"The challenge is that the chemical reactions these bacteria use are very unusual---not the standard chemical reactions that chemists usually think about," said Marsh. "It turns out that the solution to metabolizing these very inert compounds is to harness the reactive chemistry of free radicals. To a chemist it's an elegant solution to a difficult problem---even if we still don't really understand how the enzymes that catalyze these reactions work, for everyone else it could mean less pollution."