Search

Morphological, structural and compositional alterations in shells of molluscs have been proposed as putative biomarkers of chemical contamination in coastal zones. Despite this, few studies were carried out using top predator gastropods which tend to be more susceptible to contamination exposure. Thus, the present study assessed disturbances on shells of Stramonita brasiliensis considering compression resistance and organic and mineralogical matrix composition, related to morphometric alterations. Results showed reductions in compression resistance and organic matrix content associated with higher contaminated sites. In addition, a predominance of calcite polymorphs was seen in shells obtained in polluted areas. Such outputs were consistent with local contamination levels which may have induced the observed alterations. Thus, changes in mollusc shells showed good performance as potential biomarkers of coastal contamination, being probably observed in other species of carnivorous gastropods around the world.

Magellanic penguins, Spheniscus magellanicus, are the most abundant penguins living in temperate regions of South America and are good indicators of environmental pollution in the region. Persistent organic pollutants (POPs) were detected in the liver of Magellanic penguins found debilitated or dead on the beaches of Brazil (states of Rio de Janeiro, Sao Paulo, Santa Catarina and Rio Grande do Sul) between 2008 and 2012 as well as in Uruguay and Chile in 2011. Polychlorinated biphenyls (PCBs) were more prevalent than organochlorine pesticides (DDTs ∼ HCB ∼ Drins) and polybrominated diphenyl ethers (PBDEs). Among PCBs, penta-, hexa- and hepta-chlorinated congeners were predominant. Concentrations of POPs were similar between the Pacific and Atlantic penguin populations, except for PCBs, which were relatively higher in the Pacific population. During the study years (2008-2012), large variations were found in organochlorine pesticides and PCBs tended to decline. Overall, the southern portion of South America has low concentrations of POPs, with either a constant trend or evidence of decline.

Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyls Ethers (PBDEs) are two highly lipophilic classes of persistent organic pollutants able to resist degradation and with the ability to bioaccumulate through the food chain. In Brazil, there are still few studies on PCBs and PBDEs in aquatic organisms. In this study, we determined the levels of PBDEs and PCBs in three different fish species from the Ilha Grande Bay, located in the southern state of Rio de Janeiro, Brazil. PBDEs levels were very low, with values below the limit of quantification. PCBs concentrations ranged from 2.29 to 27.60 ng g(-1) ww in muscle and from 3.41 to 34.22 ng g(-1) ww in liver of the three investigated fish species. Significant positive correlations were established between PCBs concentration and fish biometric variables in mullet (length and lipid content) and a statistically significant change between seasons in croaker was observed.