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Variations in concentrations and compositions of polycyclic aromatic hydrocarbons (PAHs) in coals related to the coal rank and origin Полный текст
2011
Laumann, S. | Micić, V. | Kruge, M.A. | Achten, C. | Sachsenhofer, R.F. | Schwarzbauer, J. | Hofmann, T.
The release of unburnt coal particles and associated polycyclic aromatic hydrocarbons (PAHs) may cause adverse impacts on the environment. This study assessed variations in the concentration and composition of PAHs in a set of fifty coal samples from eleven coal basins worldwide. The maximum PAH concentrations at high volatile bituminous rank were recorded in samples from a single basin. Considering the entire sample set, the highest PAH concentrations were in fact found outside of this rank range, suggesting that the maceral composition and thus the coal’s origin also influenced PAH concentrations. The examination of the PAH compositions revealed that alkylated 2–3 ring PAHs remain dominant compounds irrespective of coal rank or origin. Multivariate analysis based on PAH and maceral content, bulk and maturity parameters allowed the recognition of seven groups with different rank and origin within the coal sample set.
Показать больше [+] Меньше [-]Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss Полный текст
2011
Wang, M.Y. | Chen, A.K. | Wong, M.H. | Qiu, R.L. | Cheng, H. | Ye, Z.H.
Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg⁻¹ in soil) and a soil pot trial (control, 100 mg Cd kg⁻¹), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11–0.29 mg kg⁻¹) in a field soil, (2) grain Cd tolerance (34–113%) and concentrations (2.1–6.5 mg kg⁻¹) in a pot trial, and (3) rates of ROL (15–31 mmol O₂ kg⁻¹ root d.w. h⁻¹). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw.
Показать больше [+] Меньше [-]Fate and effects of anthropogenic chemicals in mangrove ecosystems: A review Полный текст
2011
Lewis, Michael | Pryor, Rachel | Wilking, Lynn
The scientific literature for fate and effects of non-nutrient contaminant concentrations is skewed for reports describing sediment contamination and bioaccumulation for trace metals. Concentrations for at least 22 trace metals have been reported in mangrove sediments. Some concentrations exceed sediment quality guidelines suggesting adverse effects. Bioaccumulation results are available for at least 11 trace metals, 12 mangrove tissues, 33 mangrove species and 53 species of mangrove-habitat biota. Results are specific to species, tissues, life stage, and season and accumulated concentrations and bioconcentration factors are usually low. Toxicity tests have been conducted with 12 mangrove species and 8 species of mangrove-related fauna. As many as 39 effect parameters, most sublethal, have been monitored during the usual 3 to 6 month test durations. Generalizations and extrapolations for toxicity between species and chemicals are restricted by data scarcity and lack of experimental consistency. This hinders chemical risk assessments and validation of effects-based criteria.
Показать больше [+] Меньше [-]Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences Полный текст
2011
Jerez, Silvia | Motas, Miguel | Palacios, María José | Valera, Francisco | Cuervo, José Javier | Barbosa, Andrés
Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences Полный текст
2011
Jerez, Silvia | Motas, Miguel | Palacios, María José | Valera, Francisco | Cuervo, José Javier | Barbosa, Andrés
Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adélie penguin collected in 8 locations throughout the Antarctic Peninsula (2006–2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 μg g⁻¹ dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 μg g⁻¹ dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine.
Показать больше [+] Меньше [-]Concentration of trace elements in feathers of three Antarctic penguins: Geographical and interspecific differences Полный текст
2011
Jerez, Silvia | Motas, Miguel | Palacios, María José | Valera, Francisco | Cuervo, José Javier | Barbosa, Andrés | Ministerio de Ciencia e Innovación (España) | European Commission
Antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. Concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and Pb were determinated by ICP-MS in feathers (n = 207 individuals) of gentoo, chinstrap and Adélie penguin collected in 8 locations throughout the Antarctic Peninsula (2006-2007). The highest levels of several elements were found in samples from King George Island (8.08, 20.29 and 1.76 μg g-1 dw for Cr, Cu and Pb, respectively) and Deception Island (203.13, 3.26 and 164.26 μg g-1 dw for Al, Mn and Fe, respectively), where probably human activities and large-scale transport of pollutants contribute to increase metal levels. Concentrations of Cr, Mn, Cu, Se or Pb, which are similar to others found in different regions of the world, show that some areas in Antarctica are not utterly pristine. © 2010 Published by Elsevier Ltd. | This study has been funded by the Spanish Ministry of Science and Innovation and European Regional Development Fund (grants CGL2004-01348, POL2006-05175 and CGL2007-60369). | Peer Reviewed
Показать больше [+] Меньше [-]A dynamic modelling approach for estimating critical loads of nitrogen based on plant community changes under a changing climate Полный текст
2011
Belyazid, Salim | Kurz, Dani | Braun, Sabine | Sverdrup, Harald | Rihm, Beat | Hettelingh, Jean-Paul
A dynamic model of forest ecosystems was used to investigate the effects of climate change, atmospheric deposition and harvest intensity on 48 forest sites in Sweden (n = 16) and Switzerland (n = 32). The model was used to investigate the feasibility of deriving critical loads for nitrogen (N) deposition based on changes in plant community composition. The simulations show that climate and atmospheric deposition have comparably important effects on N mobilization in the soil, as climate triggers the release of organically bound nitrogen stored in the soil during the elevated deposition period. Climate has the most important effect on plant community composition, underlining the fact that this cannot be ignored in future simulations of vegetation dynamics. Harvest intensity has comparatively little effect on the plant community in the long term, while it may be detrimental in the short term following cutting. This study shows: that critical loads of N deposition can be estimated using the plant community as an indicator; that future climatic changes must be taken into account; and that the definition of the reference deposition is critical for the outcome of this estimate.
