Campus News

As thirdhand smoke risks grow clearer, researchers turn to policy

June 20, 2017
Jonathan Samet

The harmful effects of smoking don’t end with a cigarette, researchers say

On World No Tobacco Day, May 31, researchers and stakeholders met at USC to size up the dangers of “thirdhand smoke,” the toxic residue from cigarette smoke that settles on furniture, clothing, hair and other surfaces.

Scientists discovered it contains deadly, cancer-causing compounds—such as cyanide and arsenic—that can react with an environment to create secondary, more dangerous, toxins.

Many contaminants remain in dust and on surfaces, and can linger for months—even years. And unlike secondhand smoke exposure, thirdhand smoke isn’t limited to inhalation; people may also unknowingly ingest it or absorb it through their skin.

Some more affected than others

Infants and small children, as well as pets, are more likely to be exposed due to their tendency to spend time on surfaces like carpets and blankets, and are prone to placing exposed items in their mouths.

In addition, thirdhand smoke could disproportionately affect low-income earners who cannot afford new cars and homes that haven’t been smoked in.

Science underway

Since 2011, the Thirdhand Smoke Consortium, funded by the University of California Tobacco-Related Disease Research Program, has been pioneering research to understand what constitutes thirdhand smoke, and how it gets generated. Scientists have tested smoking chambers, hotels, cars, hospitals, mice and more.

Tasked with translating these findings into protective laws and practices, USC gathered biologists, chemists, lawyers, health care workers and housing professionals at the May 31 workshop to discuss next steps.

“The goal is to try and understand where we are with the science and what that evidence will support in terms of policy,” said Jonathan Samet, Flora L. Thornton Chair of the Department of Population and Public Health Sciences and the consortium’s USC principal investigator. “We have already dealt with many indoor pollutants—asbestos, radon, lead, for example. The question is, what are the policy approaches that can be used for thirdhand smoke?”

One study from consortium researchers at UC Riverside helped pass California legislation in 2014 to prohibit smoking at all times in home daycare centers and areas where children are present.

To build upon that momentum more work lies ahead, Samet said. “Tobacco is the leading preventable cause of death—and thirdhand smoke is yet another part of the problem that policymakers, consumers and the public should know about.” 

— By Larissa Puro