Stronger suction is required to smoke "electronic cigarettes" – marketed as tobacco-free nicotine delivery systems – than conventional brands, with possible adverse effects on human health, researchers at the University of California, Riverside report.
The researchers used a smoking machine to compare the smoking properties of eight conventional cigarettes with five e-cigarette brands. They examined the vacuum required to produce smoke (in the case of conventional cigarettes) or aerosol (in the case of e-cigarettes), and compared the density of the smoke/aerosol over time.
The researchers found that except for one brand (Liberty Stix), higher vacuums were required to smoke e-cigarettes than conventional brands.
The researchers also found that in the case of e-cigarettes, the aerosol density dropped after the first ten puffs, requiring still stronger suction thereafter to produce aerosol.
Study results appeared last week in Nicotine and Tobacco Research.
"It is too early to know exactly what effect stronger inhaling and diminishing amounts of aerosol will have on human health, but these factors are likely to lead to compensatory smoking, as has been seen previously with 'light' tobacco cigarettes," said Prue Talbot, a professor of cell biology and the senior author of the research paper.
Talbot's research team examined the following conventional cigarettes: Merit Ultra Lights, Marlboro Ultra Lights, Marlboro Lights, Marlboro Reds, Camel unfiltered, Camel Lights, Camel filtered, and Pall Mall unfiltered cigarettes. In the case of e-cigarettes, the researchers tested the following kits: Liberty Stix, Crown Seven's Hydro Kit, NJOY, Smoking Everywhere's Gold Kit, and a VapCigs starter kit.
"Our work shows that aerosol density decreases as e-cigarettes are used, requiring stronger puffs over time to sustain density," Talbot said. "Manufacturers often claim that e-cigarettes cartridges are equivalent to a certain number of conventional cigarettes. However, this information seems misleading."
Talbot's lab found that while the first ten puffs of an e-cigarette are similar to a conventional cigarette, later puffs were highly variable in aerosol density and do not duplicate smoking of conventional brands. The researchers found that even though one e-cigarette cartridge may smoke for 200 puffs, cartridges do not smoke uniformly for those 200 puffs and therefore do not duplicate nicotine delivery of individual conventional cigarettes.
"Our results show that e-cigarettes smoke very differently than conventional brands," Talbot said. "In preliminary trials, we observed that some brands of e-cigarettes were difficult to smoke possibly because they have relatively small air intake holes. Moreover, the interior of e-cigarettes is dense compared to the relatively porous tobacco-containing cigarettes."
Talbot, who is also the director of the UCR Stem Cell Center, was joined in the research by Anna Trtchounian, the first author of the paper, and Monique Williams of UC Riverside.
The study was supported by the University of California Tobacco-Related Disease Research Program; the University of California Academic Senate; and the Hispanic Serving Institutions-California Cost Reduction and Access Act Science, Technology, Engineering, and Mathematics Pathway Project.
"This paper is the first detailed study showing that greater inhalation pressure is required to smoke e-cigarettes as compared to conventional cigarettes," said Kamlesh Asotra, a research administrator at the University of California Tobacco-Related Disease Research Program. "An important implication is that users must exert greater inhalation pressure and, therefore, it may predictably cause the aerosol to reach deeper tissue in the user's lungs. As in the case of conventional harm reduction cigarettes with lower nicotine content, users of e-cigarettes may also need to smoke greater number of puffs to receive sufficient amount of nicotine to satisfy their craving.
"Based on the results of this paper, not only do users become more aware of the vapor characteristics and smoking properties of e-cigarettes but also manufacturers of e-cigarettes will take notice of the functional inconsistencies of their products," he said.
About electronic cigarettes:
E-cigarettes are marketed as a relatively new type of tobacco-free nicotine delivery device, consisting of a battery, a charger, a power cord, an atomizer, and a cartridge containing nicotine and propylene glycol.
When a smoker draws air through an e-cigarette, an airflow sensor activates the battery that turns the tip of the cigarette red to simulate smoking and heats the atomizer to vaporize the propylene glycol and nicotine. Upon inhalation, the aerosol vapor delivers a dose of nicotine into the lungs of the smoker, after which, residual aerosol is exhaled into the environment.
While produced mainly in China, e-cigarette use has rapidly proliferated worldwide. E-cigarettes do not burn tobacco and therefore do not deliver the numerous chemicals and toxicants found in conventional cigarette smoke.
To date, little has been published in the scientific literature about the health benefits and risks of e-cigarettes.
About the smoking machine:
The smoking machine consists of a puffer box connected via tubing to a peristaltic pump. The line between the puffer box and the pump contain two untapered T connectors. The connector closest to the puffer box holds the conventional or electronic cigarette. The second connector is attached to an upright U-shaped water manometer built at UC Riverside. The manometer measures the vacuum in the line drawing a puff from each cigarette.
The University of California, Riverside (www.ucr.edu) is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment of about 18,000 is expected to grow to 21,000 students by 2020. The campus is planning a medical school and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Graduate Center. The campus has an annual statewide economic impact of more than $1 billion.
A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. To learn more, call (951) UCR-NEWS.
Iqbal Pittalwala | EurekAlert!
Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)
The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research