Recent reports associated with high levels of lead in artificial turf can be alarming at first glance. However, simply delivered, FieldTurf is safe and science is there to prove it. Let's take a look at some of the extensive toxicology, testing, research, and research support reports.
1. History
Synthetic turf, and always been safe. For more than 40 years of surveillance of the EPA and OSHA-regulated production, there is no scientific or medical evidence that synthetic turf represents human health or the environmental risk of lead (or any other material used in our products). Although in 2006 there were more than 40,000 cases of elevated levels of lead in the blood of children, there was not a single case caused by synthetic turf, and there was not a single case because synthetic turf was introduced to the US market more than 40 years ago.
Lead chromate is a stable compound that was widely used by yarn manufacturers until 2002 in the form of chrome yellow to create a beautiful yarn that would not leach out or “bleed”.
Dr. Davis Lee, Ph.D., Synthetic Organic Chemistry, executive director at a residence in Georgia, Polytechnic Institute of Technology, textile and fiber engineering, said: “If the green field of synthetic turf containing lead chromate is still green, then lead chroma still in yarn. If Yellow Chromat disappears, the field is likely to be blue. ”
Lead chromate yarn was used (and is still) in commercial and commercial carpet, as well as in synthetic turf. The chemistry of lead chromate is completely different from lead carbonate, which was previously used in household paint.
“Lead chromate is stable when encapsulated in the fiber into which it is extruded. Being encapsulated in fiber, lead in lead chromate is not readily available for bioavailability, which means that even if the thread breaks down, lead in a complex compound that is chromatite of lead is not absorbed by the body, ”says a clinical and forensic toxicologist, Dr. David Black, PhD, Aegis Sciences Corporation.
Lead chromate was chosen for use in the carpet industry because chemists and toxicologists consider it a safe compound when encapsulated in extruded yarn.
Yarn manufacturers began to switch to alternative pigments in the late 1990s due to new European waste management regulations for the disposal of heavy metals. According to Dr. Lee, “if synthetic yarns containing lead chromate will burn, lead in lead chromate may be emitted into the atmosphere.”
Despite the fact that there are no similar rules for the removal of carpet containing lead chromate in the United States, almost all synthetic turf was practically free of lead by about 2003. It is important to note that there have never been any health problems compared to chromium in synthetic turf in the United States or in Europe.
Until recently, lead chromatite was used in bright yellow and red tones in some applications of the FieldTurf logo, and in some cases in the pigment used in the yellow thread that forms lines on some of the FieldTurf football fields. Despite the fact that the use of lead chromate in these applications is absolutely safe, we abandoned the use of lead chromate to eliminate confusion with our customers regarding product safety.
2 - Key findings
Lead chromate has been used in a number of synthetic turf fields to prolong the life of its color fastness. Testing three fields in New Jersey with elevated levels of lead, NJDHSS focused on the bioavailability of synthetic turf, which it defines as the “fraction of the substance in the material that is soluble and available for absorption” by the body. The results confirmed the position of the Synthetic Lawn Council, based on scientific and expert opinion, that the extremely low bioavailability of chromate prevents its easy absorption by the human body.
Of its tests, NJDHSS reported that the amount of lead chromate contained in the fibers of the three fields available for absorption in the intestine, where food products modified by stomach acid are absorbed by blood and lymphatic systems, vary from 2.5% to 11%. We used the most extreme scenario - 11% to calculate the amount of turf that would have to be swallowed up to equal the federal standard of 600 parts per million. In practice, it is almost impossible for a child to be at risk from synthetic turf:
According to the calculations made by the forensic toxicologist Dr. David Black, a 50-pound child had to swallow more than 100 pounds. synthetic turf to be in danger of absorbing sufficiently lead to an equal minimum threshold for elevated levels of lead in the blood.
The guidance of the Consumer Product Safety Commission states that young children "should not chronically swallow more than 15 micrograms of lead per day from consumer products." Considering these test results in perspective, polymer and fiber engineer, Dr. Davis Lee, calculated that a child playing three New Jersey would have to wipe his fingers on peat and put them in his mouth 750 times a day to get enough results. equal to the CPSC threshold.
