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The objective of the current study was to evaluate the concentration of aluminum (Al), iron (Fe) and manganese (Mn) on water and on the sediment of urban rivers (Carahá, Caveiras and Ponte Grande) in Lages, located on the mountain region of Santa Catarina, placed in a coverage area of the Guarani Aquifer. The water and sediment samples were collected between May and October of 2016 in three urban rivers, following an environmental disturbance gradient. For the extraction of the metals present on the sample, it was used the methods 3030 - Standard Methods of Water and Wastewater (2005) for the water samples and ISO 11,466 (1995) for the sediment samples. The quantification of metals was performed through a high-resolution spectrometer with atomic absorption, with a flame automation (acetylene-air or nitrous oxide-air). To evaluate the quantification, it was used a certified material (SRM 2709a - San Joaquin Soil - NIST). On the water samples were found concentrations of Mn above of class III, defined by the Resolution 357/05 of the Environment National Board- Brazil. The Pearson correlation matrix showed a positive correlation between the variables Al/Fe, Fe/Mn e Al/Mn on sediment and Fe/Mn on water. For the sediment, it was found high concentrations of Al, Fe, and Mn in some of the samples. By the results found, it is evinced an increase in the concentration of Al and Fe on the Carahá river sediment, and concentrations of Al, Fe, and Mn on the Ponte Grande river sediment, on the spots located at Lages - SC. [ABSTRACT FROM AUTHOR]

The work presents a study through electroanalytical procedures for the determination of metals in gasoline samples. The determination of metals in fuel is an issue of environmental relevance because it believes that these elements can be released into the atmosphere causing damage to the environment and health. Also when present outside the established acceptable limit, the reactivity of these elements may directly imply the quality of the fuels. Thus, the use of low cost and efficient techniques such as electroanalytic are shown as a viable option for this purpose. The access to the metals by voltammetric techniques was only possible after the acid digestion of the samples and two digestion procedures were evaluated (Digestor Block and Microwaves) in different acid purities. The comparison between the two digestion systems (open and closed) using the same experimental conditions showed that the digestion in the closed system presented better results, due to the lower risk of contamination of the sample. The evaluated procedure presented satisfactory results from an analytical and statistical point of view and, therefore, it was considered adequate for the analyzed matrix. [ABSTRACT FROM AUTHOR]

The cemeteries have been present in the culture for many centuries. However, knowledge of the potential that is reported to contaminate the environment is more recent. Substances generated in the decomposition of human bodies may be potentially toxic, depending on their composition, however, the scientific study of the variables present in the cemetery is difficult because of the symbolic load it presents to society. Through a bibliographical survey, we tried to describe the possible contaminants generated by the putrefaction of bodies in cemeteries and the association that these cause. It was concluded that the ions adsorption capacity by soil is an important characteristic given by the clay fraction and qualification the soil as apt to receive cemetery activities. [ABSTRACT FROM AUTHOR]