I was researching this subject online last night & was shocked by some of the things i found....
- ALL essential oils are harmful to cats

- scented candles are harmful even when they aren't burning (spores in the air)

- they emit/ contain various substances which are extremely harmful to small pets

- cats skin actually soaks up the junk that comes from these candles, so not only are they breathing it in, it's getting in through their pores

"These issues are significant enough that some websites actually warn against using Glade® or other scented candles around pets. The amount of cabon monoxide, soot and (poor quality) essential oils emitted with the burning are actually lethal to cockatiels and other birds, and are considered toxic to both pets and humans."

Boy, am i glad i looked it up....