oEPA	Technical Fact Sheet-
United States	t	t
Polybrominated Diphenyl Ethers
(PBDEs)
November 2017
TECHNICAL FACT SHEET - PBDEs
Introduction
This fact sheet, developed by the U.S. Environmental Protection Agency
(EPA) Federal Facilities Restoration and Reuse Office (FFRRO), provides
a summary of the contaminant groups polybrominated diphenyl ethers
(PBDEs), including physical and chemical properties; environmental and
health impacts; existing federal and state guidelines; detection and
treatment methods; and additional sources of information. This fact sheet
provides basic information on PBDEs to site managers and other field
personnel who may encounter these contaminants at cleanup sites.
PBDEs have been used widely in the United States since the 1970s;
however, there is growing concern about their persistence in the
environment and their tendency to bioaccumulate (ATSDR 2015; EPA
2009).
What are PBDEs?	
~	PBDEs are brominated hydrocarbons in which 2-10 bromine atoms are
attached to the molecular structure (ATSDR 2015).
~	PBDEs are used as flame retardants in a wide variety of products,
including plastics, furniture, upholstery, electrical equipment, electronic
devices, textiles and other household products (ATSDR 2015; EPA
2009).
~	At high temperatures, PBDEs release bromine radicals that reduce
both the rate of combustion and dispersion of fire (Hooper and
McDonald 2000).
~	PBDEs exist as mixtures of distinct chemicals called congeners with
unique molecular structures (ATSDR 2015; EPA 2009).
~	There are three types of commercial PBDE mixtures, including
pentabromodiphenyl ether (pentaBDE), octabromodiphenyl ether
(octaBDE) and decabromodiphenyl ether (decaBDE). DecaBDE is the
most widely used PBDE globally (ATSDR 2015; EPA 2009).
~	The production of octaBDE and pentaBDE in the United States ceased
at the end of 2004 after the voluntary phase-out of these chemicals by
the only U.S. manufacturer. In 2009, the two U.S. producers and the
main U.S. importer of decaBDE announced plans to phase out the
compound by the end of 2013 (EPA 2013).
At a Glance
~	Classes of brominated
hydrocarbons that serve as
flame retardants for electrical
equipment, electronic devices,
furniture, textiles and other
household products.
~	Structurally similar and exhibit
low to moderate volatility. Lower
brominated congeners of PBDE
tend to bioaccumulate more than
higher brominated congeners.
~	Exposure in rats and mice
caused thyroid hormone
bioactivity, neuro-developmental
toxicity and other symptoms.
~	According to EPA, evidence of
carcinogenic potential is
suggested for decaBDE.
~	Detection methods include gas
chromatography, mass
spectrometry and liquid
chromatography.
~	Potential treatment methods
being evaluated at the laboratory
scale include debromination
using zero-valent iron (ZVI) and
nanoscale ZVI, activated carbon
treatment and enhanced
biodegradation.
Disclaimer: The U.S. EPA prepared this fact sheet using the most recent
publicly-available scientific information; additional information can be obtained
from the source documents. This fact sheet is not intended to be used as a
primary source of information and is not intended, nor can it be relied upon, to
create any rights enforceable by any party in litigation with the United States.
Mention of trade names or commercial products does not constitute endorsement
or recommendation for use.
United States	Office of Land and Emergency	EPA 505-F-17-015
Environmental Protection Agency	Management (5106P)	November 2017
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Technical Fact Sheet - PBDEs
~	In 2014, EPA identified 29 potentially functional,	forms of PBDEs that contain higher levels of
viable alternatives to decaBDE for use in select	oxygen (ATSDR 2015).
polyolefins, styrenics, engineering thermoplastics, ~~~ PBDEs are structurally similar to polychlorinated
thermosets, elastomers, or waterborne emulsions	biphenyls (PCBs). PBDEs are fat-soluble and
and coatings (EPA 2014).	hydrophobic (Hooper and McDonald 2000; NTP
~	There are no known natural sources of PBDEs,	2014).
