Researchers estimate that mercury emissions in the atmosphere have quadrupled since the Industrial Revolution. The heavy metal, generated by burning fossil fuels and the disposal of industrial and medical waste, has become so persistent in aquatic environments that the U.S. Food and Drug Administration suggests about a half dozen species of fish are so mercury-contaminated that people should avoid consuming them. Researchers have been working for many years to develop systems for removing mercury from water. But a team at Drexel University might have found just the right material to efficiently catch the evasive quicksilver—even at low levels—and clean up contaminated bodies of water.