E-cig News

This past April, The Society for Research on Tobacco and Nicotine met in Dublin for their annual conference. Tickets into the event were costly, priced around $500. Very little information is available as to what was discussed but one notable attendee for electronic cigarette users was Dr. Murray Laugesen of Health New Zeland.

Dr. Laugesen has been involved with tests for the Ruyan brand electronic cigarette for over a year now and was kind enough to make available the poster which he displayed at the conference which outlined the results of his Ruayn e-cigarette bench-top tests (PDF)

Dr. Laugesen has described the Ruayn e-cigarette which he uses in his trials as being rated several orders of magnitude (100 to 1000 times) less dangerous than smoking tobacco cigarettes.

Nicotine Not Absorbed By The Lung
What I had not heard him acknowledge before though, is that he advises that the nicotine from an e-cigarette is not absorbed from the lung, but from the upper airways. This is what some members of the electronic cigarette community have already suspected. Cigar smoke acts in the same way due to it being alkaline in nature, different from cigarette smoke which is acidic and is designed to cause the nicotine to be absorbed into the body from the lungs. This is also the reason why cigar smoke is harsh when inhaled while cigarette smoke is smooth.

But Dr. Laugesen says that the reason nicotine from an e-cig is absorbed from the upper airways is that the nicotine dose and particle size are too small to ensure deposition in the alveoli or bronchioles within the lung.

Nicotine Absorption Rate
Dr. Laugesen describes how he found that an e-cigarette user will need to take more puffs more often for the body to absorb the same amount of nicotine as cigarette smoker would with a cigarette. Deeper puffs confer no advantage.

"Six puffs every 5 minutes would deliver the same dose of nicotine delivered by shallow inhaling from one tobacco cigarette every hour". That means 72 puffs of an electronic will give a user the same amount of nicotine as they would get from shallow inhaling one cigarette. He used 16mg e-liquid in his tests (what is commonly called 'High') to get these figures.

He says this would not achieve the high immediate nicotine boost which many smokers crave. This could be the reason why some e-cig users think that there is something lacking. He says a nicotine overdose is unlikely, even though nicotine delivery may vary between brands.

Clinial Trial with Human Paricipants
Another PDF available on the Health New Zeland website describes a clinical trial undertaken by the scientists at the University of Auckland Clinical Trials Research Unit of which Dr. Laugesen was co author. This trial used 40 participants, all smokers from his home country of New Zeland.

The aim of this trial is described as being to measure the effects of the Ruyan e-cigarette on craving relief and withdrawal and explore its acceptability and pharmacokinetic properties in comparison to an electronic cigarette which contained no nicotine, a Nicorette® nicotine inhalator and also factory made cigarettes.

Method
Their method was to randomise each of the forty participants to a day’s use of each of the products with 3-days smoking their usual cigarette in between.

'After overnight abstinence, measures were taken before and for one hour after first use, and again after 8 hours further use on each day. The primary outcome was craving relief rated on a 0-10 visual analogue scale measured as ‘area under the curve’.

Secondary outcomes included withdrawal symptoms and acceptability. Nine of the participants also had serum nicotine levels measured over one hour after first use of each product.'

Results
Over 60 minutes, participants using the 16mg Electronic cigarette experienced significantly less craving than when using the e-cig which contained no nicotine. Cigarette use reduced craving more than the 16mg electronic cigarette and and Nicorette® inhalator over the same period (not surprisingly).

Compared to the no-nicotine e-cig and the Nicorette® inhalator, the 16mg e-cig rated lowest for irritability, restlessness, poor concentration and need for a cigarette but these differences were not significant. The 16mg e-cig was described as being was well tolerated, acceptable and had fewer adverse effects than the inhalator.

The 16mg EC delivered nicotine more rapidly than Nicorette® inhalator but not as rapidly as cigarettes, which also gave the highest amount of nicotine, almost ten-fold that of the 16mg E-cigarette and Nicorette inhalator.

The most commonly reported adverse affect among partipants in the trial was throat irritation.: 23% of the participants saying that they experienced it while using the non-nicotine e-cig, 33% for the 16mg e-cig and a huge 58% of particpants saying they experienced throat irritation while using the nicorette inhalator. Other differences in adverse effects reported between the products were small and not significant.

Conclusion
Dr. Laugesen's conclusion was that the Ruyan e-cigarette showed promise as a device that might aid cessation but that trials to assess long-term cessation outcome and safety are needed.