CONTAMINATION BY BUTYLTIN COMPOUNDS IN HARBOR PORPOISE (PHOCOENA-PHOCOENA) FROM THE BLACK-SEA

Concentrations of butyltin compounds (BTs) were determined in harbour porpoise (Phocoena phocoena) collected from the Turkish coastal waters of the Black Sea. Total butyltin compounds (Sigma BTs) in the liver w ere in the range of 89-219 ng/g on a wet weight basis. The dibutyltin (DBT) residues were higher than those of tributyltin (TBT), suggesting the degradation of TBT to DBT in the liver and the metabolic capacity comparable to other marine mammals. Any sex difference and age-depend ent accumulation of BTs residues were not found in harbour porpoises, but residue levels increased until maturity and then remained constant . When compared with other marine mammals, the present results indicat e that the Black Sea is also contaminated with butyltin compounds, but to a lesser degree than coastal waters of developed nations. The biom agnification factor in harbour porpoises was 0.8, which was comparable with pinnipeds and lower than cetaceans.