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Oil sands development and its impact on atmospheric wet deposition of air pollutants to the Athabasca Oil Sands Region, Alberta, Canada Texto completo
2015
Lynam, Mary M. | Dvonch, J Timothy | Barres, James A. | Morishita, Masako | Legge, Allan | Percy, Kevin
Characterization of air pollutant deposition resulting from Athabasca oil sands development is necessary to assess risk to humans and the environment. To investigate this we collected event-based wet deposition during a pilot study in 2010–2012 at the AMS 6 site 30 km from the nearest upgrading facility in Fort McMurray, AB, Canada. Sulfate, nitrate and ammonium deposition was (kg/ha) 1.96, 1.60 and 1.03, respectively. Trace element pollutant deposition ranged from 2 × 10−5 - 0.79 and exhibited the trend Hg < Se < As < Cd < Pb < Cu < Zn < S. Crustal element deposition ranged from 1.4 × 10−4 – 0.46 and had the trend: La < Ce < Sr < Mn < Al < Fe < Mg. S, Se and Hg demonstrated highest median enrichment factors (130–2020) suggesting emissions from oil sands development, urban activities and forest fires were deposited. High deposition of the elements Sr, Mn, Fe and Mg which are tracers for soil and crustal dust implies land-clearing, mining and hauling emissions greatly impacted surrounding human settlements and ecosystems.
Mostrar más [+] Menos [-]Source contributions and regional transport of primary particulate matter in China Texto completo
2015
Hu, Jianlin | Wu, Li | Zheng, Bo | Zhang, Qiang | He, Kebin | Chang, Qing | Li, Xinghua | Yang, Fumo | Ying, Qi | Zhang, Hongliang
A source-oriented CMAQ was applied to determine source sector/region contributions to primary particulate matter (PPM) in China. Four months were simulated with emissions grouped to eight regions and six sectors. Predicted elemental carbon (EC), primary organic carbon (POC), and PPM concentrations and source contributions agree with measurements and have significant spatiotemporal variations. Residential is a major contributor to spring/winter EC (50–80%), POC (60%–90%), and PPM (30–70%). For summer/fall, industrial contributes 30–50% for EC/POC and 40–60% for PPM. Transportation is more important for EC (20–30%) than POC/PPM (<5%). Open burning is important in summer/fall of Guangzhou and Chongqing. Dust contributes to 1/3–1/2 in spring/fall of Beijing, Xi'an and Chongqing. Based on sector–region combination, local residential/transportation and residential/industrial from Heibei are major contributors to spring PPM in Beijing. In summer/fall, local industrial is the largest. In winter, residential/industrial from local and Hebei account for >90% in Beijing.
Mostrar más [+] Menos [-]Exposure to household endotoxin and total and allergen-specific IgE in the US population Texto completo
2015
Min, Kyoung-Bok | Min, Chin-yŏng
Background: Although endotoxin has strong pro-inflammatory properties, endotoxin-allergy relationship in adults and children have been inconsistent. Objectives: We investigated the association between household endotoxin levels and total immunoglobulin E (IgE) or specific IgE in the US general population, classified into three age ranges: children/adolescent, adults, and older adults. Methods: We analyzed the 2005–2006 National Health and Nutrition Examination Surveys. A total of 5220 participants for whom serum IgE and household endotoxin data were available was included in the analyses. Results: Exposure to endotoxin reduced the risk for allergic sensitization, especially in specific IgE to plants (OR in Quartile 3 = 0.58; 95% CI = 0.44–0.76) and pets (OR in Quartile 3 = 0.62; 95% CI = 0.41–0.92), for children/adolescents. In contrast, the risk among adults and older adults increased with increasing endotoxin levels. Conclusions: Our findings suggest that the effect of endotoxin on allergic reaction is likely to depend on age.
Mostrar más [+] Menos [-]Application of chemometric analysis and self Organizing Map-Artificial Neural Network as source receptor modeling for metal speciation in river sediment Texto completo
2015
Pandey, Mayank | Pandey, Ashutosh Kumar | Mishra, Ashutosh | Tripathi, B.D.
