Lab tests showed the salmonella was caused by a fermentation of whatever was in the vials. Authorities said two out of a "number of vials" contained salmonella.
No link was cited between the incident and the spate of anthrax letter attacks gripping the United States.
"This has nothing to do with the other mailings" that have spread anthrax in Washington, New York, New Jersey and Florida, said Secret Service spokesman Jim Mackin.
Traveling in Rome with his daughter, the former president said the terror attacks represented the dark side of globalization.
Salmonella, a bacteria which can prove deadly for young children and people with weakened immune systems, is usually found in eggs, meat and poultry.
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