SAN DIEGO, Dec. 30 (UPI) -- Smoking cigarettes and exposure to secondhand smoke are well known threats to health. Particles contained in cigarette smoke that settle on surfaces, known as thirdhand smoke, also pose a significant health danger.
Although the number of smokers in the United States has reached an all-time low, researchers say a residual threat still lurks that people cannot see or smell.
Nicotine and other cigarette-borne particles can be found in of the homes of people who quit years after the last time they light up. Chronic exposure to thirdhand smoke often goes undetected because people don't know it exists, according to researchers at San Diego State University.
"We were really surprised by how persistent the contamination is in the home, even months after people have stopped smoking in it," said Penelope Quintana, an environmental health scientist at San Diego State University, in a press release.
The TSRC conducted a series of studies between 2011 and 2014 on thirdhand smoke generation, characterization, evolution, and its potential effects on health.
The studies reported particles can be found on every surface from counters and drywall to couches and carpet, and revealed a particular danger for children because of their propensity to touch any surface within arms' reach and often end up with their hands in their mouths or noses.
"Cigarette smoke is known to contain thousands of chemicals, and these chemicals get deposited onto surfaces," said Eunha Hoh, an environmental chemist at San Diego State University. "A great many of them are known to be toxic and carcinogenic. The levels of these chemicals may be quite low in thirdhand smoke residue, but they are dangerous when you have chronic exposure."
Researchers at San Diego State, one of several universities involved with thirdhand smoke research, plan to recruit 200 low-income homes during the next three years as part of a study to find an effective, affordable method of cleaning it up. The methods to be tested range from dusting to professional deep cleaning, with the houses analyzed for levels of remaining particles along the way, researchers said.
"There are no real known solutions for cleaning up thirdhand smoke," Hoh said. "We need to find a way to get rid of it.