There is a good bit of information online and in pet books about not using essential oils with cats or even diffusing essential oils as aromatherapy in homes with cats. The concern is due to the chemical component known as phenols. Products that are not pure essential oils often contain synthetic phenols, but even some pure oils, like the Nature's Sunshine's oils, contain naturally-occurring phenols as part of their chemical structure. Phenols are water soluble and evaporate more quickly than oils that do not contain phenols. Because of their strength they can be irritating to the skin and possibly damaging to the liver. It is important to use a pure essential oil, rather than one with synthetic ingredients. Examples essential oils with natural phenols are: Bay, Oregano, Clove, Thyme, Cinnamon, Savory, and Tarragon. This is not an inclusive list.
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