PCBs, polychlorinated biphenyls, were once used in everything from electrical supplies and plastics to flame retardants and paints. But once it was discovered that they were highly toxic to wildlife and humans, they were banned.
Even though the chemicals were banned, they are still having a detrimental effect, persisting in the environment and accumulating in top predators. Products such as old electrical wiring and paints containing PCBs are still being disposed of in landfills, where they eventually are leached into streams and estuaries, reaching the marine environment.
The Christian Science Monitor reports, “We think there is a very high extinction risk for killer whales as a species in industrialized regions of Europe,” said Paul Jepson, a wildlife veterinarian from the Zoological Society of London, who led a study on the effects of PCBs.
Jepson, in a telephone interview with CSM, said the future is looking bleak for orcas and dolphins in European waters, adding, “We think there is a very high extinction risk for killer whales as a species in industrialized regions of Europe.”
The BBC is reporting that for the study, researchers took samples from 1,000 animals, and found that PCB levels of cetaceans in Europe were the highest found in the oceans. Jepson said, “For striped dolphins, bottlenose dolphins and killer whales, we have mean PCB levels that are excessive – they are really high – probably the highest in the world right now. Europe is a big big hot-spot.”
Jepson is worried that killer whales will become extinct in Europe if something isn’t done to curb the way PCBs are being disposed of in landfills. As the chemicals leach into the marine environment, they eventually make their way up the food chain, accumulating in the cetacean’s blubber.
There are two European hot-spots where PCBs are extremely high, the western Mediterranean Sea and south-western Iberian Peninsula. The contamination is playing havoc on the breeding success of the orcas, and particularly on the calves. A nursing calf will ingest almost 90 percent of its mother’s contamination.
“There are only eight killer whales left around the west of Scotland and Ireland,” said Dr. Jepson. “This is a population studied for many years, and there has not been a calf in all the years that this group has been studied so that population will go extinct.”
On Jan. 8, Digital Journal reported on the death of Lulu, an orca found dead on the beach of a Scottish island. While her death was attributed to being caught up in fishing line, she was the last of a pod that was on the verge of extinction.
In November 2015, Digital Journal reported the city of Oakland, California is suing Agrotech giant, Monsanto. The lawsuit holds the company accountable for allegedly contaminating the city’s storm-water as well as the San Francisco Bay with polychlorinated biphenyls (PCBs).
The research team says there clearly needs to be something done to either remove or seal off PCB-laden waste in landfills. They suggest global regulations need to be enacted to protect our environment.
The study, “PCB pollution continues to impact populations of orcas and other dolphins in European waters,” was published in the journal Nature on January 14, 2016.