except for a few marine organisms that produce
Exhibit 1: Physical and Chemical Properties of PBDEs
	(ATSDR 2015)	


PBDEs

Property
PentaBDE
OctaBDE
DecaBDE
Chemical Abstracts System (CAS) number
32534-81-9
32536-52-0
1163-19-5
Physical description (physical state at room
temperature)
Clear, amber to pale
yellow liquid
Off-white powder
Off-white powder
Molecular weight (g/mol)
Mixture
Mixture
959.22
Water solubility at 25°C (pg/L)
13.3 (commercial)
Less than 1
(commercial)
Less than 1
Boiling point (°C)
Over 300
Over 330
(decomposes)
Over 320
(decomposes)
Melting point (°C)
-7 to -3 (commercial)
85 to 89 (commercial)
290 to 306
Vapor pressure at 25°C (mm Hg)
2.2 x 10"7 to 5.5 x 10"7
9.0 x 10"10 to 1.7 x 10"9
3.2 x 10"8
Octanol-water partition coefficient (log K0w)
6.64 to 6.97
6.29 (commercial)
6.265
Soil organic carbon-water coefficient (log Koc)
4.89 to 5.10 a
5.92 to 6.22 a
6.80 a
Henry's law constant at 25°C (atm-m3/mol)
1.2 x 10"5a
7.5 x 10"8a
1.62 x 10"6a
Abbreviations: g/moi - gram per mole; |jg/L - micrograms per liter; °C - degrees Celsius; mm Hg - millimeters of mercury; atm-m3/mol -
atmosphere-cubic meters per mole.
a- Estimated value
Existence of PBDEs in the environment
~	PBDEs may enter the environment through
emissions from manufacturing processes,
volatilization from various products that contain
PBDEs, recycling wastes and leachate from waste ,
disposal sites (ATSDR 2015; EU 2001).
~	PBDEs have been detected in air, sediments,
surface water, fish and other marine animals
(ATSDR 2015; EPA 2009).
~	Based on a very limited number of studies,	<
biodegradation does not appear to be significant
for PBDEs (ATSDR 2015).
~	Higher brominated congeners of PBDE tend to	<
bind to sediment or soil particles more than lower
brominated congeners (ATSDR 2015).
~	PBDEs do not dissolve easily in water and bind
strongly to soil or sediment particles. This reduces
their mobility in soil, sediment, surface and
groundwater, but increases their mobility in the
atmosphere, where they are attached to airborne
particulate matter (ATSDR 2015).
Volatilization from soil surfaces is expected to be
low to moderate, depending on the number of
bromine atoms. More brominated congeners
(higher numbers of bromine atoms) tend to exhibit
lower volatilities (EPA 2009; NTP 2014).
Even though PBDEs are stable, they are
susceptible to photolytic debromination when they
are exposed to ultraviolet light (ATSDR 2015).
As of 2016, PBDEs were not identified at any of
the current or former hazardous waste sites on the
EPA National Priorities List (NPL); however, the
number of sites evaluated for PBDEs is not well
documented (EPA 2016).
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Technical Fact Sheet - PBDEs
What are the routes of exposure and the potential health effects of PBDEs?
Routes of potential human exposure to PBDEs are
ingestion, inhalation or dermal contact (NTP
2014).
Traces of PBDEs have been detected in samples
of human tissue, human blood and breast milk
(EPA 2009; He and others 2006)
According to EPA, evidence of carcinogenic
potential is suggested for decaBDE (EPA 2009;
EPA IRIS 2008).
Neither the U.S. Department of Health and Human
Services (DHHS) nor the International Agency for
Research on Cancer (IARC) has classified the
carcinogenicity of any PBDEs (IARC 2016; NTP
2014). However, the National Toxicology Program
(NTP) evaluated a pentabromodiphenyl ether
mixture in a rodent bioassay and concluded there
was clear evidence of carcinogenicity in each
species/sex tested (NTP 2014).
