Through a series of scientific tests at a popular Chicago bar/restaurant, Dr. Alan Hirsch, founder of the Smell & Taste Treatment and Research Foundation in Chicago, discovered that while the odor of cigarette smoke is gone, equally offensive odors that were previously hidden have surfaced.

The tests showed that bar patrons were a major cause of the stink. Sweat was one of the top odor contributors to the "bar funk" and in addition to armpit odor, smells from patrons' backs, heads and abdomens were also potent.

While these tests were conducted in only one bar, the results could shed light on why other smoke-free establishments are also experiencing "bar funk," Hirsch said.

Using scientific odor-gauging instruments, Hirsch performed an "ambient odor concentration" test to quantify how bad the smoke-free bar smelled.

Based on ambient odor intensity levels -- 60 being most smelly and zero being least smelly -- a smoke-free bar was found to have a 50, compared to a swine production site at 60, an animal rescue facility at 30, a men's room at 15, or industrial site at seven.