Contaminação radioativa: aspectos fundamentais associados à poluição nuclear

Since its discovery, radioactivity has brought numerous benefits to human societies. It has many applications in medicine, serving as a tool for non-invasive methods for diagnosis and therapies against diseases such as cancer. It also applies to technologies for energy in nuclear power plants with relatively low impacts on terms of perfect security. All applications, however, have risks, requiring maximum caution to drive processes and operations involving radioactive elements because, once released into the environment, they have extremely harmful effects on organisms affected. This paper presents fundamental concepts and principles of nuclear physics in order to understand the effects of radioactive elements released into the environment, culminating on the issue of radioactive contamination. Literature review allowed us to understand the radioactive contamination problem on living beings. Three major nuclear accidents have happened in the last thirty years, two of them in consecutive years. The nuclear accident at Chernobyl, Ukraine, in 1986, polluted large areas, condemning hundreds of thousands of people to live with consequences of the accident and effects of radiation, killing thousands of people throughout the years. In 1987, a major radiological accident occurred in Goiania (GO) when a source of radioactive cesium was violated, leading to the death of those who had direct or indirect contact with cesium. The most recent accident, in March, 2011, was located at the nuclear power plant in Fukushima Prefecture, Japan, after an earthquake and tsunami hit the region. There is no extensive and accurate knowledge about the consequences of the contamination entailed in that accident, although it is possible to verify signals on a global scale. An analysis of reports of contamination of large areas generated by nuclear plants with release of hazardous wastes suggests it is necessary to rethink the energy matrix of the various countries...

Mapeamento geoestatístico da permeabilidade superficial no entorno do Ribeirão Claro: e simulação da possibilidade de sua contaminação

The evaluation of soil permeability throughout the weathering profile is one of the most important features to be considered in environmental studies. This study, developed from field testing and analysis of data obtained by geostatistical methods, aims at mapping the permeability around the Ribeirão Claro river. The intent is to simulate an accident with toxic liquids where soil permeability is of fundamental importance. Another purpose of the research was to determine the minimum time that, in the event of an accident, a possible contaminant to reach the water table level and be routed to the nearest drain, in this case, the Ribeirao V Claro river constitutes fundamental information. The studied area of approximately 4 km² is located within the UNESP-Rio Claro campus, consisting of colluvial soil from Fm. Rio Claro superimposed on residual soil of Fm. Corumbataí. The method used to determine the permeability is the concentric cylinders performed on a sampling grid with 64 points containing spacing of 5 meters EW and 10 meters NS. In the places of permeability tests were collected samples for laboratory determination of the percentage of fines. From particle size analysis was performed and analysis statistical and geostatistical on this data. The histogram was based on the statistical studies, and the semivariograms were based on geostatistical estimation methods. Based on the comparison between the maps and the data obtained, it was determined that the percentage of fines in colluvial surface soil has little influence on permeability, which the proximity to the Ribeirao Claro river, the eastern portion, a factor that influences the distribution of permeability values

Simulação de contaminação de sedimentos e águas subterrâneas por gasolina e álcool: um estudo de monitoramento de variações das propriedades físico-químicas

Geophysics studies in areas impacted by petroleum derivatives describe abnormalities of both low and high electrical resistivity (the opposite of electrical conductivity), confirmed as contaminant phase by chemical analysis: this contradiction can be explained by degrading processes that naturally occur and create sub products that can change the environment conductivity. Monitoring the variation of the parameters mentioned serves as a comparative basis to the variation in geoelectrical parameters, which identified the correlation between the same contaminant parameters and the difference between their behavior studied apart, as well as its relations with the biodegradation process. The results are applied to the fuel distribution and storage sectors, leading to the diagnosis and monitoring of possible groundwater contamination scenarios, and the knowledge of the area exposure time to the contaminant, besides the better remediation alternative and impacts control. Among some conclusions, the most significant are the decrease in conductivity over time, so as the increase in Eh value in the gasoline contaminated tank, as well as the decrease in the pH value in the second tank with ethanol, which can be attributed to its degradation. Comparing the variations in both tanks, it is evident that Eh, pH and electrical conductivity do not behave temporally in a similar way, although some correlations between Eh and pH can be related.

Estudo de variações bioquímicas e genotoxicidade induzidas por mistura de contaminantes em tilápia (Oreochromis niloticus), como biomarcadores de contaminação ambiental

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

Efeito da aspersão de água sobre a contaminação microbiológica em esteiras transportadoras de cortes de frango

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Conhecimento e atitudes da área da saúde frente ao risco de contaminação por hepatites ao fazer as unhas

Pós-graduação em Saúde Coletiva - FMB

Avaliação preliminar da contaminação do aquífero Bauru em um município com vocação para avicultura

Pós-graduação em Engenharia Civil e Ambiental - FEB

Contaminação do lençol freático por hidrocarbonetos na região de Avaré - SP

Pós-graduação em Engenharia Civil e Ambiental - FEB

Índice de contaminação: novo parâmetro para análise de metais e de pesticidas no sangue materno e do cordão umbilical

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diagnóstico parasitológico de horticultures no monitoramento da contaminação parasitária em ambientes rurais

The objective of this study was to detect possible carriers of parasites and/or commensals between the horticulturists of Fair of the Producer from Upper Paranaiba, Minas Gerais. A total of 30 horticulturists were instructed to collect three stool samples on alternate days during the months of August and September 2007. Horticulturists were positive 40% for one or more parasite and / or dinner, and found: Giardia lamblia (3.5%), Entamoeba histolytica / E. dispar (7%), Entamoeba coli (13%), Endolimax nana (13%) and Ascaris lumbricoides (3.5%). Stool of gardeners is of importance in monitoring parasite sanitary conditions of vegetables sold in urban environments.

Efeito da β-amilase e α-amilase fúngica seguido de desramificação na formação e características estruturais de amido resistente tipo 3 de batata e araruta

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da contaminação por Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) na espermatogênese de Triatomíneos (Hemiptera: Reduviidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos bioquímicos de contaminação em girinos de Eupemphix nattereri expostos a solos contendo o agrotóxico fipronil e seus produtos de degradação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da influência da fermentação fúngica em estado sólido na obtenção de compostos fenólicos a partir de resíduos de café

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

Efeito da fermentação fúngica no teor de compostos fenólicos em casca de café robusta

Coffee husk is an abundant by-product generated by the coffee industry and it can be used for the production of-value-added phenolic compounds. Currently, this residue has no commercial use due to the presence of anti-nutritional compounds and it is returned to the soil or burned. The aim of this study was to evaluate the content of phenolic compounds in Robusta coffee husk, the adequacy of this residue as substrate for fermentation processes, as well as evaluating the influence of fungal solid state fermentation to obtain phenolic compounds from this residue. In the present study, the use of different solvents for the extraction of polyphenols was evaluated and the content was found to be in the range of 96.9-159.5 mg of galic acid (GA).g(-1) substrate, depending on the solvent used. The best solvent was acetone, therefore it was selected for extraction. Studies were carried out to evaluate the effect of solid-state fermentation in the release of phenolic compounds, using the filamentous fungi Penicillium purpurogenum. The total phenolic content increased from 159.5 up to 243.2 mg GA.g(-1) substrate as a result the solid-state fermentation.