Candle, Candle Burning Bright
Those scented candles we humans love so much may be the most likely to cause problems for our cats.
First, think about the scent itself. While a peppermint-, gingerbread- or pine-scented room smells wonderful to us, it can be overwhelming to an animal who's much smaller than we are and has a much more acute sense of smell. And a burning candle can disguise the familiar scents that make a cat's house feel like home.
But discomfort isn't the only problem cats can have with scented candles. Many candles contain essential oils, which can be toxic to cats. Since their skin is much thinner than ours is, these concentrated substances are absorbed into the bloodstream more quickly. And since cats can't efficiently metabolize the compounds in most essential oils, they can cause toxic build-up in the cats' bodies.