A polar bear near Kaktovik, Alaska. New research reveals how polar bears keep ice off their fur. Alan Wilson via Wikimedia Commons under CC BY-SA 3.0Polar bears dont have to worry about skipping a wash day. The sebum, or natural oil, on the mammals fur helps them survive the harsh Arctic weather by making it hard for ice to stick to them, according to a study published Wednesday in the journal Science Advances.Senior author Bodil Holst, a physicist at the University of Bergen in Norway, was inspired to investigate polar bear fur after watching a TV quiz program, she tells Michael Le Page at New Scientist. She realized that she had never seen a polar bear covered in ice in any wildlife documentaries, even after they emerged from a dive in below-freezing water.And then I thought, well, how come freezing is not a problem? How come you dont get accumulation of ice on the fur under these circumstances? says Holst to New Scientist.To answer those questions, Holst gathered an international team of researchers. The group compared ice resistance in samples of four materials: washed and unwashed polar bear fur, human hair and hair-based ski equipment coated in chemicals called fluorocarbons. They tested the materials by measuring how much force was required to move an ice block off of each one, writes Sciences Alexa Robles-Gil.Julian Carolan, the studys lead author and a chemist at Trinity College Dublin, even used his own hair for the research. It wasnt that pleasant to do, he tells the Washington Posts Dino Grandoni. I had to let my hair get very greasy over a week, which did not look very good. I then shaved it all off as close as I could to the scalp, which was tough on account of the greasiness. This also left me with a bald head in the cold month of January last year.For their efforts, the scientists found that ice has a much harder time sticking to unwashed, greasy polar bear hair than to oily human hair. When the polar bear fur was washed, it performed more like human hair, pointing to the sebum as the key to the anti-ice effect.They then performed a chemical analysis of the polar bear sebum and identified cholesterol, diacylglycerols and fatty acids as its primary components. Additionally, the bears sebum did not contain squalene, a fatty oil found in the hair of humans, sea otters and many aquatic mammals, suggesting this lack could help with ice resistance, per a statement from Trinity College Dublin.The study confirms what people who work closely with polar bears have long known, as Geoff York, a biologist with Polar Bears International who was not involved in the research, tells the Washington Post. When we get them on the ground, and theyre safely sedated, theyre amazingly dry.These new findings also reinforce Indigenous knowledge about the Arctic-dwelling bears, per the paper. Inuit people have taken advantage of the sebums properties, even affixing shoe-like patches of polar bear fur to the bottom of stools to prevent them from sticking to the ice.Understanding how polar bears stay warm and dry in the Arctic could help scientists develop alternatives to PFAS-laden anti-ice repellants. PFAS, also known as forever chemicals because of how long they persist in the environment, are often used to make non-stick and water-resistant materials. The researchers say engineers could use the ingredients found in polar bear sebum to create safer products.If we do it in the right way, we have a chance of making them environmentally friendly, says Holst to the Washington Post. That is certainly the inspiration here.Get the latest stories in your inbox every weekday.Filed Under: Animals, Arctic, Bears, biomimicry, Chemistry, Environment, Innovations, Mammals, New Research