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Skip in Skip x Embed x Share CLOSE Scientists at the Scottish Marine Animal Stranding Scheme and the University of Aberdeen found extremely high levels of chemical pollution in a whale corpse. USA TODAY 
  
 Alex Costidis, right, coordinator with the Virginia Aquarium's Stranding Response team, and Kristy Phillips, necropsy manager, center, measure the length of a cut on a juvenile humpback whale before performing a necropsy at Craney Island in Portsmouth, Va. (Photo: The' N. Pham, The Virginian-Pilot via AP) 
  
 A killer whale found dead on the Scottish island of Tiree had one of the highest levels of PCB pollution ever recorded, scientists say. 
  
 Lulu, well known to researchers as one of the last surviving whales in the waters around Britain, died after becoming entangled in fishing rope in January 2016. The Scottish Marine Animal Stranding Scheme and the University of Aberdeen conducted an in-depth investigation of Lulu's carcass and were shocked by the findings. The headline on its website called the killer whale the "most contaminated on the planet." 
  
 Veterinary pathologist Andrew Brownlow said studies have shown that killer whale populations can have very high levels of polychlorinated biphenyl (PCB). 
  
 "The levels in this case are some of the highest we’ve ever seen," he said. "We know Lulu died from becoming entangled, but, given what is known about the toxic effects of PCBs, we have to consider (the contamination) could have been affecting her health and reproductive fitness." 
  
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 Analysis of Lulu’s blubber revealed PCB concentrations 100 times higher than the accepted toxicity threshold for marine mammals, the stranding scheme reports. High PCB levels are linked to poor health, impaired immune function, increased susceptibility to cancers and infertility. 
  
 Once PCBs get into the marine environment, they accumulate through food chains and are difficult if not impossible to remove, Brownlow said. 
  
 The investigation revealed that Lulu was at least 20 years old but apparently never reproduced, despite being much older than the average age for maturity in killer whales. Brownlow called Lulu’s apparent infertility an ominous warning and said it is "increasingly likely that this small group will eventually go extinct." Lulu lived in a pod of about eight whales. 
  
 PCBs were banned in the U.S. in 1979. From the 1920s until their ban, an estimated 1.5 billion pounds of PCBs were made for things such as microscope oils, electrical insulators, capacitors, and electric appliances such as television sets or refrigerators, the U.S. National Ocean Service says. PCBs were also sprayed on dirt roads to keep the dust down. Traces of PCBs have been detected in people and animals around the world. 
  
 Lulu’s skeleton is preserved at National Museums Scotland. The stranding scheme was set up in 1992 to analyze and report data for all marine mammals, marine turtle and basking shark stranding. 
  
 Read or Share this story: https://usat.ly/2pKSP3h ||||| Media playback is unsupported on your device Media caption Lulu was one of the most contaminated killer whales ever found (Image: John Bowler/RSPB Scotland) 
  
 One of the UK's last killer whales was contaminated with "shocking" levels of a toxic chemical, scientists say. 
  
 The animal, called Lulu, was found dead on the Isle of Tiree in Scotland last year after becoming entangled in fishing lines. 
  
 But tests now reveal her body contained among the highest levels of polychlorinated biphenyls, or PCBs, ever recorded. 
  
 The chemicals were banned from the 1970s but are still in the environment. 
  
 Researchers now fear that other animals in Lulu's pod also have similarly high levels of contamination. The group, which is found off the west coast of Scotland, is thought to consist of just eight animals. 
  
 Dr Andrew Brownlow, head of the Scottish Marine Animal Stranding Scheme and veterinary pathologist at Scotland's Rural College (SRUC), told BBC News that Lulu had "shocking levels of PCBs". 
  
 He said: "The levels of PCB contamination in Lulu were incredibly high, surprisingly so. They were 20 times higher than the safe level that we would expect for cetaceans to be able to manage. 
  
 "That puts her as one of the most contaminated animals on the planet in terms of PCB burden, and does raise serious questions for the long-term survivability of this group (of UK killer whales)." 
  
 Image copyright HWDT.org Image caption Lulu's level of PCBs are among the highest ever recorded 
  
 PCBs were used widely in industry during the last century. 
  
 The manmade chemicals are extremely stable, resistant to extreme temperatures and pressures, and have insulating properties. Because of this they were used in everything from plastics to paints and electrical equipment. 
  