Studies in rats and mice show that PBDEs cause
neurotoxicity, developmental neurotoxicity,
reproductive toxicity, thyroid toxicity,
immunotoxicity, liver toxicity, pancreas effects
(diabetes) and cancer (penta and
decabromodiphenyl ether). There may be
differences in the severity of effects depending on
bromination level (ATSDR 2015; Birnbaum and
Staskal 2004; EPA 2009).
Studies on animals and humans show that some
PBDEs can act as endocrine system disruptors
and tend to deposit in human adipose tissue
(ATSDR 2015; Birnbaum and Staskal 2004; He
and others 2006; NTP 2014).
Studies indicate that octaBDE is a teratogen (a
prenatal developmental toxin) (Darnerud and
others 2001; He and others 2006).
Are there any existing federal and
PBDEs?
~ EPA has established the following chronic oral
reference doses (RfDs) for PBDEs (EPA 2017):
PBDE Congener
Milligrams
per kilogram
per day
(mg/kg/day)
2,2',3,3',4,4',5,5',6,6' decaBDE-209
conqener
7 x 10"3
octaBDE conqener
3 x 10"3
pentaBDE conqener
2 x 10"3
2,2',4,4' - tetrabromodiphenyl ether
(tetraBDE-47) conqener
1 x 10"4
2,2',4,4',5,5' - hexabromodiphenyl
ether (hexaBDE-153) conqener
2 x 10"4
2,2',4,4',5 - pentaBDE-99 conqener
1 x 10"4
~	For decaBDE-209, EPA has assigned an oral slope
factor for carcinogenic risk of 7 x 10 4 (mg/kg/day)1
and a drinking water unit risk of 2.0 x 10~8 micrograms
per liter (jjg/L) (EPA IRIS 2008).
~	EPA risk assessments indicate that the drinking
water concentration representing a 1 x 10 6 cancer
risk level for decaBDE-209 is 50 |jg/L (EPA IRIS
2008).
guidelines and health standards for
~ EPA has calculated the following screening levels for
residential soil, industrial soil and tap water (EPA
2017):
Chemical
Residential
Industrial
WSSM

Soil
Soil


(mg/kg)
(mg/kg)

decaBDE-
440
3,300
110
209



octaBDE
190
2,500
61
pentaBDE
160
2,300
40
tetraBDE-47
6.3
82
2.0
hexaBDE-
13
160
4.0
153



pentaBDE-99
6.3
82
2.0
~	For lower brominated PBDEs, the Agency for Toxic
Substances and Disease Registry (ATSDR) has
established a minimal risk level (MRL) of 0.006
milligrams per cubic meter for intermediate-
duration inhalation exposure. In addition, ATSDR
established an MRL of 6 x 10 5 mg/kg/day for
acute-duration oral exposure and 3x10 ®
mg/kg/day for intermediate-duration oral exposure
(ATSDR 2016).
~	Some states, including California, Hawaii, Illinois,
Maine, Maryland, Michigan, Minnesota, New York,
Oregon, Rhode Island and Washington, have
banned pentaBDE and octaBDE. States such as
Maine, Maryland, Oregon and Washington have
also introduced legislation that bans the sale of
certain products containing decaBDE (EPA 2009).
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Technical Fact Sheet - PBDEs
~ EPA issued a Significant New Use Rule (SNUR) in
2006 to phase out pentaBDE and octaBDE.
According to this rule, no new manufacture or
import of these two congeners is allowed after
January 1, 2005, without a 90-day notification to
EPA for evaluation (EPA 2013).
~ In December 2009, the two U.S. producers and the
main U.S. importer of decaBDE committed to end
production, import and sales of the chemical for all
consumer, transportation and military uses by the
end of 2013 (EPA 2014). However, based on 2012
industry comments to EPA, there may be ongoing
uses for decaBDE.
What detection and site characterization methods are available
for PBDEs?
