2,3,7,8-substituted PCDDs and PCDFs in sea lion (Otaria flavescens) skin biopsies from two South-western Atlantic populations

Congener specific 2,3,7,8-chlorinated PCDDs and PCDFs were determined in sk in biopsies taken from sea lions (Otaria flavescens) living in two areas of the South-western Atlantic on the coast of Argentina (Mar del Plata and Pu nta Bermeja). This is the first report on PCDDs and PCDFs in sea lion skin biopsies from the southern hemisphere. Differences were found in the congen er pattern according to the sampling area. Animals living in the polluted a rea (Mar del Plata harbour) had detectable levels of all seventeen 2,3,7,8- substituted congeners. Sea lions living in a control environment (Punta Ber meja, Patagonia) only exhibited 5 detectable congeners out of all seventeen 2,3,7,8-substituted congeners. However, total levels were low in both colo nies studied. These data are consistent with previous work which has indica ted that dioxins occur at relatively low levels in marine mammals, possibly due to rapid catabolism or elimination. (C) 1998 Elsevier Science Ltd. All rights reserved.