Nuclear abnormalities in erythrocytes and morphometric indexes in the catfish Cathorops spixii (Ariidae) from different sites on the southeastern Brazilian coast

Abstract

Nuclear abnormalities in erythrocytes (NAE) were taken as biomarkers in the catfish Cathorops spixii (Ariidae) sampled in an estuary little affected by human activity (Cananéia) and in three regions (Santos Channel: SC, Santos Bay: SB and São Vicente Channel: SVC) of the Santos-São Vicente estuary impacted by various anthropogenic activities. Increases in NAE were observed in fish from SC and SVC sampled in the summer period as compared with specimens from the Cananéia estuary. These results suggest the presence of genotoxic compounds in these regions. However, the absence of significant differences in micronuclei frequency reflects slight mutagenic effects in these individuals. It is possible that the lower NAE frequency in specimens from SB might be associated with the greater remobilization and dilution of chemicals in this region. The low frequency of NAE in C. spixii from the Cananéia estuary is in accordance with the slight anthropogenic influence in this system, and may be suggestive of the absence of genotoxic and mutagenic effects in these organisms.<br>Alterações nucleares eritrocitárias (ANE) foram consideradas como biomarcadores nos bagres Cathorops spixii (Ariidae) amostrados em um estuário com baixa influência humana (Cananéia) e em três regiões (Canal de Santos: CS, Baía de Santos: BS e Canal de São Vicente: CSV) no estuário de Santos-São Vicente, impactado por diversas atividades antropogênicas. Aumentos nas ANE foram observados nos peixes amostrados no CS e CSV durante o período de verão, quando comparados com os espécimes do estuário de Cananéia. Estes resultados sugerem a presença de compostos genotóxicos nessas regiões. Entretanto, ausência de diferenças significativas na freqüência de micronúcleos refletem baixos efeitos mutagênicos nesses indivíduos. As menores freqüências de ANE nos espécimes amostrados na BS podem estar associado à maior remobilização e diluição dos compostos químicos na região. A baixa freqüência de ANE em C. spixii do estuário de Cananéia corrobora a menor influência antropogênica nesse sistema, e pode estar sugerindo ausência de efeitos genotóxicos e mutagênicos nos organismos

Trace Elements and Nuclear Abnormalities in Fish Species of Two Brazilianestuarine Regions – An Attempt to Increase the Matrix for Environmental Monitoring

“…NAE are sensitive non-specific indicators of mutagenic damage, they can however provide an additional tool for the understanding of the genotoxic effect and have been used by some authors in biomonitoring studies [15,26,27]. In the four species analyzed (M. americanus, M. furnieri, C. faber and P. brasiliensis) in relation to the expression of genotoxic effects, C. faber was the most responsive since it showed a more significant NAE, as well as clastogenic effects expressed with a greater frequency of micronuclei.…”

“…The Ariidae catfish, Cathoropsspixii, has been validated as a bioindicator species for exposure to metals in natural aquatic ecosystems such as estuarine systems [13,14] and the genotoxic effects in this fish submitted to different degrees of anthropogenic influence has been observed [15]. Taking into account the potential damage to environmental conditions, no target species were pre-defined in this present study, instead all the species caught, with the exception of Cathoropsspixii (catfish) -the focus of another study [13,16] -were investigated.…”

Zn, Co, Cr, As, and genotoxic effects in the ichthyofauna species from polluted and non-polluted/protected estuaries of the São Paulo coast, Brazil

“…In the last decade, Cathorops spixii have been used as bioindicators of contamination in SSV and CAN, since they accumulate and participate in the dynamics of essential and nonessential metals, such as Zn, Cu, Mn, Fe, Hg, Pb, Cd, and Ni (Azevedo et al 2012a). Besides, C. spixii responds to biochemical, histopathological (Azevedo et al 2013), and genotoxic effects by nuclear abnormalities in erythrocytes alterations (Azevedo et al 2012b) and these studies showed greater damage to catfish from SSV than the CAN estuary.…”

Using a tiered approach based on ecotoxicological techniques to assess the ecological risks of contamination in a subtropical estuarine protected area

“…The CIP estuarine complex has been considered uncontaminated by some authors (Azevedo et al, 2012); however, other studies have reported moderate to high concentrations of metals in sediments from the region (Cruz et al, 2014), especially close to the Valo Grande Channel (Aguiar et al, 2008;Mahiques et al, 2009;Saito, 2002;Guimarães and Sígolo, 2008b). In the northern portion of CIP estuarine complex, there is a consensus that the mining and metallurgical activities that took place in the upper parts of the RIR basin represent the main source of metals, and that the Plumbum Company was the main contributor of Pb, Cu, Zn and Cr to the system (Guimarães and Sígolo, 2008a;Piedade et al, 2014), along with a set of mines that were spread out across the region.…”