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Health effects of daily airborne particle dose in children: Direct association between personal dose and respiratory health effects Texte intégral
2013
Buonanno, Giorgio | Marks, Guy B. | Morawska, L. (Lidia)
Air pollution is a widespread health problem associated with respiratory symptoms. Continuous exposure monitoring was performed to estimate alveolar and tracheobronchial dose, measured as deposited surface area, for 103 children and to evaluate the long-term effects of exposure to airborne particles through spirometry, skin prick tests and measurement of exhaled nitric oxide (eNO). The mean daily alveolar deposited surface area dose received by children was 1.35 × 103 mm2. The lowest and highest particle number concentrations were found during sleeping and eating time. A significant negative association was found between changes in pulmonary function tests and individual dose estimates. Significant differences were found for asthmatics, children with allergic rhinitis and sensitive to allergens compared to healthy subjects for eNO. Variation is a child's activity over time appeared to have a strong impact on respiratory outcomes, which indicates that personal monitoring is vital for assessing the expected health effects of exposure to particles.
Afficher plus [+] Moins [-]Modelling relationships between lichen bioindicators, air quality and climate on a national scale: Results from the UK OPAL air survey Texte intégral
2013
Seed, Lindsay | Wolseley, P. A. | Gosling, Laura | Davies, Linda | Power, Sally A.
Air pollution has many negative effects on the natural environment, from changes in plant growth patterns to loss of ecosystem function. This study uses citizen science to investigate national-scale patterns in the distribution and abundance of selected lichen species on tree trunks and branches, and to relate these to air pollution and climate. Volunteers collected data for nine lichen indicators on 19,334 deciduous trees. Submitted data provided information on species-level patterns, and were used to derive composite lichen indices. Multiple linear regression and ANCOVA were used to model the relationships between lichen response variables on Quercus spp. and pollution, climate and location. The study demonstrated significant relationships between patterns in indicator lichens and levels of N- and S-containing pollutants on trunks and twigs. The derived lichen indices show great potential as a tool to provide information on local, site-specific levels of air quality.
Afficher plus [+] Moins [-]Toxicity testing of dispersed oil requires adherence to standardized protocols to assess potential real world effects Texte intégral
2013
Coelho, Gina | Clark, James | Aurand, Don
Recently, several researchers have attempted to address Deepwater Horizon incident environmental fate and effects issues using laboratory testing and extrapolation procedures that are not fully reliable measures for environmental assessments. The 2013 Rico-Martínez et al. publication utilized laboratory testing approaches that severely limit our ability to reliably extrapolate such results to meaningful real-world assessments.The authors did not adopt key methodological elements of oil and dispersed oil toxicity standards. Further, they drew real-world conclusions from static exposure tests without reporting actual exposure concentrations. Without this information, it is not possible to compare their results to other research or real spill events that measured and reported exposure concentrations.The 1990s' Chemical Response to Oil Spills: Ecological Effects Research Forum program was established to standardize and conduct exposure characterization in oil and dispersed oil aquatic toxicity testing (Aurand and Coelho, 2005). This commentary raises awareness regarding the necessity of standardized test protocols.
Afficher plus [+] Moins [-]Dechlorane Plus flame retardant in terrestrial raptors from northern China Texte intégral
2013
Chen, Da | Wang, Yan | Yu, Lehuan | Luo, Xiaojun | Mai, Bixian | Li, Shaoshan
While a number of studies have addressed the environmental presence and behavior of the Dechlorane Plus (DP) flame retardant, there is still a dearth of information in terrestrial ecosystems. The present study revealed that median ∑DP (including anti- and syn-DP isomers) concentrations ranged from 10 to 810 ng/g lipid weight in muscle and liver tissues of six terrestrial raptor species collected in 2004–2006 from Beijing, China. Some concentrations rival the greatest DP burdens ever reported in global wildlife. Significant, positive correlations were observed between fanti (concentration ratio of anti-isomer to ∑DP) and ∑DP concentrations in the Eurasian sparrowhawk (Accipiter nisus) tissues. These results suggested that the DP burdens could be substantially driven by the accumulation of the anti-isomer in terrestrial birds. The tissue-specific accumulation of DP further suggested that factors (e.g., hepatic binding enzymes) other than lipid solubility could be important in determining tissue deposition of DP.
Afficher plus [+] Moins [-]Modelling mercury concentrations in prey fish: Derivation of a national-scale common indicator of dietary mercury exposure for piscivorous fish and wildlife Texte intégral
2013
Depew, David C. | Burgess, Neil M. | Campbell, Linda M.
The National Descriptive Model for Mercury in Fish (NDMMF) was applied to a Canada – wide dataset of fish mercury (Hg) concentrations to derive a common indicator of dietary methylmercury (MeHg) exposure (HgPREY) to piscivorous fish and wildlife. The NDMMF provided unbiased parameter estimates and strong spatial biases in prediction error were not apparent. Prediction error was comparatively higher when sample sizes were small and events with high Hg concentrations. Estimates of HgPREY from 1936 locations between 1990 and 2010 averaged 0.09 ± 0.07 μg g−1 (wet wt) and increased from west to east in a manner consistent with independent measures of MeHg exposure in piscivorous wildlife and conceptual models of aquatic ecosystem sensitivity to Hg methylation and bioaccumulation. The HgPREY dataset offers an approach to evaluate the risk of MeHg exposure to piscivorous fish and wildlife on a continental scale.
