And the seas around the UK are some of the most polluted in the world, researchers from Zoological Society of London (ZSL) and Aarhus University found.
More than 40 years after PCBs – or polychlorinated biphenyls – were banned, experts said they were still posing a deadly threat to orcas in the wild.
Researchers measured values as high as 1,300 milligrams per kilo in the blubber of killer whales. For comparison, a large number of previous studies have shown that animals with PCB levels as low as 50 milligrams per kilo of tissue may show signs of infertility and severe impacts on the immune system.
Dr Paul Jepson, co-author of the study from ZSL’s Institute of Zoology, said the PCB problem in Europe was “about as bad as it could possibly get”.
The chemicals have been used around the world since the 1930s, with more than a million tonnes produced and used in a variety of products including electrical components and plastics.
In the UK, numbers of orcas and dolphins have plummeted, with the killer whale population off the coast of Scotland down to just eight.
ZSL conservationists said the pollutants threatened to “wipe out” the species in a “killer whale apocalypse”.
Killer whales, whose diet includes seals, tuna and sharks, had the highest PCB concentrations and it is these populations that are at the highest risk of population collapse, the study found. Killer whales that primarily feed on small-sized fish such as herring and mackerel had a significantly lower content of PCBs.
However, in the oceans around the Faroe Islands, Iceland, Norway, Alaska and the Antarctic, the prospects are not so gloomy, the researchers found.
Toxic chemical pollutants could trigger a "killer whale apocalypse" with the species likely to disappear entirely from parts of the world’s oceans within just a few decades, conservationists have warned.
Orka and his partner Flix ran the Office of Acquisitions, a starship parts shop on the Colossus platform. Of the pair, it was Orka who took care of negotiations.  They had a DUM-series pit droid named GL-N who assisted them. 
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Orka and Flix were later present at their shop when Xiono visited to purchase a CX-19 compressor. The two giggled with Orka asking if Kaz had brought credits this time. While Kaz was purchasing the compressor, the two took an interest in Kaz’s lucky trophy but the youth refused to part with his prize, which he had won during a space race. Orka responded that Xiono could live comfortably for a few months if he sold his trophy. Xiono reiterated his refusal to sell his trophy. 
As the First Order occupation grew more repressive, Orka and Flix came up with a plan to escape the Colossus by smuggling themselves in a crate with their pet Gorg Bitey and and GL-N to Flix’s mother on Talivar. They encountered Kaz and CB-23, who were on a mission to free Yeager and liberate the Colossus. Orka and Flix were skeptical that Kaz’s plan would succeed. However, they were proven wrong and Kaz’s resistance cell not only succeeded in expelling the First Order but taking the Colossus into hyperspace. 
When Orka and Flix returned, they expressed shock at the messy state of their shop. Kaz related to them Teroj’s attempted heist of the phase connector. Orka praised Kaz for preventing Teroj from escaping offworld with the technology and explained that Teroj was an enemy of him and Flix, who had been trying to hurt their business for years. While Orka and Flix were grateful to Kaz for stopping Teroj, they still insisted that he clean up the mess. 
Orka was a male Chadra-Fan who ran the Office of Acquisitions on the Colossus with his partner Flix. Of the pair, it was Orka who took care of negotiations.
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Orka had brown fur, a gray beard and eyebrows, and black eyes.  He had a good sense for business and negotiations.  Orka was also known for his sense of humor. He once joked about his business, the Office of Acquisitions, stocking things that they did not have. 
Orka was a male Chadra-Fan who ran the Office of Acquisitions on the Colossus with his partner Flix. Of the pair, it was Orka who took care of negotiations. Orka and his partner Flix ran the Office of Acquisitions, a starship parts shop on the Colossus platform. Of the pair, it was Orka who took…