RECENT CHANGES IN LEVELS OF PERSISTENT ORGANOCHLORINES AND MERCURY INEGGS OF SEABIRDS FROM THE BARENTS SEA

Eggs of ten seabird species were collected from six regions in North N orway, Svalbard and NW Russia in 1993, and were analyzed for organochl orines (OCs) and mercury. Significant declines in levels of PCBs, p,p' -DDE, HCB, beta-HCH, gamma-HCH and oxychlordane were documented in nea rly half the data set since a similar study in 1983 in six of the seab ird species breeding in North Norway. Only four of the 90 paired data sets increased significantly, and the remainder remained unchanged. Th ere was very little change in mercury levels. The decline in OCs corre sponds to similar declines found in Canada and the Baltic Sea, and to declines documented in marine fish in a Norwegian fjord They can all b e attributed to the reduction in use and spread of contaminants, both in Norway and internationally. No consistent regional differences in r esidue levels were found.