A collection of over 10 million shells housed at Philadelphia’s Academy of Natural Sciences is being used by scientists to better understand historical levels of environmental contamination in the Gulf of Mexico.  The collection, dating back to 1812, includes more than 100 oyster shells collected from the Gulf between 1887 and 1960.

Shells can serve as a record of water pollution, as mollusks incorporate ingested contaminants, such as hydrocarbons, polychlorinated biphenyls, and heavy metals, into their shells.  Scientists are currently comparing the composition of shells in the museum with oysters collected after the BP oil spill.  This analysis should reveal if water pollution levels have changed throughout the region in the wake of the oil spill.

“You never know what these things will be useful for,” said Peter Roopnarine, the leader of the ongoing study, whose first results are expected by September. “Each individual shell is going to give us a record back in time.”