U.S. Environmental Protection Agency

8/18/2010

Hexabromocvclododecane (HBCD)

Action Plan

I.	Overview

HBCD is a brominated flame retardant found world-wide in the environment and
wildlife. Human exposure is evidenced from its presence in breast milk, adipose tissue and
blood. It bioaccumulates and biomagnifies in the food chain. It persists and is transported long
distances in the environment, and highly toxic to aquatic organisms. It also presents potential
human health concerns based on animal test results indicating potential reproductive,
developmental and neurological effects. For these reasons, the Environmental Protection
Agency (EPA) intends to consider initiating action under the Toxic Substances Control Act to
address the manufacturing, processing, distribution in commerce, and use of HBCD.

As part of the Agency's efforts to address HBCD, EPA also intends to evaluate the
potential for disproportionate impact on children and other sub-populations.

II.	Introduction

As part of EPA's efforts to enhance the existing chemicals program under the Toxic
Substances Control Act (TSCA)1, the Agency has identified certain widely recognized
chemicals, including HBCD, for action plan development based on their presence in humans;
persistent, bioaccumulative, and toxic (PBT)2 characteristics; use in consumer products;
production volume; or other similar factors. This Action Plan is based on EPA's initial review of
readily available use, exposure, and hazard information on HBCD. EPA considered which of the
various authorities provided under TSCA and other statutes might be appropriate to address
potential concerns with HBCD in developing the Action Plan. The Action Plan is intended to
describe the courses of action the Agency plans to pursue in the near term to address its
concerns. The Action Plan does not constitute a final Agency determination or other final
Agency action. Regulatory proceedings indicated by the Action Plan will include appropriate
opportunities for public and stakeholder input, including through notice and comment
rulemaking processes.

III.	Scope of Review

HBCD is a category of brominated flame retardants, consisting of 16 possible isomers. It
has a molecular formula of Ci2Hi8Br6 and its structure consists of a ring of 12 carbon atoms to
which 18 hydrogen and six bromine atoms are bound. Hexabromocyclododecane may be
designated as a non-specific mixture of all isomers (Hexabromocyclododecane; CASRN 25637-
99-4) or as a mixture of three main diastereomers (1,2,5,6,9,10-hexabromocyclododecane;
CASRN 3194-55-6. Both CASRNs are listed on the TSCA Inventory. Commercial preparations
of HBCD may contain some possible impurities, such as tetrabromocyclododecene or other.

1	15 U.S.C. §2601 etseq.

2	Information on PBT chemicals can be found on the EPA website at:
http://www.epa.gov/oppt/newchems/pubs/pbtpolcY.htm


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isomeric HBCDs (UNEP, 2009). All isomers of HBCD are the subject of this Action Plan,
irrespective of the particular CASRN or name used to identify them3.

IV. Uses and Substitutes Summary

Uses

HBCD, with an 8% share in the brominated flame retardant (BFR) global market in 2001,
is the third most commonly used BFR, following tetrabromobisphenol A (TBBPA;
approximately 59% of the market), and decabromodiphenyl ether (deca-BDE; 26% market share)
(Morose, 2006).

The main use of HBCD is as a flame retardant in expanded polystyrene foam (EPS) and
extruded polystyrene foam (XPS) (Weil and Levchik, 2009). EPS and XPS are used primarily
for thermal insulation boards in the building and construction industry (Morose, 2006). HBCD is
used because it is highly effective at low concentrations; EPS boards contain approximately
0.5% HBCD by weight in the final product (Morose, 2006).

HBCD may also be used as a flame retardant in the backcoating of textiles for
upholstered furniture, upholstery seating in transportation vehicles, draperies, wall coverings,
mattress ticking, and interior textiles such as roller blinds (Morose, 2006; ECHA, 2009). The
maximum concentration of CASRN 3194-55-6 for use in fabrics and textiles and in rubber and
plastic products ranges from 1-30% (US EPA, 2006). The majority of HBCD used in textiles is
for upholstered furniture, in order to meet the stringent fire safety laws of the United Kingdom
and California (Morose, 2006). However, according to the 2006 TSCA Inventory Update Rule
(IUR) data (which includes information for chemicals manufactured and imported in amounts of
25,000 pounds or greater at a single site), less than 1% of the total commercial and consumer use
of HBCD was used for fabrics, textiles and apparel (US EPA, 2006).

