Original: Dead zones exist off the East Coast of the United States in the Chesapeake Bay , in the Scandinavian strait Kattegat , the Black Sea ( which may have been anoxic in its deepest levels for millennia , however ) , in the northern Adriatic as well as a dead zone off the coast of Louisiana .
Simplified: ` Dead zones ' exist off the East Coast of the United States in the Chesapeake Bay , in the Scandinavian strait Kattegat , the Black Sea , in the northern Adriatic and off the coast of Louisiana .