Human Health Risk Assessment of Synthetic Turf Fields Based Upon

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Journal of Toxicology and Environmental Health, Part A: Current Issues Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/uteh20 Human Health Risk Assessment of Synthetic Turf Fields Based Upon Investigation of Five Fields in Connecticut Gary Ginsberg a , Brian Toal a , Nancy Simcox b , Anne Bracker c , Brian Golembiewski d , Tara Kurland e & Curtis Hedman f a Connecticut Dept of Public Health, Hartford, Connecticut, USA b University of Connecticut Health Center, Farmington, Connecticut, USA c Connecticut OSHA, Hartford, Connecticut, USA d Connecticut Department of Environmental Protection, Hartford, Connecticut, USA e Clark University, Worcester, Massaschusetts, USA f Wisconsin State Laboratory of Hygiene, Madison, Wisconsin, USA Published online: 28 Jul 2011.

To cite this article: Gary Ginsberg , Brian Toal , Nancy Simcox , Anne Bracker , Brian Golembiewski , Tara Kurland & Curtis Hedman (2011) Human Health Risk Assessment of Synthetic Turf Fields Based Upon Investigation of Five Fields in Connecticut, Journal of Toxicology and Environmental Health, Part A: Current Issues, 74:17, 1150-1174, DOI: 10.1080/15287394.2011.586942 To link to this article: http://dx.doi.org/10.1080/15287394.2011.586942

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HUMAN HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS BASED UPON INVESTIGATION OF FIVE FIELDS IN CONNECTICUT

Gary Ginsberg1, Brian Toal1, Nancy Simcox2, Anne Bracker3, Brian Golembiewski4, Tara Kurland5, Curtis Hedman6 1Connecticut Dept of Public Health, Hartford, Connecticut 2University of Connecticut Health Center, Farmington, Connecticut 3Connecticut OSHA, Hartford, Connecticut 4Connecticut Department of Environmental Protection, Hartford, Connecticut 5Clark University, Worcester, Massaschusetts 6Wisconsin State Laboratory of Hygiene, Madison, Wisconsin, USA

Questions have been raised regarding possible exposures when playing sports on synthetic turf fields cushioned with crumb rubber. Rubber is a complex mixture with some components possessing toxic and carcinogenic properties. Exposure is possible via inhalation, given that chemicals emitted from rubber might end up in the breathing zone of players and these players have high ventilation rates. Previous studies provide useful data but are limited with respect to the variety of fields and scenarios evaluated. The State of Connecticut investigated emissions associated with four outdoor and one indoor synthetic turf field under summer conditions. On-field and background locations were sampled using a variety of stationary and personal samplers. More than 20 chemicals of potential concern (COPC) were found to be above background and possibly field-related on both indoor and outdoor fields. These COPC were entered into separate risk assessments (1) for outdoor and indoor fields and (2) for children and adults. Exposure concentrations were prorated for time spent away from the fields and inhalation rates were adjusted for play activity and for children’s greater ventilation than adults. Cancer and noncancer risk levels were at or below de minimis levels of concern. The scenario with the highest exposure was children playing on the indoor field. The acute hazard index (HI) for this scenario approached unity, suggesting a potential concern, although there was great uncertainty with this estimate. The main contributor was benzothiazole, a rubber-related semivolatile organic chemical (SVOC) that was 14-fold higher indoors than outdoors. Based upon these findings, outdoor and indoor synthetic turf fields are not associated with elevated adverse health risks. However, it would be prudent for building operators to provide adequate ventilation to prevent a buildup of rubber-related volatile organic chem- Downloaded by [University of Connecticut] at 07:51 29 August 2013 icals (VOC) and SVOC at indoor fields. The current results are generally consistent with the findings from studies conducted by New York City, New York State, the U.S. Environmental Protection Agency (EPA), and Norway, which tested different kinds of fields and under a variety of weather conditions.

Received 20 January 2011; accepted 7 April 2011. This article and underlying reports were reviewed by staff from the Connecticut Department of Public Health, the Connecticut Department of Environmental Protection, the University of Connecticut Health Center, Section of Environmental and Occupational Medicine, and the Connecticut Agricultural Experiment Station. The Connecticut Academy of Science and Engineering reviewed the underlying reports and made formal recommendations (CASE, June 15, 2010 report), which were incorporated into the final reports and are reflected in this article. The field, laboratory work and CASE review were funded by the Connecticut Department of Environmental Protection. Address correspondence to Gary Ginsberg, Connecticut Dept. of Public Health, 410 Capitol Ave., Hartford, CT 06106, USA. E-mail: [email protected]

1150 HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1151

Questions have been raised regarding This project is a follow-up of an earlier pilot potential exposures and health risks associated study by CAES (2007). A separate analysis with playing on artificial turf fields cushioned of ecological risks associated with rainwater with crumb rubber (Brown 2007). This is a form runoff from these fields was performed by the of recycling, as the crumb rubber is produced Connecticut Department of Environmental from the shredding of discarded tires. Tires Protection (CTDEP 2010). can be made from natural or synthetic rubber, The overall objective was to develop a both of which are complex mixtures of chemi- screening level risk assessment in which high- cals that include polycyclic aromatic hydrocar- end assumptions for exposure were used for bons (PAH), volatile organic chemicals (VOC), uncertain parameters and surrogate data were nitrosamines, benzothiazoles, latex, and heavy employed for chemicals with inadequate toxic- metals. Therefore, there is a potential for expo- ity information so that chemicals did not fall out sure and health risk from playing on these of the assessment on the basis of missing data. fields. Exposure is expected to be greatest via If the risks projected with this approach are not the inhalation route under warm summertime elevated into a range of concern, then there is conditions, as some components vaporize into little need to refine exposure assumptions or the breathing zone of athletes. Further, running perform a more detailed analysis. may break down the crumb rubber and emit particles into the air just above the field. The higher ventilation rate during active play further METHODS enhances the potential for inhalation exposure. Therefore, this risk assessment focused upon Field Investigations the inhalation route of exposure. The current project involved investigation The current investigation adds to a growing at five polyethylene grass fields cushioned with body of data describing crumb rubber-based crumb rubber infill located in Connecticut. athletic fields (U.S. Environmental Protection Four are outdoor fields (designated as A, B, Agency [EPA] 2009a; NYSDEC 2009a; TRC C, D) and one indoors (designated as K). 2009; NILU 2006; Norwegian Institute of Sampling occurred during July 2009 (Figure 1). Public Health 2006; California Office of Field selection was based upon the ability to Environmental Health Hazard Assessment gain access, the availability of electrical out- [OEHHA] 2007; KEMI 2006; LeDoux 2007; lets to run the stationary sampling equipment, Bristol and McDermott 2008), and it is unique and obtaining a variety of field ages (range in providing personal monitoring results for 2 to 5 yr old). The outdoor fields were all users of the field during active play. Further high school football or soccer fields, while the

Downloaded by [University of Connecticut] at 07:51 29 August 2013 it is the only apparent study in the United indoor field was a collegiate facility. Three to States that assessed an indoor soccer field. 4 volunteers played soccer for a 2-h sampling Each field was investigated on its own day event at each field. The activity consisted of of fieldwork during July 2009, under sunny, drills and scrimmages with brief breaks taken warm, and low wind weather conditions to for water and equipment checks on an as- maximize the potential of detecting off-gassed needed basis. Each player was equipped with rubber components. Details of the sampling a variety of personal sampling devices as listed plan, methodology and results of field testing, in Table 1 and as described in more detail else- analytical chemistry, and off-gas headspace where (Simcox et al. 2011). Volunteers were experiments are found in companion papers instructed to avoid personal care products on (Li et al. 2010; Simcox et al. 2011). An the day of testing. Soccer was played on a small independent review of the underlying reports portion of the field to maximize the local par- was conducted by the Connecticut Academy ticulate emission and stationary samplers were of Science and Engineering (CASE 2010). located in the immediate vicinity of the play. 1152 G. GINSBERG ET AL.

July 2009 Summa cans, Personal Monitors, Stationary Monitors, Meterology, Soccer balls

4 Outdoor Fields 1 Indoor Field

VOCs, SVOCs, VOCs, SVOCs, Rubber SVOCs, Rubber SVOCs, Nitrosamines, Nitrosamines, PM10, Lead PM10, Lead

Air Concs, Lead in Infill/Grass Air Concs, Lead in Infill/Grass

HHRA Child & Adult HHRA Child & Adult

FIGURE 1. Outline of Connecticut synthetic turf air study.

TABLE 1. Numbers of Samples Taken at Each Field

Sample type VOC SVOC Rubber SVOC Nitrosamines PM10

Personal monitor 2 0 2 2 0 Stationary on-ﬁeld 6 inch 1 0 2 1 0 Stationary on ﬁeld 3 feet 1 1 2 1 1 Stationary upwind 1 1 2 2 1 Community —a —a —a —a —a

aThe community field was tested in similar fashion as the synthetic turf fields—three personal monitors plus stationary upwind and on field monitors.

