966 resultados para Ememrging contaminants


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The use of organic compounds has been a good option to reduce spending on fertilizers, and gain increased productivity in the cultivation of lettuce. However, given the wide variety of raw materials used in the preparation of organic compounds, studies are needed to evaluate its effects on the release of essential nutrients to plants and on the release of contaminants such as heavy metals. The aim of this study was to evaluate the mineral nutrition and heavy metal contamination of lettuce in soils treated with doses and types of compost. The experiment was conducted in a greenhouse in randomized blocks in factorial scheme 5x4, with five types of organic compounds and four nitrogen levels (0, 35, 70 and 140 kg ha(-1) of N), with four replications. In general, the doses of the compounds were not enough to provide the necessary quantity of nutrients to the lettuce, with the exception of nitrogen. There was no increase in levels of heavy metals in the soil above that allowed by Brazilian legislation. Furthermore, compounds based on manure plus grass, and commercial compound caused increases in Zn concentration in plants at levels above the recommended for consumed.

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The present work deals with the study on the evaluation of the human health risks caused by the leaching of hydrocarbon products from a gas station in Sumaré-SP. First, a geoenvironmental diagnosis had to be done, where information such as: history of the area, chemicals involved, geological characteristics, transport, chemical analysis, were used to make it. The geoenvironmental diagnosis was used in the software RBCA tier 2 which established the risks by all possible pathways. The results indicated that there are risks for groundwater ingestion for commercial (on site and off site) and residential receptors and 10 that there´s risk for inhalation of vapors in enclosed space for the commercial receptor on site. The evaluation also calculated the specific target levels that the area needs to show, in order not to harm human beings and the environment. That makes RBCA a great tool that can helps the remediation actions needed to be done so that the human being and the environment remain secure.

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The dating of sediments in lakes, estuaries and rivers through radionuclides, when applied in association with other analitic methods (heavy metals, organic contaminants, etc.) allows analyses of the anthropogenic interference in the environment along the years. A geochronology of a sediment core from Untersee in Lake Constance, one of the most important hydric resources of Europe, was established through the Pb-210 method and adopting the CRS parameter (Constant Rate of Supply). The Cs-137 was successfully used to give basis to the results, as its additional input occurred in Chernobyl’s accident can be used as a marker to the year 1986. Associating the dating with the cores depth, the average mass accumulation rate and the sedimentation rate for the site were assessed (0,14 g/cm²/year and 4 mm/year respectively).

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The issue of solid waste disposal and urban growth are conflictive, since the areas where old uncontrolled refuse disposal were away from the city today are incorporated to the urban area population. Thus, now population is closer to the degradation of contaminants coming from waste disposal, and, in some cases, these areas become housing subdivisions. This work aims to support the diagnosis of a former landfill in the municipality of Rio Claro (SP), using geophysical methods through resistivity anomalies. In order to develop the diagnostic, it was utilized water and soil analysis of a preliminary report and techniques of vertical electrical sounding and electrical profiling. The areas influenced by the garbage presented less resistivity than the one of the natural subsoil. Through the interpretation of results, the local potentiometric map was elaborated, as well as a map of calculated resistivity. The interpretation of these products indicated a disagreement between the groundwater flow and the current topography, leading to an identification of a preferential direction of the contamination plume in the NE-SW. These observations prove the applicability of geoelectrical methods in areas of former waste disposal with little information.

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This paper deals with a case study of assessing risk to human health, with the study area of an industrial site in the city of Paulinia (SP) contaminated by oil, which is disturbing situation that occurs in the state of Sao Paulo, which represents risks for human health, as toxic and carcinogenic potential of petroleum products. As an essential foundation for risk assessment, a Geo-environmental diagnosis of the region was made, posing as historical information of the area and accidents, regional geology and hydrogeology, characterization of contaminants and affected media, contaminant transport and data on potential receptors and pathways. Because of the detection of contaminants above the intervention values CETESB (2005) it was possible to proceeded to quantify risks to human health and the determination of maximum acceptable concentrations for no damage to health, using the methodology and software RBCA Tier 2 (ASTM , 1998) and Spreadsheet Risk Assessment recently published by CETESB. The results showed the risk to the health of industrial workers and regular employees of civil works (both on site) for ingestion of groundwater and inhalation of vapors indoors.

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Groundwater in the Rio Claro district is predominantly extracted from low productivity wells on the Itararé Aquifer, from depths greater than 150 m. These factors in conjunction with increasing demand for water supply have stimulated many industries to exploit the Rio Claro Aquifer, constituted by Cenozoic sediments of the Rio Claro Formation, where hydraulic properties are poorly known. For this reason, it is necessary to study the possible vulnerable to contamination punctual locations of the aquifer, in order to enable proper management of these groundwater reserves and to allow continuity of supply. Thus, this study aims to assess the vulnerability to groundwater on contamination Rio Claro Aquifer, punctually in Mandu mining site area, located in the District of Ajapi, Rio Claro - SP, the company which operates and sells industrial sand. The risk of groundwater contamination depends on the relationship between the hydrogeological characteristics of the aquifer layer (vulnerability to contamination) and the pollutant load. To evaluate the susceptibility to contamination it was applied the method GOD (FOSTER and HIRATA, 1987; FOSTER et. al., 2002) and, in addition, field and laboratory tests were performed to chacacterize the granulometry of the strata, hydraulic conductivity and some physical indices to make the evaluation more assertive and detailed. Punctual contamination vulnerability found in the aquifer Rio Claro, was moderate, which means that the aquifer is vulnerable to some contaminants, but when continuously discharged or leached. Thus, Mandu mining has a great role on preventing the emission of contaminants in the process of extraction and processing of sand... (Complete abstract click electronic access below)

