There are some quests where you need to jump over lava and stuff like that. However, lava does such a minimal damage, I just run through the lava and don't care.
Same for basically any type of environmental damage I have encounters so far.
For example, in the exploding chests, there is some AoE. I couldn't care less really. Just let em explode.
Is it meant to work like that? Or did some balance change in the past mess this up, and at one point lava was actually deadly?
Funny part is, when a quest NPC even tells you how dangerous the path is, and that you should watch your steps... and then you just swim towards the target right through molten stone