Sampling and analysis were conducted for the target analytes (community location, des- a wide range of VOC, semivolatile organic ignated field L). Soccer was also played at the compounds (SVOC), rubber-related SVOC, community grass field to serve as a background lead (Pb), and particulate matter in the less than data source for the personal monitors; this was 10 µmrange(PM10). This included sampling needed to evaluate the possibility that some for a suite of 60 VOC, 120 SVOC divided into VOC detected in the personal monitors may 22 polycyclic aromatic hydrocarbons (PAH), have originated from the sampling equipment 5 targeted (potentially rubber-related) SVOC, or exhaled breath of the soccer player rather and 93 miscellaneous SVOC, 7 nitrosamines, than the field. and PM10 (Simcox et al. 2011). As shown in Volatile organic chemicals, targeted SVOC,

Downloaded by [University of Connecticut] at 07:51 29 August 2013 Table 1, different samplers were employed in and nitrosamines were sampled in both sta- the hopes of identifying analytes originating tionary and personal samplers, while the other from the field as opposed to general air pol- analytes were collected in stationary samplers lutants. Personal monitors were attached to the only. All analytes were assessed in the upwind, belt of each player to determine what may be off-field location and in the community back- in the breathing zone of a young child playing ground sample using stationary samplers. This on the field. Stationary monitors located away led to 5 types of samples for VOC and tar- from the play at 6 inches or 3 ft above the field geted SVOC: stationary, field height (6 inches); were intended to study the vertical gradient of stationary, 3 ft; personal monitor; off-field contaminants emitted from the field. Upwind upwind; and off-field community. For PAH and samples were taken off the synthetic turf sur- miscellaneous SVOC there were three types face (usually on grass) at each field. A separate of samples: on turf, upwind, and community round of sampling was conducted at a subur- background. Data from the community back- ban location at a grass field near a busy road ground sample were combined with the other to assess general ambient background levels of background samples taken at each field to yield HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1153

a range of background results for comparison to generally only use the ventilation system to on-ﬁeld results. regulate temperature on hot days.

Exposure Assessment Selection of Contaminants of Potential The primary objective of this field inves- Concern tigation and risk assessment was to estimate exposures and risks for children playing on An analyte became a contaminant of the fields. Due to the possibility that adults potential concern (COPC) if it was detected using these fields might encounter higher expo- on the field at higher concentration than in sures due to a longer period of usage, they background samples. Due to the small num- were also considered as a separate element. ber of samples and background taken at any Separate analyses were conducted for data one field, there would be low confidence in pooled from the outdoor fields vs. the one making decisions about contaminant emissions indoor field yielding four sets of exposure and at a particular field. Therefore, for the four risk estimates: child-indoors, child-outdoors, outdoor fields, the results were pooled and adult-indoors, adult-outdoors. Given that field the highest on-field result (regardless of sam- sampling occurred in July under sunny, low ple type) was taken to represent what might wind conditions, off-gassing from the outdoor be coming off the fields. This was then com- fields would be overestimated if the entire 8 pared to the range of background results. If the mo/yr exposure period were simulated based highest field result was 25% above the highest upon these results. Instead, it was assumed that background result, the analyte was considered estimates of inhaled VOC apply to the four a COPC. This ensured that for an analyte to warmest months with no allowance for days become a COPC its on-field and background with clouds or high wind which would mitigate detects did not overlap. The range of back- exposure. No such adjustment was made for ground results was inspected to ensure that the indoor field, as the results from our 1-day the highest background was not an outlier, investigation may be representative of each day in which case the next highest result would the facility is operational. Another conservative be used. If a contaminant was judged to be assumption was that the highest concentration a COPC on this basis, its entire concentra- for each analyte found at any of the outdoor tion was considered to be field-related—there fields was combined across fields to represent was no background correction, even though in a worst case composite. This approach obviates some cases the on-field result was only slightly > the need for five separate risk assessments. (albeit 25%) above the background result. All Various exposure routes are possible for Downloaded by [University of Connecticut] at 07:51 29 August 2013 COPC were carried through the risk assessment crumb rubber-related chemicals as follows: process. The indoor field (field K) is treated as • a separate case because the conditions and Inhalation of volatile or semivolatile chemi- results are substantially different than outdoors. cals that off-gassed from the rubber. • A quick scan of the data indicated that if the Inhalation of particles and particle-borne indoor field were lumped in with the other chemicals. • fields, that it would often be the highest detect Ingestion of crumb rubber or the dust created and the assessment would be driven by results from the breakdown of crumb rubber. • from the indoor field. The greater concentra- Dermal uptake of chemicals contained in tions indoors provide confidence that measure- crumb rubber that contact the skin. ments from the field were above background in spite of the small sample size. Field K did not The current risk assessment focused upon display active ventilation at the time of sam- the first two pathways, inhalation of off-gassed pling; this is typical for indoor fields as they and particle-bound chemicals. Ingestion of 1154 G. GINSBERG ET AL.

crumb rubber or dust derived from crumb ventilation adjustment is needed because rubber was not a focus, as this pathway was toxicity values are based upon studies in ani- evaluated elsewhere without being identified mals or humans in which the subjects were at as a public health risk (Norwegian Institute rest or undergoing light exercise (e.g., workers). of Public Health and Radium Hospital 2006; Further, these data come from adult animals or California EPA 2007) and field methods were humans and thus do not necessarily capture not designed to measure the amount of dis- the increased exposure possible for younger lodgeable dust that might occur on the surface children (Ginsberg et al. 2010). The follow- of these fields and end up becoming ingested. ing equation shows the ventilation adjustment The fields did not appear to be especially dusty (adj) along with the time-weighted averaging and the crumb rubber that clings to clothing used to calculate inhaled doses that relate and body parts is of relatively large size, making to chronic exposure and risk. For short-term its ingestion more of an intentional event char- (acute) exposures, the ventilation-adjusted air acteristic of younger age groups and covered concentration (conc) was used directly without by the prior oral crumb rubber risk assess- time averaging. ment conducted in California (California EPA 2007). Dermal exposure was also not a focus Inhaled conc (µg/m3) as most chemicals in rubber are not a reliable ∗ ∗ candidate for dermal absorption: The volatile Measured conc (µg/m3) hours per day ∗ ∗ fraction tends to revolatilize off skin and thus = days per year years ventilation adj not remain long enough for substantial dermal Averaging time penetration; the particle-bound fraction tends to remain bound to the rubber, rather than par- The ventilation adjustment for adults is tition into and penetrate through the skin. No based upon exertion-induced increases in the apparent data were found describing the trans- amount of air inhaled going from the typical fer of SVOC from a rubber matrix to skin, but assumption of light exercise (0.0148 m3/min this would not appear to be a large uncertainty. or 21.4 m3/d) to the higher ventilation rate Further support for this is that the fields are associated with sports play as described in not highly dusty and players do not become the U.S. EPA Exposure Factors Handbook (U.S. coated with dust particles, although larger rub- EPA 2009b). For this one assumes a moder- ber particles do cling to clothing and penetrate ate (0.039 m3/min) level of exercise for the inside shoes. The Norwegian study evaluated 3 h of play, which accounts for the fact that dermal exposure to crumb rubber particles and periods of time are spent resting or listening did not find this to be a significant risk path- to instructions while other periods would elicit 3 Downloaded by [University of Connecticut] at 07:51 29 August 2013 way (Norwegian Institute of Public Health and an intense level of exercise (0.073 m /min). Radium Hospital 2006). This creates an adult ventilation adjustment of 2.64 (0.039/0.0148 m3/min). A further adjustment is made for the ventilation rate in children Exposure Scenarios based upon their greater rate per body weight Table 2 presents key assumptions for the and respiratory surface area. A recent review child and adult scenarios used to develop and analysis (Ginsberg et al. 2010) indicated exposure estimates. Exposure was adjusted to that a threefold factor is appropriate for the account for differences in ventilation rates dur- first 3 yr of life, with this decreasing to a ing active play and in children. This adjusts the 1.5-fold adjustment for ages 4–10 yr. Given exposure concentration rather than the dose that this adjustment applies to a portion of the received because the toxicity values (refer- childhood exposure period simulated in this ence concentration—RfC; cancer unit risk fac- assessment, the 1.5-fold factor is conservatively tor) are in terms of air concentration (µg/m3) applied to the child scenario overall rather than rather than intake dose (e.g., mg/kg/d). The dividing it into two assessments (young vs. older HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1155

TABLE 2. Exposure Parameters

Parameter Child Adult Basis

Age (yr) 12 30 Child—midpoint of 6–18 yr range Years exposed 12 30 Child—youth to high school soccer; Adult—90th% residence at one location Exposure time per event 3 h 3 h Time for soccer match or practice Days exposed per year 138 138 4 d/wk for 8 months (spring, fall soccer + 2 mo in summer) Days exposed per year VOC 69 69 VOC offgas only in the four warm months for outdoor ﬁelds; no adjustment for indoor ﬁelds Ventilation adjustment 3.96 2.64 Child—Adult factora child factor Adult—moderate exercise Averaging time (cancer) 25,550 d 25,550 d Entire lifespan—70 yr Averaging time (noncancer) 4380 d 10,950 d Entire exposure period

child). This factor is applied on top of the for the underreporting of risk. When data were adult ventilation adjustment to yield a 3.96-fold not available for a particular analyte, a related adjustment for children (Table 2). surrogate that has toxicity data was used that reflects a high end of the likely potency. For example, all noncarcinogenic PAH and other Toxicity Assessment miscellanous SVOC that lack RfC were assigned COPC over a broad array were identified, the RfC for pyrene, which is the lowest RfC some of which have an extensive toxicology available for the general series of PAH. database and others that do not. This toxicity Table 3 summarizes the toxicology values assessment relies upon national databases of used for COPC in this assessment. Chemical- toxicity potency values as available from the specific toxicology monographs are generally U.S. EPA Integrated Risk Information System available from the cited sources (e.g., IRIS, (IRIS) (http://www.epa.gov/iris), California’s California OEHHA, ATSDR). However, this is Office of Environmental Health Hazard not the case for benzothiazole, which is of Assessment (OEHHA) (http://www.oehha. particular interest because it is a known rub- ca.gov/risk/chemicalDB/index.asp), and the ber constituent that consistently is found in

Downloaded by [University of Connecticut] at 07:51 29 August 2013 Agency for Toxic Substances and Disease the air above the outdoor and indoor fields. Registry (ATSDR) (http://www.atsdr.cdc.gov/ Benzothiazole received relatively little toxic- mrls) as the primary sources of toxicity infor- ity assessment in the past; Ginsberg et al. mation. By convention, IRIS is typically the first (2011) provide a toxicity assessment for this choice. However, when values are available compound in a companion paper. from multiple sources are compared and in In addition to chronic cancer and non- cases where there is considerable disagree- cancer toxicity values (unit risks and RfC ment (threefold or greater), the Connecticut respectively), this assessment utilizes acute risk Department of Public Health (CT DPH) eval- air targets as well. Short-term exposure to uated the underlying difference and selected COPC might trigger an irritant or neurologi- values that best reflect the most recent and cal response, or some other acute effect. To robust treatment of the available science. evaluate this potential requires acute exposure Given the screening nature of this risk toxicity values that would be the equivalent assessment, toxicity values were assigned in a of a 3-h RfC, since our exposure assessment conservative manner to decrease the potential was for 3 h of play per event. These values 1156 G. GINSBERG ET AL.

