Bergamot and Phytophotodermatitis
Bergamot contains bergaptene that makes people photosensitive, a condition called phytophotodermatitis that can result in severe sunburns and blistering on the areas where juice has made skin contact. Bergapten-free bergamot essential oil or synthetics are now used in perfumery. [link]
Photosensitivity can also be caused by other citrus fruits, celery, dill, parsnips, and parsley.
Be cautious when using/squeezing/juicing citrus in outdoor bars/settings to avoid getting citrus on your skin as well as on customers. Consider squeezing juice indoors, and washing your hands/areas of skin contact well after handling citrus juices during/before going into the sun.
Bergamot and drug interactions
"Bergamot is also a source of bergamottin which, along with the chemically related compound 6',7'-dihydroxybergamottin, is believed to be responsible for grapefruit–drug interactions in which the consumption of the juice affects the metabolism of a variety of pharmaceutical drugs." [link]
note: These links have unpleasant images.
"How lime juice can lead to severe burns — and what to do about it" Today.com [link]
"This Guy’s Blistering Burns Show Why You Shouldn’t Handle Some Fruits Outside" MensHealth.com [link]