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81.
Waste from wastewater treatment plants (WWTP) for Helianthus annuus L. production may be a viable solution to obtain biodiesel. This study achieved two objectives: assess the agronomical viability of waste (wastewater and sludge) from the Alcázar de San Juan WWTP in central Spain for H. annuus L. production; use H. annuus L. seeds grown in this way to obtain biodiesel. Five study plots, each measuring 6 m × 6 m (36 m2), were set up on the agricultural land near the Alcázar de San Juan WWTP. Five fertilizer treatment types were considered: drinking water, as the control; treated wastewater; 10 t ha?1 of air-dried sewage sludge; 20 t ha?1 of air-dried sewage sludge; 0.6 t ha?1 of commercial inorganic fertilizer. Soil, irrigation water, sewage sludge, crop development and fatty acid composition in achenes oil were monitored. The 20 t ha–1 dose of sewage sludge proved effective to grow H. annuus L. with similar results to those grown with a commercial fertilizer. However, precautions should be taken when irrigating with wastewater because of high salinity and nutrient deficiency. Sunflower oil was composed mostly of linoleic and oleic acid. The remaining fatty acids were linolenic, estearic, nervonic, palmitoleic, and palmitic.  相似文献   
82.
Heavy metal contamination is a long-standing and very well-known public health problem, and its exposure can cause damage to several organs of human body, especially on the central nervous system of young children and teenagers. The aim of this article is to evaluate lead, cadmium, and manganese contamination in 125 children from 6 to 13 years old living in contaminated areas during the period from 2006 to 2009 (São Vicente, Cubatão Downtown, Bertioga and Cubatão Pilões/Água Fria). This estuary area is the most important example of environmental degradation by chemicals from industrial sources. This is a cross-sectional study through clinical examinations and dental enamel tests. All mothers from these children lived in the area since before the pregnancy. Lead, cadmium, and manganese levels (μg/g) were measured on dental enamel samples through graphite furnace atomic absorption spectrometry, searching for the occurrence of heavy metals. The mean lead concentrations were 139.48 μg/g in Cubatão Pilões/Água Fria, 170.45 μg/g in Cubatão Downtown, 213.52 μg/g in São Vicente, and 151.89 μg/g in Bertioga. The mean cadmium concentrations were 10.83 μg/g in Cubatão Pilões/Água Fria, 12.58 μg/g in Cubatão Downtown, 10.92 μg/g in São Vicente, and 14.57 μg/g in Bertioga. The mean manganese concentrations were 23.49 μg/g in Cubatão Pilões/Água Fria, 30.90 μg/g in Cubatão Downtown, 41.46 μg/g in São Vicente, and 42.00 μg/g in Bertioga. Dental surface enamel may be used as an efficient biomarker of past environmental exposure to lead, manganese, and cadmium which are associated to well-known sources of heavy metal contamination. The results suggest that the evaluated children were exposed to sources of lead, cadmium, and manganese since before their conceptions. Although Bertioga initially was chosen as a control area of this study, it was also was verified to have heavy metal contamination on examined children.  相似文献   
83.
The spatial variability of annual and seasonal precipitation in the conterminous land of Spain has been evaluated by using correlation decay distance analysis (CDD). The CDD analysis essentially explores how the correlation between neighbouring stations varies according to distance. We analysed CDD independently for the decades 1956–1965, 1966–1975, 1976–1985, 1986–1995, and 1996–2005 using only those stations with no missing values for each decade. To this end, 972, 1,174, 1,242, 773 and 695 complete series were used for each decade, respectively. In particular, for each station and decade, we calculated the threshold distance at which the common variance between target (i) and neighbour series is higher than 50 % (r 2  = 0.5) to evaluate whether current density of the climate data set captures the spatial variability of precipitation within the study area. Results indicate that, at an annual scale, neighbouring stations with 50 % of common variance are restricted on average to about 105 km, but this distance can vary from 28 to 251 km within the study area. The lowest variability is located to the SW and in winter, while the higher spatial variability is found to the north, in the Cantabrian area, and to the east, in the Mediterranean and Pyrenees, during summer. Our results suggest that current density of climate stations (those operating in 2005) is good enough to study precipitation variability at an annual scale for winter, spring and autumn, but not enough for summer.  相似文献   
84.
In this study, an analysis was performed on the concentrations of the trace elements Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in muscle of two carnivorous and one planktivorous fish species collected at Todos os Santos Bay (BTS). The accumulation order of the trace elements in Lutjanus analis was Al >Zn >Fe >Cr >Ba >Ni. In Cetengraulis edentulus, the order was Al >Fe >Zn >Cr >Ni >Mn >As. In the species Diapterus rhombeus, the order was Al >Fe >Zn >Cr >Ni >Mn >Cd. To determine the risk related to the consumption of fish, toxicity guidelines were used as standard references. It was observed that the species C. edentulus contained concentrations of As exceeding WHO limits, but these concentrations were acceptable according to the Agência Nacional de Vigilância Sanitária (ANVISA) guidelines. Cd levels were found only in D. rhombeus and in low concentrations according to the determinations of WHO and ANVISA. Pb levels were not detected in any of the three fish species. The analyzed elements did not differ statistically according to the species and feeding habits. The results point to possible risks of human contamination by As related to the consumption of the fish species C. edentulus from the BTS.  相似文献   
85.

