It was supposed to be a normal play day for five friends splashing in a pool in the back yard.

It ended with the group of girls in horrific pain and eventually intensive care in hospital after they all suffered second-degree burns.



The five had spent the day in the pool, splashing around and having fun, The Hanford Sentinel reports.What at first seemed to be overexposure to the sun blossomed into softball-sized blisters and second-degree burns.



Stephanie Ellwanger's girls, Jewels, 12, and Jazmyn, 9, wound up spending several days in an intensive care unit, hooked up to morphine to manage the pain. They stayed in hospital two weeks. Now they're not allowed out in the sun for at least six months. If at all.



But what caused the Ellwanger girls and their three friends - Reyghan, Candy and Bailey - to end up with massive blisters and peeling skin was a mystery.



Doctors were stumped.



Ellwanger, of Hanford, California, later remembered that the girls played with limes from a neighbour's tree, squeezing the fruits and splashing in the juice.



After a Google search and some time trying to convince dubious medical staff, the girls were diagnosed with phytophotodermatitis, described as "a chemical reaction [to the lime juice] that makes bare skin hypersensitive to ultraviolet light."



It’s caused by contact with photosensitizing compounds which occur naturally in some fruits and vegetables — like limes.

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