Bergamot essential oil and furanocoumarins. The main compounds in the oil are limonene, linalyl acetate, linalool, γ-terpinene and β-pinene, and in smaller quantities geranial and β-bisabolene. The main non-volatile compounds are coumarins (citropten, 5-geranyloxy-7-methoxycoumarin) and furanocoumarins (bergapten, bergamottin). The bergamot essential oil is particularly subject to adulteration being an essential oil produced in relatively small quantities. Generally adulteration is to "cut" the oil, i.e. adding distilled essences of poor quality and low cost, for example of bitter orange and bergamot mint and/or mixtures of terpenes, natural or synthetic, or "reconstruct" the essence from synthetic chemicals, coloring it with chlorophyll. Worldwide, each year, around
Bergamot orange for grapefruit–drug interactions in which the consumption of the juice affects the metabolism of a variety of pharmaceutical drugs. Used in cosmetics and perfume products, bergamot may cause skin irritation. In the past, psoralen extracted from bergamot oil has been used in tanning accelerators and sunscreens. These substances have been known to be photocarcinogenic since 1959, but they were only banned from sunscreens in 1995. These photocarcinogenic substances were banned years after they had caused many cases of malignant melanoma and deaths. As of 2017, clinical research conducted on bergamot oil has been of poor quality, with no conclusions possible