~ Analytical methods used for PBDE detection
include gas chromatography (GC)-mass
spectrometry (MS) for air, sewage, fish and animal
tissues; capillary column GC/electron capture
detector (ECD) for water and sediment samples;
GC/high resolution MS (HRMS) for fish tissue; and
liquid chromatography (LC)-GC-MS/flame
ionization detector (FID) for sediments (ATSDR
2015).
~ EPA Method 1614 uses isotope dilution and
internal standard high resolution GC
(HRGC)/HRMS to detect PBDEs in water, soil,
sediment and tissue (EPA 2007).
What technologies are being used to treat PBDEs?
Research is being conducted at the laboratory
scale on potential treatment methods for media
contaminated with PBDEs.
Anaerobic bacteria may be utilized to partially
degrade higher brominated PBDE, but may lead to
the formation of less-brominated, more toxic
congeners (He and others 2006; Lee and He
2010).
Secondary treatment using cationic surfactants
may be required to increase the availability of
PBDE molecules for reactions with zero valent iron
(ZVI) (Keum and Li 2005).
Laboratory studies are also evaluating the use of
bimetallic nanoparticles (BNPs) and nanoscale
ZVI (nZVI) for the treatment of PBDEs. Sequential
treatment with nZVI and aerobic biodegradation
and treatment with iron silver BNPs coupled with
microwave energy were both shown to effectively
degrade PBDEs (Kim and others 2012, 2014; Luo
and others 2012).
A 2016 laboratory study indicates a tourmaline
catalyzed Fenton-like reaction can remove PBDEs
from soil (Li and others 2016).
Bench-scale experiments indicate that
electrokinetic remediation may be effective for the
treatment of PBDEs in soil (Chun and others
2012).
The use of activated carbon has also been
investigated in a laboratory study for the treatment
of PBDE in sediment (Choi and others 2003).
Where can I find more information about PBDEs?
ATSDR. 2015. "Draft Toxicological Profile for
Polybrominated Diphenyl Ethers."
www.atsdr.cdc.gov/toxprofiles/tp207.pdf
ATSDR. 2016. "Minimal Risk Levels (MRLs)."
www.atsdr.cdc.gov/mrls/index.html
Birnbaum, L.S., and D.F. Staskal. 2004.
"Brominated Flame Retardants: Cause for
Concern?" Environmental Health Perspectives.
Volume 112 (1). Pages 9 to 13.
Choi, J., Onodera, J., Kitamura, K., Hashimoto, S.,
Ito, H., Suzuki, N., Sakai, S., and M. Morita. 2003.
"Modified Clean-up for PBDD, PBDF and PBDE
with an Active Carbon Column—Its Application to
Sediments." Chemosphere. Volume 53 (6). Pages
637 to 643.
Chun, D.W., Cui, P.F., and J.E. Qing. 2012. "Study
on Electrokinetic Remediation of PBDEs
Contaminated Soil." Advanced Materials Research.
Volumes 518 to 523. Pages 2829 to 2833.
Darnerud, P.O., Eriksen, G.S., Johannesson, T.,
Larsen, P.B., and M. Viluksela. 2001.
"Polybrominated Diphenyl Ethers: Occurrence,
Dietary Exposure, and Toxicology." Environmental
Health Perspectives. Volume 109 (1). Pages 49 to
68.
European Union (EU). 2001. "Diphenyl ether,
pentabromo derivative (pentabromodiphenyl
ether)." European Union Risk Assessment Report.
Luxembourg: Office for Official Publications of the
European Committees
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Technical Fact Sheet - PBDEs
Where can I find more information about PBDEs? (continued)
He, J., Robrock, K.R., and L. Alvarez-Cohen. 2006.
"Microbial Reductive Debromination of PBDEs."
Environmental Science & Technology. Volume 40
(14). Pages 4429 to 4434.
Hooper, K., and T.A. McDonald. 2000. "The
PBDEs: An Emerging Environmental Challenge
and Another Reason for Breast-Milk Monitoring
Programs." Environmental Health Perspectives.
Volume 108 (5). Pages 387 to 392.
