Being exposed to secondhand smoke in an enclosed space such as a car has a direct impact on the brain and may increase cravings among smokers, a new study suggests. The authors say that this exposure in children might increase the chance they will become smokers in their teen years.
The study included 24 young adults (11 smokers and 13 nonsmokers). They underwent two positron emission tomography sessions, during which they sat in the passenger’s seat of a car for one hour and were either exposed to moderate secondhand smoke or had no secondhand smoke exposure.
Science Daily reports that in both smokers and nonsmokers, being exposed to secondhand smoke for one hour resulted in substantial binding of nicotine to brain receptors that are normally targeted by direct exposure to tobacco smoke. The smokers had an average 23 percent increase in cigarette craving after being exposed to the smoke.
The researchers, writing in the Archives of General Psychiatry, say that the findings suggest that this secondhand smoke exposure “delivers a priming dose of nicotine to the brain that contributes to continued cigarette use in smokers.”
A press release issued by the U.S. National Institute on Drug Abuse, which funded the study, noted that previous research has shown that exposure to secondhand smoke increases the chance that children will become teenage smokers and makes it harder for adults to quit smoking.
The researchers note that recent laws have banned exposure of children to secondhand smoke in cars in four states. “Results of this study strongly support these public policy recommendations,” they write.