TABLE 3. Toxicity Values for COPC

Cancer Acute unit risk RfC target Analyte (µg/m3)Source (µg/m3)Source (µg/m3)Source

VOC Acetone NA — 1050 IRIS RfD for renal 8000 CTAEC for irritation effect converted to based upon RfC; 3× uncertainty human irritation factor (UF) added threshold divided for lower dose by 3 to convert 1 h effects in a gavage AECto3htime study not used by frame IRIS and lack of RfC. Carbon disulﬁde NA — 700 IRIS for peripheral 1000 CTAEC for neurotoxicity neurotoxicity and odor threshold Chloromethane 1.7E-06 California Prop 65 90 IRIS for CNS toxicity 1000 ATSDR acute MRL for neurotoxicity Cyclohexane NA — 6000 IRIS for reproductive 6000 No acute guideline effects available so RfC used Heptane NA — 700 No tox values 700 No acute guideline available; hexane as available so RfC conservative used surrogate Hexane NA — 700 IRIS for neurotoxicity 700 No acute guideline available so RfC used Methylene chloride 4.7E-07 IRIS 400 California OEHHA for 4700 California acute REL cardiovascular and for neurotox nervous system divided by 3 for toxicity 1hto3h conversion Methyl ethyl ketone NA — 1000 California OEHHA for 3233 CTAEC for irritation reproductive effects; in humans divided value is 5× < IRIS by 3 for time conversion Methyl isobutyl NA — 80 U.S. EPA HEAST, 1997, 4550 CTAEC for irritation, ketone for liver/kidney headache divided toxicity by 3 for time conversion Styrene NA — 100 IRIS RfC for neurotox 4133 CTAEC for neurotox divided by 10 for divided by 3 for

Downloaded by [University of Connecticut] at 07:51 29 August 2013 possible time conversion carcinogenicity Toluene NA — 300 ATSDR MRL for 3800 ATSDR acute MRL neurotox—a value for neurotoxicity lower than California or IRIS Xylene NA — 100 IRIS for neurotoxicity 7333 California acute REL for neurotox divided by 3 for time conversion Targeted SVOC Benzothiazole 1.8E-07 Whittaker et al., 18 NYS DEC (2009) value 110 CTDPH value based 2004 cancer slope based on subchronic on 18× higher for 2-MBZT and oral NOAEL and RD50 than route extrapolation route extrapolation formaldehyde and 10× UF for data gaps

(Continued) HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1157

TABLE 3. (Continued)

Cancer Acute unit risk RfC target Analyte (µg/m3)Source (µg/m3)Source (µg/m3)Source

Butylated hydroxytoluene NA — 175 European ADI of NA — 0.05 mg/kg/dand route extrapolation PAH Acenaphthene NA — 210 IRIS RfD for NA — hepatotoxicity with route extrapolation Acenaphthylene NA — 210 No data; NA — acenaphthene as surrogate Benz[a]anthracene 1.1E-04 Unit risk for BaP 110 Pyrene IRIS RfD NA — with relative converted to RfC as potency of 0.1 surrogate—lowest from U.S. EPA, RfC available 1993 Benzo[a]pyrene (BaP) 1.1E-03 California EPA 110 Pyrene IRIS RfD NA — (1999) unit risk converted to RfC as from hamster surrogate inhalation bioassay Benzo[e]pyrene NA — 110 Pyrene IRIS RfD NA — converted to RfC Benzo[b]ﬂuoranthene 1.1E-04 Unit risk for BaP 110 Pyrene IRIS RfD NA — with relative converted to RfC as potency of 0.1 surrogate as lowest from U.S. EPA, RfC available 1993 Benzo[k]ﬂuoranthene 1.1E-05 Unit risk for BaP 110 Pyrene IRIS RfD NA — with relative converted to RfC as potency of 0.01 surrogate as lowest from U.S. EPA, RfC available 1993 Benzo[ghi]perylene NA — 110 Pyrene IRIS RfD NA — converted to RfC Chrysene 1.1E-05 Unit risk for BaP 110 Pyrene IRIS RfD NA — with relative converted to RfC as potency of 0.001 surrogate as lowest from U.S. EPA, RfC available 1993

Downloaded by [University of Connecticut] at 07:51 29 August 2013 Fluoranthene NA — 140 IRIS RfD and route NA — extrapolation Fluorene NA — 140 IRIS RfD and route NA — extrapolation Naphthalene 3.4E-05 Unit risk from 3 IRIS RfC for 117 CTAEC for acute tox California respiratory to Clara cells in OEHHA hyperplasia mice divided by 3 for time conversion 1-Methylnaphthalene 3.4E-05 Naphthalene as 3 Naphthalene as 117 Naphthalene as surrogate surrogate surrogate 2-Methylnaphthalene 3.4E-05 Naphthalene as 3 Naphthalene as 117 Naphthalene as surrogate surrogate surrogate 2,6-Dimethylnaphthalene 3.4E-05 Naphthalene as 3 Naphthalene as 117 Naphthalene as surrogate surrogate surrogate Phenanthrene NA — 110 IRIS RfD and route NA — extrapolation

(Continued) 1158 G. GINSBERG ET AL.

TABLE 3. (Continued)

Cancer Acute unit risk RfC target Analyte (µg/m3)Source (µg/m3)Source (µg/m3)Source

Pyrene NA — 110 IRIS RfD for renal NA — pathology and route extrapolation Miscellaneous SVOC NA — 110 No values available, NA — (aliphatics, used pyrene as hopanes, terpenes, conservative pristanes) surrogate

Note. Abbreviations: NA, not applicable; IRIS, U.S. EPA Integrated Risk Information System online database of toxicity values; California OEHHA, California Ofﬁce of Environmental Health Hazard Assessment; ATSDR MRL, Agency for Toxic Substances and Disease Registry minimum risk level as provided in the toxicological proﬁle; CTAEC, CT DPH acute exposure concentrations for 1-h exposure developed in 2000 and updated in 2010 for targeted analytes.

typically do not exist. However, for a limited set given that they are not highly reactive and tend of chemicals, 1-h acute targets were derived by to produce chronic effects instead. California OEHHA (acute Reference Exposure The following highlight some of the toxicol- Level [REL]) and by Connecticut DPH (CT acute ogy assessment decisions made in the face of exposure concentrations, AEC). These values limited or conﬂicting information: were used along with ATSDR acute minimum risk level (MRL) (typically on a basis of 24 h of Chloromethane—This chemical is generally continuous exposure) to develop 3-h acute air regarded as a mutagen with limited can- targets in this assessment. These acute targets cer bioassay data suggesting some activ- were set based upon evidence of a threshold in ity. However, the U.S. EPA and California short-term studies (often in humans) with the OEHHA did not derive unit risks. Rather use of variability and uncertainty factors on a than count chloromethane as having no can- case-by-case basis. In consideration of Haber’s cer risk, this assessment uses a unit risk law, a 1-h target developed for other purposes developed by the California Proposition 65 was converted to a 3-h target by dividing by 3. committee for the purposes of assessing The 1-h levels were prioritized over the ATSDR potential health risks from its presence in acute MRL because the MRL relate to a longer consumer products. time frame, 24 h continuous exposure basis. Heptane—This solvent lacks an RfC in the Further, the level of conservatism and time- standard sources and was not extensively

