Ingestion of pigments capable of producing singlet oxygen with activation by light can produce extreme photosensitivity of skin (see phototoxicity, photosensitivity in humans, photodermatitis, phytophotodermatitis). This is especially a concern in herbivorous animals (see Photosensitivity in animals). Singlet oxygen is the active species in photodynamic therapy. 1270 nm, which is not seen. Nevertheless, at excessive […]