Expandable Water Toys Pose Risk to Children

First Reported Case Reveals the Dangers of Children Swallowing Expandable Water Toy

From the WebMD Archives

Sept. 17, 2012 -- Toy balls that expand in water can be fun and fascinating for kids to watch, but if swallowed they can be downright dangerous. A new report published online in the journal Pediatrics warns parents of the health risks of these toys.

Doctors from the Texas Children's Hospital in Houston describe the first presumed case of an 8-month-old girl who swallowed a gel ball, known as Water Balz. The colorful water-absorbing ball can look like a piece of candy to young children, but the toy is made of a superabsorbent polymer that can grow up to 400 times its original size when submerged. It can become as big as a racquetball.

Although the toy was about the size of a marble when the infant put it in her mouth, the ball expanded inside her digestive system.

About 15 hours after the infant swallowed the ball, her parents took her to the hospital because of stomach problems. But X-rays couldn't detect the toy at that time.

Even so, the baby was admitted to the hospital. Within two days, her belly was swollen and she had symptoms that suggested something was lodged in her bowel. Doctors decided to operate. They found the toy ball was blocking the lowest portion of the small intestine.

The water-absorbent ball had expanded to more than an inch big, a size larger than the small intestine's normal diameter. But surprisingly the toy had remained completely intact -- unaffected by the digestive process.

A Growing Problem

Pediatricians involved in this case wanted to find out how quickly and how much the superabsorbent ball could grow, since the material is increasingly being used in gardening products and in other household items.

So they tested the toy balls by placing them in water and then measuring their size hours and days later. After just two hours, the balls had more than doubled in size.

The balls grew at their quickest rate during the first 12 hours of being dropped into water. Testing also showed that the toy balls had not degraded at all after being placed in water for four days.


Other studies have suggested that most objects accidentally swallowed by children pass through the body on their own, usually without complications. Only rarely is a medical procedure required, and even fewer cases require surgery.

But pediatricians say that expandable toys and products made from water-absorbent materials are different, and their increasing size can become hazardous to children if they swallow them.

At first, the ball was small enough to pass through the opening between the lower end of the stomach and the beginning of the small intestine. But it enlarged as it traveled through the small intestine, where it eventually became stuck.

"This case represents a cautionary warning for both parents and practitioners of the potential dangers of ingesting polymer, water-absorbent balls," the researchers say.

"It also highlights the need for earlier intervention if these superabsorbent toys are accidentally ingested."

WebMD Health News Reviewed by Louise Chang, MD on September 17, 2012



Zamora, I, Pediatrics, published online Sept. 17, 2012.

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