“Test Tube Cetaceans”: from the Evaluation of Susceptibility to the Study of Genotoxic Effects of Different Environmental Contaminants Using Cetacean Fibroblast Cell Cultures

Population estimates of various species of cetaceans indicate that certain species have declined dramatically this century. Most studies of contamination and biomarker responses in marine mammals have been conducted using animals killed by hunting, tacitly approving this activity. The development of a series of nondestructive techniques to evaluate biomarker responses and residue levels is strongly recommended for the hazard assessment, protection and conservation of endangered species of marine mammals. A non-invasive sampling method, represented by skin biopsy or integument biopsy (epidermis, dermis and blubber), have been developed and validated in cetaceans. In this paper we present the cetacean fibroblast cell cultures obtained from the skin biopsies as the “test tube cetacean” for evaluate both the susceptibility that the genotoxicity of different environmental contaminants. Fibroblast cell cultures were obtained from many species of cetaceans sampled in Mediterranean Sea (Italy) and in the Mar de Cortez (Mexico). Using test tube cetaceans we can study the relationships between contamination and biochemical responses. One of the principal applications of this developed in vitro system was the assessment of interspecies differences in the mixed function oxidase activity (Cyp1A1 and Cyp2B) induced by in vitro treatment of various contaminants, such as some Persistent Organic Pollutants (POPs) but also emerging contaminants (such as bisphenol A (BpA)) and nanoparticles, added at different concentrations. The induction of Cyp1A1 and Cyp2B was evaluated with the indirect immunofluorescence technique. Therefore, another purpose of this work was to evaluate the qualitative and quantitative MICA protein expression in fibroblast cell cultures with immunofluorescence technique as toxicological stress marker of the immune system of different species of cetaceans. Finally, In this paper we will present how to evaluate the presence of DNA damage by comet assay in test tube cetaceans, after treatment with different genotoxic compounds (for example PCBs, DDTs, PAHs, BPA).