Rachel's Report
October 2, 2008
Synthetic turf playing fields are expanding at a rapid pace, but
concerns about their health risks are growing as well. In recent
months, the concerns have focused on the possibility that the turf
contains toxic lead (Pb), which can have especially harmful effects on
the cognitive functioning of children. When absorbed, lead can lower
children's IQs and cause attention deficits. [1]
Questions about lead have risen with respect to both the old style
AstroTurf and the "new generation" turf. The old style turf is
basically a carpet with nylon grass fibers. It lacks the springiness
of the new generation turf, which typically uses polyethylene fibers
and includes a rubber granule infill. Advertisers say that playing on
the new turf is more like playing on natural grass.
Artificial Grass Fibers in Old Style Turf
The current concerns began with a routine state inspection. In the
summer of 2007, the New Jersey Department of Health and Senior
Services (DHSS) was investigating potential toxicants in a scrap metal
yard in the city of Newark and decided to examine the adjacent,
old
style turf field as well. Laboratory tests revealed high levels of
lead in the nylon turf fibers and in the dust resulting from the
fibers' deterioration. [2] The New Jersey DHSS concluded that the lead
didn't come from the scrap metal yard, but from the field itself. [3]
In follow up studies, the New Jersey DHSS also found high lead levels
in two other old-style turf fields in the state, one in the city of
Ewing and the other in the city of Hoboken. [4] The findings prompted
the federal Centers for Disease Control and Prevention (CDC) to issue
a June 18, 2008, health advisory, recommending precautions such as
washing hands after playing on synthetic grass fields. [5]
The New Jersey DHSS also initiated laboratory simulations to evaluate
the effects of ingesting the fibers or the fiber dust. The results
suggested that a significant portion of the lead in the fibers and
dust is dissolved in digestive
fluids. Once dissolved, some of the
lead might enter the blood and affect the central nervous system. [6]
The Synthetic Turf Council, which represents the synthetic turf
industry, questioned the actual risk, but the findings were worrisome.
[7]
Fibers in New Generation Turf
When the New Jersey findings were reported in the press, I was a
consultant to a task force considering the installation of synthetic
turf in Battery Park City in Manhattan. Some of the task force members
had read about the New Jersey findings, but they weren't concerned.
Their fields would be the new generation turf, which
tends to use polyethylene grass fibers -- not nylon -- and the New
Jersey DHSS hadn't found high levels of lead in the polyethylene
fibers it tested. [4]
Subsequently, the U.S. Consumer Product Safety Commission (CPSC)
detected moderate concentrations of lead in a small number of
samples
of new generation turf fibers. These results pertained to green
fibers, which are the most prevalent in synthetic turf products. But
manufacturers use various colors to mark field boundaries, and the
CPSC found extremely high concentrations of lead in yellow fibers.
Guive Mirfendereski, who operates the website SynTurf.org, also had
fibers tested and obtained similar results. [8] It is likely that the
lead in the fibers primarily comes from the pigments.
Nevertheless, the CPSC also evaluated the risk of ingesting the lead
in the fibers and gave the fields a clean bill of health.
Specifically, the CPSC concluded that hand contact with the fibers,
followed by hand-to-mouth contact, was unlikely to pose a danger. On
July 30, 2008, it issued a press release titled, "CPSC Staff Finds
Synthetic Turf Fields OK to
install, OK to play on." [9]
As Consumer Reports recently observed, the CPSC's conclusion is
premature. [10] For one thing, the CPSC didn't consider alternative
exposure routes such as direct swallowing or dust inhalation. In
addition, the CPSC often relied on speculation instead of collecting
relevant data. For example, it didn't gather data on the fraction of
lead in polyethylene fibers that is dissolved in the digestive tract
and might enter the blood. Finally, the CPSC used safety standards
that are probably too lax.
