All of the citrus oils, including lemon, lime, tangerine, grapefruit, mandarin, and bergamot, are a big problem for all skin types. Also extremely problematic are mint oils such as peppermint, wintergreen, pennyroyal, and balm mint. In a similar vein, avoid camphor oil, which is a potent irritant. Despite their reputation for being soothing (and they are if you inhale them rather than put them on your skin), flower-derived oils like lavender and rose are also problematic. Ironically, both of these oils contain skin-calming substances, but those are present along with the problematic fragrant substances—you can’t get one without the other.