So, this e-cigarette thing & vaping nicotine liquid. Contributor?

I know you must be wondering a few things.  What is an e-cigarette?  What is vaping? Nicotine liquid?  And why in the world did she choose a pina colada as the image for this post?

In order:  An alternative to smoking traditional cigarettes (or "analogs" as they're commonly referred to within the "vaping" community), an electronic cigarette, or e-cig, is actually a bit like a small fog machine.  It heats liquid - either with or without nicotine - to a vapor, which can be inhaled and exhaled like cigarette smoke.  We "vapers" refer to that act as "vaping."

Why the pina colada? Because unlike traditional cigarettes, liquid nicotine comes in many tasty flavors - as many as you could possibly imagine.  If you can think it, someone has probably added FlavourArt liquid flavoring - such as would be used in the commercial beverage industry - to a nicotine and vegetable glycerine base.  My favorite for several months was, you guessed it, pina colada.

The trouble is, I've learned two things since I first picked up an e-cig (and put down the cigarettes the same day), one is that while the flavorings are on the generally recognized as safe (GRAS) list for ingestion, several are definitely not safe for warming to a vapor and inhaling.  In particular, one compound called diacetyl, a diketone, which produces a buttery or creamy flavor and was very popular in several "nicotine juice" flavoring concoctions is also known to cause a disease called Bronchiolitis Obliterans, aka "popcorn lung."  Essentially, the warmed vapor is known to cause irreversible lung damage.  But vendors still used it, and buyers still bought it.  There is/was quite a bit of debate over whether the compound was safe in the minuscule amounts that e-cig users were probably receiving.  

Which would seem to have nothing to do with anything.  Except, after six months of vaping, I came down with my transverse myelitis lesion.  And in my research came across this article on b12 deficiency-related paresthesia and myelopathy (which may mimic or lead to TM-like lesions and was curable with b12 injections):  http://www.mayoclinicproceedings.com/content/77/3/291.full.pdf 

In short, what caught my eye was that hexanedione is listed as a known neurological toxin.  Hexanedione is in the same compound description as diacetyl, they are both diketones - it is also used as a flavoring which can produce a buttery or creamy taste.

So it begged the question - was there a chance that my TM was not actually idiopathic, but had a definable cause, right in my hand?  No flavoring vendor that I am aware of used hexanedione specifically.  But 2,3 pentanedione was used, and as you may have guessed by that "dione" suffix, is another diketone.  It would seem that direct inhalation of diketones wouldn't be the best idea under any circumstances.

Additionally, I came across information that nicotine inhibits b12 absorption, and wondered if in fact there is something about the way that e-cig users absorb nicotine that further interferes with b12 absorption.

And as if this isn't long and "what if?" enough... The e-cig itself uses what is referred to as an atomizer (or alternately, cartomizer) to actually heat the liquid.  And how are the atomizer parts constructed?  With solder, of course.  Everyone recognizes that using lead solder would be a very bad idea, indeed, and instead a common replacement is silver/tin based solder.  And you know what is also a neurotoxin?  Heavy metal poisoning, such as by silver.

Thankfully some "cartomizers" are coming out now that are solder-free, so perhaps that is at least one less thing to worry about.  But that's the problem with an idiopathic diagnosis - we just don't know what caused it, and all I can do is continue to guess.

In short, I feel as if I might be something of the canary in a coal mine, and am simply the first of others who might encounter neurological damage due to their desire to reduce the harm caused by cigarette smoking.