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The amount of nicotine in a cigarette depends on several factors, including the strength of the cigarette and how much smoke you are inhaling.
Cigarettes can contain anywhere between 8mg - 20mg of nicotine each [1], with the average amount of nicotine per cigarette around 12mg. This does not mean that when someone smokes a cigarette they end up with 8mg - 20mg in their bloodstream.
Researchers are a little conflicted in just how much nicotine makes it into the blood stream of a smoker, but estimates generally fall in the region of 1mg - 2mg per cigarette [2] [3]. Some of the reason for this will be variance between smokers, with some being much better at absorbing nicotine simply through the technique they use in smoking and inhaling. Clearly there must be quite a bit of nicotine in any exhaled cigarette smoke too.
How much nicotine is in a vape?
The amount of nicotine in a vape depends on what nicotine strength you choose. E-liquid strength ranges from zero nicotine, up to 20mg/ml, or 2%. This means there are 20 milligrams of nicotine present in each millilitre of e-liquid. Nicotine containing e-liquid in the UK is limited to 10ml bottles. So, a 10ml bottle at 12mg/ml (or 1.2%) has 120mg of nicotine in the whole 10ml bottle, or 1.2% of the liquid is nicotine.
How Much Nicotine is in One Puff of Vape?
The more interesting question is just how much nicotine is in a puff of an e-cigarette, and how much of that is a vaper able to absorb?
The lab tests we carry out for regulatory purposes indicate that the "nicotine yield" of a vape generally falls between 80 µg and 160 µg (a µg, or microgram, is 1000th of a milligram) for a 55 ml puff on a starter kit containing 1.8% (18mg/ml) e-liquid. This means that an average starter kit can provide as much nicotine as a smoker absorbs from a cigarette in just over 8 long, deep puffs when filled with 1.8% (18mg/ml) e-liquid.
Of course it's not quite as simple as that. Most people use e-liquid at lower strength than 1.8%, so need more puffs to reach the equivalent of a cigarette. Most vapers breathe out at least a little vapour after inhaling, meaning they are also losing nicotine that could otherwise be absorbed. Finally most vapers will not use as many as 8 long deep puffs in a single session.
Consequently it seems that most vapers will not get anything like the nicotine dose from a single "session" of vaping that they would get from smoking a cigarette. This goes a long way to explaining why vapers tend to use their e-cigarette more frequently than they used to smoke. They are no more addicted to nicotine, or indeed to vaping, they just need to vape more often than they smoked to satisfy the same nicotine cravings.
Reduced Nicotine and Nicotine Free Vapes
If you have started vaping to quit smoking, you have the option to slowly lower your nicotine strength, which with cigarettes is difficult without changing brands and monitoring your smoking habits.
While some vapers want to lower their nicotine strength over time, not everyone does.
You can start on an 18mg strength and lower this over time to a zero nicotine vape. But some people feel a need to stay on a higher strength to stop them from smoking. Both of these options are valid, just stick with the vape experience that stops you feeling a need to smoke.
Nicotine Salts
Most nicotine containing e-liquid uses something called 'freebase' nicotine. Freebase nicotine is the 'go-to' nicotine in most vape juices, and nicotine replacement therapies such as gums, patches and sprays.
Nicotine salts are the same form of nicotine, in a different chemical state. Nic salts are more like the nicotine naturally present in the tobacco leaf. With nic salt e-liquid you get smoother nicotine satisfaction with much less throat hit.
Nic salts are also absorbed by the body and taken into the blood stream much quicker than traditional freebase nicotine [4]. This sensation is much closer to the sensation of smoking.
How Much Nicotine Per Day is Safe?
When comparing cigarettes and vaping, nicotine is not the factor to be worried about. Cigarette smoke contain over 4000 chemicals, 44 of which are so carcinogenic or directly toxic that the WHO has prioritised them for measurement and reporting [5]. E-cigarette vapour typically contains just two of these chemicals (formaldehyde and acetaldehyde), and in both cases at levels that are far, far lower than in tobacco smoke, in fact under safe workplace exposure levels in many instances [6].
