Dr. Murray Laugesen: How much nicotine do we absorb?

[DC2]

I've been seeing two different numbers floating around all over the place.

His Ruyan study is often quoted as saying we absorb 10% of the nicotine from vaping.
He is also being quoted as saying 98% of the nicotine is absorbed, so we only exhale 2% of what we took in.

Can anyone tell me what I'm missing here?

 

[wrigleyvillain]

Got a link?

 

[DC2]

Got a link?

I've never found an exact link that specifically and clearly cites the numbers others often quote.

But I do know that the 10% number has been considered common knowledge since before I got here.
And I've been hearing some people lately who know their stuff talking about the 98% thing.

 

[DC2]

By the way, I do think this is the study that both numbers in question are supposed to stem from...
http://www.healthnz.co.nz/RuyanCartridgeReport30-Oct-08.pdf

 

[Ande]

As I understood it at the time (don't have a second to go check in the article now, so correct me if I'm wrong):

That's "10% of the nicotine that we would get from a similar sized puff on a real cigarette." (ie, vaping provides much less nicotine, puff for puff, than traditional cigarette smoking)

And "98% of the nicotine in the vapor is absorbed by the vaper." (ie, we get most of whatever nicotine is in the vapor, and only trivial amounts are exhaled.)

Both statements seem plausible, and not in any way contradictory. When looking at percentages, you always have to as "x percent of what?

The conclusion seems to be that puff for puff, there's a lot less nic in e-cig vapor than in cigarette smoke, but that we're absorbing a high percentage of what there is.


Best,
Ande

 

[swedishfish]

According to people that have posted blood test results that doesn't seem to be the case.

 

[jayvolt]

What was the case for the peoe that posted the blood test results? I am curious now.

 

[swedishfish]

Here's just one thread. If you read the whole thread, lots of great info

http://www.e-cigarette-forum.com/fo...3-blood-test-lab-results-nicotine-levels.html

 

[DC2]

As I understood it at the time (don't have a second to go check in the article now, so correct me if I'm wrong):

That's "10% of the nicotine that we would get from a similar sized puff on a real cigarette." (ie, vaping provides much less nicotine, puff for puff, than traditional cigarette smoking)

And "98% of the nicotine in the vapor is absorbed by the vaper." (ie, we get most of whatever nicotine is in the vapor, and only trivial amounts are exhaled.)

Both statements seem plausible, and not in any way contradictory.[/I]

The conclusion seems to be that puff for puff, there's a lot less nic in e-cig vapor than in cigarette smoke, but that we're absorbing a high percentage of what there is.

That would mean that if a person were using 3ml of 18mg juice per day, they would be getting 53mg worth of nicotine.

And that would be about 2.5 packs per day of full strength Marlboro 100s.
Or as many as 5 packs per day of Marlboro ultra-lights cigarettes.

That would mean that most of us are getting WAY more nicotine than we used to.

So while there may be nothing contradictory about looking at it that way, if looked at that way it would change everything.
But also, I have never understood it to be taken that way.

I sure hope someone comes along that knows exactly where these numbers come from.

 

[Robin Macri]

Thats a scary thought DC2!

 

[wv2win]

I think I can safely state that it is more than 10% and less than 98%! I hope that helps.

 

[DC2]

Thats a scary thought DC2!

Don't worry, it can't be right, I don't think.


But we'll get to the bottom of it eventually.

I'll PM some people who should have a better understanding of where these numbers come from.
I was hoping they'd see this thread and stop by, and maybe they will eventually, but since they haven't yet...

 

[Vocalek]

There is a difference between how much nicotine is in a puff (10% of the amount in a puff of cigarette smoke) and how much nicotine is absorbed from each puff (say 98%).

Dr. Laugesen did say that an e-cigarette user would need to take more puffs than a tobacco cigarette smoker to get the same amount of nicotine.

Keep in mind that there are a lot of variables that will affect how much nicotine is in a puff. The FDA found different levels from different puffs. So such things as the temperature of the atomizer or the charge amount left in the battery may be affecting differences. There are also a lot of variables that will affect how much nicotine any particular person absorbs from a puff of vapor. How big a puff are we talking about? I tend to take short puffs, but I know some folks who sit there and inhale for at least 5 seconds before they exhale clouds of vapor. How long do you hold the vapor in your mouth before inhaling it? Absorbtion rates differ in the mouth, upper respiratory system, and deep in the lungs.

Why are you worried about how much measurable nicotine you are taking in from vaping? Did you worry about how much nicotine you were getting when you smoked?

Nicoitne intake tends to be self-regulating. Your body lets you know when you need more and it also lets you know when you took in too much too fast.

 

[swedishfish]

Not to speak for DC2, but he's an extremely helpful well informed person. This question does get asked a lot in the new member section and you sort of want to make sure you're giving a person factual information.

I realize you were probably making a general statement and not specifically to DC2.

I happen to agree with you. As smokers we 'knew' when we were craving an analog. We also know that feeling when that need was satiated. I think everyone vapes more than they smoke and put it down when the nicotine craving is satiated. I know if I vape higher strength nicotine I vape less. I also know what it's like to smoke too much and have never had that feeling vaping.

 

[rolygate]

I don't think there is any way to equate nicotine supply from e-cigs with that from cigarettes as there are too many variables and in any case it eventually becomes a pointless exercise.

