The Dangers of Thirdhand Smoke

You’ve probably heard of secondhand smoke—the smoke that’s exhaled by someone indulging in a tobacco product, specifically cigarettes or cigars. Also called passive or secondary smoke, secondhand smoke increases the risk for many diseases. Exposure to nonsmokers increases their lung cancer risk by about 20% and is thought to cause approximately 53,800 deaths annually in the United States.

But there’s also thirdhand smoke—the persistent residue generated from aged secondhand smoke that adheres to indoor dust and surfaces and reemits into the air, which is also a concern regarding public health, according to a publication by Public Health Rep. It’s estimated that 5% to 60% of the harm assumed to be caused by secondhand smoke might instead be the fault of thirdhand smoke.

In a Mayo Clinic article, Dr. J. Taylor Hays discussed how thirdhand smoke builds up on surfaces over time and can become embedded in soft surfaces, such as furniture, drapes, bedding, and carpets. It also settles as dust-like particles on hard surfaces, such as walls and floors.

Unfortunately, removing it, he said, is not as simple as just “airing out” a room. Furthermore, traditional household cleaning often cannot remove thirdhand smoke effectively from many surfaces.

As difficult as it might be, the website thridhandsmoke.org offers several ways to attempt to remove thirdhand smoke, including the following:

• Frequent vacuuming with a HEPA filter and regular cleaning of hard surfaces with acidic and alkaline cleaning solutions
• Machine washing of fabrics such as blankets and pillows
• Using a dishwasher (several times if necessary) for plates, pots, and cutlery
• In the case of contaminated walls, using trisodium phosphate (TSP) to deal with persistent thirdhand smoke residue, followed by special paint primers.

Watch out for hidden surfaces such as HVAC ducts, undersides of tables, insides of cabinets, and backsides of bookcases, as well as any covered wall spaces. Consider disposing and replacing any polluted items that cannot be cleaned.

But the website also cautions that unless the underlying reservoirs of thirdhand smoke are completely removed, it will be re-emitted from these reservoirs and continue to pollute household surfaces and dust. This includes walls that have been primed and repainted. Sadly, attempts to completely remove thirdhand smoke can be a losing battle.

So, the most effective way of dealing with thirdhand smoke is to never introduce it into the environment in the first place. All smoking of tobacco should take place outside of buildings to prevent the dangerous and often permanent contamination caused by thirdhand smoke. If you manage a building or facility, a smoke-free policy is your best defense against the costly repairs and replacements due to thirdhand smoke damage.