Clean techniques for refilling?

[CES]

I’ve noticed reports here that a subset of users are having symptoms related to vaping when they didn’t previously…in some cases it seems to be related to VG or PG or a particular flavoring, in some cases there isn’t a specific identifiable trigger. I’m wondering if anyone has looked the risks of contamination related to refilling cartridges or cartomizers at home. One of the clear and real concerns that people have identified is whether or not the original manufacturing facilities use clean or sterile techniques in manufacturing and distributing e-liquids. Makes sense, I'm vaping in part because I want to cut down on the amount of foreign junk/toxins I put in my lungs. But what about once we open the e-liquids, carts or cartomizers? Are there differences related to dripping vs refilling? Does anyone use sterile techniques to refill? Is it necessary? Should some guidelines be developed to help decrease the possibility of contaminating e-liquids with bacteria or chemicals? Simple stuff: clean hands, clean work space, distilled vs tap water, ethanol vs isopropyl….