Um... you first.

TUCSON, Ariz. - Recent tests have shown that a brain-eating amoeba is in Tucson's water supply, but experts say the microscopic bug doesn't pose any health risks.

Tucson Water chlorinates its well water before distribution, killing the amoeba known as Naegleria fowleri before the water hits taps. But the amoeba's presence in our underground water source — probably as a result of biodegradable oil used in pumps — is a surprise to some researchers. The amoeba is usually found in surface water such as rivers and lakes.

"The organism is everywhere," said Charles Gerba, a microbiology professor with the University of Arizona's Department of Soil, Water and Environmental Science. "It feeds on bacteria."

Naegleria fowleri made headlines recently when it killed a 14-year-old boy who had gone swimming in Lake Havasu last month.

The amoebas enter the body through the nose and travel to the brain, where they feed until the person dies. The only way to get infected is to snort water. A person can drink water that has Naegleria fowleri and never be infected.

The amoeba lives in soil and is often present in warm bodies of water, particularly hot springs and lakes. Pools, if not chlorinated properly, can become homes to the microbes Tucson Water joined Maricopa County cities in a study of well water in 2005 to determine the amoeba's presence in drinking water and develop treatment to eliminate any potential health risks.

The moral of this story is don't make your siblings snort their drinks from laughing at the dinner table. Your mom will freak out....