Avaliação da contaminação das areias de praia do litoral do Espírito Santo por elementos-traço

• Autor(a) principal: Sousa, Rafael Mantovaneli
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/1648
• topic: Beach sand; Trace elements; Multivariate Optimization; Areia - contaminação; Elementos traços; ICP OES; Otimização multivariada; F AAS; Contaminação química; Areia de praia; Química; Contaminação (Tecnologia); 54

The state of Espírito Santo has a big touristic potential in its coast, thanks to the natural beauty in its beaches. Which are widely used for recreation. Due to the use and the occupation of the coastal region, this environment is subject to chemical and biological contamination of the sand, bringing risks to population that uses this space as recreational area, and to environment, which may harm the local biota. This present study aims to quantify Co, Cr, Ni, Pb, V, Zn, Fe and Mn in beach sand, verifying alterations in the concentration of these trace elements due to seasonal variations. Four sample campaigns have been carried out in four beaches in the metropolitan region of Espírito Santo, where two campaigns were in dry season and two in rainy season. For each season samples were collected before and after the cold front. Samples were collected from the kerb crest and from the beach face. In each sampling, topographic surveys were carried out to verify the changes in beach profiles during the campaign. A study of size distribution in beach sand samples was also carried out. Sand samples were digested with microwave oven, using 12,0 mL of a nitric-fluoride acid mixture (3:1), with a digestion program adapted to the method US EPA 3052 (1996). Co, Cr, Cu, Ni, Pb, V e Zn were determined by ICP OES and Fe and Mn by F AAS. Determination method accuracy was analyzed through certified standard material analysis (NIST 2702) and recuperation study (72-123%). The found quantification limits, in mg kg-1, were: 0,55 for Co, 2,45 for Cr, 0,36 for Cu, 2,08 for Ni, 0,85 for Pb, 3,26 for V, 0,39 for Zn, 0,57 for Fe and 0,23 for Mn. Analytes concentration range in mµ were: <LQ – 34,85 for Co, <LQ – 26,99 for Cr, <LQ – 34,36 for Cu, <LQ – 44,75 for Ni, <LQ – 31,92 for Pb, <LQ – 92,03 for V, <LQ – 84,51 for Zn, <LQ – 1768 for Fe and <LQ – 4428 for Mn. Quantification results of trace elements in beach sand indicates that majority of analytes are present in the sand, some of them in high concentrations. Pearson correlation studies were carried out to evaluate the profile and distribution of trace elements throughout the sampling campaigns with topographic surveys of the collection season. Was observed that, for some analytes, climate and seasonal changes influences in its concentrations, increasing or decreasing, indicating that sediment transportation relates to these elements distribution. Comparing our results with other works in literature, it was observed that the Espírito Santo coast beaches have higher concentrations of most analytes, which could be indicative of contamination.