Smoking Home & Cars

You know that smoking and secondhand smoke (smoke from a burning cigarette and exhaled by a smoker) are unhealthy. But another danger may surprise you — thirdhand smoke, which is residue that lingers long after you empty the ash trays.

Thirdhand smoke is residual — or leftover — nicotine and other chemicals that remain on clothing and surfaces after someone smokes in the area. Dangerous residue from tobacco smoke sticks to carpets, walls and other surfaces after the smoke clears.

Researchers believe these lingering chemicals can harm your body just like smoking and secondhand smoke can.

Researchers are investigating thirdhand smoke as they seek to understand some puzzling lung cancer cases.

“There’s been an increased interest recently because we are seeing more lung cancer cases that are not related directly to firsthand or secondhand smoking,” Dr. Choi says. “So we’re looking at other causes for cancer aside from direct exposure.”