Downloaded by [University of Connecticut] at 07:51 29 August 2013 factor adjustment in the ATSDR values are not studied. However, it is known to be less necessarily consistent or always transparent. neurotoxic than its congener hexane. As a Another conservative screening level approach conservative screening approach, the RfC for was to use the chronic RfC in several cases hexane was used. where an acute value was not available. Styrene—Its cancer database is limited and As seen in Table 3, all COPC were assigned conﬂicting; it has positive mutagenicity data RfC, 12 have cancer unit risk values and 17 and the main metabolite, styrene oxide is have acute targets. Only those analytes hav- mutagenic. Therefore, an additional uncer- ing direct or indirect (e.g., structurally related tainty factor was added to the IRIS RfC to to carcinogen or clearly mutagenic) evidence account for the possibility that it exerts car- of carcinogenicity were assigned unit risk val- cinogenic action. Carcinogens typically have ues. Acute targets were assigned only for the much lower de minimis targets than nonper- volatile analytes, as the acute effects of particle sistent noncarcinogens that bear an RfC. bound chemicals such as PAH have not been Benzothiazole—This agent has little toxicology well explored but are expected to be minor, data but was positive in one mutagenicity HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1159

test and has a structural analogue that is was not available and the target site is carcinogenic (2-mercaptobenzothiazole or systemic rather than at the point of contact. 2-MBZT). The acute toxicity value was Assumptions for dose route conversion are derived based upon analogy with formalde- inhalation of 20 m3 per day for a 70-kg adult. hyde. Both compounds were tested in Children’s Cancer Potency—According to mouse respiratory depression (RD50) stud- the U.S. EPA Carcinogen Risk Assessment, ies by the same laboratory and found to Supplemental Guidance for Early Life Stages be irritating. Benzothiazole potency was (U.S. EPA 2005), children have greater 18-fold below formaldehyde. Given the vulnerability to a variety of carcinogens, uncertainties in extrapolating from an ani- with the evidence particularly strong for mal screening test to humans and the fact those with a mutagenic mode of action. that benzothiazole can produce sensitiza- For these carcinogens, the Supplemental tion (at least on the skin), an additional Guidance recommends the following 10-fold uncertainty factor was applied to enhanced potency factors above adult derive the acute target. The derivation of potency: 10-fold for 0–2 yr of age and cancer, noncancer, and acute toxicity values 3-fold for 3–15 yr of age. For the purposes for benzothiazole is further described in a of this assessment, the child exposure companion paper (Ginsberg et al. 2011). scenario (age 12 yr average; range 6–18) is Butylated hydroxytoluene (BHT)—There are considered to be at heightened vulnerability no toxicity values but BHT is a common food and receives the enhanced threefold factor. preservative. The European Union (EU) has This applies to all carcinogens that have an acceptable daily intake based upon tox- documented mutagenic or clastogenic activ- icology concerns of 0.05 mg/kg/d, which is ity and included as COPC: cloromethane; threefold lower than the U.S. Food and Drug methylene chloride; benzo[a]pyrene and Administration (FDA) intake limit. The EU related carcinogenic PAH; and benzoth- value was converted to inhalation by dose iazole. The carcinogenicity and mode of route extrapolation for the current purposes. action of benzothiazole are uncertain but Naphthalenes—Naphthalene does not have a in limited testing it was mutagenic and cancer unit risk on IRIS and is negative in thus is included in this list. Naphthalene genetic toxicity testing. However, naphtha- and its congeners have limited cancer and lene produced lung tumors in mice in a mechanistic/mutagenic data with their National Toxicology Program (NTP) (1992) cancer classiﬁcation not well established. cancer bioassay and olfactory neuroblas- Therefore, an additional children’s potency tomas in a rat bioassay (NTP 2000). This factor was not applied for naphthalene and

Downloaded by [University of Connecticut] at 07:51 29 August 2013 chemical also has an IARC category 2B its related analytes. cancer classiﬁcation and is listed by the National Toxicology Program as a carcinogen. California OEHHA derived a unit risk Risk Characterization factor based upon the NTP testing, and this This assessment used standard risk assess- is the potency value used in the current ment methods to estimate cancer and non- assessment. The U.S. EPA risk-based concen- cancer risks. Prorated time-weighted aver- tration tables also list this unit risk value. The age exposures were calculated based upon other naphthalenes considered COPC are the highest measured analyte concentration, closely related to naphthalene and lack ade- amount of time playing (3 h/d, 138 d per quate cancer bioassay data to make separate year), exercise-induced breathing rate, and determinations. years of exposure (12 or 30). For carcinogens, Dose route extrapolation—This was done in the lifetime average daily exposure, in units of selected cases where an inhalation value micrograms per cubic meter, was multiplied by 1160 G. GINSBERG ET AL.

the cancer unit risk or the adjusted unit risk for RESULTS children, to yield the lifetime cancer risk esti- Contaminants of Potential Concern mate. Risks for an individual carcinogen were added to other carcinogen risks to yield the Of the 60 VOC for which analyses were total cancer risk associated with playing on the conducted, 10 are considered COPC at the field under the current scenarios and assump- outdoor fields while 13 are COPC at the indoor tions. Risk estimates above 1E-04 are consid- field (Tables 4 and 5). Personal monitoring ered substantially elevated relative to U.S. EPA results tended to give the highest VOC detec- Superfund guidance (acceptable risk range up tions relative to stationary samplers at both to 10–4), background air toxics risk estimates indoor and outdoor fields. The VOC COPC for U.S. census tracts, which are typically esti- were above the range of background detec- mated at a cumulative cancer risk of 1E-05 to tions at only one of the outdoor fields (not the 1E-04 (U.S. EPA NATA 2005; Woodruff et al. same field in each case) except for hexane and 1998), and California regulatory air target lim- toluene, in which this was true for two fields. its (cancer risk of 1E-05). Cancer risks below In general, detections in synthetic turf personal 1E-06 are considered de minimis. Cancer risks monitoring samples were 1.5- to 3-fold greater between 1E-06 and 1E-04 are in an interme- than background samples at outdoor fields, diate zone, which may require more detailed with the one exception being methylene chlo- review of uncertainties and data sources, acqui- ride, in which there was a 12.8-fold elevation sition of additional data, and, under certain (Table 4). Indoor VOC detections tended to circumstances, some type of intervention. have greater elevations relative to background For noncarcinogens, the average daily dose (Table 5). during the exposure window (12 or 30 yr) Personal sampler results tended to be was divided by the RfC to create the haz- higher, in some cases much higher, than the ard quotient (HQ). These time frames, 12 and stationary field results. This raised the question 30 yr, are considered chronic for the pur- of whether the finding in personal monitor- poses of comparison to the RfC, which is ing samples was field related, especially in usually thought of as the lifetime exposure tar- cases where the analyte was not detected in get that is without significant risk for adverse any field-related samples (including the indoor effect. HQ values for individual analytes may field) and in which the headspace studies of or may not be additive across analytes depend- crumb rubber from these fields failed to detect ing upon whether target sites and mechanisms the analyte (Li et al. 2010; Simcox et al. of action are similar. However, to conservatively 2011). The personal monitoring at the grass screen for noncancer risk issues, this assessment field community location (site L) also served

Downloaded by [University of Connecticut] at 07:51 29 August 2013 assumes that all noncancer risks are additive as a background comparison for these data. across chemicals to yield a cumulative hazard Detections in personal monitoring samples that index (HI). were excluded from the risk assessment are For acute risk calculation, the nonprorated shown in Table 6. In most cases, not only highest field concentration was adjusted by the were the analytes absent from headspace stud- enhanced ventilation rate and then divided by ies of crumb rubber, they were also present in the acute air target to create the acute HQ. background personal monitoring samples from These acute risks may or may not be addi- play on grass fields. Acrolein and benzene are tive across chemicals, as some are based upon examples in which detections may arise spuri- irritation and others are based on neurological ously in personal monitors and thus confound effects, internal organ damage, or reproductive a risk assessment (Figures 2 and 3). The pat- effects. As a crude, conservative screen, this tern showed detections in personal monitors assessment assumed that the individual acute but generally not in other field-related samples, risks were additive across chemicals to yield a with the results for the background (grass field) cumulative HIacute. personal monitors comparable to the synthetic HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1161

TABLE 4. COPC at the Four Outdoor Fields (A, B, C, D)

Maximum Ratio to Location Number of Detected detect highest and type ﬁelds with off-gas COPC (µg/m3) background of sample elevation study

VOC Carbon disulfidea,b 0.47 2.9 B: Personal 1 No Chloromethaneb 1.7 1.4 B: Personal 1 No Cyclohexaneb 17.5 3.6 B: Personal 1 No Ethyl benzene 4.29 2.0 B: Personal 1 Yes Heptane 5.72 2.7 B: Personal 1 No Hexane 31.3 4.2 B: Personal 2 Yes Methylene chloride 14.1 12.8 B: Personal 1 Yes Methylisobutyl ketone 3.39 3.3 B: Personal 1 Yes Toluene 52.7 1.35 B: Personal 2 Yes Xylenes 14.7 2.1 B: Personal 1 Semi-VOC Targeted Benzothiazole 1.2 1.7 D: 6 inch 4 Yes PAH Acenaphthylene 6.6E-03 8.6 D: Stationary 1 NA Benz[a]anthracene 1.1E-04 3.7 B: Stationary 1 NA Benzo[a]pyrene 1.9E-04 3.8 B: Stationary 2 NA Benzo[b]fluoranthene 2.1E-04 3.0 B: Stationary 2 NA Benzo[e]pyrene 2.6E-04 4.3 B: Stationary 2 NA Benzo[ghi]perylene 1.4E-04 2.3 A: Stationary 1 NA Benzo[k]fluoranthene 8E-05 2.0 C: Stationary 1 NA Chrysene 3.4E-04 4.9 B: Stationary 2 NA Fluoranthene 6.8E-03 4.6 D: Stationary 2 NA 1-Methylnaphthalene 9.3E-03 1.3 D: Stationary 1 NA Pyrene 6.9E-03 2.2 D: Stationary 1 NA Miscellaneousc Total sum 1.33 — D: Stationary 3 NA

aSlightly higher personal monitor and much higher background detects were found at field C but that field had pesticide spraying in the background area during sampling. bThese volatile analytes were included as COPCs even though they were not detected in the laboratory off-gas studies because there was at least some evidence that they were present in field-related samples besides personal monitoring samples. cFor 93 compounds including aliphatics, hopanes, terpenes, and pristanes.

turf personal samplers. Possible reasons for Two of the specially targeted SVOC,

Downloaded by [University of Connecticut] at 07:51 29 August 2013 such detections in personal monitoring sam- benzothiazole and butylated hydroxytoluene ples are discussed in a subsequent section. In (BHT), were selected as COPC. Benzothiazole other cases, analytes detected in personal mon- was detected above background on both the itors were also found in laboratory headspace outdoor and indoor fields. The maximum studies and were higher in synthetic turf as indoor result was 11.7-fold greater than the compared to grass personal monitoring sam- maximum outdoor result, which is one of ples. These VOC are included in the COPC the more dramatic indoor/outdoor differences lists in Tables 4 and 5. It is possible that some (Figure 4). Benzothiazole was detected above percentage of the personal monitoring result in background at all fields, and results on the these cases came from the player rather than field were higher than in the personal moni- the field. Since this percent is unknown, the toring sample, an opposite trend compared to personal monitor detects were used at face the VOC. BHT is a COPC at the indoor field. value to represent what may have been com- Similar to benzothiazole, BHT was detected ing off the field for the purpose of the risk above background in all field-related samples assessment. at the indoor field, with results higher in the 1162 G. GINSBERG ET AL.

