Chemical pollutants killing killer whales around the world, a new study warns. Persistent chemical pollution in the environment could wipe out half of the world’s populations of killer whales before the end of the century.
Published in the journal Science, the new study has found that the chemical pollutants, banned more than 40 years ago, remain a deadly threat to marine life.
Killer whales or orcas groups around the world may disappear entirely from several areas due to polychlorinated biphenyls (PCBs), which were once globally used in the production of carbonless copy paper as well as plastics, sealants, paints, and electrical equipment. But their production was banned decades ago in the US, but many industrial of the world areas still uses them.
Researchers have found levels of PCB as high as 1300 milligrams per kilo in the fatty tissue of some killer whales. Several studies have shown that just 50 milligrams per kilo PCB levels can cause infertility and severe immune system issues. The harmful effects of PCBs on fertility and immunity have already destroyed many orca populations.
“The findings are surprising. We see that over half of the studied killer whales populations around the globe are severely affected by PCBs” Jean-Pierre Desforges of Aarhus University in Denmark said in a statement.
“This suggests that the efforts have not been effective enough to avoid the accumulation of PCBs in high trophic level species that live as long as the killer whale does. There is, therefore, an urgent need for further initiatives than those under the Stockholm Convention,” concludes Paul D. Jepson, another killer whale expert, and co-author of the article.