Air pollution is a serious problem in many parts of the world, but just how serious is often not clear because it costs a lot of money to get accurate readings.
Fortunately, Larry St. Clair of Brigham Young University in Utah may have found a quicker, cheaper way to monitor air quality: lichens.
Because lichens mop up pollutants like sponges, St. Clair decided to see if they did so in a manner that reliably reflects the level of contaminants in their surroundings. His team harvested lichens from sites in four states—Arizona, New Mexico, Wyoming, and Colorado—that are plagued by copper pollution. The researchers then assayed concentrations of copper in the lichens and compared the results with those acquired using mechanical monitoring devices.
As pollution detectors, the lichens were as accurate as the best equipment available. St. Clair says the lowly lichen could revolutionize biomonitoring. He envisions transplanting the organisms to keep watch over highly polluted areas all over the world: "There's no reason we can't extend the predictability of the system to some of the other pretty nasty things that are being put into the air."