New research shows that the levels of PCBs in polar bear cubs in Svalbard
have decreased by up to 59% between 1998 and 2008.
"The levels of PCB compounds in blood samples from females are on the
decline," says Jenny Bytingsvik, a biologist at the Norwegian University of
Science and Technology who is completing her doctoral dissertation on the
findings. "For newborn, vulnerable cubs, this is a very positive trend.
Reduced levels of PCBs in the mother bears' blood mean that there is also
less contamination in their milk. Even though the PCB levels we found are
still too high, this shows that international agreements to ban PCBs have
had an effect."
The PCBs are fat-soluble chemicals and the higher up the food chain, the
higher the concentration of pollutants. The polar bear, which feeds mainly
on high-fat animals such as seal, is therefore especially exposed.
The production of PCBs has been banned internationally since 2004.
