Hey, don't go insulting petri dishes. As far as this doctor knows, a petri dish has never had a namesake disease. The hot tub, though, has hot tub folliculitis. HFC occurs when a malicious microorganism called Pseudomonas aeruginosa, which thrives in warm water, fouls up hair follicles and other vulnerable areas. Think rashes, pustules, and boils on, or in, the skin, eyes, ears, and lungs. A Texas A&M University study found that 56 percent of 43 whirlpools tested were swimming with the bitchy little pathogens. What's more, HFC hardly accounts for all the hell caused by a relaxing soak. Since airborne spores thrive in steam, Legionnaire's disease has afflicted hundreds of hot-tubbers, and killed seven in the last five years. On a brighter note, a mercy killing is also available from these fetid cauldrons of death: The industrial-strength suction from hot tub drains "can entangle a person's hair or body parts," says the U.S. Consumer Product Safety Commission. "Children and adults alike have been held to the bottom...and drowned." Have a nice dip.