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Resultados 3491-3500 de 5,152
An ecological risk investigation of marine sediment from the northern Mediterranean coasts (Aegean Sea) using multiple methods of pollution determination Texto completo
2018
Tunca, Evren | Aydın, Mehmet | Şahin, ÜlküAlver
The aim of this study is an assessment of metal pollution levels in Aegean Sea sediment. Sediment samples collected from 7 different locations (Yeniköy, Edremit, Ayvalık, Dikili, Aliağa, Hekimadası, and Ildır) along the northern Mediterranean region of Turkey were investigated for 11 elements (Cu, Fe, Zn, V, Cd, Ni, As, Pb, Mn, Co, and Cr). Graphite furnace atomic absorption spectrophotometry (GFAAS) and flame atomic absorption spectrophotometry (FAAS) were used for elemental analysis. The findings were evaluated with sediment assessment methods by taking two different values as a reference and then investigating the adverse biological effects of elemental profiles on living organisms. Pb, Mn, As, Cd, and Cr concentrations were within a moderate to significant range in terms of contamination factor [Formula: see text]), albeit varying according to reference and location. The most problematic region and elements regarding the enrichment factor (EF) was Ayvalık and As, Ni, Cu, Pb, Co, and Cd. However, according to the EF, the anthropogenic effect was not at an alarming level. This was further supported by the results of the geoaccumulation index (Igeo). The findings of the modified degree of contamination (mC d) and the pollution load index (PLI) suggested that the accumulation was greatest in Ayvalık, and the least in Hekimadası and Ildır. The location with the highest elemental total toxic unit (ΣTU) was Edremit. The effect of the existing element profile on organisms was 21% in this location when the mean effect range–median quotient (m-ERM-q) was considered. As and Ni concentrations in all stations were found to be higher than threshold effect level (TEL) and Effect Range Low (ERL). Ni levels in Edremit exceeded the probable effect level (PEL) and Effect Range Median (ERM). Toxic unit (TU) values of these two elements in all stations ranged from 59.30 to 80.43%.
Mostrar más [+] Menos [-]Selection of tawny owl (Strix aluco) flight feather shaft for biomonitoring As, Cd and Pb pollution Texto completo
2018
Seoane, RitaGarcía | Río, ZulemaVarela | Ocaña, AlejoCarballeira | Escribano, JoséÁngel Fernández | Viñas, JesúsRamón Aboal
In this study, we determined the concentrations of As, Cd and Pb in the shaft of all primary flight feathers from ten tawny owl (Strix aluco) specimens, with the aim of selecting which shaft of the corresponding primary feather should be used in biomonitoring surveys to enable inter-individual comparisons of the levels of these metals. The birds had died between 2006 and 2013 and their bodies were stored in the various Wildlife Recovery Centres in Galicia (NW Spain). The analyses revealed a high degree of inter-shaft variability, mainly in the concentrations of As and Cd. However, it was possible to identify the most representative samples in each case: for As, the shaft of primary flight feather number 5 (S5) (which represented 11% of the total As excreted in all of the primary flight feathers); for Cd, the shaft of primary flight feather number 2 (S2) (11% of the total excreted); and for Pb, the shaft of primary flight feather number 8 (S8) (14% of the total excreted). However, the difficulties associated with the analytical determination of these pollutants in the shaft should be taken into account when this technique is applied in biomonitoring studies.
Mostrar más [+] Menos [-]Pedotransfer functions of potentially toxic elements in tropical soils cultivated with vegetable crops Texto completo
2018
Pedotransfer functions of potentially toxic elements in tropical soils cultivated with vegetable crops Texto completo
2018
The anthropogenic input of potentially toxic elements (PTEs) from industry, agrochemicals, etc., into the environment are of great concern. Models derived from pedotransfer functions can provide estimates of the levels of PTEs based on soil attributes. Based on the importance of these models in studies in contaminated areas, we assessed the concentrations of the reactive contents of Ba, Cu, Cr, Ni, Pb, and Zn in soils cultivated with vegetable crops in the state of São Paulo, Brazil. We also evaluated the influence of chemical and physical soil attributes on their reactivity and availability. The reactive contents of PTEs represent the fraction of PTEs easily sorbed at the adsorptions sites of organic matter, iron hydroxides, or clay. This fraction can supply information about the PTE content that is more or less readily released into the soil solution. The reactive and available fraction was extracted with 0.43 M HNO₃ and 0.01 M CaCl₂, respectively. The proportion of reactivity of metal pools decreased in the order of Ba>Zn > Cu > Pb > Ni > Cr. The empirical models were able to predict the relationship between the reactive fractions, the pseudototal content, and the soil attributes. The available concentrations of Cr, Cu, Ni, and Pb in the soils were lower than the limit of quantification, while 3% of the Ba content and 1% of the Zn content were available in the soil solution in relation to their pseudototal content, suggesting low mobility of these elements in the soil.
