Searching in Vaping Liquids for the Component That Killed the Spy

An Australian chemist investigates vaporizers for a highly toxic chemical in combustible cigarettes. Does her research make sense?

Sarah Mullins, an Australian chemist specializing in radiation, meticulously examines vaporizers for traces of polonium-210, a radioactive component found in tobacco. Her mission is to determine if this feared component of cigarettes is also present in vapers. But is it valid to raise alarms and cause concern among those who see vaping as a healthier alternative to harmful cigarettes? Is it justifiable to sow fear based on these findings? Let’s find out how solid these fears are and why Mullins silences our questions.

In one of the modern laboratories of the Queensland Health Forensic and Scientific Service, Sarah Mullins, a radiation specialist chemist of the Australian state agency, spends her days examining confiscated vaping devices for a component relatively unknown to the general public: polonium-210, a radioisotope naturally found in tobacco cigarettes.

“Imagine,” Mullins began, with a serious look during an interview with a 7NEWS reporter, “smoking two packs of cigarettes exposes you to radiation equivalent to a chest X-ray. Our mission here is to quantify how much, if any, of this dangerous element might be lurking in vaporizers.”

Mullins’ concern, which establishes a correlation, is that polonium-210, a volatile metal, can be found in tobacco smoke, accumulate in smokers’ lungs, and be one of the culprits for lung cancer. This occurs because the sticky tar of tobacco adheres to the small airways in the lungs (bronchioles) and traps these radioactive substances.

But what is polonium-210?

Derived from polonium (Po, atomic number 84), this atom is inherently radioactive. Due to its unstable nature, these atoms decay over time, emitting high-energy particles. According to the explanation of the Los Alamos National Laboratory, one of the leading scientific institutions worldwide, especially known for its key contribution to creating the first nuclear bomb, polonium-210 easily becomes vapor because it melts at low temperatures. Half of it evaporates in 45 hours at about 53° C (127° F). As it decomposes, these atoms can release alpha particles powerful enough to damage or destroy cellular genetic material.

According to a European study, unlike neutrons, X-rays, or gamma rays, alpha particles travel only a few centimeters in the air and cannot penetrate the skin. However, if ingested or inhaled, they can cause severe cellular damage and may be related to many cases of lung cancer.

Polonium-210 occurs naturally in the environment. It forms when uranium-238 and radium-226, two other radioactive materials in the Earth’s crust, decompose. Although its half-life is about 138 days, its toxicity is quite high. A testament to its dangerous nature and lethality was the poisoning of former Soviet spy Alexander Litvinenko. In November 2006, Litvinenko was poisoned with polonium-210 while drinking tea in a London hotel and died several days later.

However, in the world of smoking, it has been determined that the average concentration of polonium-210 activity in cigarettes is 16.6 mega becquerels per cigarette. Furthermore, the average annual effective dose for a pack-a-day smoker is estimated to be between 193 and 251 microsieverts (mSv, a unit of radiation dose measurement).

In this sense, researchers from the University of Massachusetts indicated that someone who consumes a pack and a half (30 cigarettes) daily receives a radiation dose of 80 mSv per year in the bronchial epithelium, specifically in the bifurcation areas. This dose is comparable to what would be received from 300 chest X-rays annually.

To give an idea of the problem, the International Commission on Radiological Protection (ICRP) recommends a radiation exposure limit for the general public of 100 mrem or 1 mSv per year (the term “mrem” means millirem, which is a unit of measurement for radiation dose).

Does this research make sense?

It is known that polonium-210 is present in cigarettes, including smoke, and that the tobacco plant accumulates small concentrations mainly from the soil’s natural radioactivity. However, not exclusively, farmers use fertilizers that contain a substance called radium, a close relative of polonium-210, in the production process.

An anonymous official from a company subcontracted by a major tobacco company in southern Brazil explained: “As the tobacco grows, this radium and its similar already in the ground bind to the plant. Then, when products like cigarettes are made with that tobacco, these substances remain in them.” In other words, tobacco absorbs substances from the fertilizers and the soil, ending up in smoked products.

Between 6.5 and 22% of the polonium-210 present in cigarettes was also found in the smoke consumed when smoking. However, polonium is just one of at least 69 carcinogenic and potentially lethal chemical compounds present in tobacco smoke.

“It is known that polonium-210 can be found in the environment, including minerals and organic matter. It is also present in tobacco smoke, as well as in fertilizers containing rock phosphates, which can be absorbed by plants, as happens with tobacco. It does not seem likely that it could be found in electronic cigarettes. Perhaps this doubt is being investigated,” he added.

Polonium-210 is highly radiotoxic and dangerous. Because of this, science has raised relevant questions and made discoveries about the relationship between polonium-210 and tobacco and the problems associated with smoking.

However, vaping products do not contain tobacco. So, we asked Sarah Mullins: How could vapers be exposed to polonium-210 if they do not consume tobacco? Does processed nicotine derived from tobacco plants contain polonium-210 or another radioactive substance in worrying amounts? Our editorial team tried to contact Sarah Mullins on several occasions, but she did not respond to our questions: