Phototoxic or Photosensitising oils are essential oils which can react with the UV rays in sunlight and cause a reaction on the skin. They make the skin more susceptible to UV radiation and can cause redness, irritation, skin cell damage and can also increase the risk of skin cancer. It is therefore important that these essential oils are avoided when making sun screen, insect repellent, or a body lotion that is going to be applied to the skin before being exposed to the sunlight.
Here is a list of essential oils that are considered photosensitising:
Bergamot (unless you use FCF Bergamot which is free from Bergaptene)
Cold pressed Lemon
Cold pressed Bitter Orange
Cold pressed Grapefruit
Cold pressed Lime