In addition, HBCD is used as a flame retardant in high impact polystyrene (HIPS) for
electrical and electronic appliances such as audio-visual equipment, and some wire and cable
applications (Morose, 2006 and ECHA, 2009). Less than 10% of all HBCD used in Europe is
used in HIPS (ECHA, 2009).

Production

The annual United States (U.S.) import/production volume of CASRN 25637-99-4 was
between 10,000 and 500,000 pounds as reported to EPA in 2002; no import/production was
reported in 2006 (US EPA, 2006). The annual U.S. import/production volume of CASRN 3194-
55-6 was 10-50 million pounds reported in 2002 and 2006 (US EPA, 2006). The U.S.
International Trade Commission reported that 380,000 pounds of HBCD (1,3,5,7,9,11-HBCD
isomer) were imported in 2008 (US ITC, 2010). In 2006, five facilities reported either the
manufacture or importation of at least 25,000 pounds of HBCD: Albemarle (2 facilities), BASF,
LG Chem America and Chemtura (US EPA, 2006).

3 For example, The U.S. International Trade Commission December 2009 Publication 4121 reports importation of
the 1,3,5,7,9,11-HBCD isomer which would be subject to this action plan.

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Substitutes

According to the European Chemicals Agency (ECHA) there are currently no
commercially or technically viable alternatives for HBCD as a flame retardant in polystyrene
foam, as all alternative flame retardants it noted impair the structure and properties of the foam,
making it unsuitable for use (ECHA, 2009). Some commercially available brominated flame
retardants may be used in EPS foam (e.g., tetrabromo-cyclooctane, dibromoethyldibromo-
cyclohexane and TBBPA), but a detailed analysis of their effectiveness in this application when
compared with HBCD is not available (Morose, 2006). There are commercially available
substitutes for XPS and EPS foam board in the construction process that do not use brominated
flame retardants. Polyester and polyether polyols, as well as phenolic foam may be used to
produce insulation boardstock from rigid foam. Other substitutes include alternative insulation
types such as blanket, loose-fill, and reflective insulation (Morose, 2006).

Several chemicals may be used as alternatives for HBCD in textile applications. For
textile backing, these include deca-BDE, chloroparaffins and ammonium polyphosphate (ECHA,
2009). There are several alternatives to HBCD for use in high-impact polystyrene (HIPS).
Deca-BDE is currently the most widely used flame retardant in HIPS (Weil and Levchik, 2009)
and is also used in electronic wire insulation. Deca-BDE and chloroparaffins may not be suitable
for use as substitutes for HBCD due to concerns about their persistent, bioaccumulative and toxic
properties. Other chemicals that can be used as alternatives to HBCD in HIPS include both
halogenated flame retardants used in conjunction with antimony trioxide (ATO) and organic aryl
phosphorus compounds (ECHA, 2009).

V. Hazard Identification Summary

Human Health Effects

HBCD is absorbed via the gastro-intestinal tract and accumulates in the adipose tissue
(body fat), muscle and liver in experimental animals (Chengelis, 2001). Bioaccumulation was
observed to be higher in female than male rats (Chengelis, 2001). The elimination of HBCD
from body fat is markedly slower than from other tissues with an elimination half-life of weeks
to months (Chengelis, 2001). Repeated exposure of HBCD to rats showed disturbances in
thyroid hormone system and effects on the thyroid in males and females (Chengelis, 2001). A
study by Eriksson, et al. (2006), concluded that neonatal exposure of HBCD to mice affected
spontaneous motor behavior, learning and memory processes in adult mice. However, this study
was not conducted according to established OECD4 test guidelines. In a recently conducted,
more robust, two-generation reproductive toxicity study in rats conducted according to
established test guidelines, HBCD showed treatment-related reproductive effect (a significant
decrease in the number of primordial follicles in the F1 females) (Ema, et al., 2008). Although
this decrease in ovarian follicles did not affect any reproductive parameters in this study, this
effect is suggestive of potential reproductive toxicity. Developmental effects were observed
including delays in eye opening in the second (F2) generation and transient changes in learning

4 Organization for Economic Cooperation and Development

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and memory in F1 males, but exposure did not cause any changes in spontaneous behavior. In
addition, there was high and dose-dependent pup mortality during lactation (Ema, et al., 2008).

