(NBC) - For years, health organizations have cited the health risks associated with cigarettes and second-hand smoke, but did you know that cigarettes can still be dangerous even when there's no smoke?
Cigarette butts are tossed out of car windows, flicked onto sidewalks and stuffed into the sand. These butts, and other forms of tobacco debris, are the most common form of litter in the world.
Dr. Cheryl Healton is president of the American Legacy Foundation, a non-profit committed to reducing tobacco use. Healton said cigarette butts are filled with toxins - nicotine and tar.
"It degrades into little fluffy pieces of toxins," Healton said. "Biodegrading something that's composed of toxins really just helps introduce the toxins more widely into the environment."
In a 2009 lab study, researchers at San Diego State University soaked one cigarette butt in less than a gallon of water for 24 hours, then added minnows to the tank. About half the fish were dead within days.