Vaping

Does anyone here actually know what’s in second hand vape steam/smoke? (whatever it is) I don’t vape- I never have and never will- but a lot of my family does and I don’t like the idea of breathing in their second hand chemicals with a developing fetus in me. I don’t want to avoid our frequent family parties but I know they won’t do it outside when it’s cold so it may come down to me just not going. I can’t really find good info online so I thought I’d ask here. Thanks