Environmental Effects

Laboratory studies have shown that HBCD is capable of producing adverse effects in a
variety of organisms including algae, fish, invertebrates and soil-dwelling organisms at
environmentally relevant concentrations. HBCD is toxic to algae and acutely toxic to fish
embryos (Desjardins, et al., 2004; Deng, et al., 2009). A number of sub-lethal effects (e.g.,
altered thyroid status, protein metabolism, oxidative stress, reproductive activity) have also been
observed in fish (Palace, et al., 2008; Kling and Forlin, 2009; Zhang, et al., 2008; Ronisz, et al.,
2004). Drottar and Krueger (1998) reported a reduced number and size of daphnid offspring in
first and second generations. Thyroid hormone-dependent developmental effects were observed
in tadpoles (Xenopus laevis) exposed to HBCD (Schriks, et al., 2006). HBCD has been reported
to reduce egg production and lower biomass in soil dwelling organisms (Lumbriculus variegatus)
(Oetken, et al., 2001). HBCD administered to chicken (Gallus domesticus) embryonic
hepatocytes in vitro resulted in significant alterations in expression of genes (mRNA) associated
with liver and thyroid function (Crump, et al., 2008). Thinner egg shells were measured in
American kestrels exposed to a combination of PBDEs and HBCD (Fernie, et al., 2009).

VI. Physical-Chemical Properties and Fate Characterization Summary

The members of the HBCD flame retardants category are solids with negligible to low
vapor pressure and negligible to low water solubility. [Molecular Weight = 642; Melting Point =
190 °C (average); Vapor Pressure 6.3 x 10"5 Pa at 21°C; log Kow = 5.6 (technical product); and
Water Solubility 66 ppb ((J-g/L) (EC 2008).

Persistence

Limited data are available on the degradation of HBCD in soil, water or sediment.
Laboratory studies have shown that HBCD is degraded by abiotic and biotic processes in soil
and aquatic sediment with reported half-lives of 2 days to 2 months (Davis, et al., 2005; 2006).
These data are consistent with low persistence according to half-life criteria set forth in the PMN
program (64 FR 60194, November 4, 1999) and international Persistent Organic Pollutants
(POPs) protocols (UNEP, 2007; Norden, 2008). However, environmental monitoring data shows
frequent occurrence of HBCD in biota over large areas and in remote locations where no
demonstrable sources have been shown to account for the exposures (see discussion of
environmental exposures in Section VII below), supporting the finding that HBCD is sufficiently
persistent in the environment to be of concern within the scope of these international protocols.
Measured levels of HBCD in dated sediment core samples also provide evidence of persistence
(UNEP, 2007). The frequent detection of HBCD over a large geographic area, with increasing
exposure in remote locations such as the Arctic, where no demonstrable local sources exist that
can account for these exposures, suggest that HBCD is persistent and undergoes long-range
atmospheric transport (UNEP, 2007).

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Bioaccumulation

HBCD is highly bioaccumulative. Veith, et al. (1979) reported a measured
bioconcentration factor (BCF) of 18,100 for HBCD in fathead minnows, and this value was later
confirmed by a kinetic study with rainbow trout (Drottar, et al., 2001), for which the mean BCF
was 19,200. A monitoring study by deBoer, et al. (2002) included a wide variety of biota
(invertebrates, fish, birds and marine mammals) and showed that HBCD bioaccumulates easily
and biomagnifies in food chains. In a Swedish monitoring study (Sellstrom, et al. 1998), a fish-
to-sediment ratio of 15 to 1 (expressed as a biota/sediment accumulation factor or BSAF of 15)
was reported for one of two sites, indicating that HBCD is bioavailable and bioaccumulative.
Isomer-specific biomagnification has been demonstrated based on monitoring of a Lake Ontario
food web (Tomy, et al. 2004). Monitoring in Sweden found much higher levels of HBCD in
eggs from wild peregrine falcons than from captive populations feeding on chickens (Lindberg,
et al., 2004) or guillemot from the Baltic Sea (Sellstrom, et al., 2003), demonstrating that HBCD
may also bioaccumulate in terrestrial organisms and food chains.

