E-cigarettes appeal to so many people because they claim to offer all of the pleasure of smoking in an exponentially safer package, but anti-e-cig groups are always keen to point out that they contain carcinogens, even ‘helpfully’ pointing out that “that means it causes cancer.”
For those of us who've switched to e-cigarettes in the belief that they’re the safer option and after failing to reduce our tobacco consumption through FDA-approved methods, this casual bit of misinformation is actually a cause for concern.
Are we inhaling carcinogens and still exposing ourselves to similar risks of smoking a cigarette? Well, no. In fact, looking into the issue in more detail could even give you reason to accuse some anti-smoking advocates of outright propaganda.
What Are Nitrosamines?
One of the biggest problems with news reporting on the issue of nitrosamines in e-cigarettes is that to anybody who isn't chemically-minded, “nitrosamines” sound like alien entities intent on destroying your body, and nobody really knows what they are.
In chemical terms, they’re the result of a nitrosation reaction, which is where an amine group (often part of common biological molecules like amino acids) reacts with a nitrous oxide. The resulting compound is attached to two carbon and hydrogen containing groups, and these can vary in construction, creating numerous different “types” of nitrosamine. As you might expect, these are pretty common compounds, and they’re actually found in a wide range of products, as you’ll learn later on. They’re also often created in the human bowel, a process called endogenous nitrosation.
The first hint that there was some risk associated with nitrosamines came in the 1950s, when two researchers found that dimethylnitrosamine causes liver cancer in rats. When better technology was available, from the 1970s onwards, it was found that numerous products including cured meats (particularly fried bacon), beer, tobacco, rubber and some cosmetics contain nitrosamines. These were in pretty high levels, and eventually chemical strategies were formulated to reduce their prevalence in food. In the case of cured meats, they also imposed a limit of the amount of sodium nitrite (which supplies the nitrous oxide compounds) used as part of the curing processes. The limit was 120 parts per million (ppm).
There are tobacco-specific nitrosamines, which come from the tobacco plant (and have been detected in e-cigs), but these are essentially similar in chemical properties to other nitrosamines.
So, Everybody is Exposed Anyway?
In 1981, the National Academy of Sciences estimated that the average person was exposed to 1 microgram of nitrosamines per day. This is one millionth (0.000001) of a gram, so not that much. However, thanks to improvement of technology and processes, Richard A. Scanlan of the Linus Pauling Institute estimates that a more modern figure would be around 0.1 micrograms – a tenth of the amount predicted in the 1980s. In other words, yes, you will probably be exposed to plenty of nitrosamines anyway.
Nitrosamines in Rubber Products
Since nitrosamines are present in rubber products, keeping the quantities of them manufacturing workers are exposed to down is a major concern. Surprisingly, though, the nitrosamines can still affect you when you’re in close contact with rubber products. This means that the rubber tip of a baby’s bottle or pacifier can actually expose infants to nitrosamines. In the 1980s, this was often around 50-60 micrograms, and finally the FDA set a safe limit of 10 parts per billion (ppb) for each individual nitrosamine in baby bottle “nipples.” This means that with several different ones present, the amount could easily reach 30 ppb in the tip of a baby’s bottle.
If exposing babies to certain levels of nitrosamines is OK, it shouldn't be too much of a surprise that condoms can also expose both men and women to nitrosamines. Researchers calculated that if you have sex and use a condom, you’ll expose yourself (and your partner) to around 0.6 nanograms (a nanogram is a billionth of gram – 0.000000001) of nitrosamines.
Nitrosamines in Cosmetics
Many cosmetic products, such as lotions, shampoos and hair conditioners, also contain nitrosamines. Levels were much higher in the past, but even in 1991 a study revealed that 65 percent of products tested had at least 3 micrograms of nitrosamines.
Still not convinced you get plenty of nitrosamines anyway? Well, if you drink one liter of drinking water, you’re ingesting 0.7 nanograms of nitrosamines, which translated into a cancer risk of about one in a million. In swimming pools, the concentration is much higher, and in indoor pools it is often around 32 nanograms per liter.
