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Microplastic litter composition of the Turkish territorial waters of the Mediterranean Sea, and its occurrence in the gastrointestinal tract of fish Полный текст
2017
Güven, Olgaç | Gökdağ, Kerem | Jovanović, Boris | Kıdeyş, Ahmet Erkan
Microplastic pollution of marine environment is receiving increased publicity over the last few years. The present survey is, according to our knowledge, the survey with the largest sample size analyzed, to date. In total, 1337 specimens of fish were examined for the presence of plastic microlitter representing 28 species and 14 families. In addition, samples of seawater and sediment were also analysed for the quantification of microplastic in the same region. Samples of water/sediment were collected from 18 locations along the Mediterranean coast of Turkey. 94% of all collected plastic microlitter from the sea was in the size range between 0.1 and 2.5 mm, while the occurrence of other sizes was rare. The quantity of microplastic particles in surface water samples ranged from 16 339 to 520 213 per km2. Fish were collected from 10 locations from which 8 were either shared with or situated in the proximity of water/sediment sampling locations. A total of 1822 microplastic particles were extracted from stomach and intestines of fish. Majority of ingested particles were represented by fibers (70%) and hard plastic (20.8%), while the share of other groups: nylon (2.7%), rubber (0.8%) and miscellaneous plastic (5.5%) were low. The blue color of plastic was the most dominant color. 34% of all examined fish had microplastic in the stomach. On average, fish which had microplastic contained 1.80 particle per stomach. 41% of all fish had microplastic in the intestines with an average of 1.81 particle per fish. 771 specimens contained microplastic in either stomach and/or intestines representing 58% of the total sample with an average of 2.36 particles per fish. Microplastic was found in all species/families that had sample size of at least 2 individuals. The number of particles present in either stomach or intestines ranged between 1 and 35. Ingested microparticles had an average diameter ±SD of 656 ± 803 μm, however particles as small as 9 μm were detected. The trophic level of fish species had no influence whatsoever on the amount of ingested microplastic. Pelagic fish ingested more microplastic than demersal species. In general, fish that ingested higher number of microplastic particles originated from the sites that also had a higher particle count in the seawater and sediment.
Показать больше [+] Меньше [-]Factors controlling spatial and temporal patterns of multiple pesticide compounds in groundwater (Hesbaye chalk aquifer, Belgium) Полный текст
2017
Hakoun, Vivien | Orban, Philippe | Dassargues, Alain | Brouyère, Serge
Factors governing spatial and temporal patterns of pesticide compounds (pesticides and metabolites) concentrations in chalk aquifers remain unclear due to complex flow processes and multiple sources. To uncover which factors govern pesticide compound concentrations in a chalk aquifer, we develop a methodology based on time series analyses, uni- and multivariate statistics accounting for concentrations below detection limits. The methodology is applied to long records (1996–2013) of a restricted compound (bentazone), three banned compounds (atrazine, diuron and simazine) and two metabolites (deethylatrazine (DEA) and 2,6–dichlorobenzamide (BAM)) sampled in the Hesbaye chalk aquifer in Belgium. In the confined area, all compounds had non-detects fractions >80%. By contrast, maximum concentrations exceeded EU's drinking-water standard (100 ng L−1) in the unconfined area. This contrast confirms that recent recharge and polluted water did not reach the confined area, yet. Multivariate analyses based on variables representative of the hydrogeological setting revealed higher diuron and simazine concentrations in the southeast of the unconfined area, where urban activities dominate land use and where the aquifer lacks protection from a less permeable layer of hardened chalk. At individual sites, positive correlations (up to τ=0.48 for bentazone) between pesticide compound concentrations and multi-annual groundwater level fluctuations confirm occurrences of remobilization. A downward temporal trend of atrazine concentrations likely reflects decreasing use of this compound over the last 28 years. However, the lack of a break in concentrations time series and maximum concentrations of atrazine, simazine, DEA and BAM exceeding EU's standard post-ban years provide evidence of persistence. Contrasting upward trends in bentazone concentrations show that a time lag is required for restriction measures to be efficient. These results shed light on factors governing pesticide compound concentrations in chalk aquifers. The developed methodology is not restricted to chalk aquifers, it could be transposed to study other pollutants with concentrations below detection limits.