VII. Exposure Characterization Summary

Releases

HBCD is not reported in the Toxics Release Inventory. No readily available quantitative
release information in the U.S. was found. ECHA reported a total of about 3,100 kg/year of
HBCD released to the environment in Europe in 2008, of which 50% were to wastewater, 29% to
surface water and 21% to air (ECHA, 2009). The overall volume used in 2007 was estimated at
11.6 million kg/year (ECHA, 2009). A Swedish article indicates the primary source of release of
HBCD in Europe is from textile applications (KEMI, 2006). Based on IUR data, the volume of
HBCD used for textile application in the U.S. is estimated to be < 1 % of the total volume of
HBCD produced/imported and hence releases from this use in the U.S. are expected to be
relatively small (as a percentage of overall volume produced/imported).

Information from the United Kingdom indicates that the primary sources of HBCD in the
environment are from fugitive emissions during its manufacture and use in subsequent products,
potentially from leaching in landfills, and from incinerator emissions (UKEA, 2009). As an
additive flame retardant, HBCD is not chemically bound to the matrix of the material it protects,
and thus has the potential to enter the environment from the finished products in use or after
disposal (US EPA, 2008b). ECHA states: "A substantial proportion of articles containing
HBCD will have very long service life (30+ years for typical insulation like EPS and XPS) and
environmental releases will continue for a long time into the future." (ECHA, 2009). It is not
known how comparable the releases of HBCD from manufacturing and use operations in the
U.S. are to those reported in Europe.

Human Exposure

HBCD is typically manufactured as a powder of approximately 100 microns in size;
however, a portion of the materials is micronized to 1 micron during manufacture (U.S. Patent
4980382), which poses the potential of deep lung particulate exposure (Rozman, et al., 2001)).

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Workers who do not wear appropriate respiratory protection have the high potential for deep
lung exposure of the 1 micron material. Particles 1 micron and smaller are able to penetrate to
the alveolar sacs of the lungs. They may be absorbed into blood or cleared through the
lymphatics. The overall removal of particles from the alveoli is relatively inefficient; on the first
day only about 20 percent of particles are cleared, and the portion remaining longer than 24
hours is cleared very slowly. Some particles may remain in the alveoli indefinitely (Rozman, et
al., 2001). Commercial workers also may have potential dermal and inhalation exposure to the
chemical during application (EC, 2008). The Occupational Safety and Health Administration
(OSHA) has not established a Permissible Exposure Limit for HBCD. An occupational exposure
study at an industrial plant in Europe producing EPS, reported measured elevated airborne dust
levels and measured HBCD in the blood of workers (Thomsen, et al., 2007). No readily
available HBCD occupational exposure information (including biomonitoring data) was found
for U.S. workers. Based on available IUR reporting, the maximum total number of industrial
workers likely to be exposed to this chemical during manufacturing and industrial processing and
use is between 100 and 999 (US EPA, 2006); however, this is likely an underestimate since it
does not include the commercial workers and some IUR submitters did not have to report
numbers of workers because they manufacture below the threshold required for reporting or the
information was reported to be not readily obtainable.

HBCD has been detected in human adipose tissue, milk, and blood (Covaci, et al, 2006;
Johnson-Restrepo, et al, 2008; Arnot, et al., 2009). General population exposure to HBCD is
likely from its presence in food (Hiebl and Vetter, 2007; Fernandes, et al., 2008; van Leeuwen
and de Boer, 2008), outdoor air, particularly near point sources (Covaci, et al., 2006), and indoor
air (Law, et al., 2008). HBCD has also been detected in indoor dust (Covaci, et al., 2006; Law,
et al., 2008; Roosens, et al., 2009).

The IUR information suggests either that HBCD will not be used in children's consumer
products or that this type of information is not readily available. However, to the extent it is
present in household applications (e.g., building foam, furniture upholstery, carpeting), children
could be exposed, especially given children's increased exposure via dust and the hand-to-mouth
ingestion pathway. In vitro experiments conducted to demonstrate leaching of HBCD from
textiles showed that the presence of simulated biological fluids (sweat, saliva) and fruit juices
enhances the leaching of HBCD from back-coated samples (Ghanem, 2009). Children's
exposure to HBCD from mouthing of textiles and from ingestion of dust has been estimated (EC,
2008).