Present study deals with the river Ganga water quality and its impact on metal speciation in its sediments. Concentration of physico-chemical parameters was highest in summer season followed by winter and lowest in rainy season. Metal speciation study in river sediments revealed that exchangeable, reducible and oxidizable fractions were dominant in all the studied metals (Cr, Ni, Cu, Zn, Cd, Pb) except Mn and Fe. High pollution load index (1.64–3.89) recommends urgent need of mitigation measures. Self-organizing Map-Artificial Neural Network (SOM-ANN) was applied to the data set for the prediction of major point sources of pollution in the river Ganga.
Mostrar más [+] Menos [-]Induction of c-Jun by air particulate matter (PM10) of Mexico city: Participation of polycyclic aromatic hydrocarbons Texto completo
2015
Salcido-Neyoy, Martha Estela | Sánchez-Pérez, Yesennia | Osornio-Vargas, Alvaro Román | Gonsebatt, Maria Eugenia | Meléndez-Zajgla, Jorge | Morales-Bárcenas, Rocío | Petrosyan, Pavel | Molina-Servin, Edith Danny | Vega, Elizabeth | Manzano-León, Natalia | García-Cuellar, Claudia M.
The carcinogenic potential of urban particulate matter (PM) has been partly attributed to polycyclic aromatic hydrocarbons (PAHs) content, which activates the aryl hydrocarbon receptor (AhR). Here we report the effect of PM with an aerodynamic size of 10 μm (PM10) on the induction of AhR pathway in A549 cells, evaluating its downstream targets CYP1B1, IL-6, IL-8 and c-Jun. Significant increases in CYP1B1 protein and enzyme activity; IL-6 and IL-8 secretion and c-Jun protein were found in response to PM10. The formation of PAH-DNA adducts was also detected. The involvement of AhR pathway was confirmed with Resveratrol as AhR antagonist, which reversed CYP1B1 and c-Jun induction. Nevertheless, in IL-6 and IL-8 secretion, the Resveratrol was ineffective, suggesting an effect independent of this pathway. Considering the role of c-Jun in oncogenesis, its induction by PM may be contributing to its carcinogenic potential through induction of AhR pathway by PAHs present in PM10.
Mostrar más [+] Menos [-]Development of water quality criteria for phenanthrene and comparison of the sensitivity between native and non-native species Texto completo
2015
Wu, Jiang-Yue | Yan, Zhen-Guang | Liu, Zheng-Tao | Liu, Ji-dong | Liang, Feng | Wang, Xiao-Nan | Wang, Weili
Phenanthrene (PHE) is a priority polycyclic aromatic hydrocarbon (PAH) which is toxic to aquatic organisms. However, there has been no paper dealing with water quality criteria (WQC) of PHE due to the shortage of toxicity data of different taxonomic levels. In the present study, toxicity data were obtained from 8 acute toxicity tests and 3 chronic toxicity tests using 8 Chinese native aquatic species from different taxonomic levels, and the water quality criteria was derived using 3 methods. Furthermore, differences of species sensitivity distributions (SSDs) between native and non-native species were compared. A criterion maximum concentration of 0.0514 mg/L and a criterion continuous concentration of 0.0186 mg/L were developed according to the US EPA guidelines. Finally, by using risk quotient (RQ) to assess the site-specific ecological risk in Liao River, the results indicated that the PHE might pose no risk to local aquatic species.
Mostrar más [+] Menos [-]Novel brominated flame retardants and dechlorane plus in Greenland air and biota Texto completo
2015
Vorkamp, Katrin | Bossi, Rossana | Rigét, Frank F. | Skov, Henrik | Sonne, Christian | Dietz, Rune
Following the ban of polybrominated diphenyl ethers, other halogenated flame retardants (FRs) might be used increasingly. This study has analyzed hexabromocyclododecane (HBCD), 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and dechlorane plus (DP) in Greenland air over the course of a year. Moreover, BTBPE, DPTE, DP, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), bis(2-ethylhexyl)tetrabromophthalate (TBPH) and decabromodiphenyl ethane (DBDPE) were analyzed in samples of polar bear, ringed seal, black guillemot and glaucous gull from Greenland. HBCD in air appeared low, while mean concentrations of syn- and anti-DP were 2.3 and 5.2 pg/m3, respectively. BTBPE and DPTE were undetectable in air. Detection frequencies in biota were <50% for BTBPE, TBPH and DBDPE, but near 100% for the remaining compounds. Ringed seals from East Greenland had highest mean concentrations of TBB, DPTE, syn- and anti-DP (1.02, 0.078, 0.096 and 0.42 ng/g wet weight, respectively). Our study documents the long-range transport and, to some extent, bioaccumulation of these novel FRs.