Показать больше [+] Меньше [-]Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions Полный текст
2017
Ochoa-Hueso, Raúl | Munzi, Silvana | Alonso, Rocío | Arróniz-Crespo, María | Avila, Anna | Bermejo, Victoria | Bobbink, Roland | Branquinho, Cristina | Concostrina Zubiri, Laura | Cruz Mínguez, Cristina | Cruz de Carvalho, Ricardo | De Marco, Alessandra | Dias, Teresa | Elustondo, David | Elvira, Susana | Estébanez, Belén | Fusaro, Lina | Gerosa, Giacomo | Izquieta-Rojano, Sheila | Lo Cascio, Mauro | Marzuoli, Riccardo | Matos, Paula | Mereu, Simone | Merino, José | Morillas, Lourdes | Nunes, Alice | Paoletti, Elena | Paoli, Luca | Pinho, Pedro | Rogers, Isabel B. | Santos, Arthur | Sicard, Pierre | Stevens, Carly J. | Theobald, Mark R.
Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions Полный текст
2017
Ochoa-Hueso, Raúl | Munzi, Silvana | Alonso, Rocío | Arróniz-Crespo, María | Avila, Anna | Bermejo, Victoria | Bobbink, Roland | Branquinho, Cristina | Concostrina Zubiri, Laura | Cruz Mínguez, Cristina | Cruz de Carvalho, Ricardo | De Marco, Alessandra | Dias, Teresa | Elustondo, David | Elvira, Susana | Estébanez, Belén | Fusaro, Lina | Gerosa, Giacomo | Izquieta-Rojano, Sheila | Lo Cascio, Mauro | Marzuoli, Riccardo | Matos, Paula | Mereu, Simone | Merino, José | Morillas, Lourdes | Nunes, Alice | Paoletti, Elena | Paoli, Luca | Pinho, Pedro | Rogers, Isabel B. | Santos, Arthur | Sicard, Pierre | Stevens, Carly J. | Theobald, Mark R.
Mediterranean Basin ecosystems, their unique biodiversity, and the key services they provide are currently at risk due to air pollution and climate change, yet only a limited number of isolated and geographically-restricted studies have addressed this topic, often with contrasting results. Particularities of air pollution in this region include high O3 levels due to high air temperatures and solar radiation, the stability of air masses, and dominance of dry over wet nitrogen deposition. Moreover, the unique abiotic and biotic factors (e.g., climate, vegetation type, relevance of Saharan dust inputs) modulating the response of Mediterranean ecosystems at various spatiotemporal scales make it difficult to understand, and thus predict, the consequences of human activities that cause air pollution in the Mediterranean Basin. Therefore, there is an urgent need to implement coordinated research and experimental platforms along with wider environmental monitoring networks in the region. In particular, a robust deposition monitoring network in conjunction with modelling estimates is crucial, possibly including a set of common biomonitors (ideally cryptogams, an important component of the Mediterranean vegetation), to help refine pollutant deposition maps. Additionally, increased attention must be paid to functional diversity measures in future air pollution and climate change studies to establish the necessary link between biodiversity and the provision of ecosystem services in Mediterranean ecosystems. Through a coordinated effort, the Mediterranean scientific community can fill the above-mentioned gaps and reach a greater understanding of the mechanisms underlying the combined effects of air pollution and climate change in the Mediterranean Basin.