The question of safety standards is particularly vexing. Growing
research indicates that even low levels of lead can cause
neurocognitive damage in children. [11] It appears that no level of
lead can be considered "safe" in children's blood. But public health
agencies such as the CPSC and CDC have not adjusted their safety
standard in light of this finding. (For a fascinating
account of the
CDC's refusal to adjust its standards, see Peter Montague's article in
the July 26, 2007 issue of Rachel's Democracy and Health News
(#917).)
In September, 2008, the California attorney general joined legal
actions by the Center for Environmental Health (Oakland, Calif)
against several synthetic turf companies. The plaintiffs have argued
that their test results reveal high lead levels in some turf fields,
although they haven't made details of their results public. [12]
Rubber Granules in New Generation Turf
Most brands of synthetic turf include tons of tiny (0.5 to 3 mm)
rubber granules that lie between the artificial grass fibers. The
rubber granules, which are usually made from scrap
tires, contribute
to the spring one feels when running on the turf. This springiness is
very popular, but the rubber granules, like the artificial grass
fibers, might also contain lead and other toxic chemicals that can be
absorbed into the body through exposure routes such as ingestion.
When considering ingestion -- whether it's the ingestion of fibers or
rubber granules -- I worry most about the infants and toddlers who
play on the turf while their caretakers watch the games from the
sidelines. Children this age are of special concern because they try
to put almost everything they can pick up into their mouths. And while
they might pick up some of the fibers that come loose as a field ages,
the possibility of picking up rubber granules is greater. As soon as a
new field is ready for play, the granules are loose and abundant.
What's more, the granules stick to athletes' clothes and get into
their shoes,
often spilling onto the floor when they take off their
shoes at home. So infants and toddlers are exposed to the granules
when they play on the floor at home, too.
Several research groups, including the Rochesterians Against the
Misuse of Pesticides and Jim Zhang's team at Rutgers University, have
gained information on the concentrations of lead in the rubber
granules. The results have been very consistent; concentrations seem
to range from about 3 to 67 mg/kg [milligrams per kilogram] lead.
[13-16] Although these values are below the conventional 400 mg/kg
safety standard for humans in residential environments, we should bear
in mind that even low concentrations of lead can cause neurocognitive
damage in children.
Bioaccessibility
A key question at this point is, if new generation fibers or rubber
granules are ingested, what fraction of the lead in them is
bioaccessible? That is, what fraction of
the lead dissolves in human
digestive fluids, making it available for transport out of the
digestive tract into to the blood and the rest of the body?
A recent small-scale study by Jim Zhang, I-K Han, Lin Zhang and W.
Crain [16] simulated digestive tract absorption of lead in a sample of
polyethylene fibers. Mimicking the digestive process, the study
examined absorption in synthetic saliva, synthetic gastric (stomach)
fluid, and synthetic intestinal fluid, in that order. No lead
dissolved in the saliva, but 34.6% and 54.0% of the lead dissolved in
the gastric and intestinal fluids, respectively. These are sizeable
fractions. If replicated, the results suggest that ingestion of fiber
material can have significant consequences.
The study also examined the bioacessibility of lead in rubber
granules. In the two samples tested, 24.7% and 44.2% of the lead
dissolved in synthetic gastric fluids. The researchers
didn't find
additional dissolution of lead in synthetic intestinal fluids, but the
fractions in the gastric fluids are substantial.
Summary
After high levels of lead were detected in an old synthetic turf field
in Newark, New Jersey, further research suggested that high levels of
lead were present in other old style artificial turf fields.
Researchers have sometimes found lead in new generation turf fibers as
well. These concentrations have been extremely high in yellow fibers
that mark field boundaries, but lead has sometimes showed up in the
more common green fibers, too. In addition, low-to-moderate levels of
lead have consistently been detected in the new generation turf's
rubber granules.
