Levitas, such information is not all that hard to find out with a little more digging.
Did you click the links on that scary "research" page you found? They lead to email sign-up pages or advertising. If this is the only source of your worry, I think you can stop. That page is pure Internet Marketing 101: controversial subject and unsubstantiated claims, designed to raise anxiety and get you to click for more information. Anxious people buy things to alleviate anxiety.
Read it again. Is anything much quantified in that article? No. They say "large" amounts of such chemicals can be harmful, then raise concerns about two different glycol chemicals, but refer to them using "and" instead of being specific. If they know so much, why don't they just state the specs? Notice that they don't, for PG. Could that be because (according to Wikipedia) "The industrial norm is to replace ethylene glycol with propylene glycol when safer properties are desired." But this scary website doesn't bother to distinguish between the two. They make claims about toxicity without actual details, thus painting PG with the same brush as EG, when in fact they are different.
In an attempt to add legitimacy to their shoddy "research" however, they credit an official-looking authority:
"Source: Information reproduced courtesy of
Agency for Toxic Substances and Disease Registry
Division of Toxicology"
Is there any such outfit? Yes, they're under the auspices of the CDC. I went to
their website and searched for propylene glycol. Check this out:
Ethylene Glycol and Propylene Glycol Toxicity: What is Propylene Glycol | ATSDR - Environmental Medicine & Environmental Health Education - CSEM - there it says specifically that "Unlike ethylene glycol, propylene glycol does not produce nephrotoxicity in humans." That means it does NOT cause kidney damage. It also says, "FDA considers an average daily dietary intake of 23 mg/kg of body weight to be safe for persons 2-65 years of age (Agency for Toxic Substances and Disease Registry 1997)."
I did some more researching for math in terms of liquid, found some conversion calculators, and if I did the math right - that translates to about 1/3 of a gallon for a 110 pound woman.
Daily. Not that I trust the FDA, but that's a LOT of PG. And you are worried about 3ml?
Research is good, but anybody can claim anything on the internet. Most people do not take the time to verify sources, so many "research articles" cite sources that actually say something completely different than what the article suggests, as in this instance.
It's good to be concerned about the probably-benign chemicals we're using in a way that no studies have contemplated. Some people do have allergic reactions, and to all kinds of things; we live in a highly chemicalized world, especially compared to 50 years ago. That's why I eat a lot of organic, locally-grown food and shun Big Pharma and Big Agra as much as possible.
But I'm really not that concerned about possible long-term effects of vaping being harmful, even after weeks of intensive research (confession: that was mostly on ECF, which has an obvious bias, but a lot of outside reading too). I've been exposed to PG and VG all my life as an American, without harm - it's in everything. I don't intend to be vaping forever, but while I choose to, I'm not going to worry about some one-page website trying to get me all worked up with incomplete, inaccurate allegations that are easily countered with a little further investigation. ESPECIALLY when that website's claims are refuted by the very source it cites!!
In fact, I'm probably harming my liver more by drinking the beer I'm about to open. Cheers, everybody! Vape on!