Effects of association between titanium dioxide nanoparticles and different pH in gills chloride cells s density and proliferation

Abstract

The use of nanoparticles (NP) such as titanium dioxide (TiO2) has increased in recent years due to their use in the manufacture of foods, cosmetics, pharmaceuticals and sunscreens. The absence of disposal standards of these nanomaterials makes them can reach the aquatic ecosystems and cause changes in biota. In addition, abiotic factors of the aquatic environment, such as temperature, pH, oxygen content, hardness and organic matter, can modify the physicochemical characteristics of NP- TiO2 and affect the fish that inhabit this ecosystem. The gills are the first organs to contact to xenobiotics in the water, wich is absorbed, can change the functions of these tissue. The use of scanning electron microscopy (SEM) provide detailed information on the surface of the epithelium and allows a very thorough analysis of the density, shape and area of existing mitocôndria-rich cells (MRCs) in the gill epithelium and cellular responses in a xenobiotic. Thus, the present study aims to investigate the effects of exposure to sublethal concentrations of NP-TiO2 at different pH (acid, neutral and basic) in juvenile P. lineatus, from the determination of density and fractional area of MRCs in gills using the resources of the SEM.