Because even low levels of lead can harm children's neurocognitive
development, it's important to know the lead's bioaccessibility -- the
fractions of lead in turf materials that can be dissolved in
digestive
fluids. Initial studies suggest that the lead in the old style turf
fibers, as well as the lead in the new generation turf fibers and
rubber granules, does dissolve in synthetic digestive fluids. The
results suggest that researchers take a closer look at the possibility
that children and athletes might ingest synthetic turf materials and
that the lead in the materials is absorbed in the digestive tract and
enters the blood.
==============
* William Crain is a professor of psychology at The City College of
New York. Billcrain@aol.com Through earlier articles in Rachel's
Democracy & Health News (#873 & #902) Dr. Crain was among the first to
alert the U.S public to possible toxicants in synthetic turf.
References
[1] Landrigan,
P. J. Environmental Threats to Children's Health in
America's Schools: The Case for Prevention. Testimony to the
Committee
on Environment and Public Works, United States Senate, Oct. 1, 2002.
[2] New Jersey Department of Health and Senior Services. Updated Lead
and Artificial Turf Fact Sheet, August 2008.
[3] New Jersey Department of Health and Senior Services. New Jersey
Investigation of Artificial Turf and Human Health Concerns, April
2008.
[4] New Jersey Department of Health and Senior Services. DHSS Calls
for Federal
Action on Potential Lead Health Hazard Posed by Artificial
Turf, April 14, 2008. http://www.state.nj.us/cgi-bin/dhss/njnewsl
ine/view_article.pl?id=3174
[5] Centers for Disease Control and Prevention. CDC Health Advisory:
Potential Exposure to Lead in Artificial Turf: Public Health Issues,
Actions, and Recommendations, June 18, 2008. http://www.cdc.gov/n
ceh/lead/artificialturf.htm
[6] NBC. N.J. Agency Releases Toxic Turf Report, June 3, 2008. ht
tp://www.nbc10.com/health/16477245/detail.html
[7] Synthetic Turf Council. Safety of
Synthetic Turf Validated by NJ
Test Results, June 5, 2008. www.syntheticturfcouncil.org
[8] Mirfendereski, G. Turf Fibers from Five Venues in Boston Area
Contained Excessive Amounts of Lead. SynTurf.org, Lead, No. 16,
September, 2008.
[9] U.S. Consumer Product Safety Commission. CPSC Staff Finds
Synthetic Turf Fields OK to Install, OK to Play on, July 30, 2008. ht
tp://www.cpsc.gov/cpscpub/prerel/prhtml08/08348.html
[10] Federal Agencies at Odds over Artificial Turf Recommendations,
Consumer Reports.org September 5, 2008. http://blogs.consumerrep
orts.org/safety/2008/09/lead-in-turf.html
[11] Canfield, R.L., Henderson, C.R., Cory-Slechta, D.A., Cox,
C.,Jusko, T.A., and Lanphear, B.P. Intellectual Impairment in Children
with Blood Lead concentrations Below 10 Micrograms per Deciliter. New
England Journal of Medicine, 348, 2003, pp. 1417-1526.
[12] Center for Environmental Health. More Artificial Turf Found with
Lead, as California Attorney files lawsuits, Sept. 2, 2008.
[13] Plesser, T. S. W., and O. J. Lund. Potential Health
and
Environmental Effects Linked to Artificial Turf Systems -- Final
Report. Norwegian Building Research Institute (report to the
Norwegian Football Association), 2004.
[14] Rochesterians Against the Misuse of Pesticides. Synthetic Turf
Chemicals, 2007.
[15] The City of New York, Department of Health and Mental Hygiene.
Report: Lead Hazard Risk Assessment of Synthetic Turf Playing Fields,
April 15, 2008.
[16] Zhang, J., I-K Han, L. Zhang, and W. Crain. Hazardous Chemicals
in Synthetic Turf Materials
and their Bioaccessibility in Digestive
Fluids. Journal of Exposure Science & Environmental Epidemiology, Vol.
18, No. 6, November/December 2008. Published by the journal online
August 27, 2008.