Afficher plus [+] Moins [-]Pb and Zn imaging and in situ speciation at the geogenic/biogenic interface in sentinel earthworms using electron microprobe and synchrotron micro-focus X-ray spectroscopy Texte intégral
2013
Morgan, A.J. | Kille, P. | Bennett, A. | O'Reilly, M. | Fisher, P. | Charnock, J.M.
Using synchrotron- and electron microscope-based X-ray microanalyses, the distribution and speciation of Zn and Pb were examined in situ in two earthworm species (Dendrodrilus rubidus and Lumbricus rubellus) living in heavily-polluted soils. Main findings: (i) Zn spectra in ingested soil and in tissues more closely resembled Zn3(PO4)2 than ZnS; (ii) Zn speciation in tissues gave a best fit for Zn to the inner shell of 4 oxygens at 1.94 Å (or nitrogens at 1.96 Å); (iii) the best fit for Pb in tissue was with a shell of oxygens at 2.18 Å and a shell of sulphurs at 2.67 Å; (iv) a component of the Zn and much of the Pb detectable in gut contents was co-distributed with S; (v) Zn and Pb display ‘soft’ acid affinities in soil, but ‘hard’ acid affinities in tissue. This is the first metal characterisation study conducted on an invertebrate quench-frozen in the field.
Afficher plus [+] Moins [-]Effects of water chemistry on the dissolution of ZnO nanoparticles and their toxicity to Escherichia coli Texte intégral
2013
Li, Mei | Lin, Daohui | Zhu, Lizhong
The dissolution of ZnO nanoparticles (nano-ZnO) plays an important role in the toxicity of nano-ZnO to the aquatic organisms. The effects of water chemistry such as pH, ionic components, and dissolved organic matter (DOM) on the dissolution of nano-ZnO and its toxicity to Escherichia coli (E. coli) were investigated in synthetic and natural water samples. The results showed that the toxicity of nano-ZnO to E. coli depended on not only free Zn2+ but also the coexisting cations which could reduce the toxicity of Zn2+. Increasing solution pH, HPO42−, and DOM reduced the concentration of free Zn2+ released from nano-ZnO, and thus lowered the toxicity of nano-ZnO. In addition, both Ca2+ and Mg2+ dramatically reduced the toxicity of Zn2+ to E. coli. These results highlight the importance of water chemistry on the toxicity evaluation of nano-ZnO in natural waters.
Afficher plus [+] Moins [-]Comparison of extended-spectrum-β-lactamase (ESBL) carrying Escherichia coli from sewage sludge and human urinary tract infection Texte intégral
2013
Zarfel, G. | Galler, H. | Feierl, G. | Haas, D. | Kittinger, C. | Leitner, E. | Grisold, A.J. | Mascher, F. | Posch, J. | Pertschy, B. | Marth, E. | Reinthaler, F.F.
For many years, extended-spectrum-beta-lactamase (ESBL) producing bacteria were a problem mainly located in medical facilities. Within the last decade however, ESBL-producing bacteria have started spreading into the community and the environment. In this study, ESBL-producing Escherichia coli from sewage sludge were collected, analysed and compared to ESBL-E. coli from human urinary tract infections (UTIs). The dominant ESBL-gene-family in both sample groups was blaCTX-M, which is the most prevalent ESBL-gene-family in human infection. Still, the distribution of ESBL genes and the frequency of additional antibiotic resistances differed in the two sample sets. Nevertheless, phenotyping did not divide isolates of the two sources into separate groups, suggesting similar strains in both sample sets. We speculate that an exchange is taking place between the ESBL E. coli populations in infected humans and sewage sludge, most likely by the entry of ESBL E. coli from UTIs into the sewage system.
Afficher plus [+] Moins [-]Passive sampling of perfluorinated chemicals in water: Flow rate effects on chemical uptake Texte intégral
2013
Kaserzon, Sarit L. | Vermeirssen, Etiënne L.M. | Hawker, Darryl W. | Kennedy, Karen | Bentley, Christie | Thompson, Jack | Booij, Kees | Mueller, Jochen F.
A recently developed modified polar organic chemical integrative sampler (POCIS) provides a means for monitoring perfluorinated chemicals (PFCs) in water. However, changes in external flow rates may alter POCIS sampling behaviour and consequently affect estimated water concentrations of analytes. In this work, uptake kinetics of selected PFCs, over 15 days, were investigated. A flow-through channel system was employed with spiked river water at flow rates between 0.02 and 0.34 m s−1. PFC sampling rates (Rs) (0.09–0.29 L d−1 depending on analyte and flow rate) increased from the lowest to highest flow rate employed for some PFCs (MW ≤ 464) but not for others (MW ≥ 500). Rs's for some of these smaller PFCs were increasingly less sensitive to flow rate as this increased within the range investigated. This device shows promise as a sampling tool to support monitoring efforts for PFCs in a range of flow rate conditions.
Afficher plus [+] Moins [-]Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia Texte intégral
2013
Wendling, Carolin | Huhn, Mareike | Nurina, Ayu | Bactiar, Ramadian | von Juterzenka, Karen | Lenz, Mark
Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia
2013
Wendling, Carolin | Huhn, Mareike | Nurina, Ayu | Bactiar, Ramadian | von Juterzenka, Karen | Lenz, Mark
It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (�13 and �18 units, both responses), hypoxia (0.5 mg/l, mortality only) and thermal stress (+7 �C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.
Afficher plus [+] Moins [-]Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia Texte intégral
2013
Wendling, Carolin Charlotte | Huhn, Mareike | Ayu, Nurina | Bachtiar, Ramadian | Juterzenka, Karen von | Lenz, Mark
It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (−13 and −18 units, both responses), hypoxia (0.5mg/l, mortality only) and thermal stress (+7°C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.
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