According to the Centers for Disease Control and Prevention (CDC), there have now been 153 reported cases of severe, acute lung disease caused by "vaping" across 19 states. Tragically, one of these cases resulted in a death. Most of the cases are occurring among youth or young adults. The acute disease appears to be taking the form of lipoid pnemonia, acute respiratory distress syndrome, and/or chemical pneumonitis.
Physicians, health departments, and the CDC have almost uniformly informed the public that these cases are caused by "vaping" and have advised youth and young adults to avoid using "e-cigarettes."
The Rest of the Story
The advice from health agencies, including the CDC, to avoid using "e-cigarettes" is irresponsible. This is such a broad category of products that it doesn't really give people any guidance whatsoever in terms of what to avoid. There are millions of people who are vaping nicotine-containing e-liquids and it would not be prudent for these millions of people to return to smoking in order to avoid the risk of this "unknown" and "mysterious" medical condition. Moreover, with such vague advice, no one is likely to change their behavior because they are not being warned about any specific, identifiable risk.
The truth is that in every case so far in which a specific e-liquid has been identified, that product has been a THC-containing e-liquid, typically purchased off the street and often in open cartridges such that they could contain a contaminant or other drug. In at least some of the cases, the use of a THC oil, such as butane hash oil, has been implicated. In January of this year, there was a published case report of a severe, acute respiratory illness attributable to the use of butane hash oil. Apparently, all 21 cases in California were attributed to vaping of marijuana with all the THC e-liquids being purchased on the street.
Since lipoid pneumonia is caused by oil inhalation, it seems pretty clear that those cases diagnosed as lipoid pneumonia are being caused by the use of e-liquids that are oil-based, not alcohol-based. Most nicotine-containing e-liquids are alcohol-based, meaning that they contain as excipients some combination of propylene glycol and glycerin. These products do not pose a risk of lipoid pneumonia. There are some nicotine-containing e-liquids that are oil-based, and these should absolutely be avoided.
Although we do not have a single common link between all the reported cases, there are useful recommendations that the CDC could be giving. At a minimum, they should be telling the public not to vape THC oils, including butane hash oil. Second, they should be telling people not to use any oil-based vaping e-liquid product. Third, they should be telling people not to use any e-liquid unless you know what is in it -- that is, do not buy products off-the-street and stick to products being sold at retail stores, especially closed cartridges where there is no risk of contamination or the presence of unknown drugs.
These would actually be useful recommendations that could possibly help prevent further cases. Instead, the CDC and other health groups are providing such generalized and vague advice that it is essentially meaningless.
Sadly, the failure of CDC and other health agencies to provide appropriate recommendations is putting kids' lives at risk. Since there has been no admonition to avoid the use of THC oils, kids are going to continue to use these products. This is why the CDC's recommendations are irresponsible.
The question is: why are the CDC and other health groups being so broad in their statements, warning broadly against "vaping" or using "e-cigarettes" but failing to warn against the use of THC oil?
The answer, I believe, is that these organizations have such a pre-conceived conclusion that vaping is hazardous and such a bias against the use of e-cigarettes for smoking cessation that they are hoping to be able to attribute these cases to traditional nicotine vaping.
By no means are we in a position currently to be able to conclude that vaping THC oils or other oil-based e-liquids is solely responsible for the observed cases nor are we sure that street-purchased products are solely to blame. However, I think we know enough to be able to offer a specific recommendation that people not use these products. That CDC has failed to do this is irresponsible, putting lives at risk, and demonstrating the agency's bias in its views of the science around smoking and vaping.