The concept of a “smokeless” vape stems from a misunderstanding of the output produced by electronic nicotine delivery systems. Vaping devices do not produce smoke; the visible cloud that is exhaled is an aerosol. Understanding this distinction is key, as certain devices and techniques can significantly reduce the visibility of this output. Regardless of visibility, the aerosol still contains various chemical compounds inhaled by the user.
Smoke Versus Aerosol Clarifying the Difference
The fundamental difference between a traditional cigarette and a vaping device lies in how the inhalable substance is generated. Traditional cigarettes create smoke through combustion, the high-temperature burning of tobacco and paper. This process generates solid particulate matter and thousands of chemicals, many of which are known carcinogens.
Vaping devices produce an aerosol by heating e-liquid until it vaporizes. This aerosol consists of fine liquid droplets suspended in the air, primarily composed of propylene glycol (PG) and vegetable glycerin (VG). Since the process does not involve burning, the output lacks the solid carbon particles found in smoke, but it is not simply “water vapor.”
Although the public commonly uses the term “vapor,” the scientifically accurate term for the output is “aerosol.” While cigarette smoke is also technically an aerosol, the composition is vastly different due to the absence of combustion in vaping. The liquid-based aerosol from vaping contains significantly fewer harmful chemicals compared to those found in cigarette smoke.
Devices and Techniques for Minimizing Visible Output
Users seeking a discreet experience are engaging in “stealth vaping,” which focuses on minimizing the visible aerosol cloud. This is achieved through a combination of hardware selection, e-liquid ratios, and inhalation technique. Low-wattage devices, such as small pod systems, are specifically designed to operate at lower power settings.
These lower power settings produce a smaller, less dense aerosol cloud compared to the large, high-power “mod” devices favored by “cloud chasers.” Many stealthier devices are designed for a mouth-to-lung (MTL) draw, which mimics the restricted pull of a traditional cigarette. The MTL technique results in less aerosol production than the direct-to-lung (DTL) technique.
The composition of the e-liquid also plays a major role in the visibility of the cloud. E-liquids use a ratio of Vegetable Glycerin (VG) to Propylene Glycol (PG). High VG liquids (70% VG or higher) are thicker and produce large, dense, billowing clouds.
Conversely, e-liquids with a higher proportion of PG, such as a 50/50 ratio, create a thinner, less voluminous cloud that dissipates quickly. Users aiming for minimal visible output often choose devices optimized for higher PG liquid, as this combination results in the most discreet aerosol production.
Understanding the Contents of Vaping Aerosol
Regardless of the aerosol cloud’s visibility, the user inhales a mixture of chemical compounds. The majority of the aerosol consists of the base liquids: Propylene Glycol (PG) and Vegetable Glycerin (VG). Nicotine is present if the e-liquid contains it, along with various flavorings that make up roughly 3% of the constituents.
The heating process, even at lower temperatures, can lead to the formation of trace contaminants. Carbonyl compounds, such as formaldehyde, can be generated when the e-liquid is heated, particularly at higher temperatures or if the device malfunctions.
Studies have also detected trace amounts of heavy metals in the aerosol, including nickel, chromium, and lead. These metals are believed to be released from the metallic heating coil within the device as the e-liquid is heated.