The latest findings of the Chinese research team: the impact of e-cigarettes on the respiratory system is far lower than that of cigarettes

On October 8, the research team of the School of Pharmacy of Sun Yat sen University published a paper in the core global toxicology journal ARCHIVES OF TOXICOLOGY, pointing out that at the same nicotine dose, the harm of electronic smoke sol to the respiratory system is less than that of cigarette smoke.

The impact of electronic cigarettes and cigarettes on health has been a hot topic in the field of public health in recent years. In this study, the research team of Sun Yat sen University for the first time compared the effects of cigarette and electronic cigarette on lung function, inflammatory factors and protein expression in mice with the same nicotine content, filling the gap in scientific research in related fields.

The researchers selected RELX Yueke watermelon flavored electronic cigarette and a commercial cigarette as samples, and randomly divided 32 mice into 4 groups. They were exposed to clean air, low-dose electronic smoke sol, high-dose electronic smoke sol, and cigarette smoke for 10 weeks, and analyzed their multiple indicators.

The pathological section of lung tissue showed that the lung coefficient of the mice exposed to cigarette increased significantly, and the shape of trachea changed, suggesting that the respiratory system might have pathological changes. As a contrast, the lung coefficient of mice exposed to electronic smoke did not change significantly, and the shape of trachea did not change.

The lung function test found that cigarette exposure resulted in significant abnormalities of several lung function indicators in mice, but only one indicator in the electronic cigarette group decreased. At the same time, pathological results showed that both cigarettes and electronic cigarettes may cause lung abnormalities in mice, but the damage caused by cigarettes is more obvious.

The detection of serum inflammatory factors and transmission electron microscopy showed that both cigarettes and electronic cigarettes can cause airway inflammation, but cigarettes are more harmful. Even if the nicotine content is 2 times that of cigarettes, the pathological damage caused by electronic cigarettes to the trachea of mice is also smaller.

Finally, the researchers also conducted proteomic analysis of mouse lung tissue. The results showed that the changes of differential proteins caused by cigarette were more concentrated in the inflammation related pathways, while the abnormal expression caused by electronic cigarette was less, and had less impact on the inflammation signal pathways.
The researchers said that the research results clearly showed that exposure to cigarette and electronic cigarette with large inhalation dose was harmful to the respiratory system. But at the same nicotine dose, the harm of electronic smoke sol to respiratory system is less than that of cigarette smoke.

As no burning is required, electronic smoke will not produce tar, which is generally regarded as a harm reduction alternative by the medical community. The US Centers for Disease Control and Prevention (CDC) clearly pointed out on its official website that switching from cigarettes or other combustible tobacco products to electronic cigarettes may have potential benefits for adult smokers who are not pregnant.

However, due to the short time, the research on electronic cigarette is still insufficient. In recent years, many scientific research institutions and public health organizations have focused on the potential impact of electronic cigarettes.
In January 2022, researchers from the US Food and Drug Administration (FDA) published a paper in Tobacco Control, pointing out that electronic cigarettes are less harmful than cigarettes. After smokers switch to electronic cigarettes, the level of biomarkers of various carcinogens in their urine will drop, up to 95%.

In September 2022, the Eighth Independent Report on Nicotine Electronic Cigarette Research released by the Ministry of Health and Social Health of the United Kingdom pointed out that compared with cigarettes, the exposure to harmful substances caused by electronic cigarettes was significantly reduced, which could significantly reduce the exposure to biomarkers related to cancer, respiratory system and cardiovascular disease risks.

The research team of Sun Yat sen University said that this study comprehensively and systematically analyzed the relative safety of electronic cigarettes at the animal level, and hoped to carry out more clinical studies in the future to objectively and deeply evaluate the long-term impact of electronic cigarettes.