Just appearing in the online journal PLOS (Public Library of Science) ONE the article Metal and Silicate Particles Including Nanoparticles Are Present in Electronic Cigarette Cartomizer Fluid and Aerosol describes design flaws in a sample of e-cigarettes that might be worth thinking about.
The assaying procedures lie well outside my expertise so I cannot comment on whether they pass muster (when I accessed the article the one commenter, who was familiar with the procedures, voiced some reservations) but the name of one of the authors, Prue Talbot, drew my attention the same way that the name Simon Chapman draws others.
As noted in the conclusion reported below the tested cartomizer aerosol contained contaminants that could be quite dangerous. My argument is not with the finding but I cannot help but think that once again this is a quality control issue that is better handled by consumer product standards than by the health community. As it stands, the shortfall of the tested cartomizers from one source are considered as representative of all sources. Of course, it does not mean that the findings are wrong, but as with the FDA finding it would mean more if a few different models had been tested.
If this has been handled like a consumer product is typically handled we would 1. have been told what brand it was and 2. whether the brand was still on the market (Prue labs have raised fears before using products that were not readily available). If a health warning was the point (as in a food recall) you would mention the brand.
Conclusion (taken from the article)
Cartomizer aerosol from a leading manufacturer of EC contained metals, silicate beads, and nanoparticles. Poor solder joints appear to have contributed to the presence of tin in the aerosol. In cytotoxicity tests, cartomizer fluid containing tin particles inhibited attachment and survival of hPF. Other metals likely came from the wires (copper, nickel, silver) and other metal components used in the cartomizers, while silicate particles appeared to come from the fiberglass wicks. While the outer fibers filtered out many of the tin particles, significant amounts of tin, other metals, and silicate beads escaped into the aerosol and would result in human exposure, in some cases probably greater than a conventional cigarette user would experience. These data should be helpful to individuals who are concerned with the health risks associated with EC use, to health care personnel advising EC users, and to policy makers. The presence of silicate particles and metal elements in EC aerosol may help guide manufacturers in selection of materials for use in EC products and in their quality control procedures.
Its not quite clear as to whether the findings indicated that what they found indicated that the levels of some metals being higher than obtained through smoking might actually translate into measurable health differences. One the other hand this might be exactly the kind of explorations we need to get a handle on the long term effects of vaping using current products. If it really is bad news it does not mean that vaping is a dead end but simply that we need to tighten up quality control or rethink part of the design.
As to these data being helpful I must restate the point that true helpfulness would come with letting us know which brand we should avoid.
Overall, and even though anything associated with Prue Talbot seems to have quite the anti-nicotine and anti-harm reduction agenda, it does seem that this might merit concern. Hence the title of this article (like the boy crying wolf its hard to take Prue seriously even when she might be right). I leave it to those with more experience in this area of science to determine that.
Addendum April 1: Also see Michael Siegel’s comments printed today referring to earlier study of 12 different brands which found that the contaminants in the aerosol were higher in nicotine inhalers than from e-cigarettes.
Addendum April 2: Siegel has a nice followup to this – the gist being that the allowed maximums for nicotine inhalers is at least ten times the amounts that were detected in cartomizer aerosols.