EXTRAÇÃO DE POLUENTES ORGANOCLORADOS PERSISTENTES EM FRAGMENTOS REMANESCENTES DA MATA ATLÂNTICA, RJ: COMPARAÇÃO DE MÉTODOS

• Ano de defesa: 2007
• Autor(a) principal: Quinete, Natalia Soares
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Programa de Pós-graduação em Química; Química
• Palavras-chave em Português: Poluentes Orgânicos Persistentes, POPs; organoclorados; Solos; Material de referência certificado, Soxhlet; Ultrasom; Extração assistida por radiação microondas, GC/ECD; Validação.; Cromatografia gasosa; Compostos organoclorados - Análise química; Poluentes orgânicos persistentes; Análise química de poluentes; Persistent Organic Pollutants, POPs; Organochlorine; Soils; Certified reference material, Soxhlet; Ultrasound; Microwave assisted extraction, GC/ECD; Validation.; CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA::QUIMICA ANALITICA
• Link de acesso: https://app.uff.br/riuff/handle/1/20895

Persistent Organic Pollutants (POPs) are toxic substances of natural and anthropic origin that are ubiquitous pollutants in all environmental compartiments (soils, waters, air and biota). POPs have long half-lives in soils, sediments, air or biota and are hydrophobic and lipophilic. These characteristics confer persistence on the chemicals in biota, which accumulate a nd magnify in foodchains. POPs are normally stable and have the propensity to form a gas under appropriate environmental temperatures. Hence, they may volatilise from soil and contamined areas into the atmosphere. Because of their resistence to breakdown reactions in air, they can travel long distances (are subject to long-range atmospheric transport) before being re-deposited. Therefore, could acummulate in an area far removed from where they use or emmited. The Brazilian Environmental Legislation is still incipient regarding monitoring measures of the contamination and soil management. In this way, the main aim of this work was to perform a preliminary study to investigate the presence of the persistent organochlorine pollutants a and ß - HCH, lindane (?- HCH), alaclor, heptaclor, metolaclor, aldrin, endrin, dieldrin, a and ß endosulfan, DDT and isomers, in soils of remaining fragments of Mata Atlântica in the National Park of Serra dos Órgãos and in the region of Córrego Sujo catchment basins, tributary of Rio Preto. It was performed the extracion of POPs from soils using Soxhlet aparatus, ultrasound and microwave radiation energy, following by a cleanup step (C18 and/or Florisil) to eliminate matrix interferences, and further analysis by gas chromatography equipped with electon-capture detection (ECD) for identification and quantification of the POPs. The developed method for the determination of persistent organochlorine pollutants in soils was based in US-EPA recommended procedures and validated according to INMETRO instructions. It was obtained the detection and quantification limits for the instrument and method for the different soils matrix and extraction methodologies. Recoveries results obtained from spiked samples employing soxhlet, ultrasound and microowave assisted extraction methods showed values between 70 and 130 %, considered acceptable for trace analysis in environmental samples. It could be observed for some of the analyte recoveries values higher than 130 %, which can be related to matrix contribution, due to high organic carbon contents (8- 17 %). It was also performed a recovery study in certified reference material (ERM®- CC007) that showed good results. It was verified higher recoveries results when the microwave assisted extraction technique was used. In order to confirm the presence of analytes of interest in the analysed samples the exchange of estacionary phase was carried out. The obtained results showed low concentration of organochlorine compounds in the soils sampled in the studied areas. It could be concluded that this area is not considered of environmental concern.