TABLE 5. COPC at the One Indoor Field (K)

Maximum Ratio on-ﬁeld detect to highest Type of COPC detect (µg/m3) background sample

VOC Acetone 92.5 1.7 Personal Carbon disulﬁdea 0.9 5.6 Stationary 6 inches, 3 ft Chloromethane 1.57 1.3 Personal Cyclohexane 10.3 2.1 Personal Ethyl benzene 4.77 2.2 Personal Heptane 10.22 4.8 Personal Hexane 11.25 1.5 Personal Methylene chloride 10.3 9.4 Personal MEK 44.2 5.6 Personal MIBK 36 35 Stationary 6 inches, 3 ft Styrene 3.53 1.4 Personal Toluene 135 3.5 Personal Xylenes 15.7 2.2 Personal Semi-VOC Targeted Benzothiazole 14 19.8 Stationary 6 inches Butylated hydroxytoluene 3.9 13.9 Stationary 3 ft PAHs Acenaphthene 1.74E-02 22.7 Stationary Acenaphthylene 6.8E-03 8.8 Stationary Fluoranthene 5.60E-03 3.8 Stationary Fluorene 5.40E-02 15 Stationary Naphthalene 1.13E-01 6.6 Stationary 1-Methylnaphthalene 1.14E-01 16.5 Stationary 2-Methylnaphthalene 6.30E-02 19.1 Stationary 2,6-Dimethylnaphthalene 2.90E-02 2.8 Stationary Phenanthrene 3.20E-02 2.4 Stationary Pyrene 1.18E-02 3.8 Stationary Miscellaneousb Total Sum 4.4 — Stationary

aMuch higher background detect at ﬁeld C but that ﬁeld had pesticide spraying in the background area during sampling. bFor 93 compounds including aliphatics, hopanes, terpenes, and pristanes.

stationary as opposed to personal monitor. BHT on any ﬁeld. Other PAHs (acenaphthene,

Downloaded by [University of Connecticut] at 07:51 29 August 2013 was not elevated at the outdoor fields. fluoranthene, pyrene) were detected above A variety of PAH were detected above background both outdoors and indoors. background and considered COPC at both Miscellaneous SVOC include a wide vari- the outdoor and indoor field. The con- ety of hopanes, pristanes, terpenes, cosines, centrations were generally low, well below and other aliphatics derived from fossil fuels 1 µg/m3. The larger multiring PAH (benzan- or of plant based origin and common in out- thracene through chrysene in Table 4) were door air (Andreou and Rapsomanikis 2009; detected in the outdoor field, while the more Schnelle-Kreis et al. 2007). These air con- volatile two-ring PAH (naphthalene and its taminants are particle-bound and, while not derivatives) were found indoors but gener- reported to be present in rubber, did show ally not outdoors (Figure 5). The one excep- higher concentration on turf than off for one tion was 1-methylnaphthalene at one out- of the SVOC on field A, one on field C, door field (field D). The naphthalene and and four on field D. The total concentra- 1-methylnaphthalene detects at the indoor tions of miscellaneous SVOC that are in excess field were by far the largest PAH detects of background concentrations are shown in HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1163

TABLE 6. Analytes Found in Personal Monitors but Excluded pyrene) was used to characterize the entire From the Risk Assessment grouping. Highest While a variety of carcinogenic and volatile personal nitrosamines were assessed in field air samples, monitor Reason detection for none were detected and nitrosamines were not Analyte (µg/m3)exclusion COPC in this risk assessment. Nitrosamines were sampled because of their use in rubber manu- 1-Ethyl-4-methylbenzene 1.37 Absent in headspace, present in grass facture and the potential that they could remain field personal in the final product. PM10 measurements were monitorsa made on the fields and at background locations 1,2,4- and 2.16 Absent in headspace, to assess the potential for crumb rubber par- 1,3,5-Trimethylbenzenes present in grass field personal ticulates to be generated by active play and monitors produce elevated breathing zone concentra- 1,2-Dichloropropane 1.14 Absent in headspace tions. However, sampling of PM10 across four Acrolein 3.89 Absent in headspace, present in grass of the five fields did not find elevated concen- field personal trations. The on-field result at each field failed monitors to exceed the range of detects found at back- Benzene 1.56 Grass field personal µ / 3 monitors not ground locations, 5–10 g m . Field C was an different than outlier with higher levels of PM10 in both the synthetic turf on-field and upwind samples (16–18 µg/m3). A personal monitors grass field just upwind of field C received pesti- Bromoform 34.8 Absent in headspace Ethyl acetate 11.87 Absent in headspace, cide spray during the beginning of the sampling present in grass event, which may have interfered with PM10 field personal and other results. Therefore, PM10 was also not monitors Propene 0.89 Absent in headspace, considered a COPC. present in grass Lead (Pb) was a target analyte because of field personal limited data in New Jersey showing elevated monitors Tetrachloroethylene 3.29 Absent in headspace Pb in synthetic grass samples, which led to Tetrahydrofuran 3.5 Absent in headspace, an investigation by the U.S. Consumer Product present in grass Safety Commission (CPSC 2009). Our bulk field personal phase lead testing from each field’s synthetic monitors Trichloroethylene 23.4 Absent in headspace, grass blades and crumb rubber were uniformly present in grass below 400 ppm, the CTDEP Remediation field personal Standard Regulation for Pb, and the point monitors

Downloaded by [University of Connecticut] at 07:51 29 August 2013 Vinyl acetate 2.95 Absent in headspace, of departure nationally for concern for hous- present in grass ing units and schools. These results were also field personal below the 300-ppm target set by the Consumer monitors Product Safety Improvement Act for Pb in aGrass field personal monitor refers to monitored play at the products intended to be used by children. The backgroung community site (field L). highest lead Pb found in any sample from the 5 fields was 271 ppm (field D). The lack of elevated Pb in our current testing suggests that if Figure 6. These analytes were combined under Pb is elevated in polyethylene synthetic grass or the COPC category of miscellaneous SVOC crumb rubber, it is not a widespread problem. in Tables 4 and 5, with the total in excess of background combined across analytes for risk assessment since there is no toxico- Risk Estimates logical basis for chemical-by-chemical analy- Figures 7 and 8 and Table 7 summarize the sis. A conservative toxicology value (RfC for risk assessment results for the four scenarios 1164 G. GINSBERG ET AL.

4.5 4 ) 3 3.5 3 2.5 2 1.5 1 ND ND ND Air Conc (ug/m 0.5 0 3 feet 3 feet 3 feet 6 inch 6 inch 6 inch Personal Personal 1 Personal 2 Personal 1 Personal 2 Personal 1 Personal 2 Community Community Background Background Background

AAAABBBBKKKKABKLL

FIGURE 2. Acrolein detects at synthetic turf fields. No detects at fields C and D. ND, not detected (color figure available online).

1.8 1.6 ) 3 1.4 1.2 1 0.8 0.6 0.4 Concentration (ug/m ND ND ND ND ND ND 0.2 0 3 feet 3 feet 3 feet 3 feet 6 inch 6 inch 6 inch 6 inch Personal Personal Personal 1 Personal 2 Personal Personal 1 Personal 2 Personal Personal 1 Personal 2 Personal Personal 1 Personal 2 Personal Community Community Background Background Background Background Background

AAAABBBBCCCCKKKKABCDKLL

FIGURE 3. Benzene detects at synthetic turf fields. No detects at field D. ND, not detected (color figure available online). Downloaded by [University of Connecticut] at 07:51 29 August 2013

FIGURE 4. Benzothiazole results across indoor and outdoor ﬁelds. ND, not detected (color ﬁgure available online). HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1165

Acenaphthene 1000 Acenaphthylene Benz(a)anthracene Benzo(a)pyrene 100 Benzo(b)fluoranthene ) 3 Benzo(e)pyrene Benzo(ghi)fluoranthene 10 Benzo(ghi)perylene Benzo(k)fluoranthene Chrysene 1 Fluoranthene Fluorene

concentration (ng/m Naphthalene 0.1 1-Methylnaphthalene 2-Methylnaphthalene 2,6-Dimethylnaphthalene 0.01 Phenanthrene Field A Field B Field C Field D Field K Pyrene

FIGURE 5. Polycyclic aromatic hydrocarbons detected above background concentration (color ﬁgure available online).

10000 ) 3 1000

100

10 Concentration (ng/m

1 Field A Field B Field C Field D Field K

FIGURE 6. Total miscellaneous SVOC detected above background (color ﬁgure available online).

1.00E−04

1.00E−05 Total Downloaded by [University of Connecticut] at 07:51 29 August 2013 1.00E−06 Methylene chloride Chloromethane 1.00E−07 Benzothiazole PAHs 1.00E−08

1.00E−09 Child outdoor Child indoor Adult outdoor Adult indoor

FIGURE 7. Cancer risk estimates from indoor and outdoor synthetic turf ﬁelds (color ﬁgure available online).

evaluated. Various VOC and SVOC contribute cumulative cancer risk found indoors for chil- to both cancer and noncancer risk estimates. dren (1.3E–06). Various analytes were detected Cancer risks are at or below de minimis (1 in a at greater concentration indoors relative to million) levels in all scenarios, with the greatest outdoors, which translated into a two to 3-fold 1166 G. GINSBERG ET AL.

