In April of this year, two playing fields in New Jersey that use synthetic turf were closed after state health officials detected what they said were unexpectedly high levels of lead within the synthetic turf, which raised fears that children could inhale or swallow fibers or dust from the playing surface. Pigment containing lead chromate is often used in synthetic turf to make it green and retain its color.
Health officials finalized their study of the materials and have found that unless under extraordinary circumstances, children are under no risk.
MLB currently uses synthetic turf in only two facilities (Metrodome and Tropicana Field), while there are many more at the minor league level.
There are approx. 3,500 synthetic playing surfaces across the U.S.
Synthetic turf test results released by the New Jersey Department of Health and Senior Services (NJDHSS) on June 3rd confirmed lead chromate levels are well below that necessary to cause harm to children and athletes using the popular playing field surfaces.
Lead chromate has been used in a number of synthetic turf fields to extend the life of its colorfastness. Testing three fields in New Jersey with elevated lead levels, the NJDHSS focused on the bioaccessibility of synthetic turf, which it defines as "the fraction of a substance in a material that is soluble and made available for absorption" by the body.
From its tests, the NJDHSS reported that the amount of lead chromate contained in fibers from the three fields available for absorption in the intestine, which is where food altered by stomach acid is absorbed by the blood and lymphatic systems, ranged from 2.5% to 11%.
A couple of interesting findings:
- According to calculations made by forensic toxicologist Dr. David Black, a 50 lb. child would have to ingest over 100 lbs. of synthetic turf to be at risk of absorbing enough lead to equal the minimum threshold of elevated blood lead. That level is even more unreachable than Dr. Black's original worst case bioaccessibility, which was based on ingesting 23 lbs. of turf.
- The Consumer Product Safety Commission's guidance states that young children "should not chronically ingest more than 15 micrograms of lead per day from consumer products." Putting these test results in perspective, polymer and fiber engineering specialist Dr. Davis Lee calculated that a child playing on the three New Jersey fields would have to wipe his fingers on the turf and put them in his mouth 750 times in a day to receive enough lead to equal the CPSC threshold level.
One would expect and hope that children are not conducting these types of activities.
Source: Synthetic Turf Council