My manager is pregnant and smoking something - is there any scenario where this is safe?

I recently started a new job and the first time I was introduced to one of the managers, she was in the smoking area of the office having some kind of cigarette that looked hand-rolled.

I found out 2 days or so later that she was pregnant and started to doubt myself on whether I had really seen her smoking or not.

Yesterday though I was helping her clean up after training and she pulled out a hard plastic cigarette case and sparked one up. They didn’t look like conventional cigarettes but I didn’t look too hard and I’m fairly certain no amount of smoke inhalation is safe when pregnant. They were white with some kind of plant material inside but I’m unsure if it was tobacco.

I didn’t want to ask any of my coworkers about it because I’m new & don’t fully know all the staff dynamics, but I honestly couldn’t believe what I was seeing.

Is there any kind of explanation for what she’s doing? I’ve been thinking about it a lot and worrying about the baby because of it.