Environmental Exposure

HBCD has been measured in air and sediment in Scandinavian countries, North America
and Asia (Covaci, et al., 2006, Arnot, et al., 2009). HBCD has been measured in marine and
arctic mammals, freshwater and marine fish, aquatic invertebrates, birds and bird eggs, and one
plant species (Covaci, et al., 2006; Arnot, et al., 2009). HBCD has been detected in Arctic air in
northern Scandinavia and in Arctic birds and bird eggs, Arctic fish, ringed seals and polar bears
(UNEP, 2009). It has been detected in freshwater, marine, and avian organisms, and in upper
trophic-level mammals (polar bears and seals). The majority of these studies are European, some

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are from North America, and a few are from Asia. A study reported decreased levels of HBCD
in biota once a United Kingdom manufacturing plant was closed (Law, et al., 2008b).

VIII. Risk Management Considerations

HBCD is of international concern because of its PBT properties. HBCD was added to
ECHA's list of Substances of Very High Concern (SVHCs) on October 28, 2008 (ECHA, 2008).
HBCD is under consideration for listing under the POPs Protocol to the Convention on Long-
Range Transboundary Air Pollution, as technical review has concluded that HBCD is persistent,
bioaccumulative, can cause adverse effects to humans or the environment, and has the potential
to be transported long distances within the meaning of the Protocol (UNECE, 2010). Under the
Stockholm Convention for Persistent Organic Pollutants, the POPs Review Committee decided
in October 2009 that Annex D screening criteria have been met for HBCD; further
determinations have not been made (UNEP, 2010).

HBCD is persistent, bioaccumulative and toxic, especially to aquatic organisms. HBCD
biomagnifies in food chains. Given its presence in the environment including wildlife, and the
high hazard for HBCD to algae and aquatic invertebrates, EPA has a concern for the potential
risk to these aquatic organisms.

EPA has presented evidence which strongly suggests there is potential for exposure to the
general population from HBCD in the environment, as well as exposure to HBCD from products
and dust in the home and workplace. HBCD shows toxicity in repeated-dose (28- and 90-day
feeding studies) tests. There may be some human health hazard concern based on thyroid effects
and indications of developmental and transient neurobehavioral effects. These health effects
combined with potential exposures suggests some concern for a potential risk to the general
population from HBCD is warranted. Greater concern is warranted for workers who
manufacture the chemical and produce products that contain it, given available expose
information.

Availability of substitutes for HBCD uses is an unresolved issue, especially for EPS and
XPS building foam board applications, where other, more suitable flame retardants may not be
readily available.

HBCD is currently on the Integrated Risk Information System (IRIS) program agenda.
The anticipated date for a completed assessment has not yet been determined. (US EPA, 2010).
HBCD is under consideration for inclusion in the NHANES human bio-monitoring program,
which could provide data on exposure in the U.S.

Potential Impacts on Children

HBCD is found in household dust, and it is used in the U.S. in certain consumer products,
both of which could represent exposure pathways to children. HBCD has been measured in
blood serum and breast milk, so that a developing fetus or nursing infant could be exposed to it.
The reproductive, developmental and neurotoxic health hazards that could result from exposures
to HBCD are an important consideration in protecting children's health. These factors suggest

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that concerns for potential risks to children and pregnant women should be considered with any
actions taken to manage this chemical.

IX. Next Steps

In conducting this review of HBCD, EPA considered a number of potential risk
management actions, including regulatory actions under TSCA sections 4 and 5 and under the
Emergency Planning and Community Right-to-Know Act (EPCRA) 313, as well as voluntary
actions through such programs as Design for the Environment (DfE).

Based on its screening-level review of hazard and exposure information, EPA intends to
initiate actions to protect humans and the environment from exposure to HBCD due to
manufacture (including import) use, or disposal of commercial HBCD. In addition, as part of the
Agency's efforts to address these chemical substances, EPA also intends to evaluate the potential
for disproportionate impact of exposure to HBCD on children and other sub-populations.

On the basis of existing information, the Agency believes that the following actions
would be warranted:

•	Consider initiating rulemaking under TSCA Section 5(b)(4) of TSCA to add HBCD to
the list of chemicals which present or may present an unreasonable risk of injury to health
or the environment. EPA intends to publish a notice of proposed rulemaking by the end
of 2011.

•	Initiating rulemaking under TSCA section 5(a)(2) to designate manufacture or processing
of HBCD for use in consumer textiles as a flame retardant as a significant new use which
would require manufacturers and processors to notify EPA before manufacturing or
processing HBCD for the significant new use. This Significant New Use Rule (SNUR)
also would be proposed to apply to imports of consumer textiles articles containing
HBCD. EPA has evidence to suggest that the use of HBCD in textiles may be limited to
specialty commercial applications, and that general consumer textile use may be so
limited it would be appropriate for SNUR regulation. If information shows this
assumption to be incorrect, EPA will consider initiating rulemaking under TSCA section
6(a) to address general consumer textile use.

