Even as COVID-19 restrictions are being lifted all over the US, and we spend more time away from home, thirdhand smoke remains an important source of air pollution in our homes. Dr. Noelia Ramírez González, of the Institute of Health Research Pere Virgili and the Universitat Rovira i Virgili, in Tarragona, Spain, encourages awareness of the risk of thirdhand smoke in the wake of the pandemic.
June 16, 2021
During strict pandemic restrictions when many of us spent more time at home indoors, we were reminded of the importance of air quality inside our homes. It is well known that secondhand smoke is harmful to people, and many policies are in place to protect us from exposure in public spaces, and we can take personal action to reduce exposure to secondhand smoke in our homes. However, there is an additional tobacco risk that is less well known: thirdhand smoke, the toxic chemicals left behind after smoking stops.
Dr. Noelia Ramírez González, of the Institute of Health Research Pere Virgili and the Universitat Rovira i Virgili, in Tarragona, Spain, makes the case that thirdhand smoke should be considered to the same extent as secondhand smoke.
“Firstly, the chemicals in thirdhand smoke build up over time on indoor surfaces, stay for months after the last cigarette was smoked, and cannot be removed by cleaning or ventilation. This means that tobacco smoke exposure lasts far longer than thought with secondhand smoke. Secondly, thirdhand smoke which settles on surfaces can re-enter the air as gas, or even react with other things in the air to create other toxic substance, some that are even more dangerous than the original chemicals, such as cancer-causing tobacco-specific nitrosamines (TSNAs). The third reason, which is more important now than ever before, is that thirdhand smoke is found in many places, even those with strict smoking bans. This means that household smoking bans are a good start, but not enough to completely remove the risk. Finally, the main way that people are exposed to thirdhand smoke is through skin contact and ingestion. This means that young children are at especially high risk because of their hand-to-mouth habits.”
While there is a great deal of information about children’s exposure to secondhand smoke, research rarely includes exposure to thirdhand smoke. Since secondhand smoke is the precursor to thirdhand smoke, it is likely that far more than the reported 40% of children worldwide are exposed to toxic tobacco residue. Many studies have shown that thirdhand smoke is harmful in animals and in human cells. This evidence, along with what we know about the well-established risks of secondhand smoke, is enough to show the importance of studying the harms of thirdhand smoke exposure for people, especially children, so we can know the risks involved.
Dr. Ramírez González continued, saying “Thirdhand smoke is a public health issue of global concern. Although people are becoming more aware, more work is needed to make sure it is included in health and environmental policies. This is especially important now, since air pollution is a risk factor for COVID-19, and stay-at-home policies have led to more people smoking at home. It is our responsibility to take this opportunity to strengthen tobacco policies and increase public awareness of the impact of their smoking to protect the most vulnerable: our children.”