Показать больше [+] Меньше [-]Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions Полный текст
2017
Ochoa Hueso, Raúl | Munzi, Silvana | Alonso, Rocío | Arróniz-Crespo, María | Avila, Anna | Bermejo, Victoria | Bobbink, Roland | Branquinho, Cristina | Concostrina-Zubiri, Laura | Cruz, Cristina | Cruz de Carvalho, Ricardo | De Marco, Alessandra | Teresa, Dias | Elustondo, David | Elvira, Susana | Estebanez, Belén | Fusaro, Lina | Gerosa, Giacomo | Izquieta-Rojano, Sheila | Lo Cascio, Mauro | Marzuoli, Riccardo | Matos, Paula | Mereu, Simone | Merino, José | Morillas, Lourdes | Nunes, Alice | Paoletti, Elena | Paoli, Luca | Pinho, Pedro | Rogers, Isabel | Santos, Arthur | Sicard, Pierre | Stevens, Carly | Theobald, Mark | Biología
Los ecosistemas de la cuenca mediterránea, su biodiversidad única y los servicios clave que brindan están actualmente en riesgo debido a la contaminación del aire y el cambio climático; sin embargo, solo un número limitado de estudios aislados y geográficamente restringidos han abordado este tema, a menudo con resultados contrastantes. Las particularidades de la contaminación del aire en esta región incluyen altos niveles de O3 debido a las altas temperaturas del aire y la radiación solar, la estabilidad de las masas de aire y el predominio de la deposición seca de nitrógeno sobre la húmeda. Además, los factores abióticos y bióticos únicos (por ejemplo, el clima, el tipo de vegetación, la relevancia de los aportes de polvo del Sahara) que modulan la respuesta de los ecosistemas mediterráneos en diversas escalas espaciotemporales hacen que sea difícil comprender y, por tanto, predecir, las consecuencias de las actividades humanas que causan la contaminación del aire. Contaminación en la Cuenca Mediterránea. Por lo tanto, existe una necesidad urgente de implementar plataformas experimentales y de investigación coordinadas junto con redes más amplias de monitoreo ambiental en la región. En particular, es crucial contar con una red sólida de monitoreo de deposiciones junto con estimaciones de modelos, que posiblemente incluyan un conjunto de biomonitores comunes (idealmente criptógamas, un componente importante de la vegetación mediterránea), para ayudar a perfeccionar los mapas de deposición de contaminantes. Además, se debe prestar mayor atención a las medidas de diversidad funcional en futuros estudios sobre la contaminación del aire y el cambio climático para establecer el vínculo necesario entre la biodiversidad y la provisión de servicios ecosistémicos en los ecosistemas mediterráneos. A través de un esfuerzo coordinado, la comunidad científica mediterránea puede llenar los vacíos mencionados anteriormente y alcanzar una mayor comprensión de los mecanismos subyacentes a los efectos combinados de la contaminación del aire y el cambio climático en la cuenca mediterránea.
Показать больше [+] Меньше [-]Temporal trends of PM10 and its impact on mortality in Lombardy, Italy Полный текст
2017
Carugno, Michele | Consonni, Dario | Bertazzi, Pier Alberto | Biggeri, Annibale | Baccini, Michela
Exposure to particulate matter with diameter ≤10 μm (PM10) entails well documented adverse effects on human health. In the last decade, concentration of PM10 in Lombardy (10 million inhabitants), Italy, has been gradually decreasing. We evaluated how the mortality burden due to PM10 varied in that same period.We focused on 13 areas of the Region in 2003–2014: 11 cities with more than 50,000 inhabitants, 1 smaller alpine town and 1 agricultural province. For each area, we collected PM10 annual average concentrations and natural mortality data, and we used the posterior area-specific effects from a previous Bayesian meta-analysis to estimate the short-term impact of PM10 on mortality, in terms of deaths attributable (AD) to annual average exposures exceeding the WHO threshold of 20 μg/m3.PM10 annual average values showed a non-homogenous decreasing trend in the investigated time period in most of the areas. Overall, the population-weighted exposure levels decreased, except for a peak in 2011, but never met the WHO threshold. In 2003–2006, PM10 levels were responsible, on average, for 343.0 annual AD from natural causes that decreased to 253.5 in 2007–2010 and to 208.3 in 2011–2014. Overall we estimated that PM10 was responsible for about 1% of all natural deaths (min-max range: 0.86%–1.42%); the impact was heterogeneous among areas.By collecting routinely available data for the most populated areas in Lombardy, we returned a picture of air pollution and health trends in the last decade. Notwithstanding the observed reduction in PM10 between 2003 and 2014 and the resulting decline in the number of AD, the impact is still relevant. Hence, appropriate policies for emission reduction could have a further beneficial effect on population health. Studies based on routine data and local effect estimates are recommended to properly inform the policy-making process.
