Alien invaders to Lake Erie are helping some harmful chemicals move from lake sediment to sport fish that humans eat.
For the past 20 years, aliens have been invading Lake Erie. but they haven't come by spaceship - they've hitchhiked a ride into the lake in the ballast water of ships from across the Atlantic.
Zebra mussels, a non-native species first found in Lake Erie in the mid-1980s, and their cousins the quagga mussels, have been held responsible for numerous offenses including competition for food needed by native species and clogging up pipelines. They have also, ironically, helped to improve lake water quality by feeding on the excessive nutrients that once poured into the lake with agricultural and industrial runoff.
But now, OSU researchers say, these mussels are part of another problem.
Gene Kim, a graduate student in Ohio State University's aquatic ecology lab, says that two non-native species - zebra mussels and round goby fish - have helped to form a new food chain within the lake - a chain that can connect harmful chemicals in Lake Erie soils to humans.
Roy Stein, a professor in osu's aquatic ecology laboratory, says that PCB's and other contaminants, once held captive in the soil at the bottom of Lake Erie, now have a pathway up the food chain.