To evaluate the type(s) of synthetic turf that are most likely to contain elevated concentrations of lead, we conducted or reviewed several investigations. These studies include data collected from the following investigations and from data provided by the CPSC investigation.
shows results of testing of synthetic turf fibers in four areas, including limited dust sampling results: a
) Data from NJDHSS include 13 recreational fields and 4 new products (residential/landscaping application) [ATSDR 2008
; Hudson Regional Health Commission (HRHC) 2008
; NJDHSS 2008
) data from New York State are from a high school—one recreational field (Life Science Laboratories 2008
) data from New York City, New York are from four recreational fields [New York City Department of Health and Mental Hygiene (NYC DHMH), unpublished data]; and d
) data from a U.S. Army Base, South Korea are from one recreational field (U.S. Army, unpublished data).
Total lead concentrations in turf fibers and in surface dust from tested synthetic surfaces: sampling period August 2007 through September 2008.
Bioaccessibility testing performed by NJDHSS in 2008
confirmed that lead in evaluated synthetic turf products became soluble under simulated digestive conditions (NJDHSS 2008
). Gastric bioaccessibility from turf fibers ranged from 14.5% to 50.9% (, surfaces 1 through 3). Gastric bioaccessibility was highest in the synthetic-based dust sample at 92.2% (, surface 3) (NJDHSS 2008
and show results of synthetic turf fiber and dust-wipe sampling at the University of Nevada, Las Vegas (UNLV), on 10 surfaces in children’s play areas in child care settings or on athletic fields (UNLV, unpublished data). UNLV also performed soil analysis in areas adjacent to the fields to identify possible non-turf sources of lead. UNLV used U.S. Environmental Protection Agency (EPA) risk assessment protocols to conduct soil and dust-wipe testing. To provide a realistic approximation of lead concentrations in the dust, we assigned a value of limit of detection (LOD)/2 to all samples below the LOD. We also present data with samples below the LOD removed (). Assigning all samples below the LOD a value equal to the LOD would likely overestimate potential exposures.
Descriptive data for soil, turf, and dust collected at child care and recreational surfaces in Clark County, Nevada, 2008.
Compiled data () show the testing results for synthetic surfaces and new products. Twelve of 29 actively used synthetic surfaces and two of four new turf products tested exceeded the statutory lead limit of 300 mg/kg for consumer products intended for use by children [Consumer Product Safety Improvement Act (CPSIA 2008
)] and the U.S. EPA lead hazard standard of 400 mg/kg for residential soil (U.S. EPA 2001
). Turf fibers exceeding the statutory limit included polyethylene, nylon, and polyethylene/nylon blends. Results indicate elevated lead concentrations predominantly in green nylon-based turf fibers and polyethylene-based turf fibers of various colors.
UNLV wipe-sampling results ranged from below the LOD to 81 μg/ft2
, which exceeded U.S. EPA’s hazard standard for floors, 40 μg/ft2
(U.S. EPA 2001
) [ and ; also see Supplemental Material, Figure 2 (doi:10.1289/ehp.1002239)]. Wipe sampling results were available for six surfaces (surfaces 22–26, and 28; ) which exceeded the CPSIA lead limit of 300 mg/kg (CPSIA 2008
), with one surface exceeding the U.S. EPA lead dust hazard standard for floors, 40 μg/ft2
. Background testing indicated soil-lead concentrations that were all < 20 mg/kg. Additionally, three New Jersey fields showed lead loading greater than the U.S. EPA lead-dust hazard standard (U.S. EPA 2001
The CPSC tested lead in turf fibers from four manufacturers/vendors (CPSC 2008
). Concentrations ranged from nondetectable to 9,600 mg/kg. Using a wipe-sampling method developed for testing pressure-treated wood, CPSC sampled eight fields (five identified as “in use”) from the four manufacturers. The reported years of installation of the fields ranged from 1999 (one field) to 2008 (two fields).
The CPSC’s guidance policy advises that exposures of > 15 μg lead/day may result in blood-lead levels of 10 μg/dL in children (CPSC 1998
); the CPSC used this guidance policy for sample comparison. The average of three dust-wipe samples from the oldest field, containing an average of 5,500 mg/kg lead in turf fibers, was 68 μg/400 cm2
wipe area (i.e., 158 μg/ft2
). The CPSC divided the wipe-sample results by five to approximate the amount of wiped material that may transfer to children’s hands. The CPSC also assumed that children transfer 50% of the lead on their hands into their mouths. All the lead intake estimates were < 15 μg/day, and CPSC concluded that young children are not at risk from lead exposure at synthetic fields (CPSC 2008
). However, for the oldest field tested, CPSC estimated an average lead intake of 6.8 μg/day. This estimation supports our supposition that as turf fields age, they can deteriorate and increase the risk of cumulative lead exposures to children.