MELVILLE, N.Y. (CBSNewYork)CBS2 first reported last January on concerns over artificial turf playing fields being a potential danger to kids.

Now in a CBS2 investigation, Carolyn Gusoff has found these fields may be linked to a growing number of cancer cases in young athletes.

“It’s alarming; you know, scared was the first thought,” said Teddy Shapiro.

Shapiro was talking about little pieces of rubber that can be found–on thousands of artificial turf fields across the country.

It’s called “crumb rubber,” and because it’s made from recycled tires, it is supposed to help cushion an athlete’s fall.

But now, there are concerns it’s making kids sick — kids like Shapiro, who has spent the last decade sliding on these fields. He suffers from a rare form of cancer called osteosarcoma in his pelvis.

Shapiro’s mother, Juli Shapiro, is convinced there is a connection between her son’s condition and the crumb rubber.

“It’s all hard,” Juli Shapiro said.

The Shapiros aren’t the only family with concerns. A Washington soccer coach tracked more than 100 similar cases of cancer in kid athletes across the country.

“I believe that there’s a lot of bad things in crumb rubber,” said coach Amy Griffin.

Experts said the bad things in question include a number of chemicals.

“We know some of these chemicals do cause cancer,” said Dr. Robert Cohen of Northwestern Medicine.

Now, the issue is building steam — from New Jersey to Long Island and even New York City, where there are hundreds of similar fields.

“These are many years that children are playing on this surface, and they’re growing up on this surface, and now, we’re seeing throughout the country these cancer clusters,” said New York City Parks Advocates President Geoffrey Croft.

Croft said he has been petitioning the city to remove the 200-plus crumb rubber fields currently in local parks.

But the Synthetic Turf Council, which represents the companies that make the fields, insists the substance is safe. They cited 60 studies.

One of the studies cited was conducted by the Environmental Protection Agency, which examined four crumb rubber fields in 2009 and found that harmful chemicals were “below levels of concern.”

But Long Island U.S. Rep. Steve Israel (D-N.Y.) said the EPA study is in adequate.

“Common sense tells us that four fields is not an adequate sample in an entire country,” he said.

Israel insisted that the agency should do more testing.

“The only way we’re going to know whether these fields are truly safe or unsafe is for the EPA to get its act together, and update the study, and let the American people know so that they can make their own judgments,” Israel said.

In a statement, the EPA acknowledged its original study was limited, and that more testing needs to be done. But the agency did not commit to doing it.

Many towns across Long Island and New Jersey — as well as New York City — are no longer installing crumb rubber fields.