The newest generation of artificial turf comes with a cushion of recycled tire crumbs and, in some cases, a thick layer of contention.

Industry representatives say the turf - in place at dozens of fields throughout the Philadelphia area - is safe. But some parents are not convinced and have mobilized against it.

In Burlington County, Evesham Township residents last week turned in more than 2,500 signatures aimed at forcing a referendum that would keep synthetic grass off their recreational fields.

"This stuff has ground up rubber tires in it, and it's toxic, and they're letting little children play on it," says Karen Borden, a concerned mother and blogger leading the petition drive. "It's crazy."

In Delaware County, some Radnor residents are rejoicing after the school board recently agreed to toss out plans to install the turf at a new middle school.

The school was designed as a green facility with a grass roof and other planet-saving features and would have looked foolish with a fake field, residents argued at several board meetings.

Across the country, similar scenarios are playing out in town halls and school districts as people debate the safety of the new covering, which industry officials say is being laid atop fields at a rate of 800 a year. In San Carlos, Calif., placard-carrying parents recently marched against a turf project, and New Haven, Conn., residents voted down a multimillion-dollar turf proposal.

AstroTurf, when it was introduced in the the 1960s. was mostly nylon and plastic and was criticized as causing more sports-related injuries because of its hard surface. The more advanced product, which came on the market roughly five years ago, addresses that issue but is raising health and environmental concerns.

Scientists with the nonprofit Environmental and Human Health Inc. in Connecticut released a report last year calling for a moratorium until more studies can be performed.

These scientists say there is evidence the rubber innards of the synthetic turf can emit dust clouds with chemicals that can cause respiratory ailments, endocrine disorders and possibly cancer. The crumbs, which come from a variety of recycled tires, could also cause illness in children through skin contact or ingestion, they say. Some of the elements found in the turf are PCBs, zinc and lead.

"We don't recycle lead, and we don't recycle mercury, and we shouldn't be recycling ground up rubber tires and putting them in parks and playgrounds," said Nancy Alderman, president of the EHHI.

Nonsense, says the Synthetic Turf Council, whose Web site is loaded with links to other reports that find the fears are overblown.

"Synthetic turf is becoming a lot more popular, and of course people are starting to ask questions about its usage, as with anything else having a place in their lives," said Shira Miller, spokesperson for the council. "A lot of people don't realize that a lot of these questions have already been answered, and synthetic turf is perfectly safe."

A handful of companies, including Sprinturf, in Wayne, manufacture the new breed of artificial turf. Miller said no federal or state agency had barred turf fields. The Environmental Protection Agency has found it a good way to recycle tires. Norway considered a ban but examined the issues and found it unwarranted, she said.

In June, the New Jersey Department of Environmental Protection released a report, after reviewing various studies, and found the dangers raised by some groups had not been proven. But the report said further study was needed.

"It's an emerging issue, and we will certainly continue to look at it. We are certainly aware there are concerns about human exposure and environmental impacts from artificial turfs," said Karen Hershey, DEP spokesperson.

The Pennsylvania DEP a few months ago began looking into the safety of turf and the adhesives used to apply it, said spokesman Neil Weaver. He said the agency plans to conduct its own study.

Meanwhile, bills have been introduced in the New York and California legislatures that call for a moratorium until a thorough study can be performed and gaps in the research can be closed.

Borden, an Evesham parent, was among nearly 200 residents who stormed a town meeting in Evesham last month to protest plans to carpet a multiuse field at Memorial Park and a football field at Cherokee Regional High School using a $3.1 million bond issue. Some worried about their children playing on the surface, while others were angry open-space funds were going to be used to purchase plastic and rubber grass instead of preserving land.

Mayor Randy Brown, a former pro football coach and the father of a student athlete, was not fazed by the uproar and said the fears were unfounded.

"It's like cell phones," he said. "There are no documented health problems with synthetic turf."

Turf fields, which cost about $1 million, can be found in about 50 places in the Philadelphia area, including Medford, Mount Laurel, Cherry Hill and Voorhees in South Jersey and West Chester, Upper Dublin and Wissahickon in Pennsylvania.

Brown said every NFL team had either a practice or game field made of turf. He favors the synthetic turf fields because they can be played on all year long and required less maintenance than natural ones.

The local recreation commission warned that without the new turf, it would have to cancel sports-team registrations in the fall. The grass fields require mowing, patching, draining of flooded areas, and other maintenance that could cost up to $25,000 a year per field.

A judge has ruled that open-space funds cannot be used for the Cherokee project, but the mayor said the town would continue to pursue both turf fields.

"For years we have not spent any money on recreational fields or taken care of our children who want to play sports," he said, noting the fields will be used for football, soccer, lacrosse and field hockey.

Borden, who has started a blog at http://votersagainstsyntheticturf.blogspot.com, says any use of turf should be based on popular vote, and she hopes the petition will force the issue to the ballot.

In Radnor, the controversy over turf ended last month in a compromise. Shocked by "the intensity of feelings on the issue," the board created a committee to study what should be done, said Richard McAdams, interim schools superintendent. After several months, the "Save the Grass" committee decided it would be best to have a natural field at the new middle school.

The committee also recommended putting a synthetic field at the high school to address the district's dire need for fields. It already has one such field at the high school.

McAdams said the proposal was still in its infancy. The school district has agreed to pay one-third of the cost, but wants the township and youth organizations who will share the field to pay the rest.

The town has yet to act on the proposal. And, it remains to be seen whether this new turf proposal stirs an uproar in yet another town hall.