 But after concerns about the toxicity to humans and animals was raised, a series of bans were put in place around the world from the 1970s onwards. 
  
 However the chemicals take a long time to break down and have lingered in the environment, particularly in landfill sites where they can leach into waterways and on into the sea. 
  
 They then build up in the marine food chain, which means top predators such as killer whales are particularly affected. Dolphins, porpoises are also susceptible. 
  
 Levels of PCBs are measured in milligrams per kilogram of lipids (fatty acids) in an animal's body. 
  
 Image copyright Nienke Van Geel/HWDT.org Image caption Today Lulu's pod has just eight animals and scientists now fear for their future 
  
 Dr Brownlow said: "The threshold where we think that there is some form of physiological effect caused by PCBs is around 20-40mg/kg stored within the tissues. 
  
 "Lulu had a level of PCBs of 957mg/kg - and this has put her as one of the most contaminated individuals we have ever looked at." 
  
 Scientists believe Lulu's age, estimated to be at least 20, may be one reason that the levels of PCBs were so high, because they had built up over the years. 
  
 The chemicals have a range of effects. There is evidence that they can impair the immune system. They also affect reproduction, preventing killer whales from bearing young. 
  
 "That's certainly what we found in the case of Lulu," explained Dr Brownlow. 
  
 "Having examined her ovaries, there was no evidence that she had ever been reproductively active or had ever had a calf." 
  
 The chemicals can also affect the brain. Scientists believe the contamination could have been implicated in Lulu's death. 
  
 "Killer whales are incredibly intelligent, they are very nimble, socially aware animals. [Lulu] would have spent most of her probably very long life existing around the waters of the West Coast. 
  
 "It is potentially plausible that there was some effect of the PCBs that was in some way debilitating her so she wasn't strong enough or even aware enough to deal with this entanglement (in fishing line). 
  
 "We very rarely see entanglement in killer whales - actually this is one of the first cases we have documented." 
  
 Image copyright Science Photo Library Image caption Landfill sites can contain PCB contaminated material 
  
 PCBs are a global problem, but a recent study revealed that European waters are a hotspot because of the level of the chemicals once used. 
  
 It is estimated that there is a million tonnes of PCB-contaminated material waiting to be disposed in Europe. 
  
 But getting rid of them is expensive and difficult - they need to be incinerated at more than 1,000C to be destroyed. 
  
 Prof Ian Boyd, chief scientific adviser at the Department of Environment, Food and Rural Affairs (Defra), said that the issue was very concerning but also complicated. 
  
 He said: "The records show PCBs have been declining in concentration in the marine environment, so the regulation we have in place is working. 
  
 "It's just they take a very long time to disappear. Overall I think we are going in the right direction, but it is going to take many more years to get to a point where they are going to disappear entirely." 
  
 He added: "Lulu was fairly old, so she will have accumulated [PCBs] over her lifetime and that's the reason she had such high levels. It's a legacy she'd carried from her early years, probably." 
  
 Media playback is unsupported on your device Media caption BBC Newsnight reported last year how PCBs can impact marine mammals 
  
 But some scientists think more should be done. Dr Paul Jepson from the Institute of Zoology at the Zoological Society of London said PCBs were not an intractable problem in Europe. 
  
 "PCB levels in the United States have slowly declined in humans and other biota such as fish for many years now, and the overall PCB mitigation is generally considered to be successful in the US. 
  
 "This is partly related to numerous US Environmental Protection Agency (EPA) Superfund sites, which the EPA is actively working to decontaminate. We urgently need a similar approach in Europe". 
  
 Killer whales - and other cetaceans - around the world are being hit by PCB contamination. But in the UK, with just eight remaining resident killer whales, the future looks very bleak. 
  
 Scientists have not seen any calves born in the 25 years they have been studying these animals, and it looks almost certain that they will eventually vanish from the UK's waters. 
  
 Lulu's skeleton is now stored at the National Museums Scotland collection centre, which has one of the largest whale collections in the world. 
  
 Principal curator of vertebrates' Dr Andrew Kitchener said the whales remains would be available for scientists to study. 
  
 "What these collections are here for is so we can use them for the benefit of living animals in the wild today and in the future. They do have a value for living populations." 
  
