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331.
Abstract

Glyphosate is the main herbicide currently used in the world due to wide applicability and efficiency in controlling weeds in many crops. However, its overuse may lead to undesirable impacts on the environment and to human health in the long run. This present study aimed to optimize and validate solid phase extraction (SPE) using an anionic resin for the simultaneous and direct determination of glyphosate and aminomethylphosphonic acid (AMPA) in water samples using high-performance liquid chromatography combined with inductively coupled plasma with triple quadrupole mass spectrometer (HPLC-ICP-MS/MS). The results showed that recovery percentage and relative standard deviation were 103.9?±?7.9 and 99.40?±?9.9% for glyphosate and AMPA, respectively. The validation certified that the method was precise, accurate, linear, and selective, with a limit of quantification of 1.09 and 0.29?μg L?1 for glyphosate and AMPA, respectively. The optimized methodology reached the concentration factor of 250 times and was successfully applied to analyze water samples from hydroponic cultivation of the eucalyptus seedlings. The results showed that the exudation process occurs at glyphosate doses starting from 2?L ha?1.  相似文献   
332.
Few studies have attempted to study the environmental Kuznets curve (EKC) hypothesis at the individual sector level using more than one sector at once. This paper investigates the existence of the EKC hypothesis in the Iberian countries (Portugal and Spain) using thirteen economic activity sectors for each, analyzing each individual sector’s cointegration and causality relationships considering carbon dioxide (CO2) emissions, sector gross value added and energy consumption. The findings of this paper using the autoregressive distributed lag (ARDL) approach only validate cointegration in six Portuguese sectors and in five of the Spanish sectors. Results confirm both short- and long-run bi-directional and unidirectional causality between economic growth, energy consumption and CO2 emissions, using the error correction model (ECM) and Toda and Yamamoto’s causality approaches. Moreover, results for Portuguese and Spanish sectors indicate an inverted U-shaped relationship only for one sector each. In some sectors there was evidence of a U-shaped relationship and in others the EKC hypothesis could be verified but no statistical significance was obtained. The study has significant contributions for sector policy, including implications to curtail energy pollutants by implementing environmental friendly regulations to sustain economic development at the sector level in the Iberian market. It also allows inferences to be made about the existence of different behaviors in comparative terms for the same economic activity sectors of the individual countries.  相似文献   
333.

An increasing number and amount of pharmaceuticals for human and veterinary use currently reach the aquatic environment, and the determination of their effects on aquatic organisms becomes of major importance. The 96-h fish lethal test is one of the conventional assays required for environmental hazardous assessment, but it is extremely time-consuming and costly, and it raises ethical concerns. In a broad study, we compared the ability of cell-based assays to detect, in absolute terms, lethal toxicity in fish due to pharmaceuticals in order to select sensitive cell lines to be posteriorly used as an alternative to fish testing. This study also explored the sensitivity of the rat cardiomyoblast H9c2(2-1) cell line and the suitability of the sulforhodamine B colorimetric assay regarding 15 pharmaceuticals belonging to 9 different therapeutic classes. The relation between in vivo and in vitro data was expressed as LC50,96h/EC50 ratios, and 66% of concordant data were attained. Accordingly, it was possible to conclude that cell-based assays could be considered a suitable alternative to fish lethal testing for pharmaceuticals, which, after validation, may dramatically reduce the number of fish required for environmental hazardous assessment. Several cell lines were selected as promising alternatives, but H9c2(2-1), HepG2, PLHC-1, and RTG-2 could be considered suitable starting cell types for further studies, as relevant results were obtained with low exposure times.

