Every so often in this anti-cancer blog, the science propels us to deviate from our nutrition and cancer focus and report to you on compelling research.  

Remember secondhand smoke—the kind you get from nearby smokers? Now it turns out that thirdhand smoke, which clings to surfaces long after the source has departed, is also deadly—maybe even more so.

Thirdhand smoke triggers significant genetic damage in human cells, according to a new study from a group of US researchers.  It gets into dust, clothing and carpets and causes damage to DNA, including breaks in strands, that can lead to genetic mutations and cancer.

According to a geneticist I recently heard, mutagenic changes in one generation can now be traced several generations down the line.

Shame on you, Big Tobacco.  You killed my mother at the age of 60 (pictured here) and her parents at a similar tender age.  Did you also cause my cancer and the break on my daughter’s 22nd chromosome?  How long did you carefully guard your secret that cigarettes maim and kill?

Growing up in North Carolina in the 50s and 60s, we’d come home from school to a haze of leftover smoke.  Everybody smoked.  It was cheap and fashionable. Nobody knew any better.

Several decades later, as I scurried back and forth from the hospital in which my mother was dying of lung cancer and the ICU in which my newborn daughter, on a respirator after open heart surgery, was struggling to live, I was struck by the sign:  Duke University’s pediatric intensive care unit, funded by Big Tobacco.  

Chronic exposure, it turns out, may be even worse than secondhand exposure.  The researchers put paper strips in smoking chambers and exposed the acute samples to five cigarettes smoked in about 20 minutes– the chronic samples to leftover smoke for 258 hours over 196 days, ventilated for many hours.

They found higher concentrations of many chemical compounds and more DNA damage in the samples exposed to chronic thirdhand smoke.  In fact, one of the significant carcinogens in thirdhand smoke was not even found in the secondhand smoke. This research suggests that the residues become more toxic over time, the scientists say.

Chemical compounds in cigarette smoke stick to surfaces and are particularly difficult to eradicate; vacuuming, wiping and ventilating don’t work, they say. The best solution: Change the materials, get rid of the old carpet, even repaint (but beware the paint fumes, of course.)

To read more about this anti-cancer outrage, the first study to show that thirdhand smoke causes genetic damage in humans, click here.