EFEITOS GENOTÓXICOS DA ÁGUA RESIDUÁRIA DE SUINOCULTURA PROCESSADA POR BIODIGESTOR EM MODELOS ANIMAIS E VEGETAIS

Abstract

The destination of residues to biodigesters for crops fertilization and irrigation has araised as an economically viable alternative for agriculture, taking advantage of organic matter and nutrients from this residue for plant fertilization. However, its use has been questioned as it is very rich in macro and micronutrients and it may lead to adverse effects. The purpose of this work is to evaluate the genotoxic and cytotoxic effects of ARS in plant models (Allium cepa and Lactuca sativa), and in animal models, (Lithobates catesbeianus and Physalaemus nattereri) exposed to swine wastewater processed by the biodigester (SWB). For this, animal and plant species were exposed to SWB. In animal species, the behavior and frequency of micronuclei (MN) and other nuclear abnormalities (NA) were evaluated. In plant species, growth index, mitotic index (MI), chromosomal changes (CC) and nuclear abnormalities (NA) were evaluated. The results showed behavioral changes and the significant presence of MN and NA for both animal species indicating genotoxicity and cytotoxicity of the SWB for amphibians. In plant models, we found root growth inhibition in A. cepa, decreasing of MI and significant differences for chromosomal adherence, a type of CC, also pointing to cytotoxicity and genotoxicity of SWB in plant species. The observed toxicity can be caused by heavy metals existing in SWB, which is related with cholinesterase inhibition, causing behavioral changes in tadpoles. Addtionally, the heavy metals can impair cell division and promote NA and MN. In addition, these elements can cause oxidative stress in plants, by means of production of reactive oxygen species that affects the growth and development of plants, leading to CC and NA. Finally, we concluded that the SWB shows genotoxic and cytotoxic effects in animal and plants.