Knox News: Scientists cannot find traces of oil in the deep water of the Gulf of Mexico three years after the nations worst offshore spill, but residual toxins are still in the sediment along the coastal marshes, according to scientists at the University of Tennessee who have studied the effects of the spill. Bacteria in the Gulf was already adapted to consuming oil that naturally leaks from the ground into the water there, said Terry Hazen, a Governors Chair for Environmental Biotechnology at UT and Oak...