Ingredients in home and personal care products, including UV filters and benzotriazoles, are high production volume chemicals extensively used in our daily life, despite several studies revealed their potential eco-toxicity and endocrine-disrupting capacity. Due to some features, such as high lipophilicity, low degradability, and persistence of many of these compounds, sediments can be considered a sink for them in the aquatic environment. In the present study, nine organic UV filters and three benzotriazoles were investigated for the first time in sediments from four urban rivers in Brazil. The contaminants were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results revealed that octocrylene (OC), etylhexyl-methoxycinnamate (EHMC), benzophenone-3 (oxybenzone, BP3), and benzotriazole (BZT) were the predominant compounds adsorbed on the sediments, with concentrations ranging from 5.6 to 322.2 ng g−1 dry weight. The results reported in this work constitute the first data on the accumulation of polar benzotriazoles and lipophilic organic UV filters in sediments from Brazil.

  相似文献   
86.
Differential white blood cell counting was performed on blood from the fish species Oreochromis niloticus and was used as an in situ indicator of the species’ exposure to contamination. Ten young fish were collected in an area influenced by the discharge of effluents and from a fish farm (control group). The fish were anesthetized and caudal puncture was used to collect the blood. Differential white blood cell counting was performed, as well as the counting of total leukocytes and thrombocytes (in 2000 cells). Physicochemical parameters of the water from both sites were analyzed. The water from the polluted area was found to have high conductivity and low levels of dissolved oxygen, factors that indicate poor environmental quality. Fish collected from the polluted site presented higher percentages of eosinophils and monocytes and fewer thrombocytes because of exposure to pollution and hypoxic conditions. The differential white blood cell count represents a suitable biomarker of environmental health and provides a tool for biomonitoring water quality.  相似文献   
87.
Performance evaluation is important in managing freight transport. The transport of certain products, especially those that are hazardous, can have significant financial and socio-environmental impacts. This article presents an application of the modal choice method (MCM) to establish an order of priority among the alternatives considered to carry a determined hazardous product. After a research of the literature on the concepts and development of the proposed method, we consulted experts about their experiences and knowledge, to determine a set of relevant attributes for the evaluation process. We then applied this method to the specific case of the Brazilian bio-ethanol industry, to demonstrate the potential of using the MCM as a tool to support make decisions. We can conclude that highway transport, though the most often used, is not the best compared to trains or pipelines (or combinations of any of the three) from a socio-environmental standpoint. Alternatives with longer pipeline segments are the most suitable to replace the current practice in environmental terms.  相似文献   
88.

Introduction  

Within the last decade, numerous studies have investigated the role of environmental history on tolerance to stress of many organisms. This study aims to assess if Manila clams Ruditapes philippinarum may react differently to cadmium exposure and trematode parasite infection (Himasthla elongata) depending on their origin and environmental history in Arcachon Bay (France).  相似文献   
89.
In this study, we seek to verify the contributions made by three international standards to efforts by eight companies to reduce their environmental impacts and move toward sustainable development. The standards considered in this article are the International Organization for Standardization's (ISO) 9001 (quality), ISO 14001 (environmental management systems), and the Occupational Health and Safety Assessment Series (OHSAS) 18001. The eight companies analyzed for this study are located in the state of Rio Grande do Sul in Brazil. As part of this work, the authors generated a proposed sustainable positioning matrix and placed each company within one of four quadrants—economic approach, environmental approach, social approach, and sustainability approach—derived from the context of the Triple Bottom Line (Elkington, 2004 ).  相似文献   
90.
We here examine species distribution models for a Neotropical anuran restricted to ombrophilous areas in the Brazilian Atlantic Forest hotspot. We extend the known occurrence for the treefrog Hypsiboas bischoffi (Anura: Hylidae) through GPS field surveys and use five modeling methods (BIOCLIM, DOMAIN, OM-GARP, SVM, and MAXENT) and selected bioclimatic and topographic variables to model the species distribution. Models were first trained using two calibration areas: the Brazilian Atlantic Forest (BAF) and the whole of South America (SA). All modeling methods showed good levels of predictive power and accuracy with mean AUC ranging from 0.77 (BIOCLIM/BAF) to 0.99 (MAXENT/SA). MAXENT and SVM were the most accurate presence-only methods among those tested here. All but the SVM models calibrated with SA predicted larger distribution areas when compared to models calibrated in BAF. OM-GARP dramatically overpredicted the species distribution for the model calibrated in SA, with a predicted area around 106 km2 larger than predicted by other SDMs. With increased calibration area (and environmental space), OM-GARP predictions followed changes in the environmental space associated with the increased calibration area, while MAXENT models were more consistent across calibration areas. MAXENT was the only method that retrieved consistent predictions across calibration areas, while allowing for some overprediction, a result that may be relevant for modeling the distribution of other spatially restricted organisms.  相似文献   
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