-dependent and significantly different among the samples. The releases of IL-8 from A549 and TNF-α from J774A.1 were significantly correlated to PM size, Zeta potential, endotoxin, major metals, and polycyclic aromatic hydrocarbons. No correlation between ROS and these properties was identified.
Mostrar más [+] Menos [-]Dose-response relationship between polycyclic aromatic hydrocarbon metabolites and risk of diabetes in the general Chinese population Texto completo
2014
Yang, Liangle | Zhou, Yun | Sun, Huizhen | Lai, Hanpeng | Liu, Chuanyao | Yan, Kai | Yuan, Jing | Wu, Tangchun | Chen, Weihong | Zhang, Xiaomin
The incidence of diabetes is increasing rapidly in Chinese population, and it has been postulated that environmental factors may play a role in the etiology of diabetes. Therefore, we aimed to investigate the association between PAHs exposure and risk of diabetes in a community-based population of 2824 participants with completed questionnaires, measurements of biochemical indices, and urinary PAHs metabolites. We found that elevated urinary PAHs metabolites were associated, in a dose-dependent manner, with increased risk of diabetes. Particularly, these associations were more evident in subjects who were female, less than 55 years old, nonsmokers, and normal weight. In addition, there was a modest improvement in diabetes discrimination of prediction models when incorporating certain PAHs metabolites into conventional risk factors (CRF). Overall, our data suggested that there may be a dose-dependent relationship between PAHs metabolites and risk of diabetes among general Chinese population.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons in surface soil across the Tibetan Plateau: Spatial distribution, source and air–soil exchange Texto completo
2014
Wang, Chuanfei | Wang, Xiaoping | Gong, Ping | Yao, Tandong
There are limited data on polycyclic aromatic hydrocarbons (PAHs) in both the atmosphere and soil of the Tibetan Plateau (TP). Concentrations of PAHs were therefore measured in 13 XAD resin-based passive air samplers and 41 surface (0–5 cm) soil samples across the TP. The average concentration of atmospheric PAHs was 5.55 ng/m3, which was lower than that reported for other background areas, but higher than the Arctic. Concentrations in the soils fell in a wide range from 5.54 to 389 ng/g, with an average of 59.9 ng/g. Elevation was found to play an important role in determining the spatial distribution of soil PAHs. The air–soil exchange state showed that the soils of the TP will likely remain as a sink for high molecular weight PAHs, but may become a potential “secondary source” for low molecular weight PAHs.
Mostrar más [+] Menos [-]Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures Texto completo
2014
Ortuño, Nuria | Moltó, Julia | Conesa, Juan A. | Font, Rafael
Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures Texto completo
2014
Ortuño, Nuria | Moltó, Julia | Conesa, Juan A. | Font, Rafael
Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant worldwide. A detailed examination of the degradation products emitted during thermal decomposition of TBBPA is presented in the study. Runs were performed in a laboratory furnace at different temperatures (650 and 800 °C) and in different atmospheres (nitrogen and air). More than one hundred semivolatile compounds have been identified by GC/MS, with special interest in brominated ones. Presence of HBr and brominated light hydrocarbons increased with temperature and in the presence of oxygen. Maximum formation of PAHs is observed at pyrolytic condition at the higher temperature. High levels of 2,4-, 2,6- and 2,4,6- bromophenols were found. The levels of polybrominated dibenzo-p-dioxins and furans have been detected in the ppm range. The most abundant isomers are 2,4,6,8-TeBDF in pyrolysis and 1,2,3,7,8-PeBDF in combustion. These results should be considered in the assessment of thermal treatment of materials containing brominated flame retardants.
Mostrar más [+] Menos [-]Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures Texto completo
2014
Ortuño García, Nuria | Moltó Berenguer, Julia | Conesa, Juan A. | Font, Rafael | Universidad de Alicante. Departamento de Ingeniería Química | Residuos, Pirólisis y Combustión
Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant worldwide. A detailed examination of the degradation products emitted during thermal decomposition of TBBPA is presented in the study. Runs were performed in a laboratory furnace at different temperatures (650 and 800 °C) and in different atmospheres (nitrogen and air). More than one hundred semivolatile compounds have been identified by GC/MS, with special interest in brominated ones. Presence of HBr and brominated light hydrocarbons increased with temperature and in the presence of oxygen. Maximum formation of PAHs is observed at pyrolytic condition at the higher temperature. High levels of 2,4-, 2,6- and 2,4,6- bromophenols were found. The levels of polybrominated dibenzo-p-dioxins and furans have been detected in the ppm range. The most abundant isomers are 2,4,6,8-TeBDF in pyrolysis and 1,2,3,7,8-PeBDF in combustion. These results should be considered in the assessment of thermal treatment of materials containing brominated flame retardants. | Support for this work was provided by the Generalitat Valenciana (Spain), research project Prometeo/2009/043/FEDER, and by the Spanish Ministry of Education and Science, research project CTQ2008-05520.
Mostrar más [+] Menos [-]Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement Texto completo
2014
Mahler, Barbara J. | Van Metre, Peter C. | Foreman, William T.
Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement.
