Publications by authors named "Sonnia Parra"

Analytical methods for the determination of microplastics in sediments typically involve matrix drying, sieving, grinding, and flotation as part of the sample treatment. However, the real need for these steps and analytical validation studies are scarce. This work proposes a method that avoids the drying, sieving, and flotation procedures by using a direct acid attack of HNO₃/HCl (3:1) on wet sediment samples, assisted by microwave digestion.

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The aim of this study was to assess the levels of heavy metal pollution in the clay/silt fraction (<63 μm fraction) of marine sediments from Quintero Bay, Chile. For this, sediment samples were collected from 14 sites from the bay and analyzed for major and minor element determination. The metal concentrations found suggest an anthropogenic origin related with Cu, Se, Mo, As, Sb and Pb.

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Metal contents in soil samples are commonly used to evaluate contamination levels. However, the distribution of metals is dependent on particle size. We investigated the distribution of metals in various particle size fractions of the soil from four sites of the Puchuncaví Valley (Central Chile).

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