How The Pollution Patrol Can Fingerprint Hydrocarbons
Each day, smokestacks, tailpipes, and forest fires belch vast clouds of hydrocarbons into the atmosphere. Clean-air crusaders would love to cork these contaminants, but it isn't always easy to identify the source. Now, researchers at Massachusetts Institute of Technology think they can do that by studying microstructures in soot that should--in theory--identify each particle's history and source.
Scientists in California have used chemical "signatures" to link liquid carbon pollutants in Los Angeles smog to commercial barbecues. The MIT team is going after so-called elemental carbon particles that take much longer than liquids to break down. To obtain a "fingerprint," the team runs electron micrographs of soot through computers to generate 0uch details as spacing among the graphite layers. With a large enough database, says MIT chemist and team leader Adel F. Sarofim, such signatures could one day identify the specific carbons that, say, triggered a patient's lung cancer.