Chemicals contaminate virtually every stream in the Lower 48. The graph above shows that almost 80 percent of waterways tested between 1992 and 1998 are awash with five or more dangerous substances, from pesticides to PCBs; more than 90 percent contain at least three contaminants.
These findings are part of The State of the Nation’s Ecosystems, issued by the Heinz Center for Science, Economics, and the Environment. The report also reveals that three-fourths of these streams are so polluted they may be toxic to fish, and 13 percent contain enough chemicals to harm humans.
