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

[DC2]

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.

That's the answer everyone else gives, and I'll leave that to all of them.


It appears we really don't have a very good idea how much nicotine we are absorbing.
And we also don't have a very good idea, therefore, how much we are exhaling.


This thread might be the best approach to getting down to what is really going on...
http://www.e-cigarette-forum.com/fo...ergs-study-yep-e-cigs-deliver-nicotine-2.html

This post in particular shows where things currently stand...

Study 3 (still ongoing) using experienced vapers who vape ad lib (i.e. as much as they want) has found that a 9mg/ml
Silver Bullet delivered 10 ng/ml plasma nicotine, that a 18 mg/ml Super T Precise delivered 30 ng/ml plasma nicotine, and that a 24 mg/ml Chuck delivered 40 ng/ml plasma nicotine.

And that information is fairly illuminating when combined with this...

There is a table in the NAP, Institute of Medicine book titled "Clearing the Smoke: Assessing the Science Base for Tobacco Harm Reduction" (at page 251 of the online pdf) that blood plasma levels of nicotine are in the 30ng/ml range for "unrestricted smoking". That level is shown to occur in the 2 PM to 10PM time frame, building to that level from 15ng/ml at 8AM. I could not find a definition of "unrestricted smoking" so that may or may not mean chain smoking. In that sampling, the results were obtained from only 8 smokers and the "SE" of the sample (not sure I know what SE is here) took the level to as has high as about 35 ng/ml. But it does suggest that vaping and smoking can produce similar levels in humans.

 

[DC2]

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.

I think a lot of people worry that they will be increasing their addiction (tolerance level) to nicotine.
And I think a lot of people believe that nicotine is a far worse danger than it really is.

I personally believe that nicotine is no more harmful than caffeine, and might actually be quite beneficial.
This is why I personally have no intention of ever lowering my nicotine intake from current (12mg) levels.

And I also believe that nicotine by itself is not nearly as addictive as the general public believes it to be.

 

[Tom09]

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.

Relating to the origin of the alleged 98% and 10% absorbtion numbers:

A) There are three consecutive versions of Laugesen’s 2008 “Ruyan report” floating around on the internet:
1.) Laugesen 2008a: Interim Safety Report on the Ruyan® e-cigarette. Health New Zealand Ltd, 18 January 2008.
2.) Laugesen 2008b: Second Safety Report on the Ruyan® e-cigarette. Health New Zealand Ltd, 9 April 2008.
3.) Laugesen 2008c: Safety Report on the Ruyan® e-cigarette Cartridge and Inhaled Aerosol. Health New Zealand Ltd, 21 October 2008.
These are industry reports (not formally published papers) and have not been thoroughly redacted. In particular, the accurate reference to the “over 98%” absorbtion quote has only been given in Laugesen 2008a. This reference is Feng S. Plunkett SE, Lam K et al. A new method for estimating the retention of selected smoke constituents in the respiratory tract of smokers during cigarette smoking. Inhal Toxicol 2007; 19: 169-79. The referenced paper determined the retention of nicotine from mainstream cigarette smoke in the respiratory tract. Laugesen‘s 2008 reports have been clear that this 98% number was adopted from analog cigarettes, not experimentally dermined for e-cig mist.

B) At that time in 2008, when those early reports had been written, no blood work was available. This changed in spring 2009. First available to this forum was an SRNT conference presentation by Laugesen’s Ruyan team, formally published last year ( Bullen et al. 2010). The authors found that 5 minutes use of a Ruyan V8 (pen style) loaded with 16 mg/ml liquid raised the peak blood nicotine concentration to 1.3 ng/ml. This is a ~ 10% raise when compared to 13.4 ng/ml from a usual cigarette. This result is totally consistent with the data presented in Eissenberg 2010 and Vansickel et al. 2010 (leaving Eissenberg’s vocal misrepresentation aside) and consistent with the “new” findings that more vapor you can raise the blood nicotine levels to those comparing cigarettes.
Do we get a quantitative number for absorbtion out of the published studies? No we don’t - at least not in a direct manner. The ~ 10% heigth of the blood nicotine peak from limited time / limited puff number use of 16-18 mg/ml, as compared to single cigarette, is just that. It does not equal to 10% absorbtion (as this is often falsely stated). Bears no info on absorbtion because a) the investigators did not determine the amount of liquid that has been vaporized (simply missed to put the device on a scale) and b) don’t know the fraction of nicotine which makes it from the liquid into the vapor.