1.60

1.40

1.20

1.00 Non-Cancer HI 0.80 Acute HI 0.60 Hazard index

0.40

0.20

0.00 Child outdoor Child indoor Adult outdoor Adult indoor

FIGURE 8. Hazard indices for noncancer and acute risk at synthetic turf ﬁelds (color ﬁgure available online).

TABLE 7. Summary of Artiﬁcial Turf Field Risks

Child outdoor Child indoor Adult outdoor Adult indoor

Cancer risk 5.00E-07 1.30E-06 2.90E-07 1.10E-06 Noncancer 0.05 0.42 0.04 0.28 Acute 0.35 0.9 0.23 0.6 Key analytes Cancer PAH 6.7% PAH 26% PAH 10% PAH 52% MethyleneCl 64% MethyleneCl 35% MethyleneCl 61% MethyleneCl 23% Chloro Me 28% Chloro Me 20% Chloro Me 27% Chloro Me 12.8% BenzothiaZ 2% BenzothiaZ 18% BenzothiaZ <1% BenzothiaZ 12.1% Noncancer BenzothiaZ 12% BenzothiaZ 35% BenzothiaZ 11.5% BenzothiaZ 35% Toluene 30% Toluene 20% Toluene 30% Toluene 20% Acute BenzothiaZ 12.4% BenzothiaZ 56% BenzothiaZ 12.4% BenzothiaZ 56% Toluene 8.0% Toluene 7.9% Toluene 8.0% Toluene 7.9%

Note. PAH: polycyclic aromatic hydrocarbon; Methylene Cl: methylene chloride; BenzothiaZ: benzothiazole; Chloro Me: chloromethane.

greater cancer risk indoors (Figure 7). Risk (Table 7 and Figure 8). Even when adding all estimates for children were somewhat higher HQ together, the total is still below unity. The

Downloaded by [University of Connecticut] at 07:51 29 August 2013 than adults due to their greater ventilation rate highest HI is 0.42 for children playing at the and vulnerability to mutagenic carcinogens, indoor field. None of the analytes predominate but this was partially offset by the greater with the majority of the risk spread between number of years of exposure in the adult 16 VOC and targeted SVOC. PAH contribute scenario. The greatest contribution to cancer little to the noncancer risk. The greatest per- risk at the outdoor fields was from the VOC centage contributors are benzothiazole and methylene chloride, while indoors there was toluene (Table 7). a more uniform spread of contributing ana- The acute risk estimate is below unity for all lytes, with PAH making a more prominent analytes and scenarios; this is also true when contribution (Table 7 and Figure 7). None of the individual chemical risks are totaled to a the individual contributors approached 1 in a cumulative HI (Table 7 and Figure 8). The million cancer risk. highest HI is for children at the indoor field, The chronic noncancer risk estimate is reaching a value just below unity (0.9). This below unity for all analytes in all scenarios value is driven by benzothiazole (56% of the HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1167

total), with relatively minor contributions from been evaluated. Further, the inhalation route a variety of other VOC. The benzothiazole- of exposure may be qualitatively distinct from induced acute effect of potential concern is ingestion in food. respiratory irritation. The limited inhalation data for benzothiazole indicate activity in the mouse RD50 assay, suggesting irritation potential for humans. This DISCUSSION assay has been a useful screen for assessing This risk assessment utilized conservative occupational exposure levels for respiratory screening level assumptions to assess the sam- irritants and is a way to scale the rela- pling results from four outdoor and one indoor tive potency of one chemical versus another synthetic turf field. Full-scale detections of (Bos et al., 1992). Therefore, extrapolation of analytes were used without background cor- the ratio of benzothiazole to formaldehyde rection, surrogate chemicals were used to fill RD50 results (CPSC, 1996) to an acute tar- in missing toxicity data, risks were added get concentration for benzothiazole is justifi- across chemicals regardless of target effect, able. A 10-fold uncertainty factor was added and high-end assumptions were used regarding to account for the nature of the extrapolation time spent playing on the fields. Acute risk (across species, across chemicals) and for the was evaluated along with the more traditional potential that benzothiazole may be a sensitiz- chronic risk estimates. While our calculations ing agent (Ginsberg et al. 2011). The fact that are likely to overestimate risk, the risk esti- this approach yielded a borderline acute risk mates were still uniformly at or below de for benzothiazole in combination with other minimis levels. The greatest cancer risk cal- irritants found at the indoor field (naphthalene culated was 1.3E-06 for children playing on and several VOC) indicates this to be an area of the indoor field, while the acute and chronic uncertainty. hazard indices were all below unity. What is clear is that air concentrations are The major area of uncertainty identified is considerably higher for some analytes at the with respect to the acute irritation potential at indoor field. The study team enquired to the the indoor field. The HI was near unity (0.9), building manager as to possible sources of VOC with benzothiazole the major risk driver. Of all and SVOC in the building from stored mate- the detected analytes, benzothiazole is most rials and products used. This survey failed to clearly field-related and its levels at the indoor uncover any sources that might confound the field were 12-fold higher than outdoors. The indoor air results. Thus, it was concluded that toxicity data gaps for benzothiazole are more the elevated detections came from the field numerous than actual data, and toxicity values itself. This field has a ventilation system but it

Downloaded by [University of Connecticut] at 07:51 29 August 2013 used in this assessment were based upon anal- was not turned on on the day of testing, which ogy with 2-mercaptobenzothiazole for cancer is typical of indoor synthetic turf facilities. The effects and with formaldehyde for acute effects. ventilation system is primarily in place to vent The derivation of benzothiazole potency values excess temperatures in the summertime and for acute, chronic, and carcinogenic endpoints thus not running much of the year. The day is detailed in our companion article (Ginsberg this facility was tested it was moderate summer ◦ et al. 2011). Based upon this analysis, ben- weather (outdoor temperature 75 F), so would zothiazole has conservatively been considered be unlikely to have triggered running of the a low-dose mutagenic carcinogen, chronic tox- ventilation system. After learning of our results, icant, and acute irritant. The fact that it has the management at this ﬁeld decided to vent been an approved food additive for many years the indoor air whenever the ﬁeld is in use. tends to decrease the level of concern for Aside from lack of ventilation, another rea- other benzothiazole exposures. However, the son for elevated concentrations indoors is lack amount of exposure from food and the possible of weathering. Figure 9 shows the rate of adverse health effects of that exposure have not weathering of benzothiazole and other analytes 1168 G. GINSBERG ET AL.

FIGURE 9. Decrease in chemical out-gassing from a crumb rubber sample under natural weathering conditions. Crumb rubber sample was exposed outdoors for the indicated periods of time beginning August 3, 2009. Fraction remaining at each time point was normal- ized to day 0. Standard deviations of duplicate samples are shown as error bars. Chemical abbreviations: BT, benzothiazole; 1Me-NA, 1-methylnaphthalene; 2Me-NA, 2-methylnaphthalene; NA, naphthalene; 4-t-OP, 4-tert-octylphenol; BHA, butylated hydroxyanisole. Reprinted from Li et al. (2010) with permission.

off-gassing from a new crumb rubber sample monitoring samples relative to the stationary that had undergone different times of outdoor monitors. This raises a concern that some of weathering (Li et al. 2010). Approximately 75% these detections might not be field-related. In of benzothiazole is lost from the crumb rubber particular, acrolein and benzene were detected sample within the first 2 wk of weathering, a in personal monitors at levels that might poten- factor that might make an indoor field retain tially be risk drivers but were not likely to be high concentrations of rubber-related SVOC derived from the synthetic turf because the longer than an outdoor field. grass field personal monitoring showed these While exposure to all detected COPC is analytes at comparable levels, and in the case possible, our confidence is greatest for a smaller of acrolein, it is not known to be a com- subset being field-related. That grouping is ponent of rubber. While the main source of led by benzothiazole, a compound known to human exposure to acrolein is considered to be used in rubber production. The remaining be related to cigarette smoke or combustion COPC are less specific, with many also com- sources, there are endogenous sources result- ing from background combustion sources, and ing from the processing of sugars, lipids, and some VOC may also derive from endogenous certain amino acids (Stevens and Maier 2008).

Downloaded by [University of Connecticut] at 07:51 29 August 2013 (within the body) sources and be detected in Given the volatility of acrolein, a percentage personal monitoring samples. Based upon the of endogenous formation would be expected pattern of detection and presence of labora- to be found in exhaled breath, and in fact, tory off-gas samples (Li et al. 2010; Simcox acrolein was detected in the exhaled breath et al. 2011), it appears likely that in addition to of smokers at higher concentration than in benzothiazole, detects of toluene, methyl ethyl nonsmokers (Andreoli et al. 2003). Similarly, ketone, methyl isobutyl ketone, BHT, methy- benzene was detected in the exhaled breath of lene chloride, and a variety of PAH (especially nonsmoking individuals in a number of studies the naphthalenes) were field related. That does with one study of 20 nonsmoking adults finding not imply that the entire amount detected orig- benzene in the breath of 65% of these individ- inated from the field in these cases, but this uals (Buszewski et al. 2008). Therefore, use of assumption adds a degree of conservatism to personal monitoring devices to screen for VOC the risk estimates. needs to have appropriate controls that capture An unexpected finding was the number the background coming from the equipment or of VOC that were elevated in the personal individual wearing the device. HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1169

