In 1972, on the basis of data on toxicity to fish and migrating birds (but not to humans), the U.S. Environmental Protection Agency banned virtually all uses of DDT.

FORBES: Beyond Copenhagen

Authorities said one test detected a pig-borne disease in the river called porcine circovirus, but that doesn't normally affect humans, according to the U.S. Centers for Disease Control and Prevention.

WSJ: Floating, Dead Pigs Repulse Shanghai

The leathery shelled mammals, which can be found in 10 states throughout the Southeastern U.S., are the only animals besides humans known to carry leprosy.

CNN: Armadillos linked to leprosy in humans

To even begin testing its Alzheimer's vaccine in humans, Elan will have to convince regulators in the U.S. and Europe that the new version is likely to be safe.

FORBES: Elan Readies New Assault On Alzheimer's