Even just 30 minutes of exposure to secondhand smoke is enough to trigger inflammatory processes in the body, which in turn are responsible for tissue damage. This emerges from a very recent scientific research published in the International Journal of Environmental Research and Public Health by an Italian team from the University of Perugia (Stabile et al, Int J Environ Res Public Health, Aug 2022).
The harms of passive smoking
It is called environmental tobacco smoke and is the cigarette smoke that is involuntarily inhaled by people, even those who do not smoke. Exposure to environmental cigarette smoke belongs to group 1, that is, the group that contains all certain carcinogens according to the IARC, which is the international agency for research on cancer. Prolonged exposure to secondhand smoke can cause respiratory and cardiovascular diseases but also cancers in adults and children. The anti-smoking laws of recent years have made it possible to take incredible strides to protect non-smokers from the risks of secondhand smoke. However, exposure to secondhand smoke remains a serious problem since there is no control over what happens in private homes or cars. To give some examples, how many children or adults are exposed to secondhand smoke from their parents' or partner's cigarettes? How many times, in order to live in peace, have we preferred to remain silent in front of a friend who gave us a ride in the car and who lit a cigarette? Or how many times, at parties with friends when the rooms became smoke rooms we didn't say anything so as not to cause annoyances? Maybe even thinking that this was only for a short time ... Well, according to new scientific research we now know that even a short exposure to cigarette smoke can cause damage to our body.
Damage even after a short exposure to secondhand smoke, the study
Scientists started from the consideration that there are countless studies that report the damage of prolonged and continuous exposure to secondhand smoke. Instead, only a few studies have devoted themselves to the effects of secondhand smoke after short exposures. In general, these studies have evaluated the action of short but recurrent exposures, in any case ascertaining damage to the immune, cardiovascular and endocrine systems. But what happens in our body after just one, short exposure to secondhand smoke? To answer this question, researchers from the University of Perugia recruited 21 healthy subjects, who were not normally exposed to secondhand smoke and without respiratory diseases. Volunteers were led into a 6x5x4m room, 120 cubic meters in all. In the center of the room was a table with an ashtray where a cigarette was burned. Well, already after 30 minutes, the blood samples collected showed an increase in circulating pro-inflammatory substances, which even doubled. In particular, a substance was increased, the p75NTR receptor, which induces chronic inflammation in the tissues. The increase of this receptor is also observed in smokers, therefore it can be said that passive smoking induces the same pro-inflammatory mechanisms both in those who actively smoke and in those who breathe passive smoke. In the volunteers under examination, in the absence of further exposure to secondhand smoke, the values of the pro-inflammatory substances returned to normal after one day.
Conclusions
The study is yet another proof that passive smoking, even if only for short periods of time, is harmful and should always be avoided. In fact, 30 minutes of exposure to secondhand smoke are enough to trigger inflammatory processes that increase the levels of chronic inflammation. Chronic inflammation is the real enemy, fed by an unbalanced diet, stress, lack of sleep and, of course, smoking and passive smoking, over time weakens our natural defenses and increases the risk of cardiovascular disease and cellular degeneration.
