Workers and customers at New York City hookah bars are inhaling hazardous levels of second-hand smoke, according to Bouncer Chronicles. A New York University (NYU) study tested 10 hookah workers when their shifts ended. The reports found elevated levels of toxins as well as inflammation that could be linked to lung and heart diseases. Hookah bars are usually protected from the city's clean-indoor air rules.

Terry Gordon, a NYU professor, said this is the first study to link these bars with damaging effects to their workers.