Purity of E-Liquid, Glass Bottle's Plastic Cap Threads Shaving, Dust? Anyone Else?

[BRYAN69]

I use regular black bulb dropper glass bottles that most companies use , in fact i got them from most companies, i make my own juice and have bought others of course, but what i noticed is that almost each bottle after some use and no matter what juice you got in it, i have tested it even with plain water,so it's not like juice doing it but after some use i guess the treading on the cap starts to fall apart slowly and like small pepper size bits and tiny dust like black pieces of plastic can be found around the glass bottle's threads and if u look very carefully in a e liquid. if i see them and i see very tiny ones that are like specs of dust, so small when i put that drop on my finger most people have to really zoom in and focus to see it, little easier to spot in liquid, anyhow those are the ones i spot, i wonder if there are even smaller ones that i cant even see, and does anyone have a solution for this so i/we don't vape on plastic. thanks any help is appreciated.

one solution i found is to drip only on cotton so if there is any they would get stuck on cotton and only e liquid would get all the way to coils and burn, but wish i had a better solution so can drip freely over the coils.

another thing i noticed is that some dropper bottles had numeral markings on the glass dropper/pipette well some liquids completely dissolved/removed those markings.

does anyone know where to get some really good quality glass bottles, without painted markings and plastic caps that fall apart over time, something truly suited for e liquid?