October 2, 2008
Synthetic turf playing fields are expanding at a rapid pace, but
concerns about their health risks are growing as well. In recent
months, the concerns have focused on the possibility that the turf
contains toxic lead (Pb), which can have especially harmful effects on
the cognitive functioning of children. When absorbed, lead can lower
children's IQs and cause attention deficits. [1]
Questions about lead have risen with respect to both the old style
AstroTurf and the "new generation" turf. The old style turf is
basically a carpet with nylon grass fibers. It lacks the springiness
of the new generation turf, which typically uses polyethylene fibers
and includes a rubber granule infill. Advertisers say that playing on
the new turf is more like playing on natural grass.
Artificial Grass Fibers in Old Style Turf
The current concerns began with a routine state inspection. In the
summer of 2007, the New Jersey Department of Health and Senior
Services (DHSS) was investigating potential toxicants in a scrap metal
yard in the city of Newark and decided to examine the adjacent,
old
style turf field as well. Laboratory tests revealed high levels of
lead in the nylon turf fibers and in the dust resulting from the
fibers' deterioration. [2] The New Jersey DHSS concluded that the lead
didn't come from the scrap metal yard, but from the field itself. [3]
In follow up studies, the New Jersey DHSS also found high lead levels
in two other old-style turf fields in the state, one in the city of
Ewing and the other in the city of Hoboken. [4] The findings prompted
the federal Centers for Disease Control and Prevention (CDC) to issue
a June 18, 2008, health advisory, recommending precautions such as
washing hands after playing on synthetic grass fields. [5]
The New Jersey DHSS also initiated laboratory simulations to evaluate
the effects of ingesting the fibers or the fiber dust. The results
suggested that a significant portion of the lead in the fibers and
dust is dissolved in digestive
fluids. Once dissolved, some of the
lead might enter the blood and affect the central nervous system. [6]
The Synthetic Turf Council, which represents the synthetic turf
industry, questioned the actual risk, but the findings were worrisome.
[7]
Fibers in New Generation Turf
When the New Jersey findings were reported in the press, I was a
consultant to a task force considering the installation of synthetic
turf in Battery Park City in Manhattan. Some of the task force members
had read about the New Jersey findings, but they weren't concerned.
Their fields would be the new generation turf, which
tends to use polyethylene grass fibers -- not nylon -- and the New
Jersey DHSS hadn't found high levels of lead in the polyethylene
fibers it tested. [4]
Subsequently, the U.S. Consumer Product Safety Commission (CPSC)
detected moderate concentrations of lead in a small number of
samples
of new generation turf fibers. These results pertained to green
fibers, which are the most prevalent in synthetic turf products. But
manufacturers use various colors to mark field boundaries, and the
CPSC found extremely high concentrations of lead in yellow fibers.
Guive Mirfendereski, who operates the website SynTurf.org, also had
fibers tested and obtained similar results. [8] It is likely that the
lead in the fibers primarily comes from the pigments.
Nevertheless, the CPSC also evaluated the risk of ingesting the lead
in the fibers and gave the fields a clean bill of health.
Specifically, the CPSC concluded that hand contact with the fibers,
followed by hand-to-mouth contact, was unlikely to pose a danger. On
July 30, 2008, it issued a press release titled, "CPSC Staff Finds
Synthetic Turf Fields OK to
install, OK to play on." [9]
As Consumer Reports recently observed, the CPSC's conclusion is
premature. [10] For one thing, the CPSC didn't consider alternative
exposure routes such as direct swallowing or dust inhalation. In
addition, the CPSC often relied on speculation instead of collecting
relevant data. For example, it didn't gather data on the fraction of
lead in polyethylene fibers that is dissolved in the digestive tract
and might enter the blood. Finally, the CPSC used safety standards
that are probably too lax.