International Agency for Research on Cancer
(IARC). 2016. "Agents Classified by the IARC
Monographs, Volumes 1-107."
monoqraphs.iarc.fr/ENG/Classification/index.php
Keum, Y-S., and Q.X. Li. 2005. "Reductive
Debromination of PBDEs by Zero-Valent Iron."
Environmental Science & Technology. Volume 39.
Pages 2280 to 2286.
Kim, E., Kim, J., Kim, J., Bokare, V., and Y. Chang.
2014. "Predicting Reductive Debromination of
Polybrominated Diphenyl Ethers by Nanoscale
Zero Valent Iron and Its Implications for
Environmental Risk Assessment." Science of the
Total Environment. Volumes 470 to 471. Pages
1553 to 1557.
Kim, Y., Murugesan, K., Chang, Y., Kim, E., and Y.
Chang. 2012. "Degradation of Polybrominated
Diphenyl Ethers by a Sequential Treatment with
Nanoscale Zero Valent Iron and Aerobic
Biodegradation." Journal of Chemical Technology
and Biotechnology. Volume 87 (2). Pages 216 to
224.
Lee, L.K., and J. He. 2010. "Reductive
Debromination of Polybrominated Diphenyl Ethers
by Anaerobic Bacteria from Soils and Sediments."
Applied and Environmental Microbiology. Volume
76. Pages 794 to 802.
Li, J., Wang, C., Wand, D., Zhou, Z., Sun, H., and
S. Zhai. 2016. "A Novel Technology for
Remediation of PBDEs Contaminated Soils Using
Tourmaline-catalyzed Fenton-like Oxidation
Combined with P. chrysosporium." Chemical
Engineering Journal. Volume 296. Pages 319 to
328.
~	Luo, S., Yang, S., Sun, C., and J. Gu. 2012.
"Improved Debromination of Polybrominated
Diphenyl Ethers by Bimetallic Iron-Silver
Nanoparticles Coupled with Microwave Energy."
Science of the Total Environment. Volume 429.
Pages 300 to 308.
~	National Toxicology Program. 2014. "Report on
Carcinogens, Fourteenth Edition." Research
Triangle Park, NC: U.S. Department of Health and
Human Services, Public Health Service.
ntp.niehs.nih.aov/pubhealth/roc/index-1 .html
~	U.S. Environmental Protection Agency (EPA).
2007.	"Method 1614 Brominated Diphenyl Ethers
in Water, Soil, Sediment and Tissue by
HRGC/HRMS." EPA 821-R-07-005.
www.epa.gov/sites/production/files/2015-
08/documents/method 1614a 2010.pdf
~	EPA. 2009. "Polybrominated Diphenyl Ethers
(PBDEs) Action Plan Summary." www.epa.gov/
assessinq-and-managing-chemicals-under-tsca/
polvbrominated-diphenvl-ethers-pbdes-action-plan
~	EPA. 2013. "Polybrominated Diphenyl Ethers
(PBDEs) Significant New Use Rules (SNUR)."
www.epa.gov/assessing-and-managing-chemicals-
under-tsca/polvbrominated-diphenvlethers-pbdes-
siqnificant-new-use
~	EPA. 2014. "An Alternatives Assessment for the
Flame Retardant decabromodiphenyl ether
(decabde)." www.epa.gov/sites/production/
files/2014-05/documents/decabde final.pdf
~	EPA. 2016. Superfund Information Systems.
Superfund Site Information, cumulis.epa.
g o v/s u pe rcpad/cu rs ites/s rchs ites. cf m
~	EPA. 2017. Regional Screening Level (RSL)
Summary Table, www.epa.gov/risk/regional-
screening-levels-rsls-generic-tables-mav-2016
~	EPA Integrated Risk Information System (IRIS).
2008.	"2,2',3,3',4,4',5,5',6,6' -Decabromodiphenyl
ether (BDE-209) (CASRN 1163-19-5)."
www.epa.gov/iris
Contact Information
If you have any questions or comments on this fact sheet, please contact: Mary Cooke, FFRRO, at
cooke.marvt@epa.gov.
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