RESUMO
The development of methodologies for biomonitoring freshwater ecosystems is of particular relevance in view of the serious problem of aquatic environmental pollution. The mussel species Limnoperna fortunei (golden mussel) was chosen to be tested as a biomonitor organism based on its population data and distribution. L. fortunei individuals were exposed to UV radiation in vitro, and in vivo to pentachlorophenol (PCP) and copper sulphate (CuSO(4)), with the aim of standardizing comet assay and micronucleus test methodologies and evaluating the potential of this organism as a biomonitor. Haemolymph cells immobilized in agarose on slides exposed to UV radiation showed a dose-response relationship with maximum damage at 4.2 J/m(2). For the chemical tests, individuals were exposed for 2h for the comet assay and 24 and 48 h for the micronucleus test. A dose-response relationship was observed for both chemicals. 3x10(-5) M CuSO(4) induced high genotoxicity, also producing some toxicity after 48 h of exposure. PCP induced maximum damage in both assays at 150 µg/L. Individuals exposed to PCP showed 100% repair 2 h after the exposure period, as assessed by the comet assay. Exposure to an environmental sample over 7 days confirmed the mussel sensitivity to water contaminants, detected both by the comet assay and the micronucleus test. The results allow us to suggest the golden mussel as a potential biomonitor organism.
Assuntos
Bivalves/efeitos dos fármacos , Sulfato de Cobre/toxicidade , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Hemócitos/efeitos dos fármacos , Pentaclorofenol/toxicidade , Animais , Bivalves/genética , Bivalves/efeitos da radiação , Células Imobilizadas , Ensaio Cometa , Dano ao DNA , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Hemócitos/citologia , Hemócitos/efeitos da radiação , Testes para Micronúcleos , Sefarose/química , Raios UltravioletaRESUMO
High doses of gamma radiation (10 Krad) in Biomphalaria tenagophila snails (Taim strain), which have been found to be resistant to Schistosoma mansoni, were not sufficient to impair their resistance to the parasite. The number of hemocytes, as well as their phagocytic activity, were not affected by irradiation, thus showing resemblance with mammal macrophages, which are resistant to gamma irradiation also.