 Image caption Lulu's skeleton is now stored at the National Museums Scotland 
  
 Follow Rebecca on Twitter: @BBCMorelle ||||| Adult whale Lulu was one of UK’s last resident pod and had never produced a calf, probably because pollutants in her blubber had caused infertility 
  
 One of the highest concentrations of toxic pollutants ever recorded in a marine mammal has been revealed in a Scottish killer whale that died in 2016. 
  
 The adult whale, known as Lulu, was a member of the UK’s last resident pod and a postmortem also showed she had never produced a calf. The pollutants, called PCBs, are known to cause infertility and these latest findings add to strong evidence that the pod is doomed to extinction. 
  
 The level of PCBs found in Lulu’s blubber were extreme at 950mg/kg, more than 100 times the 9mg/kg limit above which damage to the health of marine mammals is known to occur. A 2016 analysis showed the average concentration for killer whales in the north-east Atlantic was about 150mg/kg. 
  
 'Extraordinary' levels of pollutants found in 10km deep Mariana trench Read more 
  
 Lulu died after becoming tangled in ropes used to haul up creels, the netted cages used to catch lobsters and crabs. But Andrew Brownlow, head of the Scottish Marine Animal Stranding Scheme, said: “Given what is known about the toxic effects of PCBs, we have to consider that such a high-pollutant burden could have been affecting her health and reproductive fitness.” 
  
 Brownlow, also a veterinary pathologist at Scotland’s Rural College, said: “Lulu’s apparent infertility is an ominous finding – with no new animals being born, it is now looking increasingly likely that this small group will eventually go extinct. One of the factors in this groups apparent failure to reproduce could be their high burden of organic pollutants.” 
  
 The examination of Lulu found she was at least 20 years old, well above the age of sexual maturity, which ranges from six to 10 years old. However, analysis of the ovaries shows she never bore a calf. The entire pod may have been left barren, as no calf has ever been seen in the 23 years the group have been monitored. 
  
 PCBs were used for decades in electrical equipment but finally banned in the 1980s after the full toxic impacts on people and wildlife were revealed. PCBs, which cause cancers and suppress the immune system, are especially harmful to top predators because they accumulate in fat up the food chain. Killer whales can live for many decades, meaning they can end up with very high levels of PCBs. 
  
 Tilikum and Granny are dead. Here’s why you should care about these killer whales | Patrick Barkham Read more 
  
 PCBs are extremely tough chemicals and do not break down in the environment. The decline in PCB levels in marine wildlife seen after the 1980s ban has now levelled off in some places, indicating that the toxic chemicals are still leaking into the oceans from inadequate waste storage sites. 
  
 “Once PCBs get into the marine environment, they are difficult if not impossible to remove,” said Brownlow. “There are still many PCB stockpiles in Europe, and it is absolutely essential that these toxic reserves do not reach the marine environment.” 
  
 Bottlenose dolphins in the north-east Atlantic have also shown both high PCB levels and low reproductive rates. Other PCBs hotspots around the world include the entire Mediterranean and the Black Sea, while specific populations suffering from PCB poisoning include belugas in Canada and polar bears across the Arctic. 
  
 In February, scientists discovered “extraordinary” amounts of PCBs had even reached the most remote and inaccessible place on the planet – the 10km deep Mariana trench in the Pacific Ocean. |||||
Output:
When Lulu died tangled in fishing nets in Scotland last year, she was one of the last killer whales in the UK. She was also "one of the most contaminated animals on the planet," Dr. Andrew Brownlow tells the BBC. Brownlow says Lulu's body contained "shocking levels of PCBs." Researchers found 957 milligrams of PCBs per kilogram in the killer whale; it's believed the toxic chemical starts causing health problems for marine mammals at just 9 mg/kg, according to the Guardian. The average concentration of PCBs in killer whales in the northeast Atlantic is 150 mg/kg. PCBs can hurt the immune system and hamper reproduction, and the latter effect has scientists worried for the future of killer whales in the UK. Despite being at least 20 years old, Lulu doesn't appear to have ever been "reproductively active." If the rest of Lulu's eight-whale pod has similar levels of PCB contamination, it's "increasingly likely" it will go extinct, Brownlow tells USA Today. Scientists haven't seen any killer whale calves born in the waters around the UK in the past 25 years. PCBs were outlawed in the 1970s but don't break down in nature and may still be leaking into the environment from waste storage sites. They work their way up through the food chain stored in the fat of animals; and killer whales are near the top of that chain.