ORGANOCHLORINE, ORGANOBROMINE, METAL, AND SELENIUM RESIDUES IN BOTTLE-NOSED DOLPHINS (TURSIOPS-TRUNCATUS) COLLECTED DURING AN UNUSUAL MORTALITY EVENT IN THE GULF-OF-MEXICO, 1990

Polychlorinated biphenyls (PCBs), cis-chlordane, oxychlordane, heptach lor epoxide, mirex, hexachlorobenzene (HCB), lindane, octachlorostyren e (OCS), p,p'-DDE,p,p'-DDT, dieldrin, triphenylphosphate (TPP), polybr ominated biphenyls (PBBs), and polybrominated diphenyl ethers (PB-DPEs ) were measured in the blubber, and five metals (mercury, lead, cadmiu m, chromium, and manganese) and selenium were measured in the liver of bottlenose dolphins (Tursiops truncatus) obtained from the Gulf of Me xico during an unusual mortality event in 1990. The collection of anim als included fetuses, sucklings (<1 year old), immature dolphins (2-5 years old), and adults of both sexes. PCBs, p,p'-DDE, HCB, and PBDPEs were detected in the blubber of each animal. Mean concentrations of or ganic contaminants were generally highest in adult males. p,p'-DDE was the single component analyte measured at the highest concentration. I mmature females had greater concentrations of most chlorinated organic s than adult females. Mercury and cadmium concentrations in liver incr eased with increasing age-class. The correlation between mercury and s elenium in all animals was r = 0.96, with a mole ratio of 0.90. Concen trations of lead, manganese, cadmium, and chromium did not follow any particular age-class trend.