What is Third-Hand Smoke? Is it Dangerous?
Smoke smells take a long time to dissipate. I have bought wooden furniture, clothing, an SUV, and a couch from smokers (with months to years between these purchases) and I remember thinking at the time, this is not too bad. This thought probably occurred after my sense of smell had already been deadened in the smoker’s home. Then, I put the item in my car (or drove the SUV home) and thought, Ok, I just need to air it out well. Then, I got to my unscented home and realized WOW! It was bad. What do I need to do now? Throw it out? I had to give the couch away, but other things were salvageable.
For someone who is conditioned to recycle and reuse, throwing an item away may seem like an extreme measure, but you should consider what is making the smell. It’s called third-hand smoke. Smoke released in a room or car contains nicotine toxic chemicals like nicotine that clings to walls, clothing, upholstery and other surfaces (mayoclinic.org). Results of a study published in 2010 found that when this nicotine reacts with nitrous acid in the air, it forms carcinogens, which are compounds that can cause cancer. (health.clevelandclinic.org) It’s not clear how much damage third-hand smoke does to our bodies, but it can cause DNA breaks and is thought to be more dangerous to children. Clearing third-hand smoke is not as easy as wiping down and airing out the item, because the “off-gassing” may occur over years.
Here are some examples of how to clean smoke-contaminated items:
Ozone generators: ozone is a proven way to remove smoke from surfaces. For years, hotels and auto detailers have relied on ozone generators to remove smoke from hotel rooms and cars quickly (in a matter of hours). Because there are three oxygen atoms in an ozone molecule, it is unstable, and the extra oxygen molecule will break away and bind to other molecules, converting them to safer, less odorous molecules. In the high concentrations that are needed to remove smells, the EPA warns that ozone can cause damage to our health, plants, rubber, electrical wire coatings, fabrics, and the dyes and pigments in some artwork. Therefore, it’s not safe to breathe and should only be used for 2-4 hours and then the space sealed off for some time before ventilation (up to several days for maximum effect). (washingtonpost.com)
To get the most effectiveness out of the ozone treatment, all surfaces in the room or car should be thoroughly cleaned first, then you can use an ozone generator like this one to finish the smoke removal in small spaces. The end of this video describes the safe use of the ozone generator in a car.
Vehicles: Like couches and furniture, seat cushions don’t give up the smell very easily. Here is an excellent video that recommends Citrol 266 used in a specific way to remove smoke permanently from fabric (NOT for use on plastics).
It’s important to realize that when the car ventilation is running, smoke can pollute the cabin air filter. It’s best to replace the filter with a new one.
If the item is small and relatively inexpensive, you could consider tossing it and accepting the loss. However, whole homes can be contaminated with third-hand smoke, and although costly, rehabilitation is quite possible.
- Carpeting and drapery is sometimes successfully cleaned with Citrol 266 at a 10:1 dilution (see video for application tips–don’t use on wood or plastics), or by using an ozone generator. If not, these soft items should be removed and discarded because the chemicals from the smoke have penetrated to the padding, which is not accessible.
- If removing and replacing the drywall is not an option, walls can be painted to seal in the odor by carefully cleaning and priming them before painting. This article gives advice from a professional painter and while the cleaning solutions and primer he uses are not non-toxic, the cleaning solution is washed away and the primer (BIN) solvent completely evaporates and can be covered by any low-VOC paint.
- Ventilation ducts may have to be replaced if they are internally insulated.
- If you can clean the flooring with water and cleaner, it may take several rinses to get all of the nicotine and residual chemicals from the surface. Vinegar can be helpful in this process. If the flooring cannot be cleaned by water, such as hardwoods, you can seal it with a number of safer products (see this article). Professional remediation is possible but may require chemical stripping or sanding, which can release a lot of PM and VOCs. As a last resort, you may need to budget flooring replacement!