An 11-year-old Massachusetts girl suffered second- and third-degree burns this month after being exposed to an ingredient in a popular do-it-yourself science project for children.

Siobhan Quinn, of Rockland, is speaking out about the danger after her daughter, Kathleen, was burned making homemade slime, or "gak," that is popular with science-minded children, WCVB in Boston reported. Quinn said she was happy when her daughter decided to do something educational.

"I thought it was great," Quinn told the news station. "I encouraged it, bought all the stuff. And when they were gone, I bought more. She was being a little scientist."

Kathleen’s foray into science came with a painful price. The girl was at a sleepover the weekend of March 18 when she woke up in agonizing pain.

"It felt, like, really hot and tingly," Kathleen told WCVB.

The next day, a weeping Kathleen had ugly and painful blisters all over her fingers. Quinn took her to Shriners Hospital for Children in Boston, where she was diagnosed with the burns.

Doctors told Quinn the burns were the result of prolonged exposure to Borax.

Borax, a detergent and household cleaner, consists of sodium tetraborate, a mineral used in a number of household products. With a low toxicity, Borax is considered relatively safe and is used in recipes for natural cleaners.

It is also one of the main ingredients in multiple recipes for homemade slime or “gak” found online.

Quinn said other mothers have told her that their children have used Borax to make slime “a million times” with no ill effects.

"We made it a million times, too, and nothing happened," Quinn told WCVB.

The concerned mother is not the first to speak out about the dangers of making homemade slime. Rebekha D'Stephano of Manchester, England, told the Manchester Evening News earlier this month that her 10-year-old daughter, Deejay Jemmett, suffered chemical burns to her hands after making "unicorn slime."

Though the recipe Deejay found online called for Borax, it is not easy to find in the United Kingdom because it can cause eye irritation or damage a person’s fertility, the Evening News reported. Deejay used a laundry detergent instead.

"Within 48 hours, her skin had started to peel off," D'Stephano told the newspaper. "From there it got worse."

Deejay’s chemical burns got her a referral to a plastic surgeon, her mother said.

Both mothers have shared their stories in the hopes of making parents more aware of what can happen when making the concoction. D’Stephano said that the videos her daughter found on YouTube showing how to make slime bore no safety warnings.

Quinn said she feels ‘terrible” after watching Kathleen suffer through the burns, which caused her to miss a week of school.

"I feel like the worst mother," she said.

YouTube also has multiple videos on making slime without the use of Borax.