Показать больше [+] Меньше [-]Soil intervention as a strategy for lead exposure prevention: The New Orleans lead-safe childcare playground project Полный текст
2011
Mielke, Howard W. | Covington, Tina P. | Mielke, Paul W., Jr | Wolman, Fredericka J. | Powell, Eric T. | Gonzales, Chris R.
The feasibility of reducing children’s exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14–3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2–26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 μg/m² (454 μg/ft²) range 603–56650 μg/m² (56–5263 μg/ft²) to a median of 398 μg/m² (37 μg/ft²) range 86–980 μg/m² (8–91 μg/ft²). Multi-Response Permutation Procedures indicate similar (P-values = 0.160–0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At ∼$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention.
Показать больше [+] Меньше [-]Traffic exposure in a population with high prevalence type 2 diabetes – Do medications influence concentrations of C-reactive protein? Полный текст
2011
Rioux, Christine L. | Tucker, Katherine L. | Brugge, Doug | Gute, David M. | Mwamburi, Mkaya
Type 2 Diabetes (T2D) and particulate air pollution are associated with inflammatory dysregulation. We assessed the modifying effects of diabetes medications on the association of C-reactive protein (CRP), a marker of inflammation, and traffic exposure in adults with T2D (n = 379). CRP concentrations were significantly positively associated with residence ≤100 m of a roadway, >100 m and ≤200 m of a roadway and increased traffic density for individuals using insulin. For individuals using oral hypoglycemic medications (OHAs), CRP was significantly negatively associated with residence >100 m – ≤200 m of a roadway and multiple roadway exposure in an interaction model. Among people with diabetes, individuals on insulin appear to be most vulnerable to the effects of traffic exposure. Disease severity among insulin users may promote the pro-inflammatory response to traffic exposure, though diabetes medications may also modify the response. Possible anti-inflammatory effects of OHAs with traffic exposure merit further evaluation.
Показать больше [+] Меньше [-]Effect of pyrene on denitrification activity and abundance and composition of denitrifying community in an agricultural soil Полный текст
2011
Guo, Guang-Xia | Deng, Huan | Qiao, Min | Mu, Yu-Jing | Zhu, Yong-Guan
Toxicity of pyrene on the denitrifiers was studied by spiking an agricultural soil with pyrene to a series of concentrations (0–500mgkg⁻¹) followed by dose–response and dynamic incubation experiments. Results showed a positive correlation between potential denitrification activity and copy numbers of denitrifying functional genes (nirK, nirS and nosZ), and were both negatively correlated with pyrene concentrations. Based on the comparison of EC₅₀ values, denitrifiers harboring nirK, nirS or nosZ gene were more sensitive than denitrification activity, and denitrifiers harboring nirS gene were more sensitive than that harboring nirK or nosZ genes. Seven days after spiking with EC₅₀ concentration of pyrene, denitrifiers diversity decreased and community composition changed in comparison with the control. Phylogenetic analyses of three genes showed that the addition of pyrene increased the proportion of Bradyrhizobiaceae, Rhodospirillales, Burkholderiales and Pseudomonadales. Some species belonging to these groups were reported to be able to degrade PAHs.
Показать больше [+] Меньше [-]Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds Полный текст
2011
Roscales, Jose L. | González-Solís, Jacob | Calabuig, Pascual | Jiménez, Begoña
PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels.
Показать больше [+] Меньше [-]How seasonality affects the flow of estrogens and their conjugates in one of Japan’s most populous catchments Полный текст
2011
Kumar, Vimal | Nakada, Norihide | Yamashita, Naoyuki | Johnson, Andrew C. | Tanaka, Hiroaki
A detailed study of the free and conjugated estrogen load discharged by the eight major sewage treatment plants into the Yodo River basin, Japan was carried out. Sampling campaigns were focused on the winter and autumn seasons from 2005 to 2008 and the free estrogens estrone(E1), 17β-estradiol(E2), estriol(E3), 17α-ethynylestradiol(EE2) as well as their conjugated (sulfate and glucuronide) forms. For both sewage effluent and river water E2 and E1 concentrations were greatest during the winter period (December–March). This coincides with the period of lowest rainfall and lowest temperatures in Japan. E1 was the dominant estrogenic component in effluent (means of 10–50 ng/L) followed by E2 (means of 0.5–3 ng/L). The estrogen sulfate conjugates were found intermittently in the 0.5–1.7 ng/L concentration range in the sewage effluents. The greatest estrogen exposure was found to be in the Katsura River tributary which exceeded 1 ng/L E2-equivalents during the winter period.
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