A carpet freshener nearly killed Livvy. Never bothered Cleo but Livvy finished up at the vets at midnight.
All she did was walk across it once, at around 10pm. Within minutes her feet swelled up, her ladies bits swelled up, and because she tried to clean herself, her face, mouth and throat swelled up. Her face looked like a ball, no definition, and her eyes turned to slits. Her airway closed up and collasped. I'm not making it sound any more dramatic that it was. Her skin was red hot and scarlet. She had a couple of injections, not sure what they were, I was in too much of a state, but within an hour, the swelling had started to go down.
Obviously, I've never touched the stuff again. I don't use spray air fresheners either. We burn candles and open windows a lot.