The question of safety standards is particularly vexing. Growing
research indicates that even low levels of lead can cause
neurocognitive damage in children. [11] It appears that no level of
lead can be considered "safe" in children's blood. But public health
agencies such as the CPSC and CDC have not adjusted their safety
standard in light of this finding. (For a fascinating
account of the
CDC's refusal to adjust its standards, see Peter Montague's article in
the July 26, 2007 issue of Rachel's Democracy and Health News
(#917).)
In September, 2008, the California attorney general joined legal
actions by the Center for Environmental Health (Oakland, Calif)
against several synthetic turf companies. The plaintiffs have argued
that their test results reveal high lead levels in some turf fields,
although they haven't made details of their results public. [12]
Rubber Granules in New Generation Turf
Most brands of synthetic turf include tons of tiny (0.5 to 3 mm)
rubber granules that lie between the artificial grass fibers. The
rubber granules, which are usually made from scrap
tires, contribute
to the spring one feels when running on the turf. This springiness is
very popular, but the rubber granules, like the artificial grass
fibers, might also contain lead and other toxic chemicals that can be
absorbed into the body through exposure routes such as ingestion.
When considering ingestion -- whether it's the ingestion of fibers or
rubber granules -- I worry most about the infants and toddlers who
play on the turf while their caretakers watch the games from the
sidelines. Children this age are of special concern because they try
to put almost everything they can pick up into their mouths. And while
they might pick up some of the fibers that come loose as a field ages,
the possibility of picking up rubber granules is greater. As soon as a
new field is ready for play, the granules are loose and abundant.
What's more, the granules stick to athletes' clothes and get into
their shoes,
often spilling onto the floor when they take off their
shoes at home. So infants and toddlers are exposed to the granules
when they play on the floor at home, too.
Several research groups, including the Rochesterians Against the
Misuse of Pesticides and Jim Zhang's team at Rutgers University, have
gained information on the concentrations of lead in the rubber
granules. The results have been very consistent; concentrations seem
to range from about 3 to 67 mg/kg [milligrams per kilogram] lead.
[13-16] Although these values are below the conventional 400 mg/kg
safety standard for humans in residential environments, we should bear
in mind that even low concentrations of lead can cause neurocognitive
damage in children.
Bioaccessibility
A key question at this point is, if new generation fibers or rubber
granules are ingested, what fraction of the lead in them is
bioaccessible? That is, what fraction of
the lead dissolves in human
digestive fluids, making it available for transport out of the
digestive tract into to the blood and the rest of the body?
A recent small-scale study by Jim Zhang, I-K Han, Lin Zhang and W.
Crain [16] simulated digestive tract absorption of lead in a sample of
polyethylene fibers. Mimicking the digestive process, the study
examined absorption in synthetic saliva, synthetic gastric (stomach)
fluid, and synthetic intestinal fluid, in that order. No lead
dissolved in the saliva, but 34.6% and 54.0% of the lead dissolved in
the gastric and intestinal fluids, respectively. These are sizeable
fractions. If replicated, the results suggest that ingestion of fiber
material can have significant consequences.
The study also examined the bioacessibility of lead in rubber
granules. In the two samples tested, 24.7% and 44.2% of the lead
dissolved in synthetic gastric fluids. The researchers
didn't find
additional dissolution of lead in synthetic intestinal fluids, but the
fractions in the gastric fluids are substantial.
Summary
After high levels of lead were detected in an old synthetic turf field
in Newark, New Jersey, further research suggested that high levels of
lead were present in other old style artificial turf fields.
Researchers have sometimes found lead in new generation turf fibers as
well. These concentrations have been extremely high in yellow fibers
that mark field boundaries, but lead has sometimes showed up in the
more common green fibers, too. In addition, low-to-moderate levels of
lead have consistently been detected in the new generation turf's
rubber granules.