Firstly, nicotine obtained from e-cigs is purely that, and nothing else. Obtained from cigarettes it is combined with synergens and other materials that almost certainly affect the way a human body receives it, uses it, reacts to it, metabolizes it, and so on. This can be seen from blood tests on vapers such as the one linked above: none of the figures line up exactly with those obtained from smokers, and some are way off.

We know that the amounts of nicotine obtained are comparable, from the effects experienced and from research such as Dr Eissenberg's most recent tests that showed a 30 or 40ng/ml level which is comparable to that in smokers. But as for the total effect when the other materials in tobacco are considered, or the time needed to obtain X amount of nicotine from a cigarette vs an e-cigarette, it seems to me that trying to equate one with the other - especially if trying to do so by making some sort of statement about the nicotine strength of the liquid needed for an n-pack a day smoker or a smoker of light or strong cigarettes is a waste of time.

The number of variables is almost infinite: whether using a tier 1, 2 or 3 e-cigarette [1]; the strength of the liquid; the type of liquid and how that affects absorption; the possibility that vapor has more buccal and nasal absorption than within the lungs due to the larger particle size; the differing size of the inhaled volume between different e-cig users; the additives present such as menthol that affect the half-life of nicotine; the tolerance and metabolism differences between users, and so on.

I would smoke a cigarette in 5 minutes, and need to vape for 10 -15 minutes @ 36mg to get the same perceived result. For six months I vaped a lot more than I smoked, and used a 5 volt device a lot, but that has settled down to about 50% more and mostly with a standard large-format model. Someone else would most likely give different numbers.

[1] A way of classifying e-cigarettes for various purposes

 

[DC2]

How much nicotine we are getting is a question asked every day in the New Members section.
And it is generally asked by people who are very concerned that they are getting more nicotine than they did smoking cigarettes.

Whether or not that should be a concern to them is another discussion, but suffice to say it is a very common concern.

So to put this conversation in context, here is the response I always give...

Some studies have shown we may be absorbing as little as 10% of the nicotine from vaping.
And some here find flaws in those studies and think they may be getting as much as 40% of the nicotine from vaping.

So, for example...

Let's say you're using 18mg strength liquid, which is 18mg of nicotine per milliliter.
If using 3ml per day of 18mg strength liquid, you would theoretically be getting 54mg per day assuming 100% absorption.

But taking absorption rates into account you will only be getting anywhere from 5.4mg to 21.6mg of nicotine per day.

And that would equal anywhere from about 5 to 43 cigarettes.
Because the amount of nicotine absorbed from real cigarettes is anywhere from 0.5mg to 1.1mg, and some are even more.

So really it all depends on which cigarettes we are talking about, and how much we really absorb from vaping.

So if the answers in this thread continue on their current course, it appears this statement may not be correct...

Some studies have shown we may be absorbing as little as 10% of the nicotine from vaping.

And if that is the case, I will have to stop giving the answer that I always give.

The thing I don't understand is why this 10% number has always been quoted from well before the day I got here.
And why people who say we are getting more nicotine are always disputing that very same number, as if it came from somewhere.

Either it did or it didn't come from somewhere, and I guess that is what I'm trying to find out.

 

[rolygate]

Maybe the 10% was misinterpreted from somewhere. NMs get easily confused, all I'd say is:

-- you have to use an e-cig two or three times as much in order to get the same 'hit' as a cigarette

-- make sure to get some 36mg liquid in among your samples as you may need it if you get strong cravings and you don't want to relapse

-- you'll need a more powerful e-cig as well, if the 36mg liquid doesn't fix it

-- if 36mg liquid and 5 volts doesn't fix it then you are addicted to the WTAs in tobacco as well as nicotine. Use some Snus to get you over the hump or just smoke 1 cig a day until you can let go. That day will come, so don't worry.

 

[swedishfish]

The thread I posted a link to talks about this discrepancy in post #34

That "98% nicotine absorption" figure had been determined for combustion cigarette smoke. In his preliminary Ruyan reports, Laugesen (Health NZ) simply assumed that it would just be the same for e-cig vapor. However, the same study group later reported [thread=15034] new data on blood nicotine levels [/thread] (some links should be somewhere in that thread). Those actual results indicate that uptake of nicotine is less effective than had been previously anticipated. Bottom line, the "98% absorption" figure does not necessarily hold true for vaping.

http://www.e-cigarette-forum.com/fo...lab-results-nicotine-levels-4.html#post493758

 

[BuzzKill]

This is one of those areas that really needs more study and understanding , I hope that now that the Ecig is going to be regulated as a tobacco product that more studies will be done .

My 2 cents.

 

[swedishfish]

Personally, I'm not concerned about how much nicotine I'm getting. I smoked cigs for 20+ years so how concerned can I be? I'm not smoking cigarettes so that's good enough for me. I don't understand why so many smokers, ex-smokers are really preoccupied with nicotine levels vaping when they sure didn't worry about it when they were smoking. If you didn't OD while smoking, it's doubtful you will vaping. But it is a question that's asked frequently.

Maybe it seems too good to be true that you can vape away and not worry when you got so much flack when you were smoking? I guess we were so used to feeling guilty and bad about smoking, it carries into vaping.