The federal Centers for Disease Control has recommended that some artificial turf athletic fields be tested for lead.

The CDC recommended testing of any field containing worn or faded turf blades that are made of nylon or nylon-blend fibers. Nylon fields with visible dust should also be tested, the agency said in a health advisory posted online late Wednesday.

The guidelines come two months after New Jersey health officials found unexpectedly high lead levels in turf fibers of three athletic fields. Subsequent tests showed the lead found in the turf can be absorbed by humans.

New Jersey epidemiologist Dr. Eddy Bresnitz said the lead levels were not high enough to cause poisoning in people who play on the fields. However, he said the levels could cause more damage in children already exposed to lead.

Additional tests are being done to better understand the absorption of lead from turf products.

The tests done by New Jersey health officials found potentially hazardous lead levels only on worn nylon and nylon-blend athletic fields. The CDC did not recommend testing artificial turf fields made from polyethylene or nylon fields that are not visibly worn.

"As determined by New Jersey Department of Health and Senior Services, limited sampling of additional athletic fields in New Jersey and commercial products indicates that artificial turf made of nylon or nylon/polyethylene blend fibers contains levels of lead that pose a potential public health concern," the CDC advisory states. "Tests of artificial turf fields made with only polyethylene fibers showed that these fields contained very low levels of lead."

New Jersey found itself at the forefront of the issue after state health authorities stumbled onto the lead while investigating whether runoff from a scrap-metal operation in Newark had contaminated an adjacent playing field.

Pigment containing lead chromate is used in some surfaces to make the grass green and hold its color in sunlight. But it is not clear how widely the compound is used. The New Jersey Health Department found lead in three nylon fields it tested, but in none of the 10 polyethylene surfaces it examined.

The three fields in New Jersey were voluntarily ripped up and replaced.

The CDC said no cases of elevated blood lead levels in children have been linked to artificial turf.

The artificial turf industry has said its products are safe because the lead used to color the turf is encapsulated within the blades.

State authorities requested more comprehensive testing on a federal level, and the U.S. Consumer Product Safety Commission agreed. The agency is looking into the possible health hazards of lead in artificial turf installed at schools, parks and stadiums across the country.

Those results are pending.

The CDC acknowledges that it does not fully understand the potential risks associated with exposure to dust from worn artificial turf. To minimize the risk of exposure, it suggests that field managers water down fields and use other dust-suppression measures.

For people who play on turf fields, the CDC recommends thoroughly washing hands and showering immediately afterward, turning clothes inside out and washing them separately from other laundry, that athletic shoes be left outside, and that drinking containers be covered and kept in a bag or cooler when not being used.