Initial Studies of the Potential of Forensic Palynology in Brazil

Resumo

Forensic Palynology has been shown to be effective in some cases around the world, and in countries that usually apply this technique, protocols have been developed in partnership with academic institutions. The premise that pollen and spores found in clothing of a suspect or victim may indicate crime geolocation has been tested in countries with more homogeneous vegetation and predominantly anemophilous pollination patterns. However, the feasibility of this technique in tropical settings is unknown due to the lack of landscape-clothing pollen transfer studies and the impact of predominantly entomophilous vegetation. This study evaluates the forensic potential of pollen, spores, diatoms and foraminifera retained in clothing and shoes as geolocation proxies after contact with a heterogenous landscape in southeastern Brazil. To simulate a crime route, three individuals walked along a trail starting at a beach, passing through restinga vegetation, reaching a mangrove forest. Residues were extracted from pants, shirts and shoes by washing and later treated with hydrofluoric acid and acetolysis for mineral and organic content removal, respectively. Diatoms were extracted with hydrogen peroxide and hydrochloric acid and foraminifera through filtration and flotation processes. The results show that these microtraces were found in the clothing and shoes worn during the simulation and indicated direct contact with landscapes such as beach and restinga vegetation, mangrove forest as well as fresh, brackish and seawater. This study suggests that the palynological technique can be added to Brazilian Forensic protocols used by scientific police forces as by other countries with similar environmental realities.