Dr. David Black conducted the same tests as NJDHSS using the same protocol at the end of May, which showed an average bioavailability of 4%. The results of the two tests are similar and confirm the safety of synthetic turf, including synthetic turf NJDHSS, reportedly contain lead chromate concentrations from 3,400 to 4,700 ppm.
3 - Facts
o Lead is not leached from synthetic turf.
o The bioavailability of lead pigment is extremely low.
o Ironbound dust from Lead (NJ) has been tested and is not a hazard for inhalation.
o Ironbound (NJ) children with regular exposure to artificial turf test
o A worker exposed to sod and particles for 30 years is normalizing.
o Even assuming that bioavailability is 50%, the amount of swallowed sod, which should pose a risk, is absurdly unrealistic.
The hazard potential is determined by several factors, including bioavailability, the proportion of the chemical that is actually absorbed.
The city of Newark conducted blood testing for children who played on the field. According to the Deputy State Commissioner of New Jersey and the state epidemiologist Dr. Eddie Bresnitsa, the results concluded that children have blood lead levels equal to or less than those tested in other parts of New Jersey that were not exposed to other fields of synthetic turf. Therefore, the Ironbound field did not lead to an increase in lead levels in children from the Ironbound area.
Synthetic turf fields in Old Tappans and DeMarray High Schools, which were initially closed, were selected on June 6, 2008. The test revealed lead in green turf fiber at concentrations of 4000 mg / kg (Old Tappan field) and 6300 mg / kg (Demarest field).
However, when the Dust Wipe was sampled at the above-mentioned Northern Valley (Old Tappan and Demarest) deposits in New Jersey, the wipe test results gave results between 10-35 µg / wipe, which falls below EPA guidelines for floor dust ( 40 µg) and interior window sills (250 µg).
Both fields were subsequently reopened.
4 - Wipe Testing, Explanation
Hysteria can be attributed to incorrect testing methods. The test that was carried out, which produces "high levels of lead," is one that is carried out to determine the chemical composition of the fiber. Simply put, it does not evaluate the bioavailability of potential health effects.
In this method, which is the standard of the Environmental Protection Agency (EPA) for hospitals and schools, the known surface area (1 square foot) of the field is wiped in both directions (up and down, back and forth) without lead to wipe. Wiping is then analyzed for total lead in the laboratory. This will give lead microgram results of lead per square foot (µg / ft2). This result can be compared with the standard EPA and HUD for dust removal 40 µg / ft2. It should be emphasized that even this comparison is conservative, that is, a likely overestimation of risk. The reason is that the dust collection standard is based on the daily one-time exposure of young children in their homes, while the impact on the ground will be mainly in older children and with less frequency.
5 - What the experts say
US Consumer Product Safety Commission
“There is no indication that the impact of the turf can cause any harm. We do not recommend at all [that] communities are closing their playing fields. ”
Center for Disease Control (CDC)
"FieldTurf field testing consistently showed 10-20 ppms or less than 5% of the lead level, which was considered problematic."
"No cases of elevated levels of lead in the blood of children are associated with artificial turf on athletic fields in New Jersey and elsewhere."
New York City Department of Health and Mental Health
“Based on the existing HUD and EPA guidelines, the risk assessment of lead in these four DPR synthetic turf deposits revealed no lead hazards.
Toxicologist Barbara D. Beck
“When interpreting the health risks from these results, it is important to recognize that people do not ingest the actual sod fibers. The 400 mg / kg NJ and EPA standards in soil are based on the assumption that young children can take approximately 100 mg. Thus, comparing lead concentrations in sod fiber with acceptable lead concentrations in soil is not an accurate way to assess the risk to human health from lead exposure. turf fibers and will probably overestimate the risk, because the turf fiber is unlikely to be absorbed (if at all) to the same extent as lead in the soil.
