A bartender's hand after squeezing limes and spending a day on the beach.Justin Fehntrich

Last month, on a hot Saturday afternoon, Justin Fehntrich showed up to bartend at a swanky Fire Island Pines estate. The event he was working, a fundraiser for an LGBT-advocacy nonprofit, had about 100 guests and two other bartenders. He got the bar with the best view: the one in the sun, wedged between the sprawling, sparkling pool and the breezy ocean shore.

Just as he and the other bartenders were about to prep their stations, a representative from the event’s official liquor sponsor asked if they wouldn’t mind squeezing four bags of limes. Justin offered to drive to the supermarket and buy a bottle of juice, but the rep insisted on fresh, so Justin and another bartender sliced and squeezed about 100 limes into pitchers for cocktails.

“That was a huge mistake,” says Justin, who’s a friend of mine and a student at Stony Brook University. A few days later, he found himself in the hospital—with second-degree burns.

On his way to the hospital, Justin posted a photo on Facebook of his hand, which was red, swollen, and dotted with thick, bubbly, yellow, fluid-filled blisters. “Poison oak?” he wrote. But it looked as if someone had cruelly poured scalding hot water over the top of his hand, not as if he’d accidentally brushed up against a noxious green vine. Shortly after, he added a picture of his hand wrapped in a thick glove of gauze and gingerly resting on a white-and-blue antimicrobial pillow.  “Update,” he wrote. “It’s not poison oak, it’s phytophotodermatitis, or ‘margarita burn’….”  

Courtesy of Justin Fehntrich

Yep, margarita burn. As Justin soon learned, the juice and oil of limes contain chemicals called photosensitizers, which make human skin extra-sensitive to sunlight. When an affected spot is overexposed, it burns.

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.

“At the very least we should make it an agenda item at our local chapter meetings,” he contends, noting that going forward he plans on making sure the condition becomes a regular part of talks.

In hindsight, Justin says it certainly would have been helpful to have been informed about phytophotodermatitis in his bartending training. If he knew the signs and symptoms, he says, he would have refused to squeeze the limes that sunny June afternoon.  

Courtesy of Justin Fehntrich

After leaving the hospital, Justin walked around for about three weeks with his hand buried in gauze, until he no longer needed to clean, treat, and dress his hand every morning. He had to take a break from bartending (and surfing). Now he’s waiting for the tight, very pink, new skin on his hand to grow additional layers and start looking and feeling more normal.

“The funniest part of this whole thing is that I didn’t even use the lime juice I squeezed,” says Justin. “Basically, the fruits of my donated labor ended up burning me in the end.”

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