UK killer whales and bottlenose and striped dolphins are at the risk of extinction, claims a study. The study which is published in the journal Scientific Reports, said that UK’s last pod of killer whales could go extinct due to the high level of PCB pollution.

PCBs or polychlorinated biphenyls contaminate the environment by producing dangerous byproducts like hydrogen chloride and dioxins.

According to Eco Watch, the contamination has affected their reproductive system. The result is already visible, as some species of European resident whale and dolphin population have been extinguished. Scientists have claimed that other species including a pod of killer whales would also vanish soon.

Reportedly, just eight individuals are there in the pod of killer whales off the coast of UK  and they have stopped giving birth since 1990.

The chemicals which were used in electrical equipment and banned in 1980s are still leaking into the ocean. The research claimed that bottlenose and striped dolphins and killer whales carried an extremely high amount of the chemicals in their body. The researchers have found that it caused many health issues in these mammals including failure of the reproductive system.

After the 1980s ban, the level of PCB declined in marine mammals of the US, but it did not happen in the case of their European counterparts. Meanwhile, Paul Jepson of the Zoological Society of London and the study’s lead author said, “the levels are very high, probably the highest in the world right now.”

He added, “The answer to that is neither easy nor straightforward. But mitigation measures should really involve dealing with historic and current industrial uses in old equipment—transformers and things, in electrical equipment—PCBs leaking out of landfill into rivers, PCBs in marine sediments, which are often dredged to keep shipping lanes open, which makes them more bio-available to get into the marine food chains”.

Jepson further emphasized that the species would go extinct, but when that would happen could not be said. Killer whales live for 50 years and sometimes 90 years. However the age of the pod are not known.