Analysis of trace evidences in sediments and soils at points on the banks of the Piracicaba River and evaluation of its forensic potential

• Grant number: 21/01162-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2021
• End date: May 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Luiz Carlos Ruiz Pessenda
• Grantee: Dayana Rodrigues da Silva
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

This project aims to characterize and identify trace evidence (pollen and spores grains, diatoms and phytoliths) found at surface sediment/soil samples and to evaluate the use of these materials in the forensic context. The study will be conducted in the city of Piracicaba/SP, on the bank of the city's main river, where three points of collection of surface sediment/soil samples will be established for palynological, diatomological and phytolytic analysis, in addition to color characterization, pH analysis in KCl and granulometry of the sediment samples and soil classification. Furthermore, a simulated walk will be performed at these points and the remaining sediment/soil in the shoes used during it will also be sampled, in order to verify the possibility of correlating the concentration of the trace evidence retained in the shoes with the spectra found in the sediment/soil samples. Pollen samples will be treated using standard palynological preparation with acetolysis by acetic anhydride and sulfuric acid, while diatom and phytolith slides will be treated with H2O2 e HCl. The software Tilia and Tilia Graph will be used for plotting diagrams and calculating the concentrations of pollen and spores grains, diatoms and phytoliths in the samples. At the end of this study, it is estimated that it will be possible to obtain an overview of the diversity of these trace evidence in the different sediments/soils that occur on the banks of Piracicaba River and expand the bibliography on the Brazilian environmental reality. Moreover, this work will contribute to the testing and evaluation of protocols adapted for forensic palynology in Brazil, in order to assist in the consolidation of this tool as one to be routinely used by the Brazilian criminal expert.Keywords: Trace Evidence; Sediment; Soil; Protocols; Forensic Palynology; Piracicaba River. (AU).