Lime oil comes in two versions that are not interchangeable, and the label rarely says which. Cold-pressed peel oil carries furanocoumarins and burns skin in sunlight.^[2] Steam-distilled lime has none of them and is safe on skin, but smells flatter and less zesty. Both are roughly two fifths limonene, with citral and pinene giving the sharp green bite.^[1] In lab tests the oil held back bacteria and mopped up unstable molecules.^[1]