This summer three women from Westport, Conn., urged a nonprofit group in North Haven to test for hazardous materials in synthetic turf that is being placed on playing fields across their state. The results came back positive, showing that hazardous metals in the turf granules leach into water, and that at 140 degrees Fahrenheit (a temperature that synthetic turf can reach during summer), other toxic chemicals are released into the air.

Late last month, in response to the test results, Richard Blumenthal, Connecticut’s attorney general, pledged $200,000 of state funds to study the effects of synthetic turf on people and the environment.

This issue is not confined to Connecticut, which has at least 30 such fields. Across the country, schools and parks are replacing grass playing fields with the synthetic turf. Last year, 850 synthetic turf fields were installed in the United States — more than 150 exist in New Jersey, for example.

Like the women in Westport, a number of residents in several New Jersey towns — including Bernardsville, Flemington, Manalapan and New Providence — want local officials to call off synthetic turf installations. But in the absence of government regulations on the hazards, residents have yet to get any new installations halted.

Although synthetic turf is expensive to install, many municipalities and school districts find it appealing. It’s springier than the old AstroTurf and feels more like natural grass. It doesn’t get chopped up by players’ cleats, and it doesn’t get muddy during a rain, so it allows for more practices and games. In many suburbs, parents are raising private funds to help pay for the new turf.

But despite its appeal, synthetic turf poses serious physical and developmental problems for children. Schools and towns would be wise to avoid it.

For starters, synthetic turf contains highly toxic chemicals. The tiny rubber granules that contribute to the turf’s resiliency are primarily made from recycled tires. Because these granules often lie on the turf’s surface, children and athletes come into frequent contact with them.

Junfeng Zhang, a professor of environmental and occupational health at the University of Medicine and Dentistry of New Jersey, has found that the granules contain worrisome levels of zinc and lead, as well aspolycyclic aromatic hydrocarbons that are likely to be carcinogenic. Some preliminary research by others suggests that it might be difficult for these toxic chemicals in the granules to get into the body through skin contact, ingestion or inhalation, but more research is needed.

Physical health risks aside, children increasingly grow up in sterile, artificial environments. After school, they spend much of their time indoors doing homework, watching television and sitting in front of a computer monitor. Two recent nationwide surveys have found that 6- to 12-year-olds average less than an hour a week in unstructured outdoor play.

When children do get outside, it is usually to play organized sports. Until recently, sports gave children at least some contact with nature. But now, with the widespread installation of synthetic turf fields, even this contact with nature is being reduced.

Children’s alienation from nature is not something to take lightly. A growing body of research suggests that children need contact with greenery for their mental development. Natural settings help them develop their senses and powers of observation. Nature also stimulates children’s creativity; much of their poetry and artwork, for example, is inspired by grass, trees, water, wind, birds and other animals. Furthermore, natural settings have a calming effect on children.

Grass playing fields, of course, expose children to nature to only a limited degree. When it comes to stimulating a child’s senses and imagination, playing fields don’t compare to forests. Still, a grass field can be beneficial to children, especially when adults give them time and opportunity to play in their own ways. After informal games, youngsters often relax on the field, fiddling with blades of grass, weeds and dirt. One 11-year-old told me she likes to toss blades of grass into the air and imagine they are “grass angels.” I’ve also had children tell me how much they like lying on the grass and looking up at the sky.

Lobbyists for the synthetic turf industry claim that it is natural grass that harms the environment because lawn maintenance frequently involves toxic pesticides, herbicides and fertilizers, as well as gas-powered mowers that pollute the air. They have a point, but the solution isn’t to destroy the soil and grass, as synthetic surfaces do, but instead adopt safer methods of grass care.

We’ve already sacrificed too much earth and vegetation to real-estate developments, paved roads and parking lots. We need to preserve the little nature that remains. And we need to do it for our children.

In our increasingly artificial environment, children need much greater experience with all aspects of living nature. Natural grass fields can help.