AKIPRESS.COM - There are thought to be fewer than 10 killer whales inhabiting the waters around the British Isles, Sky News reports.

Half of the earth's killer whale population could be destroyed in decades by toxic chemicals being dumped in oceans, scientists warn.

Polychlorinated biphenyls (PCBs) previously used to make electrical parts and plastics are still highly prevalent in some parts of the ocean, despite them being banned by most countries.

Killer whales accumulate the toxic chemicals when they eat seals and large fish that have ingested them.

Now a global team of experts, including scientists from the Zoological Society of London (ZSL), are warning the current toxic concentrations could lead to destruction of 50% of the world's orca populations in the next 30-50 years.

Their findings, published in journal Science, saw declines in the number of killer whales in 10 out of the 19 populations examined.