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Edible Motor Oil


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Duane Johnson may have developed the world's cleanest motor oil. He is so sure of the safety of his product that he submits it to an unusual test: he eats it. "When I go to meetings and have an engine running on this stuff, I'll pull the dipstick out and lick it." Petroleum-based motor oils cause a significant amount of the pollution a car releases, says Johnson, an agronomist at Colorado State University. His motor oil, made from canola and other vegetable oils, not only produces no air pollution of its own but cuts overall engine emissions by up to 30 percent.

Johnson's motor oil is easy to make. He heats canola seeds and then crushes them to release the oil. He then mixes in small amounts of other oils, including sunflower, soybean, and castor oil to get the right consistency. "This is tabletop technology," he says. "We use a paint mixer to mix it and it's ready to go."

This simple processing, says Johnson, is what makes the oil work so cleanly. Previous tries at using vegetable oils in cars started with refined oils with all the natural antioxidants removed. Without them, the hot oil turns into a stringy goop after about 12 hours in an engine. "We didn't strip out the natural antioxidants," says Johnson, "so a normal oil-change period of 4,000 miles is not a problem."

Johnson has made preliminary tests of his oil in several car models. He first runs regular oil through the cars and does a standard emissions test, then repeats the process with canola oil. In his tests a 1971 Volkswagen's emissions were cut by 30 percent; a 1970 Mustang's by 15 percent. Thanks to clean-air laws, more recent models are less polluting, says Johnson, but canola oil still reduces hydrocarbon emissions from brand-new vehicles. "Vegetable oils have always been better lubricants than petroleum," says Johnson. "They reduce the friction inside the engine so it works more efficiently. You get less pollution from the gas as well as from the oil."

Petroleum motor oils are hazardous waste, costly to dispose of properly. Canola oil, on the other hand, biodegrades quickly and won't pollute groundwater, so it can be disposed of in a regular landfill. "It has about the same toxicity as maple syrup," says Johnson. He now sells the oil for $1.50 a quartoabout the same price as regular motor oil. The city of Fort Collins, Colorado, is already trying out the oil in one of its official vehicles. And the Wisconsin State fleet might soon have 300 of its cars running on the stuff. "They'll test it for six months," says Johnson. "If it worksowhich it willothey will mandate it for all their vehicles."

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