Mostrar más [+] Menos [-]Source apportionment of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons by a PMF receptor model. Assessment of potential risk for human health Texto completo
2014
Callén, María Soledad | Iturmendi, Amaia | López, José Manuel
One year sampling (2011–2012) campaign of airborne PM2.5-bound PAH was performed in Zaragoza, Spain. A source apportionment of total PAH by Positive Matrix Factorization (PMF) was applied in order to quantify potential PAH pollution sources.Four sources were apportioned: coal combustion, vehicular emissions, stationary emissions and unburned/evaporative emissions. Although Directive 2004/107/EC was fulfilled regarding benzo(a)pyrene (BaP), episodes exceeding the limit value of PM2.5 according to Directive 2008/50/EC were found. These episodes of high negative potential for human health were studied, obtaining a different pattern for the exceedances of PM2.5 and the lower assessment threshold of BaP (LATBaP). In both cases, stationary emissions contributed majority to total PAH. Lifetime cancer risk exceeded the unit risk recommended by the World Health Organization for those episodes exceeding the LATBaP and the PM2.5 exceedances for the warm season. For the cold season, the risk was higher for the LATBaP than for the PM2.5 exceedances.
Mostrar más [+] Menos [-]Air pollution effects on fetal and child development: A cohort comparison in China Texto completo
2014
Tang, Deliang | Li, Ting Yu | Chow, Judith C. | Kulkarni, Sanasi U. | Watson, John G. | Ho, Steven Sai Hang | Quan, Zhang Y. | Qu, L.R. | Perera, Frederica
In Tongliang, China, a coal-fired power plant was the major pollution source until its shutdown in 2004. We enrolled two cohorts of nonsmoking women and their newborns before and after the shutdown to examine the relationship between prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) and fetal and child growth and development. PAHs were used to measure exposure to air pollution generated by the power plant. Using PAH–DNA adduct levels as biomarkers for the biologically effective dose of PAH exposure, we examined whether PAH–DNA adduct levels were associated with birth outcome, growth rate, and neurodevelopment. Head circumference was greater in children of the second cohort, compared with the first (p = 0.001), consistent with significantly reduced levels of cord blood PAH–DNA adducts in cohort II (p < 0.001) and reduced levels of ambient PAHs (p = 0.01).
Mostrar más [+] Menos [-]Combining measurements and modelling to quantify the contribution of atmospheric fallout, local industry and road traffic to PAH stocks in contrasting catchments Texto completo
2014
Gateuille, David | Evrard, Olivier | Lefevre, Irène | Moreau-Guigon, Elodie | Alliot, Fabrice | Chevreuil, Marc | Mouchel, J.-M. (Jean-Marie)
Various sources supply PAHs that accumulate in soils. The methodology we developed provided an evaluation of the contribution of local sources (road traffic, local industries) versus remote sources (long range atmospheric transport, fallout and gaseous exchanges) to PAH stocks in two contrasting subcatchments (46–614 km²) of the Seine River basin (France). Soil samples (n = 336) were analysed to investigate the spatial pattern of soil contamination across the catchments and an original combination with radionuclide measurements provided new insights into the evolution of the contamination with depth. Relationships between PAH concentrations and the distance to the potential sources were modelled. Despite both subcatchments are mainly rural, roadside areas appeared to concentrate 20% of the contamination inside the catchment while a local industry was found to be responsible for up to 30% of the stocks. Those results have important implications for understanding and controlling PAH contamination in rural areas of early-industrialized regions.
Mostrar más [+] Menos [-]Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas – Characterization by multivariate analysis Texto completo
2014
Foan, L. | Leblond, S. | Thöni, L. | Raynaud, C. | Santamaría, J.M. | Sebilo, M. | Simon, V.
Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas – Characterization by multivariate analysis Texto completo
2014
Foan, L. | Leblond, S. | Thöni, L. | Raynaud, C. | Santamaría, J.M. | Sebilo, M. | Simon, V.
Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100–700 ng g−1, as well as δ13C values of −32 to −29‰ and δ15N values of −11 to −3‰ were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4–6 aromatic rings) content and δ13C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain.
Mostrar más [+] Menos [-]Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas - Characterization by multivariate analysis Texto completo
2014
Foan, Louise | Leblond, Sébastien | Thöni, Lotti | Raynaud, Christine | Santamaria, Jesus Miguel | Sebilo, Mathieu | Simon, Valérie
Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100-700 ng g-1, as well as δ13C values of -32 to -29‰ and δ15N values of -11 to -3‰ were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4-6 aromatic rings) content and δ13C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain.
Mostrar más [+] Menos [-]Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas - Characterization by multivariate analysis Texto completo
2014
Foan, Louise | Leblond, Sébastien | Thöni, Lotti | Raynaud, Christine | Santamaria, Jesus Miguel | Sebilo, Mathieu | Simon, Valérie | Chimie Agro-Industrielle (CAI) ; Institut National de la Recherche Agronomique (INRA)-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques (ENSIACET) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Origine, structure et évolution de la biodiversité (OSEB) ; Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS) | FUB - Research Group for Environmental Monitoring (SWITZERLAND) ; FUB - Research Group for Environmental Monitoring (SWITZERLAND) | Laboratorio Integrado de Calidad Ambiental - LICA (Pamplona, Spain) ; Universidad de Navarra [Pamplona] (UNAV) | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | France by the Agence de l'Environnement et de la Maitrise de l'Energie (ADEME) ; Spain by the Foundation of the University of Navarra (FUNA) ; CAN Foundation ; Switzerland by the Federal Office for the Environment (FOEN) ;Communaute de Travail des Pyrenees/Communidad de Trabajo de los Pirineos (CTP)
International audience | Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100-700 ng g-1, as well as δ13C values of -32 to -29‰ and δ15N values of -11 to -3‰ were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4-6 aromatic rings) content and δ13C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain.
Mostrar más [+] Menos [-]Coal-tar-based sealcoated pavement: A major PAH source to urban stream sediments Texto completo
2014
Witter, Amy E. | Nguyen, Minh H. | Baidar, Sunil | Sak, Peter B.
We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (∼1303 km2) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69–0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use.
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