Because even low levels of lead can harm children's neurocognitive
development, it's important to know the lead's bioaccessibility -- the
fractions of lead in turf materials that can be dissolved in
digestive
fluids. Initial studies suggest that the lead in the old style turf
fibers, as well as the lead in the new generation turf fibers and
rubber granules, does dissolve in synthetic digestive fluids. The
results suggest that researchers take a closer look at the possibility
that children and athletes might ingest synthetic turf materials and
that the lead in the materials is absorbed in the digestive tract and
enters the blood.
==============
* William Crain is a professor of psychology at The City College of
New York. Billcrain@aol.com Through earlier articles in Rachel's
Democracy & Health News (#873 & #902) Dr. Crain was among the first to
alert the U.S public to possible toxicants in synthetic turf.
References
[1] Landrigan,
P. J. Environmental Threats to Children's Health in
America's Schools: The Case for Prevention. Testimony to the
Committee
on Environment and Public Works, United States Senate, Oct. 1, 2002.
[2] New Jersey Department of Health and Senior Services. Updated Lead
and Artificial Turf Fact Sheet, August 2008.
[3] New Jersey Department of Health and Senior Services. New Jersey
Investigation of Artificial Turf and Human Health Concerns, April
2008.
[4] New Jersey Department of Health and Senior Services. DHSS Calls
for Federal
Action on Potential Lead Health Hazard Posed by Artificial
Turf, April 14, 2008. http://www.state.nj.us/cgi-bin/dhss/njnewsl
ine/view_article.pl?id=3174
[5] Centers for Disease Control and Prevention. CDC Health Advisory:
Potential Exposure to Lead in Artificial Turf: Public Health Issues,
Actions, and Recommendations, June 18, 2008. http://www.cdc.gov/n
ceh/lead/artificialturf.htm
[6] NBC. N.J. Agency Releases Toxic Turf Report, June 3, 2008. ht
tp://www.nbc10.com/health/16477245/detail.html
[7] Synthetic Turf Council. Safety of
Synthetic Turf Validated by NJ
Test Results, June 5, 2008. www.syntheticturfcouncil.org
[8] Mirfendereski, G. Turf Fibers from Five Venues in Boston Area
Contained Excessive Amounts of Lead. SynTurf.org, Lead, No. 16,
September, 2008.
[9] U.S. Consumer Product Safety Commission. CPSC Staff Finds
Synthetic Turf Fields OK to Install, OK to Play on, July 30, 2008. ht
tp://www.cpsc.gov/cpscpub/prerel/prhtml08/08348.html
[10] Federal Agencies at Odds over Artificial Turf Recommendations,
Consumer Reports.org September 5, 2008. http://blogs.consumerrep
orts.org/safety/2008/09/lead-in-turf.html
[11] Canfield, R.L., Henderson, C.R., Cory-Slechta, D.A., Cox,
C.,Jusko, T.A., and Lanphear, B.P. Intellectual Impairment in Children
with Blood Lead concentrations Below 10 Micrograms per Deciliter. New
England Journal of Medicine, 348, 2003, pp. 1417-1526.
[12] Center for Environmental Health. More Artificial Turf Found with
Lead, as California Attorney files lawsuits, Sept. 2, 2008.
[13] Plesser, T. S. W., and O. J. Lund. Potential Health
and
Environmental Effects Linked to Artificial Turf Systems -- Final
Report. Norwegian Building Research Institute (report to the
Norwegian Football Association), 2004.
[14] Rochesterians Against the Misuse of Pesticides. Synthetic Turf
Chemicals, 2007.
[15] The City of New York, Department of Health and Mental Hygiene.
Report: Lead Hazard Risk Assessment of Synthetic Turf Playing Fields,
April 15, 2008.
[16] Zhang, J., I-K Han, L. Zhang, and W. Crain. Hazardous Chemicals
in Synthetic Turf Materials
and their Bioaccessibility in Digestive
Fluids. Journal of Exposure Science & Environmental Epidemiology, Vol.
18, No. 6, November/December 2008. Published by the journal online
August 27, 2008.
Posts
