Lacewood is one that came up in conversation here early - it’s gorgeous but even cutting it, let alone burning, can release irritants for many. Some should be obvious (don’t use poison ivy/oak/sumac leaves in anything), others are more subtle.
This is a crazy complete list - but not everything that is an irritant will irritate you, but generally stay away from the 5 
woods!
You’ll note Myrtle is on this list, but way down at 2 s, so with good ventilation…