Avaliação toxicológica da fração aquosa resultado da fotodegradação do polietileno tereftalato (PET) em ambientes com simulação de luz solar
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Título principal
Avaliação toxicológica da fração aquosa resultado da fotodegradação do polietileno tereftalato (PET) em ambientes com simulação de luz solar [recurso eletrônico] / Bianca Vicente Costa Oscar ; orientador, William Gerson Matias ; coorientadora, Silvia Pedroso Melegari
Data de publicação
2023
Descrição física
92 p. : il.
Nota
Disponível somente em versão on-line.
Tese (doutorado) – Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Ambiental, Florianópolis, 2023.
Inclui referências.
Avaliação toxicológica da fração aquosa resultado da fotodegradação do polietileno tereftalato (PET) em ambientes com simulação de luz solar [recurso eletrônico] / Bianca Vicente Costa Oscar ; orientador, William Gerson Matias ; coorientadora, Silvia Pedroso Melegari
Data de publicação
2023
Descrição física
92 p. : il.
Nota
Disponível somente em versão on-line.
Tese (doutorado) – Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Ambiental, Florianópolis, 2023.
Inclui referências.
Abstract: Due to its versatility and functionality, plastic has become one of the most successful materials in modern society. These characteristics, combined with the low production cost, mean that the global production of plastic materials grows every year, and as a consequence of this unrestrained consumption we have the pollution generated by their inadequate disposal. The environmental problems of these materials are linked to the fact that most types of plastic are not biodegradable, taking centuries to completely degrade, accumulating in landfills or in the natural environment. After being dumped into the environment, plastic is susceptible to the action of abiotic and biotic factors that can cause degradation reactions of the material. Regardless of the method, the degradation of plastic materials results in their fragmentation into increasingly smaller pieces and the release of their chemical components. Most scientific research that considers the aging of plastic particles due to natural degradation processes aims to identify changes in plastic materials exposed to a specific degradation system, observing changes in the surface and structural characteristics of these residues after exposure. Nowadays, it is known that this prolonged exposure, in addition to generating data on the materials, also generates changes in the toxicological potential. And studies evaluating the toxicology of these aged particles are recent in the scientific world. Therefore, the present work aims to evaluate the toxic effects of the aqueous fraction resulting from the degradation of polyethylene terephthalate (PET) plastic fragments exposed for up to 24 hours to a degradation system that simulates solar radiation on the organisms D. magna and A. fischeri. Through atomic force microscopy and scanning electron microscopy analyses, deterioration of the surface of the plastic fragments was observed due to exposure to simulated sunlight. In addition to the modification in the material, the release of antimony ions was also identified through inductively coupled plasma mass spectrometry and the release of total organic carbon, proving the degradation. Through confocal microscopy, particles that were possibly PET were identified, indicating that photodegradation caused the release of fragments of the material. Preliminary toxicological analyzes indicated chronic damage to the D. magna organism, with microstructural changes observed through transmission electron microscopy and scanning electron microscopy. Oxidative stress tests demonstrated an oxidative effect on exposed organisms and through film analysis, changes in thoracic and cardiac movements and in the swimming behavior of the organisms were verified. No toxicological effects were observed on the marine bacteria A. fischeri.