Investigação dos teores de metais pesados em espécies de siris azuis do gênero Callinectes sp.

Abstract

IntroduçãoUm dos aspectos críticos da introdução de substâncias químicas em sistemas aquáticos é a sua bioacumulação na cadeia alimentar existente nestes compartimentos ambientais, principalmente, no que se refere à contaminação por metais pesados (MARKERT, 1998).No município de Cubatão foram instaladas, a partir da década de 1950, importantes indústrias petroquímicas, metalúr-gicas, fertilizantes, entre outras, aproveitando-se das facilidades do maior porto marítimo do País, o Porto de Santos. O material poluente lançado na região por essas indústrias levou a um processo de degradação ambiental intenso na região. Na década de 1980, a CETESB-Companhia de Tecnologia de Saneamento Ambiental (SP) implantou um programa rígido de controle de poluição ambiental no município de Cubatão, o que reduziu drasticamente a ocorrência de episódios críticos de poluição do ar e tornou possível a recuperação da qualidade das águas. Contudo, estudos realizados pela própria CETESB (1990) utilizando amostras de águas, sedimentos e organismos aquáticos provenientes da bacia do rio Cubatão, constataram ainda a presença de alguns metais pesados e compostos orgânicos em concentrações muitas vezes superiores aos limites recomendados pela WHO (1972). No último relatório publicado pela CETESB (2001), os resultados mostraram uma redução (maior que 50%) da contaminação nos organismos, em relação aos estudos anteriores, para alguns metais (cádmio, chumbo, mercúrio) e alguns compostos orgânicos (hexaclorobenzeno). Como conseqüência, observou-se o retorno de peixes e outros organismos aquáticos, que haviam emigrados da bacia do rio Cubatão. Entretanto, esta transformação ambiental na região não garante a ocorrência de uma recuperação total dos corpos d'águas, já que alguns compostos químicos, entre eles os metais pesados, permanecem nestes ambientes, principalmente nos sedimentos, por longos períodos de tempo AbstractUsually, heavy metals occurrence in aquatic systems is resulting from natural geochemical processes. However, the presence of these chemical elements has considerably increased in the last decades . An example is the case of the Cubatão river basin caused by human activities in that region. In this work, a quantitative analysis of Pb, Cd, Cr, Zn, and Cu content of four blue crab species of the genus Callinectes sp., sampled along the Cubatão river, was carried out using a flame atomic absorption spectrometer (FAAS). 144 blue crab samples from the following species were analyzed: C. danae (63%), C. sapidus (23%), C. bocourti (10.5%), and C. ornatus (3.5%). The C. Sapidus species presented the highest concentration levels for the studied metals. With the exception of Cu, for which the average concentration was 40% higher for the females (p < 0,05), there was no significant variation in the heavy metal content regarding sex and the size of the animals. Except for Cr, for which the average values interval obtained for the 4 species was above the limit allowed by the Brazilian legislation for any type of food, all the other results were...

A Preliminary Assessment of Metal Bioaccumulation in the Blue Crab, Callinectes danae S., from the Sao Vicente Channel, Sao Paulo State, Brazil

“…Harris and Santos (2000) also found high concentration of Zn in the hepatopancreas of C. danae, however, Cu, Cd and Fe concentrations were higher in this tissue than in others. Cd, Cr, Cu, Pb and Zn concentrations obtained in this study were similar to those found by Virga et al (2007) and Virga and Geraldo (2008) in muscles of C. danae collected in the Cubatão River, Brazil. Reichmuth et al (2010) also found high concentrations of Hg in muscles and high concentrations of Zn in hepatopancreas of Callinectes sapidus.…”

“…Virga et al (2007) and Virga and Geraldo (2008) have already investigated the concentrations of Pb, Cd, Cr, Zn and Cu in individuals of genus Callinectes (including C. danae) from Cubatão River. Besides these studies, few information was published about this species and its relationship with metals released in the Santos Estuarine System, although many studies recorded high concentrations of metals in the local sediment (the species' habitat) (Bordon et al 2011). Thus, this study is a preliminary assessment of metals in tissues of C. danae from the São Vicente Channel, Brazil, aiming to determine the bioaccumulation process of this species.…”

First assessment of trace metal concentration in mangrove crab eggs and other tissues, SE Brazil

“…Nevertheless, in both study areas, metal concentrations were inversely proportional to crab size in most cases. This was also observed in other studies, besides a result from different physiological lifelong requirements (Virga and Geraldo 2008). Meanwhile, Ucides cordatus crabs from other mangroves of Southeastern Brazil did not show significant correlations between Cu, Cd, Cr, and Mn concentrations and CW (Pinheiro et al 2012).…”

Implications on the Pb bioaccumulation and metallothionein levels due to dietary and waterborne exposures: The Callinectes danae case

“…Few previous studies have assessed metal concentrations in C. danae tissues for biomonitoring purposes (Virga et al, 2007;Virga and Geraldo, 2008;Bordon et al, 2016); some have reported that different metals may present different target tissues and bioaccumulate differently in distinct tissues (Bordon et al 2012b;Lavradas et al, 2014). The combination of the uptake and depuration processes of each tissue and in the whole organism would lead to the following processes: metals can be efficiently excreted, can accumulate in immobilized form, or can remain active in the tissue and lead to deleterious effects in the animals (Rainbow, 1988(Rainbow, , 1998(Rainbow, , 2007(Rainbow, , 2002.…”