The best way to evaluate the effect of lead on synthetic sod fields is to evaluate the dust present on the surface of the field. When people play on the field, they can get dust on their hands or other bare skin and put dust in their mouth through normal manual activities. Thus, the main pathway we consider is dust intake. Lead has no noticeable absorption through the skin, and it is expected that the inhalation of dust from the field will be minimal, since any dust is likely to stick to the sod or rubber crumb fiber, rather than getting into the air. ”
(Dr. Beck is a professor of toxicology at Harvard, a former head of the department of aerotoxicity in the EPA Region I, a member of the Interdisciplinary Health Programs at the Harvard School of Public Health)
New Jersey Department of Health
The following is an excerpt from an article that describes events related to the closure of the artificial Montville sod field after the first test revealed 852 ppm of lead — more than twice the standard safe standard of 400 mg / kg. However, after testing the problem, the field was reopened ...
Montville approved the use of the deposit after the last lead test - Daily Record (May 8, 2008)
Patrick Gilmette, representative of PMK, explained at a meeting on Wednesday that the levels of lead found were isolated from the main sod samples and did not appear in dust, napkins and artificial grass blades taken from the field.
“In other words, lead is encapsulated in the fibers inside the sod, and not leached to the surface to get inside,” said Gilmette.
Head of the village health service, John Wozniak, also received an e-mail on Wednesday from James Brownlee, the state director of consumer care and environmental issues. Brownlee confirmed negative results from fiber samples, dust and rubbing, as discussed with Wozniak, in an email.
But Brownlee recommended that the village stop watering the fields in order to limit the dust, in the light of negative results. He also noted that if the matrix that binds the turf does not collapse, watering the fields is optional.
“My recommendation would be for only field managers to control each area and look at the potential results of degradation that could lead to matrix material becoming available,” wrote Brownlee.
Based on the recommendation of the state, the committee voted to reopen the fields without restriction.
6 - New York City Department of Health and Mental Hygiene
Lead risk assessments were conducted at four sites of DPR synthetic turf from 3 to 11 August to 3/12/08 by the Department of Health and Mental Hygiene (DOHMH). Risk assessments were carried out in accordance with the Guidelines for Lead Assessment and Control Based on Hazardous Lead Housing in Residential Buildings (HUD Guidelines) of the United States Department of Housing and Urban Development (HUD) Environment Assistant Risk. Risk assessments included a visual inspection of each site and the collection of environmental samples for lead in dust, bare soil, and degraded paint.
Applicable rules and recommendations
To determine the bioavailability of encapsulated lead in the fields, the following strict test method was used:
o EPA 40 CFR-745.65 (b) determines the risk of dust entering as surface dust in a dwelling or a room occupied by a child, which contains lead concentrations equal to or greater than 40 µg / ft2 on floors or 250 µg / ft2 on interior sills wipe samples. All wiping dust samples were compared to an EPA limit of 40 µg / ft2 on floors.
Based on existing HUD and EPA guidelines, risk assessments for lead risk in these four DPR synthetic turf deposits revealed no lead hazards. Some examples have shown that the presence of lead in synthetic carpet fibers in the fields on West 27th Street and 10th Avenue, West 103rd Street and Riverside Drive, as well as on 120th East Street and Park Avenue.
NOTE. Although the total lead concentration in the turf fiber exceeded the soil criteria, New York concluded that due to the low lead content in dust, none of the four fields tested was dangerous for lead.
7 - Field trials in the North Valley
Synthetic turf fields in the Old Tappanov and Demarray secondary schools were selected on June 6, 2008. The test revealed lead in green turf fiber at concentrations of 4000 mg / kg (old Tappan field) and 6300 mg / kg (Demarest field),
However, when the Dust Wipe was sampled at the above North Valley deposits (Old Tappan and Demarest) in New Jersey, the wipe test results gave results from 10 to 35 µg / wipe that go below the EPA directive for Dust on Floors ( 40 µg) and interior window sills (250 µg).