Nonetheless there are some good estimates on this forum. DVap and Exogenesis experimentally tackled the question of the “missing nicotine” in late 2009 (e.g. here and here). As it appears, >90% of the nicotine makes it from the liquid into the vapor. I.e. nicotine is essentially not lost during the heating process. With this fundamental finding and from average liquid consume numbers (under the assumption of nicotine self-titration) the actual absorbtion might end up somewhere in the 30-50% ball park.

 

[OaklandCA]

Nice answer Tom09. i used to use nicotine inhalers marketed as Nicotrol Inhaler which had quite extensive product info sheet
http://www.pfizer.com/files/products/uspi_nicotrol_inhaler.pdf
They have much higher # on the peak level for a regular cigarette 49 ng/mL within 5 minutes. and say the nicotrol inhaler only "concentrations rise slowly to an average of 6 ng/mL" they say elsewhere that 24ng /ml is the avg. for a cigarette smoker while smoking.

the nicotrol is unheated and mainly lands in the mouth--basically like the gum or tablet. It is also very inefficient (converting only 4 mg out of 10mg ) 40% of which they estimate 50% becomes bioavailable.

assuming most of the nicotine in an pv vapor is absorbed at a comparable rate i think your estimate seems pretty solid too

Absorption of nicotine through the buccal mucosa is relatively slow and the high an
rapid rise followed by the decline in nicotine arterial plasma concentrations seen with
cigarette smoking are not achieved with the inhaler. After use of the single inhaler the
arterial nicotine concentrations rise slowly to an average of 6 ng/mL in contrast to those
of a cigarette, which increase rapidly and reach a mean Cmax of approximately 49 ng/mL
within 5 minutes.

 

[DVap]

As far as testing for nicotine metabolites after vaping, I messed with that some time ago. I discussed my results in this blog post.

When looking at nicotine absorption from vaping versus analogs , the analogy is that of "The Tortoise and the Hare"., I discuss an enlightening old study in this blog post. I urge you to read this post closely and understand the implications. I'll be happy to answer any questions. This one seems to get a lot less attention than some of my other posts, yet what it has to say is probably as important as any.

But, haven't you heard? For some of us, it's not just about the nicotine.

 

[OaklandCA]

in reference to the question how much nicotine will i get (or do you get) from that thang? I think a reasonable answer is a little bit less than from a cigarette but it takes a bit longer. As tom09 said for conversational purposes and easy statistic to remember-- it's reasonable to say--"about half as much but if i really work it i can get it up to feeling like about the same level in 10 minutes or so"

as far as the warning level with regard to nicotine itself here's Nicotrol's warning label.


Carcinogenesis, Mutagenesis, Impairment of Fertility
Nicotine itself does not appear to be a carcinogen in laboratory animals. However,
nicotine and its metabolites increased the incidences of tumors in the cheek pouches of
hamsters and forestomach of F344 rats, respectively when given in combination with
tumor-initiators. One study, which could not be replicated, suggested that cotinine, the
primary metabolite of nicotine, may cause lymphoreticular sarcoma in the large intestine
of rats. Neither nicotine nor cotinine was mutagenic in the Ames salmonella test.
Nicotine induced reparable DNA damage in an E. coli test system. Nicotine was shown to
be genotoxic in a test system using Chinese hamster ovary cells. In rats and rabbits,
implantation can be delayed or inhibited by a reduction in DNA synthesis that appears to
be caused by nicotine. Studies have shown a decrease in litter size in rats treated with
nicotine during gestation.