Mostrar más [+] Menos [-]Tenax as sorption sink for in vitro bioaccessibility measurement of polycyclic aromatic hydrocarbons in soils Texto completo
2015
Li, Chao | Cui, Xin−Yi | Fan, Ying−Ying | Teng, Ying | Nan, Zhong−Ren | Ma, Lena Q.
Physiologically based in vitro methods have been developed to measure bioaccessibility of organic contaminants in soils. However, bioaccessibility of hydrophobic organic contaminants (HOCs) can be underestimated by in vitro tests if gastrointestinal (GI) solution fails to provide sufficient sorption sink for HOCs. To circumvent this drawback, Tenax was included in GI solution as sorption sink to trap mobilized HOCs and maintain the desorption gradient between soil and GI solution. Polycyclic aromatic hydrocarbons (PAHs) were selected as target HOCs, and physiologically based extraction test (PBET) was selected as the in vitro method. Inclusion of Tenax in GI solution increased bioaccessibility of PAHs in five spiked soils from 8.25–20.8% to 55.7–65.9% and the bioaccessibility of PAHs in a field contaminated soil from 3.70–6.92% to 16.3–31.0%. Our results demonstrated the effectiveness of Tenax as sorption sink to enhance PAH mobilization in bioaccessibility measurement in soils.
Mostrar más [+] Menos [-]Positive relationship detected between soil bioaccessible organic pollutants and antibiotic resistance genes at dairy farms in Nanjing, Eastern China Texto completo
2015
Sun, Mingming | Ye, Mao | Wu, Jun | Feng, Yanfang | Wan, Jinzhong | Tian, Da | Shen, Fangyuan | Liu, Kuan | Hu, Feng | Li, Huixin | Jiang, Xin | Yang, Linzhang | Kengara, Fredrick Orori
Co-contaminated soils by organic pollutants (OPs), antibiotics and antibiotic resistance genes (ARGs) have been becoming an emerging problem. However, it is unclear if an interaction exists between mixed pollutants and ARG abundance. Therefore, the potential relationship between OP contents and ARG and class 1 integron-integrase gene (intI1) abundance was investigated from seven dairy farms in Nanjing, Eastern China. Phenanthrene, pentachlorophenol, sulfadiazine, roxithromycin, associated ARG genes, and intI1 had the highest detection frequencies. Correlation analysis suggested a stronger positive relationship between the ARG abundance and the bioaccessible OP content than the total OP content. Additionally, the significant correlation between the bioaccessible mixed pollutant contents and ARG/intI1 abundance suggested a direct/indirect impact of the bioaccessible mixed pollutants on soil ARG dissemination. This study provided a preliminary understanding of the interaction between mixed pollutants and ARGs in co-contaminated soils.
Mostrar más [+] Menos [-]Occurrence of venlafaxine, other antidepressants and selected metabolites in the Rhine catchment in the face of climate change Texto completo
2015
Schlüsener, Michael P. | Hardenbicker, Paulin | Nilson, Enno | Schulz, Manoj | Viergutz, Carsten | Ternes, Thomas A.
Fate and occurrence of 4 selective serotonin reuptake inhibitors, one serotonin-noradrenergic reuptake inhibitor and one noradrenergic-dopamineric reuptake inhibitor and their human metabolites were determined in a German municipal wastewater treatment plant as well as in the Rhine River and selected tributaries. The enantiomeric fractions of venlafaxine and its metabolites were not altered during wastewater treatment and were similar in all river samples underlining that no appreciable biodegradation occurs. In the Rhine catchment area highest concentrations were detected for venlafaxine, citalopram and their human metabolites. Projected future climate change would lead to an increased portion of treated wastewater in rivers due to reduced discharges during low flow situations by the end of the 21st century. However, the effect of climate change on the pattern and concentrations of antidepressants is predicted to be of minor importance in comparison to altered consumption quantities caused by demographic developments and changes in life styles.
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