
Photo: ALAN JAMIESON / NEWCASTLE UNIVERSITY
The bottom of the Mariana Trench, in the western Pacific Ocean, is the deepest point in any ocean of the world. At its deepest, the bottom is over 36,000 feet below the surface. In comparison, Mount Everest is 29,000 above sea level, or over a mile shorter than the trench is deep.
Researchers studying animals that live in these great depths have made several disturbing discoveries. Alan Jamieson, a marine biologist at Newcastle University, has been studying amphipods—scavenger relatives of crabs and shrimp that dwell in the deepest abyss. A few years ago, he tested these tiny creatures for pollutants and found high concentrations of toxic polychlorinated biphenyls, or PCBs. PCBs have been banned for decades but persist in nature. Recently, Jamieson and his team started testing the amphipods for plastics.