So, Electronic Cigarettes Must Have Loads, Right?
Now you've learnt that safe sex, pacifiers, shampoo and even drinking water contain the carcinogenic nitrosamines; you might be expecting electronic cigarettes to possess them in staggering quantities. If that was true, the furor over the tobacco-specific nitrosamines in e-cigarettes might be justified. Thankfully for e-cigarette smokers everywhere, even a closer look at the most well-known negative study of e-cigarettes reveals that nitrosamines are nothing to worry about.
The FDA examines the contents of e-cigarette cartridges, and shockingly found that, like all other tobacco products, they can contain nitrosamines. The myth essentially arose as a result of the very choice wording of the associated press release, which claimed that “in several other samples, the FDA analyses detected carcinogens, including nitrosamines.” There is no mention of the quantities of them found, and there was a very good reason for that.
An analysis conducted by Michael Siegel found that the average cartridge (1ml of liquid) which tested positive contained just under 8.2 nanograms of nitrosamines, in total. For clarification, in a baby’s bottle, any one nitrosamine can be present in quantities of up to 10 parts per billion, which translates to 10 nanograms per gram. This also means that if you have sex with a condom, you’re exposing yourself to almost the same amount of nitrosamines you’ll find in an e-cigarette.
An important part of Dr. Michael Siegel’s analysis shows the amount of nitrosamines present in cigarettes. The results reveal that there are 11,190 nanograms of nitrosamines in a gram of Marlboro tobacco, in other words, it’s present in almost 1,400 times the amount you’ll find in an e-cigarette cartridge.
Since nicotine patches use the same pharmaceutical-grade nicotine you’ll find in e-cigarettes, as you might expect, nitrosamines are present in them too. In fact, the analysis shows that there are 8 nanograms of nitrosamines in a nicotine patch, which is virtually the same (to within a couple of ten billionths of a gram) as found in an e-cigarette cartridge. The FDA says that e-cigarettes are dangerous because they contain carcinogens, yet products they've approved contain the same carcinogens in essentially equal quantities.
The FDA Measured the Liquid, Not the Vapor
The biggest problem with the FDA study (and there are many), is that they looked specifically at the e-liquid, which means it would only really apply if we all drank it from the bottle. In a study which looked at the vapor from e-cigarettes, the researchers found that the quantities of nitrosamines were actually less than a thousandth of that found in the liquid directly.
Only one out of four nitrosamines were actually detectable in the test (indicating that if the others were present, it was in quantities less than 0.002 nanograms per milliliter), and the biggest concentration found out of all the tested products was 0.0073 nanograms per milliliter. This means that you’d have to vape your way through around 100 cartridges to take in the same amount of nitrosamines you’d find in a single liter of water. People consume around 0.1 micrograms per day anyway, which is equivalent to 100 nanograms. In other words, you’d have to consume over 13,000 e-cig cartridges (1 ml volume) to even double your daily consumption of nitrosamines.
Conclusion – Either Propaganda or Rank Idiocy
Yes, nitrosamines do appear to cause cancer in sufficient quantities, but as you've learnt, the amount an e-cig user inhales is in no way “sufficient quantities.” In fact, you’d have more of a chance of getting cancer from nitrosamines from having too much sex or replacing your electronic cigarette with a baby’s pacifier.
Safe limits have long been exposed for nitrosamines, and tolerance of low levels of tobacco-specific nitrosamines in products has been shown in respect to nicotine patches. This makes the FDA’s famous press release all the more disgusting, to the point where it is arguably propaganda – a purposeful misrepresentation of the situation designed to convert others to their point of view.
When it comes to anti-smoking groups criticizing e-cigs for containing nitrosamines, it could be the same cynical mechanism operating, or they could genuinely misunderstand the risks. Perhaps nobody has ever told them that the quantities are absurdly, nigh-on-undetectably low, or perhaps people have and they were just too dim to understand the obvious lack of risk.
Either way, if somebody still insists that the nitrosamines in e-cigarettes is something to worry about after becoming aware of the facts in this article, they are either idiots or people who just plain hate anything that looks like smoking.