An Investigation and Study of the Harms of E-cigarettes

E-cigarettes have emerged in modern times as a trendy new practice. They were originally invented by Chinese people, later improved overseas, with many e-liquids launched; many traditional tobacco companies have also switched to making e-cigarettes.

Overseas, e-cigarettes are not merely a substitute for tobacco but a concept of "playing with vapor." Because they fall outside traditional tobacco products, many smoking bans do not prohibit e-cigarettes, thus meeting the needs of people who cannot do without tobacco.

E-liquids broadly come from three places: one is Europe and America, characterized by adding traditional flavorings, with complex layers of taste; another is Indonesia, Malaysia, and the like, mainly fruit-flavored; and another is domestic. Domestic e-liquids feature a single flavor done relatively strongly; many imitate foreign e-liquids—some nearly indistinguishable, some poorly imitated, and some that develop their own brand style.

Although there are 0 mg nicotine e-liquids, most smokers still use 6 mg, 9 mg, 12 mg and the like.

Taking 6 mg as an example: 6 mg means 6 mg of nicotine per milliliter. A bottle of e-liquid is usually around 30 ml, while an e-cigarette atomizer typically has a capacity of 5 ml.

Smokers who once went through a pack a day, when using an atomizer to draw e-liquid, typically consume about 5 ml of e-liquid per day—that is, 30 mg of nicotine.

Take Yuxi as an example of traditional cigarettes: each cigarette contains 1 mg of nicotine, so 20 cigarettes contain 20 milligrams. According to foreign smoking-machine simulation tests, the ratio of nicotine absorbed from e-cigarettes versus cigarettes is about 5:8.

So how many milliliters of 6 mg e-liquid equal one pack of cigarettes? We can calculate: x * 0.5 = 20 * 0.8

From this we derive: x = 20 / 0.5 * 0.8 = 40 * 0.8 = 32 mg

Thus, one cigarette containing 1.0 mg of nicotine is roughly equivalent to 5 ml of 6 mg e-liquid.

In actual use, however, atomizers need cleaning and the like; hands inevitably get e-liquid on them, and nicotine in e-liquid can be absorbed through the skin. So the actual nicotine intake is greater than the nicotine content of a pack a day.

The greatest harms of traditional tobacco lie in tar, heavy metals, carcinogenic phenolic compounds, carbon monoxide, and so on. Harmful components are generally thought to number over two thousand kinds, posing relatively great harm to the population.

E-cigarettes are usually marketed as healthy and safe, yet related research shows that while e-cigarettes are somewhat less harmful than traditional tobacco, the risk of harm they produce is not low.

The first risk: e-cigarette e-liquids use large amounts of propylene glycol, yet how great a negative effect this substance has on the human body is not yet known.

Although experiments have shown no obvious effects when laboratory animals are placed in propylene glycol environments, this cannot fully prove propylene glycol is harmless, because propylene glycol itself is of low toxicity—injecting it into a mouse would directly kill it.

The second risk: e-liquid flavorings have many hidden dangers. Whether flavorings are imported or not, natural or chemically prepared, the key point is whether the ratios in safety requirements are observed.

Because the ratios and dosages of e-liquid flavorings are mostly undisclosed, both foreign and domestic e-liquids may see manufacturers add flavorings beyond safety requirements to cater to consumers' taste thresholds.

Another hidden danger: many flavorings are produced in small workshops with many impurities, most of which are harmful to the human body. If merchants cut costs by using such flavorings, it will harm people's health.

One final hidden danger: e-liquids with a creamy or nutty taste usually contain diacetyl. Once there was a report that inhaling diacetyl into the lungs might cause "popcorn lung" disease—though traditional tobacco also contains this substance, and its content is tens of times higher than in e-liquid.

Besides risks, relatively certain harms also exist. Related papers point out that when cytotoxicity tests were conducted comparing e-cigarettes with traditional tobacco, e-cigarettes were found to be 50% less toxic than traditional tobacco, and the cytotoxicity of e-liquid is directly related to how much nicotine it contains.

Overall, disregarding the effects of propylene glycol, e-cigarettes currently appear much less harmful to the human body than traditional tobacco—but one cannot say e-cigarettes are healthy; one can only say they are not as bad as traditional cigarettes.

If the goal is quitting smoking, relatively sound suggestions for using e-cigarettes and e-liquid are:

1. You may occasionally try creamy and nutty flavored e-liquids, but not too much.

2. Vanilla flavor may be tried occasionally, as its cytotoxicity is more pronounced than other flavors.

2. Where the flavor is tolerable, choose e-liquid with lower nicotine content whenever possible. Old smokers who go through a pack a day are advised to start with 6 mg e-liquid rather than 12 mg.

3. E-liquids are mostly already quite fragrant. If possible, it is best not to inhale them into the lungs—merely hold them in the mouth to taste as with a cigar, then spit them out, which can reduce the risk of lung damage.

4. Once accustomed to not inhaling into the lungs, switch immediately to 1 mg or 0 mg e-liquid.

5. If you can, use ready-made atomizers directly. Try not to play with DIY atomizers, or you may become addicted and, through repeatedly testing your own creations, end up drawing more e-liquid.

6. Drink plenty of water—first to relieve thirst caused by propylene glycol in the e-liquid, and second to accelerate nicotine metabolism.

7. Do not play with stick-shaped devices such as mechanical mods if you are not well familiar with them. They carry certain dangers—for example, reverse battery polarity can cause explosions.

8. There is no e-liquid that truly replicates the exact taste of traditional tobacco, so do not waste time and money searching for one. Vaping various e-liquids is like sampling various beverages all the time—only they additionally contain nicotine, which is why they meet the need.