Показать больше [+] Меньше [-]Reducing N2O and NO emissions while sustaining crop productivity in a Chinese vegetable-cereal double cropping system Полный текст
2017
Yao, Zhisheng | Yan, Guangxuan | Zheng, Xunhua | Wang, Rui | Liu, Chunyan | Butterbach-Bahl, Klaus
High nitrogen (N) inputs in Chinese vegetable and cereal productions played key roles in increasing crop yields. However, emissions of the potent greenhouse gas nitrous oxide (N2O) and atmospheric pollutant nitric oxide (NO) increased too. For lowering the environmental costs of crop production, it is essential to optimize N strategies to maintain high crop productivity, while reducing the associated N losses. We performed a 2 year-round field study regarding the effect of different combinations of poultry manure and chemical N fertilizers on crop yields, N use efficiency (NUE) and N2O and NO fluxes from a Welsh onion-winter wheat system in the North China Plain. Annual N2O and NO emissions averaged 1.14–3.82 kg N ha⁻¹ yr⁻¹ (or 5.54–13.06 g N kg⁻¹ N uptake) and 0.57–1.87 kg N ha⁻¹ yr⁻¹ (or 2.78–6.38 g N kg⁻¹ N uptake) over all treatments, respectively. Both N2O and NO emissions increased linearly with increasing total N inputs, and the mean annual direct emission factors (EFd) were 0.39% for N2O and 0.19% for NO. Interestingly, the EFd for chemical N fertilizers (N2O: 0.42–0.48%; NO: 0.07–0.11%) was significantly lower than for manure N (N2O: 1.35%; NO: 0.76%). Besides, a negative power relationship between yield-scaled N2O, NO or N2O + NO emissions and NUE was observed, suggesting that improving NUE in crop production is crucial for increasing crop yields while decreasing nitrogenous gas release. Compared to the current farmers’ fertilization rate, alternative practices with reduced chemical N fertilizers increased NUE and decreased annual N2O + NO emissions substantially, while crop yields remained unaffected. As a result, annual yield-scaled N2O + NO emissions were reduced by > 20%. Our study shows that a reduction of current application rates of chemical N fertilizers by 30–50% does not affect crop productivity, while at the same time N2O and NO emissions would be reduced significantly.
Показать больше [+] Меньше [-]The role of melting alpine glaciers in mercury export and transport: An intensive sampling campaign in the Qugaqie Basin, inland Tibetan Plateau Полный текст
2017
Sun, Xuejun | Wang, Kang | Kang, Shichang | Guo, Junming | Zhang, Guoshuai | Huang, Jie | Cong, Zhiyuan | Sun, Shiwei | Zhang, Qianggong
Glaciers, particularly alpine glaciers, have been receding globally at an accelerated rate in recent decades. The glacial melt-induced release of pollutants (e.g., mercury) and its potential impact on the atmosphere and glacier-fed ecosystems has drawn increasing concerns. During 15th–20th August, 2011, an intensive sampling campaign was conducted in Qugaqie Basin (QB), a typical high mountain glacierized catchment in the inland Tibetan Plateau, to investigate the export and transport of mercury from glacier to runoff. The total mercury (THg) level in Zhadang (ZD) glacier ranged from <1 to 20.8 ng L−1, and was slightly higher than levels measured in glacier melt water and the glacier-fed river. Particulate Hg (PHg) was the predominant form of Hg in all sampled environmental matrices. Mercury concentration in Qugaqie River (QR) was characterized by a clear diurnal variation which is linked to glacier melt. The estimated annual Hg exports by ZD glacier, the upper river basin and the entire QB were 8.76, 7.3 and 157.85 g, respectively, with respective yields of 4.61, 0.99 and 2.74 μg m−2 yr−1. Unique landforms and significant gradients from the glacier terminus to QB estuary might promote weathering and erosion, thereby controlling the transport of total suspended particulates (TSP) and PHg. In comparison with other glacier-fed rivers, QB has a small Hg export yet remarkably high Hg yield, underlining the significant impact of melting alpine glaciers on regional Hg biogeochemical cycles. Such impacts are expected to be enhanced in high altitude regions under the changing climate.
