- Smoke-free products like vapes, heated tobacco products (HTPs) and nicotine pouches expose users to far fewer harmful chemicals than cigarettes
- Chemical exposure from HTPs is estimated to be 40 to 50 times lower than from cigarettes; for vapes, 100 to 500 times lower
- Using HTPs outdoors produces half the air pollution of cigarettes and doesn’t raise harmful chemicals in users or bystanders
- Biomarker studies confirm that smokers who switch to smoke-free products carry much lower levels of toxic substances in their bodies
Smoke-free products such as vapes, heated tobacco products (HTPs) and nicotine pouches expose users and bystanders to far fewer harmful chemicals than cigarettes, according to two new scientific studies.
The research adds evidence that switching away from combustible tobacco can reduce health risks and environmental exposure to toxic substances.
Study one: toxic exposure falls when smokers switch
The first study, published in Internal and Emergency Medicine and led by German chemist Prof. Dr. Reinhard Nießner, reviewed a wide range of toxicological data on smoke-free products (SFPs).
The review highlighted that cigarette smoke contains thousands of harmful and potentially harmful chemicals, including known carcinogens, while emissions from vapes, HTPs and nicotine pouches are far lower.
Laboratory tests confirmed that cigarette smoke can damage cells and DNA, whereas vapours from vapes and HTPs were significantly less toxic.
Data from the German Federal Institute for Risk Assessment (BfR), alongside regulators in the U.S. and the Netherlands, showed that HTPs emit lower levels of harmful aldehydes and volatile organic compounds (VOCs) than cigarettes.
Vapes were found to deliver nicotine at levels similar to smoking but with far fewer toxicants. Nicotine pouches contained virtually undetectable levels of tobacco-specific nitrosamines (TSNAs), the main cancer-causing chemicals in tobacco, with levels comparable to medically approved nicotine replacement therapies such as gums and patches.
The study also reviewed biomarker research, which measures chemicals in users’ blood, urine and saliva. Smokers who switched entirely to SFPs showed significantly lower levels of harmful substances than those who continued smoking.
Mathematical modelling of cancer potency based on these chemical reductions suggested that exposure from HTPs is 40 to 50 times lower than cigarettes, and for vapes it’s 100 to 500 times lower. Nicotine pouches, with their limited chemical complexity, are assumed to be similarly low risk.
The study noted that smoking prevalence remains high in Germany, with more than 20 million adults still smoking, many of whom have little desire to quit. For these individuals, access to less harmful alternatives could substantially reduce toxic exposure.
Study two: cleaner air with heated tobacco outdoors
The second study, published in Analytical Methods and led by researchers at the University of Valencia, focused on the environmental impact of HTPs when used outdoors.
Researchers used air sensors to measure fine particulate matter (PM10 and PM2.5), which are linked to respiratory and cardiovascular disease, as well as volatile organic compounds in ambient air. They also collected and analysed exhaled breath from both users and bystanders to measure chemical exposure.
The study found that heated tobacco produced roughly half the particulate pollution of cigarettes. Levels of VOCs in the air and in the breath of nearby people did not increase. By contrast, passive exposure to cigarette smoke caused substantial rises in harmful substances in bystanders’ breath.
The Valencia team also conducted chemical analysis to confirm that no additional toxic compounds were introduced by HTP use. They observed a notable reduction in nicotine in the exhaled breath of HTP users compared with cigarette smokers.
While the study stressed that heated tobacco is not risk-free, the results suggest that its use outdoors has a much smaller effect on air quality and passive exposure than traditional cigarettes.
Combined findings
Together, the two studies suggest that smoke-free products deliver nicotine with a fraction of the toxic exposure caused by smoking. Heated tobacco reduces exposure to cancer-related chemicals for users and generates less outdoor air pollution, while vapes and nicotine pouches show reduced cell-damaging effects in laboratory and biomarker studies.
The research reinforces the potential for smoke-free products to lower harmful chemical exposure for both smokers and people around them.
These findings support harm reduction strategies by highlighting that alternatives to combustible tobacco can reduce health risks and environmental impact, particularly for adult smokers who are unable or unwilling to quit nicotine entirely.
