Avaliação de metais em fêmeas e filhotes de podocnemis expansa (Schweigger, 1812; Testudines: Podocnemididae) em um trecho do médio rio Araguaia

Abstract

Human activities have contributed directly to the increase in the levels of metallic ions in ecosystems, mainly through mining, emission of domestic, industrial and agricultural effluents. The use of fertilizers and pesticides can be an important source of insertion of metals in the environment. Several studies have indicated that chelonians may reflect impacts caused by various contaminants, such as pesticides used in conventional agriculture. The Amazonian turtle (Podocnemis expansa) is a freshwater chelonian that represents food importance for the Amazonian populations, used legally and illegally by riverside and urban populations. The present study detected and quantified nine metals; Al; CD; Cr; Ass; Faith; Mn; Ni; Sn and Zn, in Females and Pups P. expansa during the reproductive period. We also performed the quantification of metals in the sediment of the nests of each female, to identify a possible route of contamination. The micronucleus test was performed to evaluate the genotoxicity of these metals present in P. expansa cells. The results showed that females and offspring had concentrations of metals higher than those found in several studies with reptiles. We can also observe an increase in Sn metal concentrations along the Araguaia basin. The results of metal concentrations in the sediment were lower than the VRQ's of several states, however, we were able to notice an increase in the concentrations of metals Al, Cr and Fe along the Araguaia River basin. It was also possible to observe a correlation between the metal Mn in the sediments with the values found in the liver of the puppies. The micronucleus test indicated a high rate of damage to the genetic material, but it was not possible to trace a correlation between the studied metals, however we observed a correlation between the micronuclei and the size of the females. Therefore, the results are preliminary, and the future quantification of metals in eggs, juveniles and males of the species becomes essential, as they will be able to elucidate the real interaction of these metals with the populations in the study area, pointing to possible deleterious effects on health and reproduction. of these individuals. Finally, we can conclude that P. expansa can be considered as a bioindicator in the assessment of environmental risks, and that despite the study area being located between important Conservation Units, the results indicate that these areas are also subject to anthropic influences