Показать больше [+] Меньше [-]Trace element reference intervals in the blood of healthy green sea turtles to evaluate exposure of coastal populations Полный текст
2017
Villa, C.A. | Flint, M. | Bell, I. | Hof, C. | Limpus, C.J. | Gaus, C.
Exposure to essential and non-essential elements may be elevated for green sea turtles (Chelonia mydas) that forage close to shore. Biomonitoring of trace elements in turtle blood can identify temporal trends over repeated sampling events, but any interpretation of potential health risks due to an elevated exposure first requires a comparison against a baseline. This study aims to use clinical reference interval (RI) methods to produce exposure baseline limits for essential and non-essential elements (Na, Mg, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba, and Pb) using blood from healthy subadult turtles foraging in a remote and offshore part of the Great Barrier Reef. Subsequent blood biomonitoring of three additional coastal populations, which forage in areas dominated by agricultural, urban and military activities, showed clear habitat-specific differences in blood metal profiles relative to the those observed in the offshore population. Coastal turtles were most often found to have elevated concentrations of Co, Mo, Mn, Mg, Na, As, Sb, and Pb relative to the corresponding RIs. In particular, blood from turtles from the agricultural site had Co concentrations ranging from 160 to 840 μg/L (4–25 times above RI), which are within the order expected to elicit acute effects in many vertebrates. Additional clinical blood biochemistry and haematology results indicate signs of a systemic disease and the prevalence of an active inflammatory response in a high proportion (44%) of turtles from the agricultural site. Elevated Co, Sb, and Mn in the blood of these turtles significantly correlated with elevated markers of acute inflammation (total white cell counts) and liver dysfunction (alkaline phosphatase and total bilirubin). The results of this study support the notion that elevated trace element exposures may be adversely affecting the health of nearshore green sea turtles.
Показать больше [+] Меньше [-]The relationship between historical development and potentially toxic element concentrations in urban soils Полный текст
2017
McIlwaine, Rebekka | Doherty, Rory | Cox, Siobhan F. | Cave, Mark
Increasing urbanisation has a direct impact on soil quality, resulting in elevated concentrations of potentially toxic elements (PTEs) in soils. This research aims to assess if soil PTE concentrations can be used as an ‘urbanisation tracer’ by investigating geogenic and anthropogenic source contributions and controls, and considering PTE enrichment across historical urban development zones. The UK cities of Belfast and Sheffield are chosen as study areas, where available shallow and deep concentrations of PTEs in soil are compared to identify geogenic and anthropogenic contributions to PTEs. Cluster analysis and principal component analysis are used to elucidate the main controls over PTE concentrations. Pollution indices indicate that different periods of historical development are linked to enrichment of different PTEs. Urban subdomains are identified and background values calculated using various methodologies and compared to generic site assessment criteria. Exceedances for a number of the PTEs considered suggest a potential human health risk could be posed across subdomains of both Belfast and Sheffield. This research suggests that airborne diffuse contamination from often historical sources such as traffic, domestic combustion and industrial processes contribute greatly to soil contamination within urban environments. The relationship between historical development and differing PTEs is a novel finding, suggesting that PTEs have the potential for use as ‘urbanisation tracers’. The investigative methodology employed has potential applications for decision makers, urban planners, regulators and developers of urban areas.
