Cats and PG is a real concern. Not that it is a huge problem, but I have to share that when I started vaping my cat got a bit bent out of shape in the itchiness area. to make a long story short I cut back on the PG and kitty is feeling much better. I will never know for sure is that was the problem. If you don't like cats, you don't care, but if you do It is something to consider.