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Aquatic ecosystems are suffering many impacts caused by human activities resulting from the activities occurring around them. With technological progress observed in recent years, this environment has received large amounts of chemicals from industries, agriculture and urban area that affect the aquatic biota. Among these sources of contamination, the oil industry has contributed to the pollution of aquatic environments with both effluents as produced water well as oil spills and their derivatives having toxicity to various organisms. With all the environmental issues has increased concern about water quality and has been used ecotoxicological tests with aquatic organisms to ecosystems to assess the toxicity of chemicals present in the water. In this context the microcrustacea Daphnia similis stands out as a freshwater organism very representative of the aquatic fauna of rivers and high sensitivity to environmental impacts. Thus, the present study aimed to evaluate the lethal toxicity of crude oil and produced water on this microcrustacea. The results showed that the microcrustacea presented high sensitivity to contaminants primarily crude oil. There was also the influence of environmental variables pH and temperature on the survival of organisms

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This work is proposed to evaluate the potential risk of an inert landfill in the city of Rio Claro (SP), and also suggest a source for the contamination. The study was proposed because it is known that there were legal technicalities greetings to guarantee the quality of groundwater. Given the requirements of the Environmental Company of São Paulo (CETESB) were installed monitoring wells in the area; sampled to groundwater and its contamination was found. In addition, we analyzed the main characteristics of the area, the arrangement and characteristics of the waste, the local geology and the hydrogeological system, so that I could find the source of contaminants, and predict the direction of dispersion even in groundwater. At the end of the work presents conclusions, recommendations and proposals for mitigating action

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Plumbism is considered the oldest occupational disease. Among the pathophysiological effects associated with lead (Pb) are cardiovascular disorders. Many diseases that develop later in life are determined during the early stages of life, under the influence of exposure and preferred diet of the mother. Still, one should consider that many environmental contaminants at levels not harmful can determine pathophysiological processes if physical or chemical stressors and/or pathological conditions are present. In this context, the intrauterine malnutrition may represent an additional risk factor in exposure to Pb during pregnancy and lactation. For these reasons, the objective of this study was to evaluate the cardiovascular risk of weaned rats that have suffered perinatal exposure to Pb and intrauterine malnutrition, alone or in combination. After mating, female rats were divided into control (ctrl, ad libitum), food restriction (RA, the same diet 50% of consumption in the control group during pregnancy), exposed to Pb (500 ppm Pb in drinking water during pregnancy and lactation) and association (As, received the last two procedures in combination). Cumulative concentration-effect curves (CECs) to CaCl2 and noradrenaline (NA) were obtained in rings with and without endothelium of the same thoracic aorta from male weaned rats (23-25 days old). Maternal weight, litter weight, weight and number of pups at birth, anogenital distance, arterial blood pressure (ABP) and weight of tissues (kidney, liver, aorta, left ventricle) were evaluated. Changes in vascular reactivity were assessed by the maximum response (MR) and 50% effective concentration (EC50). Data were presented as mean ± SEM. Statistical analysis was performed by multifactorial analysis of variance and Tukey's post test. Body weight of dams did not differ between the experimental groups, except on the...(Complete abstract click electronic access below)

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The increase in the oil price and the current trend of using renewable raw materials for the production of chemicals renew the interest in the production of biobutanol that, produced by fermentation of agricultural raw materials, can be used as a component of gasoline and diesel. With the commercialization of new fuels, environmental damages due to spills can occur. Among other techniques, the clean-up of these contaminated areas can be achieved with bioremediation, a technique based on the action of microorganisms, which has the advantage of turning hazardous contaminants into non toxic substances such as CO2, water and biomass. Thus, bearing in mind the use of biobutanol in the near future as a gasoline extender and due to the lack of knowledge of the effects of butanol on the biodegradation of gasoline, this work aimed to assess the aerobic biodegradation of butanol/gasoline blends and butanol/diesel (20% v/v), being the latter compared to the ethanol/gasoline blend and biodiesel/diesel (20% v/v), respectively. Two experimental techniques were employed, namely the respirometric method and the redox indicator 2,6-dichlorophenol indophenol (DCPIP) test. In the former, experiments simulating the contamination of natural environments were carried out in biometer flasks, used to measure the microbial CO2 production. The DCPIP test assessed the capability of four inocula to biodegrade the fuel blends. In butanol/gasoline experiments the addition of the alcohols to the gasoline resulted in positive synergic effects on the biodegradation of the fuels in soil and...(Complete abstract click electronic access below)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)