Cardiovascular or Peripheral Vascular Diseases
...Specifically, patients with coronary heart disease (
history of myocardial infarction and/or angina pectoris),
serious cardiac arrhythmias, or vasospastic diseases
(Buerger's disease, Prinzmetal's variant angina and Raynaud’s
phenomena) should be evaluated carefully before nicotine replacement is prescribed.

Accelerated Hypertension
Nicotine therapy constitutes a risk factor for development of malignant hypertension in
patients with accelerated hypertension;

For comparison here's the warnings typically associated with Caffeine.
Caffeine can make sleep disorders in patients with acquired immunodeficiency syndrome (AIDS) worse. Larger doses might cause headache, anxiety, agitation, chest pain, and ringing in the ears.

Large doses may be UNSAFE and can cause irregular heartbeats and even death.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Caffeine is POSSIBLY SAFE in pregnant or breast-feeding women in daily amounts of less than 200 mg. This is about the amount in 1-2 cups of coffee. Consuming larger amounts during pregnancy might increase the chance of miscarriage and other problems. Caffeine passes into breast milk, so nursing mothers should closely monitor caffeine intake to make sure it is on the low side. Caffeine in large amounts is POSSIBLY UNSAFE during breast-feeding. Caffeine can cause sleep disturbances, irritability, and increased bowel activity in breast-fed infants.

Anxiety disorders: Caffeine might make these conditions worse. Use with care.

Bipolar disorder: Too much caffeine might make this condition worse. In one case, a 36-year-old man with controlled bipolar disorder was hospitalized with symptoms of mania after drinking several cans of an energy drink containing caffeine, taurine, inositol, and other ingredients (Red Bull Energy Drink) over a period of 4 days. Use caffeine with care and in low amounts if you have bipolar disorder.

Bleeding disorders: There is concern that caffeine might aggravate bleeding disorders. Use caffeine with care if you have a bleeding disorder.

Heart conditions: Caffeine can cause irregular heartbeat in sensitive people. Use caffeine with caution.

Diabetes: Some research suggests that caffeine may affect the way the body uses sugar and might worsen diabetes. But the effect of caffeinated beverages and herbs has not been studied. If you have diabetes, use caffeine with caution.

Glaucoma: Caffeine increases the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes after drinking caffeinated beverages.

High blood pressure: Consuming caffeine might increase blood pressure in people with high blood pressure. However, this effect might be less in people who use caffeine regularly.

Weak bones (osteoporosis): Caffeine can increase the amount of calcium that is flushed out in the urine. If you have osteoporosis or low bone density, caffeine should be limited to less than 300 mg per day (approximately 2-3 cups of coffee). It’s also a good idea to get extra calcium to make up for the amount that may be lost in the urine. Older women with an inherited disorder that affects the way vitamin D is used should use caffeine with caution. Vitamin D works with calcium to build bones.

 

[harleybluz]

I just read an article, based on 24mg juice, stating we absorb anywhere between 50-80% of nicotine.

 

[DC2]

I just read an article, based on 24mg juice, stating we absorb anywhere between 50-80% of nicotine.

Do have a link? Or perhaps the title of the article?

 

[wdave]

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?

I think a lot of us discount our own experience.

If you are chain vaping then you aren't absorbing much nicotine or you would be dead. Nicotine is a poison.

If your vaping habits are not very close to how your smoking habits were, then you aren't getting enough nicotine.

Sitting around vaping ice cream cones was not exactly the plan I had in mind when I started vaping. But, like many, I allowed people in this forum to influence my choices. Cost me a lot of money and a year of giving up on vaping.

Stick to your original objective. Ecigs are not a smoking cessation device. Get the level of nicotine it takes so your vaping habits closely resemble your smoking habits. Count on acquiring a taste for something that's totally disgusting. You are looking for a replacement for cigarettes and don't let any one tell you that you need to have some other objectives in mind.

HTH,
Dave