Current Results in Relation to Prior fields to be within acceptable limits (Norwegian Studies Institute of Public Health and Radium Hospital The current field investigation and risk 2006). This conclusion encompassed acute assessment are similar in approach to several risks, although a formal assessment of acute previous assessments, the most relevant being exposures against acute inhalation benchmarks the study of three indoor synthetic turf fields was not undertaken. in Norway (NILU 2006), four outdoor synthetic The U.S. EPA performed a scoping-level turf fields studied by the U.S. EPA (2009a), and field monitoring study at four fields, one each in two outdoor synthetic turf fields in New York Georgia, Ohio, Maryland, and North Carolina, City (TRC 2009; NYSDEC 2009a). Each of these under summertime conditions in 2008 (U.S. studies used stationary monitors on or next to EPA 2009a). VOC, PM10, and metals sam- the field compared to a representative off-field ples were collected on the fields in the vicin- sample. ity of play activities at 1 m height. Upwind The Norwegian study involved an exten- background samples were also collected. VOC sive array of VOC and SVOC, including several detections on the field were low (less than specifically targeted because of their presence 1 ppb) with only one VOC (methyl isobutyl in rubber (NILU 2006). Chemical detections of ketone) considered to be a field-related detec- PAH (ng/m3 range), benzothiazole (low µg/m3 tion. PM10 resultsatonefieldwithhighplay range up to 32 µg/m3)andVOC(uptoa activity were elevated relative to background high of 85 µg/m3 for toluene) are qualita- but the results for PM10 and ambient Pb were tively and quantitatively similar to the list of low relative to National Ambient Air Quality detections in the present investigations, espe- Standards. The U.S. EPA concluded that the cially with respect to the indoor sampling (field methodologies were successful for assessing K—maximum toluene detect 135 µg/m3;max- emissions from artificial turf fields. While this imum benzothiazole detect 14 µg/m3). The study did not find any detections of health risk assessment conducted by the Norwegian concern, the conclusions are limited by its government evaluated 3 different age win- screening nature and small amount of data dows for children beginning as early as 7 yr collection. of age, and adults (Norwegian Institute of Somewhat more extensive testing was con- Public Health and Radium Hospital 2006). ducted at two outdoor New York City synthetic Their assessment encompassed inhalation as turf fields in late August and early September 2008 under warm, light to moderate wind con- well as dermal and oral exposure. Cancer risks ◦ were driven by benzene, which was detected ditions when ambient temperatures ( F) were in the upper 70s to low 80s and surface tem- in both on field and background samples with ◦ Downloaded by [University of Connecticut] at 07:51 29 August 2013 the background-corrected worst case estimate peratures on the fields were as high as 146 F 1.4 µg/m3 corresponding to 2E-06 cancer (NYSDEC 2009a). Particulate and VOC samples risk in their highest exposure scenario; this were collected at 3-ft height above the field risk was described as negligible (Norwegian and at upwind locations. VOC were also col- Institute of Public Health and Radium Hospital lected at the field surface. The fields were in 2006). Our benzene detections were of a sim- active use at the time of sampling. In addition, ilar magnitude, but since similar results were dust wipe and microvacuum samples were col- obtained between background and synthetic lected from the field. A large array of VOC, turf samples, benzene was not considered SVOC, and targeted VOC based upon a lab- a COPC. The Norway study found carcino- oratory headspace test were analyzed in the genic PAH, as exemplified by benzo[a]pyrene, samples. The vertical and horizontal gradients to be from background sources, and non- of six rubber-related analytes were analyzed to cancer risks carried a large margin of safety. determine if these fields show a measureable Therefore, the Norwegian government consid- emission (e.g., higher concentration at the sur- ered the exposures to indoor synthetic turf face than 3 ft, higher concentration on-field 1170 G. GINSBERG ET AL.

than upwind). These tests failed to find clear In agreement with previous results, ben- evidence of a field-related gradient and individ- zothiazole was the primary marker of rubber- ual VOC were generally no higher on the field related impacts on air quality. The current than upwind. An exception was benzothiazole, assessment provides a more comprehensive which had a detection of 6.5 µg/m3 on the sur- review of benzothiazole toxicology than previ- face of 1 of the fields while this analyte was ous analyses with calculations made for cancer, nondetect upwind. Risk assessment of VOC, chronic noncancer, and acute health risks for SVOC, and PM10 results failed to find elevated this analyte. These calculations suggest that health risks. A separate analysis of these fields benzothiazole is unlikely to be a significant contracted by the New York City Department contributor to cancer and chronic noncancer of Health found similarly few detections of risk at the concentrations detected, but that target analytes, and in that case, data did there is some uncertainty as to whether ben- not warrant the conduct of a risk assessment zothiazole might contribute to an acute health (TRC 2009). risk for children actively playing on poorly These prior field investigations included a ventilated indoor fields. variety of different weather conditions, field ages, type of crumb rubber, and sampling and analytical procedures. Studies did not find Limitations many detects that were clearly field-related and This investigation was established as a when they analyzed health risks, but detections screen of air quality at four outdoor fields and were low and within the general background one indoor field in Connecticut. This is a rel- for urban air. atively small number of fields and sampling The current analysis adds to this body of events. Thus, the degree to which the current research for crumb rubber fields in provid- results are representative of the remaining fields ing data for four additional outdoor fields, in Connecticut or elsewhere is unclear. This is one additional indoor field, results for per- especially the case for the one indoor field in sonal monitoring, and a formal analysis of that there was no active ventilation or open acute health risks. While personal monitoring doors or windows. These fields often get used was expected to provide data more relevant for youth soccer in colder times of the year, to actual users of the fields, the pattern of so the volatile emissions may be lower than results indicated that the personal monitors what was measured. Regarding the outdoor were likely detecting analytes coming from the fields, sampling was conducted in July 2009 sampling equipment or host and not neces- with targeted conditions being sunny, warm, sarily the field (e.g., Figure 2). Therefore, this and low wind. While this goal was accom-

Downloaded by [University of Connecticut] at 07:51 29 August 2013 aspect of the design needs to be carefully con- plished, it was not possible to capture a hot trolled, and our results point out the value day typical of summer heat waves when the of stationary monitors since they will intro- off-gassing of VOC might be maximized. Thus, duce less confounding. Our results are gen- it is possible that worst-case outdoor conditions erally consistent with previous investigations were not captured. This worst case may involve in showing low concentrations and risks in new crumb rubber, as headspace off-gas exper- outdoor fields with considerably higher detec- iments (Figure 9) indicating that outdoor weath- tions and somewhat higher risks at the indoor ering plays a major role in decreasing the field. The current assessment of acute health availability of chemicals to off-gas from crumb risks, while containing a variety of uncertain- rubber. Thus, a hot, sunny, low-wind day on a ties, adds to the existing database and demon- new artificial turf field may present the greatest strates some potential for acute irritation at exposure potential for VOC. This would only the indoor field; this potential is likely to be be a potential concern for acute health risks, as manageable by adequate ventilation at these these conditions would not last long. Given this facilities. potential and the possibility for heat stress to HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1171

compound the effects on respiration, it is pru- examined by Norway in their artificial turf field dent for towns to construct new fields in the investigation, it was described as an uncertainty cooler months to give them time to weather for which there was insufficient data. A fact before warm-weather play. However, it needs sheet by the New York State Department of to be emphasized that this is more an uncer- Environmental Conservation (DEC) (2008) dis- tainty than an actual finding, given that these cussed latex allergy from the perspective that a conditions (new crumb rubber, hot weather) California EPA study on guinea pig skin failed to were not tested. find allergic sensitization from contact with tire The small numbers of samples taken per rubber, and that they were not aware of allergic field presents an additional limitation as statis- reactions to the playing fields. A rubber indus- tical comparison between on-field and off-field try analysis suggests that latex allergy might not detections was not possible on a field-by-field be a health concern from tire-derived partic- basis. However, the combined results across ulate, in part because the way tires are made fields and background locations, in combina- is different than latex gloves and other forms tion with results from prior studies, present a of latex that are highly allergenic (Finley et al. consistent pattern of there being relatively few 2003). However, the extensive dermal contact detections at outdoor fields under the tested with crumb rubber and potential for low level conditions. PM10 exposure during active play leaves open As stated earlier, there was no attempt to the possibility of exposure to latex allergen on study the potential for ingestion of rubber- these fields. related dust from the fields by players or by While the current risk assessment evalu- young children who may be in attendance with ates various types of risk from benzothiazole parents watching the play. While the ingestion inhalation exposure, the potential for benzoth- of crumb rubber contaminants has received iazole to induce contact sensitization was not some attention in previous risk assessments evaluated and is currently unknown in rela- (California EPA 2007; Norwegian Institute of tion to these fields. There is limited information Public Health and Radium Hospital 2006), this to suggest that benzothiazole induces dermal remains an area of some uncertainty for which sensitization (Ginsberg et al. 2011). Given that a dust monitoring analysis (perhaps using vac- benzothiazole may be available for skin contact uum methods) would indicate the amount of from the crumb rubber and from ground crumb rubber contaminants available on the surface rubber dust, there is a potential basis for dermal of the fields. However, it is important to note reactions. The rate of transfer of benzothiazole that our analysis of Pb in synthetic blades and to the skin from crumb rubber is unknown but crumb rubber failed to find elevations at any of expected to be low, as benzothiazole is likely

Downloaded by [University of Connecticut] at 07:51 29 August 2013 the fields. to remain in the rubber rather than partition Another limitation is that the current inves- into skin. However, this could be facilitated by tigation did not attempt to measure latex intimate contact with the skin over prolonged antigen in the crumb rubber or in the PM10 col- periods in the presence of sweat. Given the lected from on field air samples. The release potential for exposure to sensitizing chemicals, of latex antigen from the fields via abrasion latex antigen, and benzothiazole, the possibility and release of particulate rubber dust is a that these fields may be associated with respi- theoretical concern, given that natural rubber ratory or dermal allergic reactions remains an contains this antigen and a substantial fraction uncertainty. of the population may be sensitized. Somewhat mitigating this concern is the fact that current monitoring did not detect elevated PM 10 CONCLUSIONS on the fields relative to background, suggesting that there was not a substantial particulate The current investigation was successful emission from the fields. When this issue was in detecting field-related VOC and SVOC at 1172 G. GINSBERG ET AL.

