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271.
The aim of the present study is to determine the effect of blood lead on the health of industrial workers in United Arab Emirates (UAE). This is a cross-sectional pilot survey of blood lead levels (BLL) of 100 industrial workers (exposed) and 100 non-industrial workers (nonexposed), matched for age, sex and nationality selected from Al-Ain, Abu-Dhabi Emirate. Industrial workers had significantly higher mean of BLL (77.5+/-42.8 microg/dl and median 80.9 microg/dl) than non-industrial workers (19.8+/-12.3 microg/dl and median 11.0 microg/dl). In the present study, reported symptoms among industrial workers were strongly associated with BLL nausea/vomiting, muscular symptoms, dizziness, fatigue, irritability, memory disturbances, insomnia and allergic conjuctivitis, rhinitis and dermatitis. Furthermore, the present study revealed that industrial workers had higher prevalence of respiratory symptoms for phlegm, shortness of breath and diagnosed asthma. In conclusion, this study determined that occurrence of certain symptoms might be associated with lead exposure among industrial workers.  相似文献   
272.
Identifying and communicating uncertainty is core to effective environmental assessment (EA). This study evaluates the extent to which uncertainties are considered and addressed in Canadian EA practice. We reviewed the environmental protection plans, follow-up programs, and panel reports (where applicable) of 12 EAs between 1995 and 2012. The types of uncertainties and levels of disclosure varied greatly. When uncertainties were acknowledged, practitioners adopted five different approaches to address them. However, uncertainties were never discussed or addressed in depth. We found a lack of suitable terminology and consistency in how uncertainties are disclosed, reflecting the need for explicit guidance, and we present recommendations for improvement. Canadian Environmental Impact Statements are not as transparent with respect to uncertainties as they should be, and uncertainties in EA need to be better considered and communicated.  相似文献   
273.
Animal welfare involves societal and human values, ethical concerns and moral considerations since it incorporates the belief of what is right or what is wrong in animal treatment and care. This paper aims to ascertain whether the different dimensions of individual attitudes toward animal welfare in food choices may be characterized by general human values, as identified by Schwartz. For this purpose, an EU-wide survey was carried out, covering almost 2500 nationally representative individuals from five European countries. Compared with the previous literature this study shows a twofold novelty: (1) it develops a general framework to link individual enduring beliefs and attitudes toward animal welfare attributes in food choices; (2) the framework is analyzed within a broad-based cross-country study. Our empirical results prove that human values related to self-transcendence are strongly associated to overall animal welfare attitudes and especially to those explicitly related to food choices, while values related to the spheres of self-enhancement and conservatism are significantly associated to less sensitive attitudes to animal welfare. Moreover, our results appear to indicate that a determinant of animal welfarism in food choices is potentially associated to individual concerns regarding food safety issues.  相似文献   
274.
This study is part of our investigations about the release of persistent organic pollutants from melting Alpine glaciers and the relevance of the glaciers as secondary sources of legacy pollutants. Here, we studied the melt-related release of polychlorinated biphenyls (PCBs) in proglacial lakes and glacier streams of the catchment of the Silvretta glacier, located in the Swiss Alps. To explore a spatial and temporal distribution of chemicals in glacier melt, we combined two approaches: (1) analysing a sediment record as an archive of past remobilization and (2) passive water sampling to capture the current release of PCBs during melt period. In addition, we determined PCBs in a non-glacier-fed stream as a reference for the background pollutant level in the area. The PCBs in the sediment core from the Silvretta lake generally complied with trends of PCB emissions into the environment. Elevated concentrations during the most recent ten years, comparable in level with times of the highest atmospheric input, were attributed to accelerated melting of the glacier. This interpretation is supported by the detected PCB fractionation pattern towards heavier, less volatile congeners, and by increased activity concentrations of the radioactive tracer 137Cs in this part of the sediment core. In contrast, PCB concentrations were not elevated in the stream water, since no significant difference between pollutant concentrations in the glacier-fed and the non-glacier-fed streams was detected. In stream water, no current decrease of the PCBs with distance from the glacier was observed. Thus, according to our data, an influence of PCBs release due to accelerated glacier melt was only detected in the proglacial lake, but not in the other compartments of the Silvretta catchment.  相似文献   
275.
276.
The benthic ecosystem functioning is a rarely applied holistic approach that integrates the main chemical and biological features of the benthic domain with the key processes responsible for the flux of energy and C through the system. For the first time, such conceptual model, with an emphasis on the heterotrophic pathways, has been applied to the sediments at four stations within one of the most polluted coastal areas in Italy: the Mar Piccolo of Taranto. The functioning of the benthic ecosystem was different according to the investigated site. Nearby the military arsenal, i.e., the main source of organic contaminants and heavy metals, the system seemed inhibited at all the investigated structural and functional levels. Slow microbial processes of C reworking together with very limited densities of benthic fauna suggested a modest transfer of C both into a solid microbial loop and to the higher trophic levels. On the other hand, the ingression of marine water through the “Navigabile” channel seemed to stimulate the organic matter degradation and, consequently, the proliferation of meiofauna and macrofauna. In the innermost part of the basin, the system functioning, to some extent, is less impacted by contaminants and more influenced by mussel farms. The organic matter produced by these bivalves fueled faster C reworking by benthic prokaryotes and enhanced the proliferation of filter feeders.  相似文献   
277.
