A Messy Mix Of Biodiesel

By John Carey

His experiment aimed to find out if biofuel spills are harmful to sea life. But marine chemist Christopher Reddy of the Woods Hole Oceanographic Institution in Massachusetts discovered something else: Some of the biodiesel he’d bought to conduct his tests didn’t contain the advertised amount of processed animal or vegetable oils. His samples of B20 biodiesel—a blend used by many, including the military—were labeled as 20% diesel fuel made from biological sources and 80% regular diesel fuel. But “they were so dramatically different, I knew something was wrong,” he says. The biodiesel portion of his B20 blends, he found, actually ranged from 10% to 74%. Such inaccuracies are risky. Blends with too much biodiesel can damage engines. The National Biodiesel Board acknowledges the problem but says the industry has been taking steps to fix it—reducing the amount of biodiesel blends nationwide that don’t meet specs from 50% in 2005 to 10% today. As for Reddy’s original study, he found a biodiesel spill is much less harmful than a regular oil spill. “Microbes eat it really fast,” he explains.