A team of researchers at Dartmouth College created a breakthrough device that can immediately detect the presence of secondhand cigarette smoke, and even third-hand smoke.

Secondhand smoke detector (© Eli Burakian)
The device, described in a paper in the journal Nicotine and Tobacco Research, is smaller and lighter than a cellphone. It uses polymer films to collect and measure nicotine in the air; a sensor chip then records the data on an SD memory card.
“We have developed the first ever tobacco smoke sensor that is sufficiently sensitive to measure secondhand smoke and record its presence in real time,” explained co-author Prof Joseph BelBruno. “This is a leap forward in secondhand smoke exposure detection technology and can be considered the first step in reducing the risk of health effects.”
The U.S. Environmental Protection Agency says children are especially vulnerable to environmental tobacco smoke. While many parents try not to smoke around their children, going to a different room or smoking out on the porch may not be going far enough. Now, for the first time, there is a prototype sensor that will let the parent see whether or not their precautions make a difference.
“The intent of the project isn’t to make them stop smoking, but it is to make them stop exposing their children to smoke. On the other hand, if they are worried about their children, demonstrating these exposures may be an incentive for them to stop,” Prof BelBruno said.
Secondhand smoke comes from the burning end of a cigarette or from smoke exhaled by the smoker. Third-hand smoke, also a potential health hazard, is nicotine residue that remains on clothing, furniture, car seats, and other material after the air has cleared.
While the current device is a patent-pending prototype, the researchers foresee the eventual availability of an affordable consumer version that will incorporate a computer processor, reusable polymer films, and a rechargeable battery. It may even incorporate an LED panel to provide instantaneous readouts.
In addition to its uses in safeguarding childhood health, there are commercial applications for these unique detectors. Installed in rental cars, hotel rooms, and restaurants, this device could help enforce owner and operator smoking bans through an alert system, much like existing, ceiling-mounted smoke detectors.
Before the secondhand smoke project, the scientists had been working on sensor development for problem molecules such as heavy metals and other toxins in the water and the air. Given the hundreds of compounds in cigarette smoke, they began with a plan for a multi-component sensor but found this approach unnecessarily complex. The sensor they came up with detects cigarette smoke alone, simply and efficiently.
______
Bibliographic information: Yuan Liu et al. Detection of secondhand cigarette smoke via nicotine using conductive polymer films. Nicotine Tob Res, first published online March 11, 2013; doi: 10.1093/ntr/ntt007