both outdoor and indoor fields. In particular, athletic fields. Report issued by Milone and benzothiazole is clearly field related and cer- McBroom, 1 December 2008. Available at tain PAH and possibly several VOC may also be http://www.miloneandmacbroom.com/Libra field related. Risk estimates were at or below ries/Documents/Evalutation_of_the_Environ de minimis levels for all endpoints for all four mental_Effects_of_Synthetic_Turf_Athletic. scenarios evaluated. The elevated exposures to sflb.ashx (accessed 11 February 2011). benzothiazole, naphthalenes, and several VOC Brown, D. 2007. Exposures to recycled rubber found at the indoor field present the most sig- tire crumbs used on synthetic turf fields, play- nificant uncertainty stemming from the current grounds and gardening mulch. Available at investigation and risk assessment. This indoor http://www.ehhi.org/turf/pr_turf_report.shtml field was not under active ventilation. Buszewski, B., Ulanowska, A., Ligor, T., While elevated risks were not found at Denderz, N., and Amann, A. 2008. Analysis of the sampled fields, the uncertainties identified exhaled breath from smokers, passive smok- earlier suggest certain measures to decrease ers and non-smokers by solid-phase microex- the potential for exposure. Indoor artificial turf traction gas chromatography/mass spectrom- fields would benefit from adequate ventilation etry. Biomed. Chromatogr. 23:551–56. while in use. Given the potential for weathering CAES (Connecticut Agricultural Experimental to reduce the off-gassing of VOC, it would be Station). 2007. Examination of crumb prudent for outdoor fields to be established in rubber produced from recycled tires. cooler months, giving them time to weather AC005—8/07. Accessed June 10, 2011. before the high heat conditions of midsum- http://www.ct.gov/caes/lib/caes/documents/ mer. Finally, any dermal or respiratory reactions publications/fact_sheets/examinationofcrumb that appear to be field related need to be rubberac005.pdf reported to medical personnel and local health California EPA/OEHHA. 2007. Evaluation authorities. of health effects of recycled waste tires in playground and track products. Prepared for the California Waste Management Board. REFERENCES January. Accessed June 10, 2011. http:// Andreou, G., and Rapsomanikis, S. 2009. www.calrecycle.ca.gov/publications/Tires/62 Origins of n-alkanes, carbonyl compounds, 206013.pdf and molecular biomarkers in atmospheric CASE (Connecticut Academy of Science and fine and coarse particles of Athens Greece. Engineering) 2010. Peer review of an eval- Sci. Total Environ. 407:5750–60. uation of the health and environmental Andreoli, R., Manini, P., Corradi, M., Mutti A., impacts associated with synthetic turf play-

Downloaded by [University of Connecticut] at 07:51 29 August 2013 and Niessen W. M. A. 2003. Determination ing fields. June 15. Accessed June 10, 2011. of patterns of biologically relevant aldehydes http://www.ctcase.org/reports/turf.pdf in exhaled breath condensate of healthy sub- Connecticut Department Environmental jects by liquid chromatography/atmospheric Protection. 2010. Artificial Turf Study. chemical ionization tandem mass spec- Leachate and Stormwater Characteristics. trometry. Rapid Commun. Mass Spectrom. Available at http://www.ct.gov/dep/lib/dep/ 17:637–45. artificialturf/dep_artificial_turf_report.pdf Bos,P.M.J.,Zwart,A.,Reuzel,P.G.J.,and (accessed 11 March 2011). Bragt, P. C. 1992. Evaluation of the sen- CPSC (U.S. Consumer Product Safety sory irritation test for the assessment of Commission). 2006. Sensory and pulmonary occupational health risk. Crit. Rev. Toxicol. irritation studies of carpet system materials 21:423–50. and their constituent chemicals. http:// Bristol, S., and McDermott, V. 2008. Evaluation www.cpsc.gov/LIBRARY/FOIA/FOIA98/os/ of the environmental effects of synthetic turf 3519926D.pdf (accessed 11 March 2011). HEALTH RISK ASSESSMENT OF SYNTHETIC TURF FIELDS 1173

CPSC (U.S. Consumer Product Safety http://ntp.niehs.nih.gov/ntp/htdocs/LT_rpts/ Commission). 2009. CPSC staff analysis tr500.pdf and assessment of synthetic turf grass blades. New York State Department of Environmental Available at http://www.cpsc.gov/library/foia/ Conservation. 2009. Assessment of chemical foia08/os/turfassessment.pdf. leaching, releases to air and temperature at Finley, B. L., Ownby, D. R., and Hays, S. M. crumb rubber infilled synthetic turf fields. 2003. Airborne tire particles in the envi- Available at http://www.dec.ny.gov/docs/ ronment: A possible asthma risk from latex materials_minerals_pdf/crumbrubfr.pdf (last proteins? Hum. Ecol. Risk Assess. 9:1505–18. accessed 26 January 2011). Ginsberg, G., Toal, B., and Kurland, T. 2011. NILU (Norwegian Institute for Air Pollution). Benzothiazole toxicity assessment in sup- 2006. Measurement of air pollution at indoor port of synthetic turf field human health artificial turf halls.NILUOR03/2006. risk assessment. J. Toxicol. Environ. Health A Accessed June 10, 2011. http://www.docs 74(17): XXX. toc.com/docs/36953595/Measurement-of- Ginsberg, G., Foos, B., Dzubow, R. B., air-pollution-in-indoor-artificial-turf-halls and Firestone, M. 2010. Options for Norwegian Institute of Public Health and incorporating children’s inhaled dose into Radium Hospital. 2006. Artificial turf human health risk assessment. Inhal. Toxicol. pitches: An assessment of the health risks for 22:627–47. football players. Accessed June 10, 2011. KEMI (Swedish Chemicals Agency). 2006. http://www.isss.de/conferences/Dresden%20 Synthetic turf from a chemical perspective—A 2006/Technical/FHI%20Engelsk.pdf statusreport. Availableathttp://www.kemi.se/ Schnelle-Kreis, J., Sklorz, M., Orasche, J., upload/Trycksaker/Pdf/PM/PM3_06_eng.pdf Stolzel, M., Peters, A., and Zimmerman, R. LeDoux, T. 2007. Preliminary assessment of the 2007. Semi volatile organic compounds in toxicity from exposure to crumb rubber: Its ambient PM2.5: Seasonal trends and daily use in playgrounds and artificial turf playing resolved source contributions. Environ. Sci. fields. NJ Department of Environmental Technol. 41:3821–28. Protection, Division of Science, Research Simcox, N., Bracker, A., Ginsberg, G., Toal, B., and Technology. Available at http://www. Golembiewski, B., Kurland, T., and Hedman, syntheticturfcouncil.org/associations/7632/ C. 2011. Synthetic turf field investigation files/NJ%20Dept.%20Environmental%20 in Connecticut. J. Toxicol. Environ. Health A Protection%206-07.pdf (accessed 11 March 74(17): XXX. 2011) Stevens, J. S., and Maier, C. S. 2008. Acrolein: Li, X., Berger, W., Musante, C., and Incorvia- Sources, metabolism and biomolecular inter-

Downloaded by [University of Connecticut] at 07:51 29 August 2013 Mattina, M. J. 2010. Characterization of sub- actions relevant to human health and dis- stances released from crumb rubber material ease. Mol. Nutr. Food Res. 52:7–25. used on artificial turf fields. Chemosphere TRC Environmental Corp. 2009. Air quality 80:275–80. survey of synthetic turf fields containing National Toxicology Program. 1992. Toxicology crumb rubber infill. TRC project no. 153896. and carcinogenesis studies of naphthalene in Accessed June 10, 2011. http://www.nyc. B6C3F1 mice (inhalation studies).Tech.rep. gov/html/doh/downloads/pdf/eode/turf_aqs_ series no. 410. Accessed June 10, 2011. report0409.pdf http://ntp.niehs.nih.gov/ntp/htdocs/LT_rpts/ U.S. Environmental Protection Agency. 2005. tr410.pdf Supplemental guidance for assessing suscep- National Toxicology Program. 2000. Toxicology tibility to early life exposure to carcinogens. and carcinogenesis studies of naphthalene EPA/630/R-03/003. Available at: http:// in F344/rats (inhalation studies).Tech.rep. cfpub.epa.gov/ncea/cfm/recordisplay.cfm? series no. 500. Accessed June 10, 2011. deid=160003 1174 G. GINSBERG ET AL.

U.S. Environmental Protection Agency. 2005. U.S. Environmental Protection Agency. 2009b. National air toxics assessment (NATA) Exposure factors handbook. 2009 Update, for 2005: Summary of results. Available external review draft. Available at: http:// at: http://www.epa.gov/ttn/atw/nata2005/ cfpub.epa.gov/ncea/cfm/recordisplay.cfm? 05pdf/sum_results.pdf (accessed 4 April deid=20563 2011). Woodruff, T. J., Axelrad, D. A., Caldwell, J., U.S. Environmental Protection Agency. 2009a. Morello-Frosch, R., and Rosenbaum, A. A scoping-level ﬁeld monitoring study of syn- 1998. Public health implications of thetic turf ﬁelds and playgrounds. EPA600/R- 1990 air toxics concentrations across 09/135 Available at: http://www.epa.gov/ the United States. Environ. Health Perspect. nerl/documents/tire_crumbs.pdf 106:245–51. Downloaded by [University of Connecticut] at 07:51 29 August 2013