The use of non destructive biomarkers in the study of marine mammals

Abstract

Marine mammals have been subject to heavy anthropogenic pressure by direct killing and chemical pollution all over the world. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting out of a total of 12 cetacean species studied, 45 of the specimens were obtained by sacrificing the animal; out of a total of eight pinniped species studied, 40 of the specimens were obtained by killing. The development of a series of non destructive techniques to evaluate biomarker responses and residue levels is recommended for the hazard assessment and conservation of endangered species of marine mammals. Here we review the current status of the non destructive biomarker approach in marine mammals, describing the biological materials available for non destructive tests in stranded brain, liver, blood, skin, subcutaneous blubber, muscle and fur and free ranging animals blood, skin biopsy, fur and faeces and the respective biomarker techniques mixed function oxidase activity and DNA damage in skin biopsy samples; porphyrins in faeces and fur; esterases, porphyrins, clinical biochemical parameter, vitamin A and micronuclei in blood samples. Residue analysis can be carried out in the various biological materials. We also report the results of applying this methodological approach to cetaceans minke whale Balaenoptera acutorostrata, fin whale-- Balaenoptera physalus, beluga whale-- Delphinapterus leucas, short finned pilot whale-- Globicephala macrorhynchus, harbour porpoise -- Phocoena phocoena, Rissos dolphin-- Risso s Grampus griseus, Dall s porpoise-- Phocoenoides dalli dalli, melon headed whale-- Peponocephala electra, bottlenose dolphin -- Tursiops truncatus, striped dolphin-- Stenella coeruleoalba, spinner dolphin-- Stenella longirostris, killer whale-- Orcinus orca and pinnipeds northern fur seal- Callorhinus ursinus, hooded seal-- Cystophora cristata, grey seal-- Halichoerus grypus, harbour seal-- Phoca vitulina, ringed seal-- Phoca hispida, harp seal-- Phoca groenlandica, ribbon seal-- Phoca fasciata, largha seal- Phoca largha, southern sea lion-- Otaria flavescens in field studies for prognostic and diagnostic purposes.

Keywords::

• Biomarkers, Marine Mammals, Endangered Species, Ecotoxicological Risk, Contaminants