•	Consider initiating rulemaking under TSCA section 6(a) to regulate HBCD. A section
6(a) action could take the form of a comprehensive ban on the manufacturing, processing,
distribution in commerce and use of a chemical substance, or a more targeted regulation
to address specific activities. The extent of the rule for HBCD would be determined
during the rulemaking process.

•	Initiating rulemaking in late 2011 to add HBCD to the Toxics Release Inventory. HBCD
is currently not listed by any CASRN on the Emergency Planning and Community Right-
to-Know (EPCRA) section 313 list of toxic substances. Listing will require
manufacturers or importers to provide environmental release information not currently
captured by IUR.

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• Conduct a Design for the Environment and Green Chemistry alternatives assessment of
HBCD. The information developed could be used to encourage industry to move away
from HBCD instead of, in addition to, or as part of any regulatory action taken under
TSCA. The alternatives assessment would build upon existing knowledge and would
consider various exposed populations, including sensitive human subpopulations, as well
as environmental exposure. The work will begin in 2011, with completion expected in
2013.

X. References

Arnot, J., McCarty, L., Armitage, J., Toose-Reid, L., Wania, F., and Cousins, I. 2009. An evaluation of
hexabromocyclododecane (HBCD) for Persistent Organic Pollutant (POP) properties and the potential for adverse
effects in the environment. Submitted to European Brominated Flame Retardant Industry Panel (EBFRIP). 26 May
2009.

Chengelis, C. 2001. An oral (gavage) 90 day toxicity study of HBCD in rats. Study No. WIL-186012. WIL Research
Laboratories, Inc., Ashland, Ohio.

Covaci, A., Gerecke, A.C., Law, R.J., Voorspoels, S., Kohler, M., Heeb, N.V., Leslie, H., Allchin, C.R., and De
Boer, J. 2006. Hexabromocyclododecanes (HBCDs) in the Environment and Humans: A Review. Environ. Sci.
Technol. 40, 3679-3688.

Crump, D. ; Chiu, S.; Egloff, C. ; Kennedy. S.W. 2008. Effects of hexabromocyclododecane and polybrominated
diphenyl ethers on mRNA expression in chicken (Gallus domesticus) hepatocytes. Toxicol. Sci. 2008, 106, 479-487.

Davis JW, S Gonsior, G Marty, J Ariano. 2005. The transformation of hexabromocyclododecane in aerobic and
anaerobic soils and aquatic sediments. Water Res. 39:1075-1084.

Davis JW, SJ Gonsior, DA Markham, URS Friederich, RW Hunziker, JM Ariano. 2006. Biodegradation and product
identification of [14C]hexabromocyclododecane in wastewater sludge and freshwater sediment. Environ. Sci.
Technol. 40:5395-5401.

DeBoer J.; Allchin, C.; Zegers, B.; Boon, J.P.; Brandsma, S.A.; Morris, S.; Kruijt, A.W.; van der Veen, I.;
Hesselingen, J.M.; Haftka, J.J.H.. 2002. HBCD and TBBP-A in sewage sludge, sediments and biota, including
interlaboratory study. Ymuiden, The Netherlands: Netherlands Institute for Fisheries Research (RIVO) BV. Report
number C033/02.

Deng, J.; Yu, L,; Liu, C. ; Yu , K. ; Shi,, X.; Yeung, L.W.Y. ; Lam, P.K.S. ; Wu, R.S.S. ;Zhou B. 2009.
Hexabromcyclododecane-induced developmental toxicity and apoptosis in zebrafish embryos. Aquatic Toxicol.
2009, 93, 29-36.

Desjardins D.; MacGregor, J.A.; Krueger, H.O. 2004. Hexabromocyclododecane (HBCD): A 72-hour toxicity test
with the marine diatom (Skeletonema costatum). Final Report. Wildlife International, Ltd., Easton, Maryland, USA.
pp 66.

Drottar KR and Krueger HO. 1998. Hexabromocyclododecane (HBCD): An flow-through life-cycle toxicity test
with the cladoceran (Daphnia magna). Final report. 439A-108, Wildlife International, Ltd, Easton, Maryland, USA.
1998. 78pp.