The increase use of pharmaceutical compounds in veterinary practice and human population results in the ubiquitous presence of these compounds in aquatic ecosystems. Because pharmaceuticals are highly bioactive, there is concern about their toxicological effects in aquatic organisms. Therefore, the aim of this study was to assess the effects of an effluent from a psychiatric hospital (containing a complex mixture of 25 pharmaceutical compounds from eleven therapeutic classes) on the freshwater clam Corbicula fluminea using a proteomic approach. The exposure of C. fluminea to this complex effluent containing anxiolytics, analgesics, lipid regulators, beta blockers, antidepressants, antiepileptics, antihistamines, antihypertensives, antiplatelets and antiarrhythmics induced protein changes after 1 day of exposure in clam gills and digestive gland more evident in the digestive gland. These changes included increase in the abundance of proteins associated with structural (actin and tubulin), cellular functions (calreticulin, proliferating cell nuclear antigen (PCNA), T complex protein 1 (TCP1)) and metabolism (aldehyde dehydrogenase (ALDH), alcohol dehydrogenase, 6 phosphogluconate dehydrogenase). Results from this study indicate that calreticulin, PCNA, ALDH and alcohol dehydrogenase in the digestive gland and T complex protein 1 (TCP1)) and 6 phosphogluconate dehydrogenase in the gills represent useful biomarkers for the ecotoxicological characterization of psychiatric hospital effluents in this species.  相似文献   
278.
Longer-term environmental studies are increasingly used to better understand contemporary ecosystems conditions and for forecasting their future trajectories. Here, we use radiometric measurements and the characterisation of sediment properties from six mountain and a lowland lake in Central Eastern Europe with the aim to assess temporal and spatial variability in sediment accumulation rates (SARs) in relation to three socio-economic regimes: traditional (1840–1948), socialist (1948–1989) and post-socialist (post-1990). We also set out to determine reference conditions for these lakes i.e. conditions before significant human impact. Our results show a trend of increasing SARs from basal sediments (pre 1840) towards the present at only two sites. This contrasts with findings from Western and Central European lakes where SARs have predominantly increased from 1850 towards the top of cores. We highlight the differential impacts of the traditional, socialist and post-socialist periods on the SARs at these lakes. Lowland and mid-elevations lakes (n = 2) were most markedly impacted by the socialist period of land use regime; lakes from the southern Carpathians (n = 2) were more impacted in the traditional period (transhumance pastoral activities), whereas those from the north (n = 3) in the socialist and post-socialist periods (summer pastoralism). Results from our study show a continuous anthropogenic impact during the entire period considered, even in remote mountain areas. This suggests that a temporal frame of 100–150 years is too short to meaningfully register the reference conditions of these lakes. Furthermore, a predominantly natural state may not have existed for centuries in this region.  相似文献   
279.
Demographic structure and its seasonal dynamics have been studied in colonies of narrow-skulled voles (Lasiopodomys gregalis Pall.) in Northern Kulunda. Three types of colonies have been distinguished: (I) true colonies (large, complex families), (II) simple families (nuclear or incomplete), and (III) all-male colonies. Changes in their sex, age, and functional composition (based on animal migration activity) during the breeding season have been analyzed.  相似文献   
280.
With globalization, virtual exchanges of natural resources embodied in traded commodities redistribute geographically land use and its environmental impacts. Benefits of national forest protection may be undermined at the global-scale by leakage through international trade. We studied land use displacement associated with national policies to protect forests in Bhutan. This case study provides a simple situation: a dominant forest cover almost unaffected by agricultural expansion, a rural economy dominated by the primary sector, centralized forest conservation policies, and a dominant trading partner. We assessed the net effects at the international level of the Bhutanese forest protection policies by accounting for trade in wood products with India. Our results show that these policies have been effective in maintaining a high forest cover, but have been accompanied by an increasing displacement of forest use to India. In 1996–2011, the difference between the total volume of wood imported from India and the total volume exported from Bhutan—i.e., the net displacement—corresponds to 27 % of the total volume consumed in Bhutan. In 2011, 68 % of the total forest area required to produce the wood consumed in Bhutan was located in India. The wood imported by Bhutan was likely originating from tree plantations in the northeastern Indian states. Since Bhutan has few tree plantations and very valuable natural forests, the net international-level ecological impacts of this land use displacement is arguably positive. Most of the wood imports of Bhutan were wood charcoal for its emerging chemical industries. This case of displacement reflects functional upgrading in the value-chain rather than an externalization of consumption-based environmental costs. Through its government policies, Bhutan has managed to support its economic development while protecting its forests and leapfrogging the negative impacts on forests generally associated with the early stages of modernization.  相似文献   
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