Trace elements in different species of cetacean from Rio de Janeiro coast

Tércia G Seixas,Cristina M M Souza,Ana Paula M Di Beneditto,Helena A Kehrig,Isabel Moreira,Olaf Malm

doi:10.1590/s0103-50532009000200008

Abstract

The present work tested whether ecological and biological parameters have an influence on the accumulation of trace elements (As, Cd, Cu, Pb, Se and Ag) by the liver of three cetaceans species: two species of coastal habit (Pontoporia blainvillei and Sotalia guianensis) and one of oceanic habit (Stenella frontalis), that were incidentally caught in fishing nets along the north of Rio de Janeiro coast. Inter-species difference was observed on the accumulation of Cd and Pb (5.12 ± 0.74 µg g-1 and 21.25 ± 1.35 µg g-1, respectively). However, the three cetacean species, S. guianensis, P. blainvillei and S. frontalis presented similar hepatic concentrations of As, Cu and Ag. No gender differences were found on the bioaccumulation of trace elements. Hepatic trace element accumulation was influenced by body length, according to the cetacean species. S. guianensis, which co-habits the same coastal marine environment that P. blainvillei species, presented a significant difference between hepatic selenium concentration (20.70 ± 32.22 µg g-1 and 3.24 ± 2.02 µg g-1, respectively). Based on these results, it is possible to conclude that, not only the different environmental conditions, but also total length and mainly the feeding habit influenced the accumulation of trace elements by the liver of these cetacean species.

Highlights

The industrial and urban development observed in the last decades greatly increased the fluxes of various chemical ArticleTrace Elements in Different Species of Cetacean from Rio de Janeiro Coast can be considered detrimental at excessive levels.[3,4] living organisms require varying amounts of metals
Cd and Pb concentrations in the liver of the cetacean species that occur on continental shelf (S. frontalis) were significantly higher than those found for S. guianensis (p < 0.001) and P. blainvillei (p < 0.001)
Due to the small sample population of the cetacean species that occur on continental shelf (S. frontalis), discussion about gender and body length differences in hepatic trace element concentrations was confined to cetaceans with coastal habits, S. guianensis and P

Summary

Introduction

The industrial and urban development observed in the last decades greatly increased the fluxes of various chemical ArticleTrace Elements in Different Species of Cetacean from Rio de Janeiro Coast can be considered detrimental at excessive levels.[3,4] living organisms require varying amounts of metals. The study of trace elements in marine mammals is in its infancy in Brazil where few studies documented their concentrations in the tissues of cetaceans species with coastal habits such as Sotalia guianensis, Pontoporia blainvillei and oceanic habits such as Stenella frontalis.

Results

Conclusion