Plastics are formed in the factory with these tiny beads. They get melted down and formed into the desired shape. The bead form allows them to be pumped through a series of pipes all over the factory.
Googled a source: http://science.howstuffworks.com/plastic5.htm
I'm going to strain out each of the flavours I used in the mix through fine stainless steel mesh tomorrow to pin point it. They must have found there way in there just somehow when the bottles were manufactured.
I work in injection molding, and these pellets seem awfully small. The bottles for flavors are blow molded though, not injection molded. They may have grades of plastic that come in smaller pellets and it may be that I've just never seen them this small. Where I work, this would likely not happen, as the hopper/area that the raw plastic goes into the machine is well away from where the finished parts come out and are packaged. It's certainly a possibility though. If you do find that they come from a specific manufacturer, such as Capellas, I'd be sure to let them know so they can correct the problem with their molder.
Every few mixes I've been doing lately I see one or two of these tiny pellets in the beaker that I need to fish out. Thumb for scale.
I pour straight from the bottle and make sure that the beaker is spotless.
I've checked my PG/VG, Capella 4oz bottles, ecigexpress rebottled flavours etc, whatever I put in closely with just my eyes trying to find the culprit that's contaminating my mix but can't figure out which it is. They're so tiny that they look like air bubbles until I turn on the magnetic stirrer.
Has anyone else run into this and if so what are they from?
Is it possibly burrs from the mixing bar?
I found the culprit to be a large bottle of VG. I'd poured some out into a 250ml clear bottle previously and didn't see any pellets so I moved on to straining all my flavours.
When it was the only thing left through elimination I found a few more pellets at the bottom of the VG.
I contacted the supplier to let them know. It hasn't happened previously with their products so I'm writing it off as a freak accident on a single 1LT bottle of VG.