Mostrar más [+] Menos [-]Pedotransfer functions of potentially toxic elements in tropical soils cultivated with vegetable crops Texto completo
2018
Boim, Alexys G. F. | Rodrigues, Sónia M. | Dos Santos-Araújo, Sabrina N. | Pereira, Eduarda | Alleoni, Luís R. F.
The anthropogenic input of potentially toxic elements (PTEs) from industry, agrochemicals, etc., into the environment are of great concern. Models derived from pedotransfer functions can provide estimates of the levels of PTEs based on soil attributes. Based on the importance of these models in studies in contaminated areas, we assessed the concentrations of the reactive contents of Ba, Cu, Cr, Ni, Pb, and Zn in soils cultivated with vegetable crops in the state of São Paulo, Brazil. We also evaluated the influence of chemical and physical soil attributes on their reactivity and availability. The reactive contents of PTEs represent the fraction of PTEs easily sorbed at the adsorptions sites of organic matter, iron hydroxides, or clay. This fraction can supply information about the PTE content that is more or less readily released into the soil solution. The reactive and available fraction was extracted with 0.43 M HNO3 and 0.01 M CaCl2, respectively. The proportion of reactivity of metal pools decreased in the order of Ba>Zn > Cu > Pb > Ni > Cr. The empirical models were able to predict the relationship between the reactive fractions, the pseudototal content, and the soil attributes. The available concentrations of Cr, Cu, Ni, and Pb in the soils were lower than the limit of quantification, while 3% of the Ba content and 1% of the Zn content were available in the soil solution in relation to their pseudototal content, suggesting low mobility of these elements in the soil. | published
Mostrar más [+] Menos [-]Infections after photodynamic therapy in Condyloma acuminatum patients: incidence and management Texto completo
2018
Yu, Xin | Zheng, Heyi
Condyloma acuminatum (CA), or genital wart, is a sexually transmitted infection caused by human papillomaviruses. Increasing evidences demonstrated that photodynamic therapy (PDT) is effective in eliminating latent HPV infection, the major reason for CA recurrence. We observed an increasing number of infections after PDT in CA patients, which has not been reported before. This study aims to evaluate the incidence and management of infection in CA patients after PDT procedure. CA patients received PDT from January 2015 to February 2016 at the outpatient setting. Patients were randomly divided into two groups: the control group and fusidic acid group. Patients in the fusidic acid group used topical fusidic acid (2%) and recombinant human interferon after 5-aminolevulinic acid (ALA)-PDT procedure, while patients in the control group only used recombinant human interferon. Patients came to our department for follow-up evaluations at 4, 8, and 12 weeks after treatment for three times of PDT. Patients with ALA-PDT-associated infection were then randomly divided into two groups: the fusidic acid group and mupirocin group. During the 13-month study period, a total of 718 patients with 2154 times of PDT procedures were enrolled. The infection rate after PDT was 8.5% in the control group, while it was 1.1% in the prophylactic topical fusidic acid group. The cure rate of PDT-associated infection was 85.7% in the fusidic acid group and 86.7% in the mupirocin group. In conclusion, prophylactic topical antibiotic was useful for reduction of PDT-associated infection and optimal wound healing in CA patients.
Mostrar más [+] Menos [-]Mapping for the management of diffuse pollution risks related to agricultural plant protection practices: case of the Etang de l’Or catchment area in France Texto completo
2018
Mghirbi, Oussama | Bord, Jean-Paul | Le Grusse, Philippe | Mandart, Elisabeth | Fabre, Jacques
Faced with health, environmental, and socio-economic issues related to the heavy use of pesticides, diffuse phytosanitary pollution becomes a major concern shared by all the field actors. These actors, namely the farmers and territorial managers, have expressed the need to implement decision support tools for the territorial management of diffuse pollution resulting from the plant protection practices and their impacts. To meet these steadily increasing requests, a cartographic analysis approach was implemented based on GIS which allows the spatialization of the diffuse pollution impacts related to plant protection practices on the Etang de l’Or catchment area in the South of France. Risk mapping represents a support-decision tool that enables the different field actors to identify and locate vulnerable areas, so as to determine action plans and agri-environmental measures depending on the context of the natural environment. This work shows that mapping is helpful for managing risks related to the use of pesticides in agriculture by employing indicators of pressure (TFI) and risk on the applicator’s health (IRSA) and on the environment (IRTE). These indicators were designed to assess the impact of plant protection practices at various spatial scales (field, farm, etc.). The cartographic analysis of risks related to plant protection practices shows that diffuse pollution is unequally located in the North (known for its abundant garrigues and vineyards) and in the South of the Etang de l’Or catchment area (the Mauguio-Lunel agricultural plain known for its diversified cropping systems). This spatial inequity is essentially related to land use and agricultural production system. Indeed, the agricultural lands cover about 60% of the total catchment area. Consequently, this cartographic analysis helps the territorial actors with the implementation of strategies for managing risks of diffuse pollution related to pesticides use in agriculture, based on environmental and socio-economic issues and the characteristics of the natural environment.