  相似文献   
334.
Environmental Science and Pollution Research - The collapse of the Fundão dam in Mariana, MG, in 2015 resulted in the overflow of more than 50 million m3 of mud containing mine tailings,...  相似文献   
335.
The fuel matrix used in Brazil is unique around the world. The intensive use of hydrated ethanol, gasohol (gasoline with 25% v/v of ethanol), compressed natural gas (CNG), and biodiesel leads to a peculiar composition of the urban atmosphere. From 1998 to 2002 an increase in formaldehyde levels was observed and since then, a reduction. This work presents a monitoring campaign that was executed from March 2004 to February 2009 by sampling at early morning on every sunny Wednesday for a total of 183 samples. The results indicate a strong reduction in formaldehyde levels from 2004 (average of 135.8 μg m?3 with SD 28.4 μg m?3) to 2009 (average of 49.3 μg m?3 with SD 27.4 μg m?3). The levels of acetaldehyde showed a slight reduction from 2004 (average of 34.9 μg m?3 with SD 8.0 μg m?3) to 2009 (average of 26.8 μg m?3 with SD 11.5 μg m?3). Comparing the results with the concurrent evolution of the fleet and of fuel composition indicates that the observed formaldehyde levels could be associated with the increase in ethanol use and in CNG use by engines with improved technology over the first converted CNG engines. Modelling studies using the OZIPR trajectory model and the SAPRC chemical mechanism indicate that formaldehyde is the main ozone precursor in Rio de Janeiro and acetaldehyde is the forth one.  相似文献   
336.
Forest fires represent a serious threat to public security in Europe due to the large burned area. Moreover, smoke pollution due to forest fire events is an important public health issue for the communities directly affected, and particularly for the personnel involved in firefighting operations. Aiming to contribute to the scientific knowledge concerning firefighters exposure to forest fires smoke, data of individual exposure to carbon monoxide, nitrogen dioxide, volatile organic compounds, and particulate matter were obtained during experimental field fires for a group of 10 firefighters equipped with portable “in continuum” measuring devices. Measured values are very high exceeding the Occupational Exposure Standard limits, in particular for peak limit thresholds. These are the first measurements and analysis of firefighter's individual exposure to toxic gases and particles in fire smoke experiments in Europe. However, they already indicate that urgent measures to avoid these levels of exposure are needed.  相似文献   
337.
This article introduces a method for assessing health and safety management systems (MAHS) that has two innovative characteristics: (a) it brings together the three main auditing approaches to health and safety (HS) – the structural approach (which assesses the system prescribed), the operational approach (which assesses what is really happening on the shop-floor) and the performance approach (which assesses the results of performance indicators); (b) it emphasizes the resilience engineering perspective on HS, which takes into consideration four major principles (flexibility, learning, awareness, and top management commitment). Such principles underlie seven major assessment criteria, which in turn are divided into items (e.g. hazard identification from a resilience perspective is an item that belongs to the criteria of production processes). The items are sub-divided into statements, which are the requirements that should be assessed based on interviews, analysis of documents and direct observations. Within the 112 requirements proposed, 38 of them have clear links with at least one out of the four resilience engineering principles adopted. The remaining requirements are based on traditional assumptions underlying the so-called best practices of HS management. The results of the assessment for each item are expressed by a score on a scale of compliance with the established requirements, ranging from 0% to 100%. The specific score within that scale is obtained from tables used to assess applications for the Brazilian national quality award. The MAHS was tested in a case study that was carried out in a factory that manufactures automobile exhaust systems, located in Brazil.  相似文献   
338.
Setaria parviflora (Poir.) Kerguélen and Paspalum urvillei Steudel are grasses that grow naturally in a soil with high iron contents. This study aimed to characterize morphoanatomically and histochemically the iron phytotoxicity on leaves and evaluate the phytoextraction potential of these grasses. Saplings were cultivated in hydroponic solution with and without excess Fe-EDTA. Regarding measurements taken on leaves, reduction was observed among treatments of Fe-EDTA on height values of abaxial epidermis and bundle sheath in both species. As for iron histolocalization, stronger reaction was observed in leaves of S. parviflora, in comparison with P. urvillei. Anatomical damage, such as protoplast retraction, irregular xylem, changes in cell volume, and cell collapse, and visual symptoms, like leaf bronzing, chlorosis, and necrosis, were similar in both species when exposed to excess iron; however, P. urvillei showed more severe damage. This species accumulated more iron in shoots than S. parviflora and therefore is more favorable for use in phytoextraction. The root system of both species accumulated higher iron concentrations in relation to shoots.  相似文献   
339.
Mercury in the Mediterranean,part I: spatial and temporal trends   总被引:1,自引:0,他引:1  
The present paper provides an overview of mercury studies performed in the Mediterranean Sea region in the framework of several research projects funded by the European Commission and on-going national programmes carried out during the last 15 years. These studies investigated the temporal and spatial distribution of mercury species in air, in the water column and sediments, and the transport mechanisms connecting them. It was found that atmospheric concentrations of Hg compounds, particularly oxidised Hg species observed at five coastal sites in the Mediterranean Sea Basin, are significantly higher compared with those recorded at five coastal sites distributed across N Europe, most probably due to natural emissions. Hg levels in water are comparable to other oceans. Anthropogenic and natural point sources show locally limited enrichments, while natural diffusive sources influence Hg speciation over larger areas. Results and statistic comparison of mercury species concentrations within Mediterranean compartments will be presented and discussed.  相似文献   
340.
Climate compatible development (CCD) has emerged as a new concept that bridges climate change adaptation, mitigation and community-based development. Progress towards CCD requires multi-stakeholder, multi-sector working and the development of partnerships between actors who may not otherwise have worked together. This creates challenges and opportunities that require careful examination at project and institutional levels and necessitates the sharing of experiences between different settings. In this paper, we draw on the outcomes from a multi-stakeholder workshop held in Mozambique in 2012, the final in a series of activities in a regional project assessing emerging CCD partnerships across southern Africa. The workshop involved policymakers, researchers and representatives from NGOs and the private sector. We employ a content analysis of workshop notes and presentations to identify the progress and challenges in moving four case study countries (the Democratic Republic of the Congo, Mozambique, Zambia and Zimbabwe) towards CCD pathways, by exploring experiences from both project and policy levels. To advance institutional support for the development of successful CCD policies, practices and partnerships, we conclude that there is a need for: (a) institutional development at the national level to strengthen coordination and more clearly define roles and responsibilities across sectors, based on the identification of capacity and knowledge gaps; (b) partnership development, drawing on key strengths and competences of different stakeholders and emphasising the roles of the private sector and traditional authorities; (c) learning and knowledge-sharing through national and regional fora; and (d) development of mechanisms that permit more equitable and transparent distribution of costs and benefits. These factors can facilitate development of multi-stakeholder, multi-level partnerships that are grounded in community engagement from the outset, helping to translate CCD policy statements into on-the-ground action.  相似文献   
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