digital worldz
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Many people often ask me why the mg in e-cigs are a lot highr then cigarettes. Well its a complicated reason and calculation
I recently read the following on the ECITA Site. Hopefully it should help people on here
How much nicotine is absorbed following electronic cigarette use?
Posted on January 28, 2013 by admin
by Tom Pruen
It’s an interesting (and important) question, but it is also one of the biggest blank spots in the science about e-cigs. It is a question that is currently without an answer (as far as I am aware, and I do my best to keep up with the state of research).
So what do we know?
We know the average nicotine delivery for a tobacco cigarette is 1.4mg (this is the actual nicotine delivered to the consumer, not the machine estimated delivery of 1mg), and that on average cigarettes contain 10.2mg[ii] of nicotine. This means that cigarettes have 14% efficiency for nicotine delivery.
A pack a day (PAD) smoker will consume 20 cigarettes of 1.4mg each for a total of 28mg/day (out of 204mg in the cigarettes they have consumed). One of the reasons that the delivery of nicotine from cigarettes is so low is that the delivery method involves combustion and hence some of the nicotine is burned. There is also detectable nicotine in second-hand smoke, so not all the nicotine that is made available is actually absorbed.
So how does this relate to electronic cigarettes?
From online discussions[iii], we know that most vapers were 1 to 2 PAD smokers, and now use 2 to 3ml of 24mg liquid, or 3 to 4ml of 18mg liquid (with a tendency to use either more or less depending on increased or decreased strength). We know that there is no combustion involved, so how much nicotine is actually delivered?
We know it is more than none[iv] and less than 100%[v] since nicotine is detectable in the exhaled vapour. The levels of nicotine in exhaled vapour are low. In fact, nicotine was detected in vapour exhaled directly into a 10 litre test vessel but was not detected in an 8m3 room testv. Indeed, the Clearstream study[vi] confirms that nicotine levels found in indoor air after vaping are extremely low:
“Nicotine concentration in the air from the traditional cigarettes was on average 0.034mg/m3, while for the electronic cigarette it was less than 0.001mg/m3”.
But I digress….
If electronic cigarettes delivered 100% of the nicotine contained in the liquid, this would equate to 48-72mg/day. This would be a lot (although the indications for the Nicorette inhaler are for 6-12 10mg capsules/day, for a maximum of 120mg), but we know it must be less than this…… so how much is it?
This where we move beyond provable science and into the rather more vague world of assumption (or possibly expert opinion).
We know that in tests of vapers in an ad-lib vaping session, blood nicotine levels rose to those found following smoking cigarettesiv (15ng/ml[vii]).
Given this, we can assume that vapers will consume enough nicotine in a vaping session to reach this level, as they would if they were smoking (i.e. they self-titrate to the level they desire). If we assume that this would result in a nicotine intake per day of around the same amount, what percentage delivery effectiveness does this give us?
A PAD equivalent vaper would be using approx. 2ml of 24mg liquid to obtain approx. 28mg of absorbed nicotine, so an efficiency of about 60%.
A 1.5 PAD equivalent vaper would use approx. 3ml of 24mg (or 4ml of 18mg) liquid to obtain approx. 42mg of nicotine, with the same efficiency.
This would seem to fit well with the experiences of vapers in online communities with regard to their usage patterns.
This seems likes an eminently reasonable set of assumptions to give us a guide to expected intake, but hopefully this question will be answered by an actual scientific study in order to provide real data.
I recently read the following on the ECITA Site. Hopefully it should help people on here
How much nicotine is absorbed following electronic cigarette use?
Posted on January 28, 2013 by admin
by Tom Pruen
It’s an interesting (and important) question, but it is also one of the biggest blank spots in the science about e-cigs. It is a question that is currently without an answer (as far as I am aware, and I do my best to keep up with the state of research).
So what do we know?
We know the average nicotine delivery for a tobacco cigarette is 1.4mg (this is the actual nicotine delivered to the consumer, not the machine estimated delivery of 1mg), and that on average cigarettes contain 10.2mg[ii] of nicotine. This means that cigarettes have 14% efficiency for nicotine delivery.
A pack a day (PAD) smoker will consume 20 cigarettes of 1.4mg each for a total of 28mg/day (out of 204mg in the cigarettes they have consumed). One of the reasons that the delivery of nicotine from cigarettes is so low is that the delivery method involves combustion and hence some of the nicotine is burned. There is also detectable nicotine in second-hand smoke, so not all the nicotine that is made available is actually absorbed.
So how does this relate to electronic cigarettes?
From online discussions[iii], we know that most vapers were 1 to 2 PAD smokers, and now use 2 to 3ml of 24mg liquid, or 3 to 4ml of 18mg liquid (with a tendency to use either more or less depending on increased or decreased strength). We know that there is no combustion involved, so how much nicotine is actually delivered?
We know it is more than none[iv] and less than 100%[v] since nicotine is detectable in the exhaled vapour. The levels of nicotine in exhaled vapour are low. In fact, nicotine was detected in vapour exhaled directly into a 10 litre test vessel but was not detected in an 8m3 room testv. Indeed, the Clearstream study[vi] confirms that nicotine levels found in indoor air after vaping are extremely low:
“Nicotine concentration in the air from the traditional cigarettes was on average 0.034mg/m3, while for the electronic cigarette it was less than 0.001mg/m3”.
But I digress….
If electronic cigarettes delivered 100% of the nicotine contained in the liquid, this would equate to 48-72mg/day. This would be a lot (although the indications for the Nicorette inhaler are for 6-12 10mg capsules/day, for a maximum of 120mg), but we know it must be less than this…… so how much is it?
This where we move beyond provable science and into the rather more vague world of assumption (or possibly expert opinion).
We know that in tests of vapers in an ad-lib vaping session, blood nicotine levels rose to those found following smoking cigarettesiv (15ng/ml[vii]).
Given this, we can assume that vapers will consume enough nicotine in a vaping session to reach this level, as they would if they were smoking (i.e. they self-titrate to the level they desire). If we assume that this would result in a nicotine intake per day of around the same amount, what percentage delivery effectiveness does this give us?
A PAD equivalent vaper would be using approx. 2ml of 24mg liquid to obtain approx. 28mg of absorbed nicotine, so an efficiency of about 60%.
A 1.5 PAD equivalent vaper would use approx. 3ml of 24mg (or 4ml of 18mg) liquid to obtain approx. 42mg of nicotine, with the same efficiency.
This would seem to fit well with the experiences of vapers in online communities with regard to their usage patterns.
This seems likes an eminently reasonable set of assumptions to give us a guide to expected intake, but hopefully this question will be answered by an actual scientific study in order to provide real data.