Mostrar más [+] Menos [-]A multi-criteria sustainability assessment framework: development and application in comparing two food waste management options using a UK region as a case study Texto completo
2018
Iacovidou, Eleni | Voulvoulis, Nikolaos
Preventing food wastage is a key element of sustainable resource management. But as food waste is still generated at high volumes, priority is placed on its proper management as a resource, maximising sustainability benefits. This study, by integrating a multi-criteria decision analysis with a sustainability assessment approach, develops a screening and decision support framework for comparing the sustainability performance of food waste management options. A structured process for selecting criteria based on the consideration of environmental, economic and social aspects related to region-specific food waste system planning, policy and management has been developed. Two food waste management options, namely the use of food waste disposal units, which grind food waste at the household’s kitchen sink and discharge it to the sewer, and the anaerobic co-digestion of separately collected food waste with sewage sludge, were selected for comparison due to their potential to create synergies between local authorities, waste and water companies, with local circumstances determining which of the two options to adopt. A simplified process used for assessing and comparing the two food waste management options in the Anglian region in the UK, indicated that there are benefits in using the framework as a screening tool for identifying which option may be the most sustainable. To support decision-making, a detailed analysis that incorporates stakeholders’ perspectives is required. An additional use of the framework can be in providing recommendations for optimising food waste management options in a specific region, maximising their sustainability performance.
Mostrar más [+] Menos [-]Cytogenetic and genotoxic effects of 2-chlorophenol on Allium cepa L. root meristem cells Texto completo
2018
Küçük, Derya | Liman, Recep
2-Chlorophenol (2-CP), a class of chlorinated organic pollutants like other chlorophenols, is used as intermediate in the synthesis of the higher chlorinated congeners, certain dyes, preservatives, herbicides, fungicides, and plastics. In this study, cytotoxic and genotoxic effects of 2-CP were investigated on the root meristem cells of Allium cepa for its effects on root growth, mitotic index (MI), mitotic phases, chromosomal abnormalities (CAs), and DNA damage by using Allium anaphase-telophase and Comet assays. EC₅₀ of 2-CP value was determined as approximately 25 mg/L by Allium root growth inhibition test. Three concentrations of 2-CP (12.5, 25, and 50 mg/L), distilled water (negative control), and methyl methane sulfonate (MMS, 10 mg/L, positive control) were applied to onion stem cells under different exposure periods (24, 48, 72, and 96 h). All the applied doses of 2-CP slightly decreased MIs. 2-CP induced total CAs such as disturbed anaphase-telophase, chromosome laggards, stickiness, and bridges and also DNA damage at significant levels. These results demonstrate that 2-CP has genotoxic effects in A. cepa root meristematic cells.
Mostrar más [+] Menos [-]Effect of PM2.5 environmental pollution on rat lung Texto completo
2018
Yang, Biao | Guo, Jie | Xiao, Chunling
Particulate matter smaller than 2.5 μm (PM2.5) is a continuing challenge to pulmonary health. Here, we investigated the mechanisms involved in PM2.5 exposure-induced acute lung injury in rats. We analyzed biochemical and morphological changes following a 2-week “real-world” exposure. And then we found that PM2.5 exposure increased the concentrations of total protein, malondialdehyde, hydrogen peroxide, nitric oxide, and soluble elastin in bronchoalveolar lavage fluid, levels of cytokines in blood, and expression of MMP-9 in airways. Further, alveolar macrophage and neutrophil counts increased following PM2.5 exposure, and edema and lung lesions were observed. Our results suggest that PM2.5 exposure can induce oxidative stress and acute inflammatory responses, which can damage the micro-environment and decrease the repair ability of the lung, resulting in tissue damage.
