eLiquid gets dark in the cartridge. Is this the tin found in vapor news talk about?

[jsoldi]

I use an eGo-C. I see that my eliquid gets darker in the cartridge as I vape-refill-vape-refill... Here is a pic. The one on the right is a cartridge I cleaned before refilling. The one on the left I just kept refilling without cleaning it. I wonder if this darker color is because of tin or some other metallic particles that come off of the atomizer that will end up destroying my lungs? Any idea?

Seems that this is the original study. It is weird the article is from 2013 but I never saw it in the news until a few days ago. Also, the news sites I've seen it in don't seem very trustworthy, but anyway, there seem to exist a real study.

Oh and also, not sure if this is related, sometimes, apparently for no reason, the vapor will start tasting like burnt metal, kinda the same flavor you'd get when you vape off of an empty cartridge. And when I say for no reason, I mean the cartridge is not empty when this happen as I always refill it before all liquid is gone. Any idea what may cause this?

 

[Eranda13]

If you're using a sweet juice the heat could be carmelizing the sugars in the juice and turning it dark.

You could get burnt hits if your juice isn't getting to the coil properly.

Also if I remember correctly the only one that has tin used solder for the electrical connections and was made in China, and was the only brand made that way. I don't believe what you're vaping has any solder at all, so it couldn't contain tin.

 

[Christopherja]

I can't comment on the nano-particles, though PLOS ONE is a reputable journal...

To be honest, juice darkening is a common phenomenon in most atomiser-systems. There's nothing to worry about, per se, about the vapour. As for your metal tastes, that sounds like a wicking issue - a "dry hit". The Ego-C atomisers aren't fantastic - so they might be having issues wicking. Vaping a thinner juice might help, or else refraining from chain-vaping. Or, of course, moving on to another atomiser-system.

Hope this helps

 

[yzer]

The darkening is caused by reheating the nicotine in your juice. As nicotine is heated it oxides and produces a number of compounds including the primary byproduct of nicotine oxidation, cotinine. The cotinine accumulates the longer you keep re-using the old liquid. I experience the same effect with cartomizers in a carto tank set-up. As I refill the tank over a week or so the juice keeps getting darker. I replace cartos after I vape about 20 ml of liquid through them and wash out the tank for this reason.

The nicotine in a juice will oxidize on it's own even if it isn't heated. That's why the juices darken or yellow with age.