science in ACTION

BUILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS

A

HUMAN HEALTH
RESEARCH PROGRAM
www.epa.gov/ord

RESEARCH MODELS ESTIMATE EXPOSURE TO CHROMATED
COPPER ARSENATE (CCA) FROM PLAYSETS AND DECKS

Issue:

Little is known about the potential
health risks to young children who
play on or around wooden structures
treated with a chemical preservative
known as Chromated Copper Arsenate
(CCA). CCA-treated wood is most
commonly used in outdoor settings
for decks, walkways, fences, gazebos,
boat docks, and playground equip-
ment to protect wood from dry rot,
fungi, molds, termites, and other pests.
The compound contains chromium,
copper, and arsenic. Arsenic is a known
carcinogen that has been shown to
increase the risk of certain types of
cancer. However, information is needed
on real-world exposures to estimate
potential health risks.

Science Objective:

To understand the extent to which
children are exposed to arsenic and
chromium while playing on or around
CCA-treated playground equipment
and residential decks, scientists from
the U.S. Environmental Protection
Agency's Office of Research and Devel-
opment used a simulation model to
predict human exposure. The Stochastic
Human Exposure and Dose Simulation
model for wood preservatives (SHEDS-
Wood) is a probabilistic computer

model which allows researchers to esti-
mate exposure from skin contact with
treated wood and nearby soil, and from
ingesting wood residues and soil around
playsets and decks.

The results have shown that children
are exposed to CCA chemicals the
most when they put their hands in their
mouths after playing on CCA-treated
wood. The research also showed that
there are several variables that impact
exposure the most including: 1) the ease
with which residue on the wood surface
can be transferred to children's skin,

2)	the amount of residue on the wood,

3)	the surface area of the child's hands
that are mouthed, 4) the amount of time
a child plays on or around treated play-
sets, and 5) how often the child's hands
are washed.

Application and Impact:

The SHEDS-Wood model exposure
estimates are being used in EPA's risk
assessment for CCA. As a result of
this research, EPA has the data needed
to advise the public on how to limit
children's exposure. In addition, the
findings are informing overall risk
management strategies and providing
the science needed to make decisions

regarding re-registration eligibility
for CCA?

ORD is conducting additional studies
to evaluate the effectiveness of different
wood sealants on reducing arsenic resi-
dues in treated wood and surrounding
soil.

REFERENCES:

Zartarian, V.G.; Xue, J.; Ozkaynak, H.A. ; Dang,
W.; Glen, G.; Smith, L.; and Stallings, C. A Probabi-
listic exposure assessment for children who contact
CCA-treated playsets and decks using the stochastic
human exposure and dose simulation model for the
wood preservative scenario (SHEDS-WOOD), U.S.
Environmental Protection Agency, Washington, DC,
EPA/600/X-05/009.

Zartarian,V.; Xue, J.; Ozkaynak, H.; Dang, W.; Glen, G;
Smith, L.; Stallings, C. A probabilistic arsenic exposure
assessment for children who contact CCA-treated play-
sets and decks, Part 1: model methodology, variability
results, and model evaluation. Risk Analysis 2006, Vol.
26, No. 2,515-531.

Xue, J; Zartarian, V.; Ozkaynak, H.; Dang, W.; Glen,
G; Smith, L.; Stallings, C. A. Probabilistic arsenic ex-
posure assessment for children who contact chromated
copper arsenate (CCA)-treated playsets
and decks, Part 2: sensitivity and uncertainty analyses.
Risk Analysis 2006, Vol. 26, No. 2, 533-541.

CONTACT:

Valerie G. Zartarian, Ph.D., EPA's Office of Research
and Development, 617-918-1541, zartarian.valerie@
epa.gov

U.S. Environmental Protection Agency

Office of Research and Development

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