In answer to the more direct question of how much nicotine per day is safe, a reasonable starting point might be, "How much nicotine might it take to poison someone?" The ECHA currently gives an "acute toxicity estimate" (ATE) for nicotine via the oral route to be 5 mg/kg bw [7], meaning 5mg of nicotine for every kilogram of bodyweight of the person consuming the nicotine. So a person weighing 70kg that consumed 350mg of nicotine in one go would become extremely poorly. Halving that single exposure, and spreading out over a day should give a good margin for avoiding acute toxic effects. 175 mg per day certainly seems like it could be relatively safe, but can we be sure?
Nicotine and Smokers
Another approach might be to consider the times when smoking 40 cigarettes a day was fairly uncommon, but far from unheard of too. Many heavy smokers in those times would have been absorbing up to 80mg of nicotine into their bloodstream in a day. It is unfortunate that we can never know whether the nicotine did these people any harm at all, as at a population level their lives were more commonly shortened by the real harmful effects of smoking. It certainly did not seem that up to 80mg per day of nicotine was even comparable to the harms of tar and carbon monoxide, which caused COPD, lung cancer, heart disease and many other life threatening outcomes for those unfortunate smokers.
Given the latter approach is more cautious, we can be relatively confident that 80mg per day is a safe daily consumption of nicotine long term (remember you don't actually absorb all of it). Most regular (< 20 a day) smokers find they need around 2-3 10ml bottles of 1.2% (12mg/ml) or 1.8% (18mg/ml) nicotine e-liquid to stay smoke free every week. The average of these equates to just over 50mg of nicotine a day, which has been used without any negative consequences by a lot of people, and for a long time. 80mg per day definitely seems like a very safe limit given this fact.
This was a look at how much nicotine is in a cigarette. If you are ready to start vaping and need guidance on choosing the right nicotine strength, checkout our guide on what nicotine strength e-liquid you need.
References
[1]. Taghavi, S. et al. Nicotine Content of Domestic Cigarettes, Imported Cigarettes and Pipe Tobacco in Iran. Addiction and Health. 2012, 4(1-2): 28-35
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3905555/
[2]. Benowitz, N.L. Jacob P. Daily intake of nicotine during cigarette smoking. Clinical Pharmacology and Therapeutics. 1984 Apr; 35(4):499-504
https://pubmed.ncbi.nlm.nih.gov/6705448/
[3]. Mayer, B. How much nicotine kills a human? Tracing back the generally accepted lethal dose to dubious self-experiments in the nineteenth century. Archives of Toxicology. 2014; 88(1): 5-7
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3880486/
[4]. O'Connell, G. et al. A randomised, open-label, cross-over clinical study to evaluate the pharmacokinetic profiles of cigarettes and e-cigarettes with nicotine salt formulations in US adult smokers. Internal and Emergency Medicine. 2019; 14: 853-861
https://link.springer.com/article/10.1007/s11739-019-02025-3
[5]. Ticha, J. Wright, C. Rapid detection of toxic compounds in tobacco smoke condensates using high-resolution 1H-nuclear magnetic resonance spectroscopy. Analytical Methods. 2016, Issue 34.
https://pubs.rsc.org/en/content/articlelanding/2016/AY/C6AY00849F
[6]. Goniewicz, M.L. et al. Levels of selected carcinogens and toxicants in vapor from electronic cigarettes. Tobacco Control. 2014, Mar. 23(2): 133-139.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4154473/
[7]. ECHA Risk Assessment Committee Opinion. Adopted 10 September 2015Â
https://echa.europa.eu/documents/10162/23665416/clh_opinion_nicotine_5579_en.pdf/0103fadb-e945-4839-c4f4-17d20854adf0