Mostrar más [+] Menos [-]Phthalate exposure as a risk factor for hypertension Texto completo
2018
Lu, Xueling | Xu, Xijin | Lin, Yucong | Zhang, Yu | Huo, Xia
Phthalates are ubiquitous in environment. Hypertension is a major risk factor for cardiovascular diseases. Phthalate exposure is associated with hypertension in multiple studies. This review aims to summarize the scientific literature on associations between phthalate exposure and hypertension and discuss the mechanisms in the relationship. We identified and reviewed original articles published to March 2018, using PubMed and Web of Science to search the terms “phthalate(s),” “phthalic acid,” “blood pressure,” “high blood pressure,” “hypertension,” “prehypertension,” and “cardiovascular disease.” Findings were summarized based on the relevance to the themes, including presentation of main phthalates and their major metabolites as well as associations of phthalate exposure with blood pressure in epidemiological and experimental studies. We identified ten population-based investigations and five toxicological experiments. Epidemiological data underscored a possible correlation between phthalate exposure and hypertension in adults, whereas individual study in children stands on the opposite. Experimental studies mainly targeted the increasing effect of phthalates on blood pressure. This review suggested some underlying mechanisms of phthalate-associated hypertension. Considering the current evidence, phthalate might be risk factors of hypertension. However, the effect of phthalate exposure in early life on blood pressure in later life or adulthood is still unclear. Well-designed longitudinal and molecular mechanism studies are indispensable.
Mostrar más [+] Menos [-]How to assess the feeding activity in ecotoxicological laboratory tests using enchytraeids? Texto completo
2018
Bart, Sylvain | Roudine, Sacha | Amossé, Joël | Mougin, Christian | Péry, Alexandre R. R. | Pelosi, Céline
How to assess the feeding activity in ecotoxicological laboratory tests using enchytraeids? Texto completo
2018
Bart, Sylvain | Roudine, Sacha | Amossé, Joël | Mougin, Christian | Péry, Alexandre R. R. | Pelosi, Céline
The risk assessment of pesticides on soil fauna is an issue to protect agroecosystem sustainability. Enchytraeids are recognized as relevant soil bioindicators of chemical stress in agroecosystems. In laboratory, the reproduction test was found to be sensitive to reveal chemical impacts on enchytraeids. However, it does not allow to assess the impacts on ecological functions in which enchytraeids are involved. The objectives of this study were (i) to explore the feasibility of the bait-lamina test with enchytraeids under laboratory conditions and (ii) to compare its sensitivity with the Enchytraeid Reproduction Test. We exposed individuals of Enchytraeus albidus to two commercial formulations of fungicides widely used in Europe. The EC50 reproduction for the Swing® Gold (50 g L⁻¹ epoxiconazole and 133 g L⁻¹ dimoxystrobin) and the Cuprafor micro® (50% copper oxychloride) were respectively estimated at 1.66 ± 0.93 times the recommended dose and > 496 mg kg⁻¹ of copper. However, no impact was found on the feeding activity of enchytraeids. The bait-lamina test thus appeared less sensitive than the Enchytraeid Reproduction Test to the tested fungicides. Despite that, this test which is achievable under laboratory conditions and allows assessing indirect effects of pesticides is quick, cheap, and easy to perform. It would deserve to be used to explore longer-exposure effects through the repeated addition of bait-lamina sticks.
Mostrar más [+] Menos [-]How to assess the feeding activity in ecotoxicological laboratory tests using enchytraeids? Texto completo
2018
Bart, Sylvain | Roudine, Sacha | Amossé, Joël | Mougin, Christian | Pery, Alexandre R.R. | Pelosi, Céline | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Université Paris-Saclay | ANR-11-IDEX-0003,IPS,Idex Paris-Saclay(2011)
The risk assessment of pesticides on soil fauna is an issue to protect agroecosystem sustainability. Enchytraeids are recognized as relevant soil bioindicators of chemical stress in agroecosystems. In laboratory, the reproduction test was found to be sensitive to reveal chemical impacts on enchytraeids. However, it does not allow to assess the impacts on ecological functions in which enchytraeids are involved. The objectives of this study were (i) to explore the feasibility of the bait-lamina test with enchytraeids under laboratory conditions and (ii) to compare its sensitivity with the Enchytraeid Reproduction Test. We exposed individuals of Enchytraeus albidus to two commercial formulations of fungicides widely used in Europe. The EC50 reproduction for the Swing® Gold (50 g L−1 epoxiconazole and 133 g L−1 dimoxystrobin) and the Cuprafor micro® (50% copper oxychloride) were respectively estimated at 1.66 ± 0.93 times the recommended dose and > 496 mg kg−1 of copper. However, no impact was found on the feeding activity of enchytraeids. The bait-lamina test thus appeared less sensitive than the Enchytraeid Reproduction Test to the tested fungicides. Despite that, this test which is achievable under laboratory conditions and allows assessing indirect effects of pesticides is quick, cheap, and easy to perform. It would deserve to be used to explore longer-exposure effects through the repeated addition of bait-lamina sticks.
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