Показать больше [+] Меньше [-]Fine and ultrafine atmospheric particulate matter at a multi-influenced urban site: Physicochemical characterization, mutagenicity and cytotoxicity Полный текст
2017
(Maurizio),
Particulate Matter (PM) air pollution is one of the major concerns for environment and health. Understanding the heterogeneity and complexity of fine and ultrafine PM is a fundamental issue notably for the assessment of PM toxicological effects. The aim of this study was to evaluate mutagenicity and cytotoxicity of a multi-influenced urban site PM, with or without the ultrafine fraction. For this purpose, PM2.5-0.3 (PM with aerodynamic diameter ranging from 0.3 to 2.5 μm) and PM2.5 were collected in Dunkerque, a French coastal industrial city and were extensively characterized for their physico-chemical properties, including inorganic and organic species. In order to identify the possible sources of atmospheric pollution, specific criteria like Carbon Preference Index (CPI) and PAH characteristic ratios were investigated. Mutagenicity assays using Ames test with TA98, TA102 and YG1041 Salmonella strains with or without S9 activation were performed on native PM sample and PM organic extracts and water-soluble fractions. BEAS-2B cell viability and cell proliferation were evaluated measuring lactate dehydrogenase release and mitochondrial dehydrogenase activity after exposure to PM and their extracts. Several contributing sources were identified in PM: soil resuspension, marine emissions including sea-salt or shipping, road traffic and industrial activities, mainly related to steelmaking or petro-chemistry. Mutagenicity of PM was evidenced, especially for PM2.5, including ultrafine fraction, in relation to PAHs content and possibly nitro-aromatics compounds. PM induced cytotoxic effects at relatively high doses, while alteration of proliferation with low PM doses could be related to underlying mechanisms such as genotoxicity.
Показать больше [+] Меньше [-]Uptake and translocation of imidacloprid, thiamethoxam and difenoconazole in rice plants Полный текст
2017
Ge, Jing | Cui, Kai | Yan, Huangqian | Li, Yong | Chai, Yangyang | Liu, Xianjin | Cheng, Jiangfeng | Yu, Xiangyang
Uptake and translocation of imidacloprid (IMI), thiamethoxam (THX) and difenoconazole (DFZ) in rice plants (Oryza sativa L.) were investigated with a soil-treated experiment at two application rates: field rate (FR) and 10*FR under laboratory conditions. The dissipation of the three compounds in soil followed the first-order kinetics and DFZ showed greater half-lives than IMI and THX. Detection of the three compounds in rice tissues indicated that rice plants could take up and accumulate these pesticides. The concentrations of IMI and THX detected in leaves (IMI, 10.0 and 410 mg/kg dw; THX, 23.0 and 265 mg/kg dw) were much greater than those in roots (IMI, 1.37 and 69.3 mg/kg dw; THX, 3.19 and 30.6 mg/kg dw), which differed from DFZ. The DFZ concentrations in roots (15.6 and 79.1 mg/kg dw) were much greater than those in leaves (0.23 and 3.4 mg/kg dw). The bioconcentration factor (BCF), representing the capability of rice to accumulate contaminants from soil into plant tissues, ranged from 1.9 to 224.3 for IMI, from 2.0 to 72.3 for THX, and from 0.4 to 3.2 for DFZ at different treated concentrations. Much higher BCFs were found for IMI and THX at 10*FR treatment than those at FR treatment, however, the BCFs of DFZ at both treatments were similar. The translocation factors (TFs), evaluating the capability of rice to translocate contaminants from the roots to the aboveground parts, ranged from 0.02 to 0.2 for stems and from 0.02 to 9.0 for leaves. The tested compounds were poorly translocated from roots to stems, with a TF below 1. However, IMI and THX were well translocated from roots to leaves. Clothianidin (CLO), the main metabolite of THX, was detected at the concentrations from 0.02 to 0.5 mg kg−1 in soil and from 0.07 to 7.0 mg kg−1 in plants. Concentrations of CLO in leaves were almost 14 times greater than those in roots at 10*FR treatment.
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