RESUMEN
In the present study, water physicochemical and microbiological parameters, as well as bioassays using Allium cepa L. seeds and the fish species Astyanax jacuhiensis were used to assess the water quality of two rivers - Ilha River and Paranhana River -, located in southern Brazil. Water samples were collected at the source and mouth of the rivers and then, laboratory experiments were performed. The results evidenced high levels of aluminum and iron in water samples collected at the four sampling sites. The micronucleus (MN) test in fish showed significant difference in the frequencies of nuclear abnormalities (NA) in the mouth of the Paranhana River in comparison to control group in one sampling period, whereas the A. cepa test evidenced significant spatial differences in cytotoxicity between the source and mouth of both rivers. Therefore, these data evidence the poor water quality of the rivers studied as well as the potential toxicity to the aquatic organisms.
Asunto(s)
Characidae , Contaminantes Químicos del Agua , Animales , Bioensayo , Brasil , Monitoreo del Ambiente/métodos , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Calidad del AguaRESUMEN
Root resorption seems to be related to a complex combination of mechanical factors and biological activity, which comprehends the role of immunologic structures including specialized cells. The aim of this research was to explain the development of the process--from mineralization to the destruction of hard tissues--and the possible relationship between root resorption and immunology, along with discussing current concepts described in the literature.