PCB pollution threatens to wipe out killer whales

More than 40 years after the first initiatives were taken to ban the use of PCBs, the chemical pollutants remain a deadly threat to animals at the top of the food chain. A new study shows that the current concentrations of PCBs can lead to the disappearance of half of the world’s populations of killer whales from the most heavily contaminated areas within a period of just 30-50 years.
Source: Science Daily