Interações de micropartículas de TiO2 com os sistemas biológicos Lactuca sativa L., Artemia salina e Danio rerio

Abstract

Nanostructured materials have revolutionized modern life. Numerous compounds have undergone size reduction processes and have been reintroduced into sectors such as health, cosmetics, food, agriculture, technology, and others. The compound used in this work is titanium dioxide microparticles (TiO2MPs). It is a metal produced on a large scale and used in sunscreen formulations, in food as a colorant, in aquatic depollution strategies, among others. The objective of this work was to characterize the effects of titanium dioxide toxicity on biological systems. The three models chosen were: Lactuca sativa L., Artemia salina, and Danio rerio. Experiments were carried out exposing the models to different concentrations: lettuce to 50 mg.L-1 TiO2MPs, artemia to 12.5, 25, 50, and 100 mg.L-1 TiO2MPs, and zebrafish to 1, 10, and 100 mg.L-1 TiO2MPs. The results were analyzed using conventional optical microscopy, scanning electron microscopy, and transmission electron microscopy. Anatomical and ultrastructural damage confirmed the compound's toxicity to lettuce. In artemia, it caused a high mortality rate in addition to cellular damage at concentrations of 25, 50, and 100 mg.L-1 TiO2MPs. In zebrafish, however, there was no mortality or high rate of deformation. TiO2MPs showed toxicity dependent on concentration, time, and biological model. Even without confirmed absorption, direct contact causes cellular and structural damage in plants and animals. The results highlight the importance of chronic studies under realistic environmental conditions to assess the impact of TiO2MPs on ecosystems and food chains.