Some other fruits and plants, including wild carrots and parsnip, also contain photosensitizers. According to the Mayo Clinic, bartenders, chefs, and other people who routinely handle citrus fruits are among those most at risk of developing phytophotodermatitis. Burns mostly happen on people’s hands, but they also can pop up on arms and legs, where citrus juice has splattered or citrus-based drinks have splashed or dripped.

“The head nurse in the burn unit told me I had a classic case,” Justin told me. His idyllic work station in the estate’s backyard—“basically on the beach,” in his words—had kept him under hours of direct sunlight. Another bartender he worked with also suffered phytophotodermatitis, but not as severely, because she was assigned a bar in the shade.

Margarita burn is treated just like any other burn, says Jeremy Goverman, a burn expert at Massachusetts General Hospital and professor at Harvard Medical School. “Moisturizer and sunscreen for first-degree burns, and for second-degree burns, we drain the blisters then apply bacitracin or a triple antibiotic, nonstick dressing and gauze once a day until the burns are healed.”

But treatment can only happen if phytophotodermatitis is recognized in the first place—which, according to Goverman, isn’t always likely. In Justin’s case, it took seeing an experienced clinician in a hospital burn unit to arrive at his diagnosis, as the attending doctors in the hospital’s intake unit had no idea what was going on. Goverman has only seen three cases of phytophotodermatitis in his career—all of which could have been mistaken for other skin conditions—and has heard of others where doctors initially suspected their patients’ burns were poison ivy or oak, or some other kind of skin irritation.

“In a sense, it’s a different type of ‘lime disease,’ in that phytophotodermatitis is often misdiagnosed; it’s that rare,” he says. Phytophotodermatitis is so unusual that its frequency hasn’t been well established in the United States.

Despite its rarity, Jason Foust, the Midwest regional vice president of the U.S. Bartenders’ Guild, thinks that margarita burn needs to be recognized as a very real hazard among bartenders. “Today there is a big commitment to using fresh juices, and that means squeezing more limes so there is more risk,” he says. “So, it should be a bigger part of discussions.”

The U.S. Bartenders’ Guild regularly holds national and local educational events for its members, in addition to providing them with online resources on bartender health and safety. These include workshops on product knowledge, bartending skills, career development, and wellness. Foust, who advises bartenders to wear gloves, regularly wash their hands, and avoid working in direct sunlight when handling citrus fruits, says adding phytophotodermatitis to the educational agenda of U.S. Bartenders’ Guild just makes sense.