There is even a product (seen here ) of a hollowed ceramic log and refillable granules that create both the wood burning smell AND the crackling sound.
... and the cancer-provoking microscopic particles! For only ten times the price!
More seriously, I'll look up if incense has the same problems. I don't see why it wouldn't.
Some thoughts- Even if incense also creates cancer-provoking particles, I would guess that it creates much fewer, since you are only burning say 2 grams of material, versus a couple of large logs .
Also, I would guess that oil-based incense and candles are likely to be safer (Oil-based incense is what I was thinking of when I wrote the grandparent)
Both of these thoughts though, are subject to change if/when provided any contrary research on the matter.
Sam Harris, in his recent article called The Fireplace Delusion, tries to make you feel what it's like to react to a cached belief being irreparably destroyed. Just incase you forgot what your apostasy (if you had one, of course) was like in its early stages.
What are some of the Fireplace Delusions you've come across in your days?
EDIT: WOODSMOKE HEALTH EFFECTS