Drottar, K.R.; MacGregor, J.A.; Krueger, H.O. 2001. Hexabromocyclododecane (HBCD): An early life-stage

toxicity test with the rainbow trout (Oncorhynchus mykiss). Final

Report. Wildlife International, Ltd, Easton, Maryland, USA. 2001. pp 1-102.

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EC 2000. European Commission 2000 IUCLID Dataset for Hexabromocyclododecane [25637-99-4]

EC 2008. European Commission. Risk Assessment: Hexabromocyclododecane CAS-No.: 25637-99-4 EINECS-
No.: 247-148-4, Final Report May 2008. Office for Official Publications of the European Communities:
Luxembourg, 2008.

ECHA2008. European Chemicals Agency. Decision Number ED/67/2008. October 28, 2008.

ECHA, 2009. European Chemicals Agency. Data on Manufacture, Import, Export Uses and Releases of HBCDD as
well as Information on Potential Alternatives to Its Use. December 1, 2009.
http://echa.europa.eu/doc/consultations/recommendations/tech_reports/tech_rep_hbcdd.pdf

Ema, M., Fujii, S., Hirata-Koizumi, M., and Matsumoto, K. 2008. Two-generation reproductive toxicity study of the
flame retardant hexabromcyclododecane in rats. Reproductive Toxicology, 25:335-351.

Eriksson, P.; Fisher, C.; Wallin, M.; Jakobsson, E.; Fredriksson, A. 2006. Impaired behaviour,

learning and memory, in adult mice neonatally exposed to hexabromocyclododecane (HBCDD). Environ. Toxicol.

Pharmacol. 2006,21,317-322.

Fernandes, A., Dicks, P., Mortimer, D., Gem, M., Smith, F., Driffield, M., White, S., and Rose, M. 2008.

Brominated and chlorinated dioxins, PCBs, and brominated flame retardants in Scottish shellfish: methodology,
occurrence and human dietary exposure. Mol. Nutr. Food Res. 52, 238-249.

Fernie, K.J. ; Shutt, J.L. ; Letcher, R.J. ; Ritchie, I.J. ; Bird, D.M. 2009. Environmentally relevant concentrations of
DE-71 and HBCD alter eggshell thickness and reproductive success of American kestrels. Environ. Sci. Technol.
2009, 43, 2124-30.

Ghanem, R. 2009. Kinetics of Thermal and Photolytic Segregation of Hexabromocyclododecane in Backcoated
Textile Samples. Jordan J Chem. 4, 171-181.

Guerra, P.,et al.; (2009); Transfer of hexabromocyclododecane from industrial effluents to sediments and biota:

Case study in Cinca river (Spain). Journal of Hydrology, 2009, 378, 355.

Heibl, J., and Vetter W. 2007. Detection of hexabromocyclododecane and its metabolite pentabromocyclodedecane
in chicken egg and fish from the official food control. J. Agric. Food Chem. 55, 3319-3324.

Johnson-Restrepo, B., Adams, D.H., and Kannan, K. 2008. Tetrabromobisphenol A (TBBPA) and
hexabromocyclododecanes (HBCDs) in tissues of humans, dolphins, and sharks from the United States.
Chemosphere 2008, 70, 1935-1944.

Kemi 2006. Survey and Technical Assessment of Alternatives to TBBPA and HBCDD', KEMI Swedish Chemicals
Agency, Jan 2006 http://www.kemi.se/upload/Trycksaker/Pdf/PM/PMl_06.pdf

Kling, P.; Forlin, L. 2009. Proteomic studies in zebrafish liver cells exposed to the brominated flame retardants
HBCD and dTBBPA. Ecotoxicol. Environ. Saf. 2009, 72, 985-1993.

Law, R.J., Herzke, D., Harrad, S., Morris, S., Bersuder, P., and Allchin, C.R. 2008. Levels and trends of HBCD and
BDEs in the European and Asian environments, with some information for other BFRs. Chemosphere 2008, 73,
223-241.

Law, RJ, Bersuder, P., Barry, J., Wilford, B.H., Allchin, C.R. and Jepson, P.D. 2008b. "A Significant Downturn in
Levels of Hexabromocyclododecane in the Blubber of Harbor Porpoises (Phocoena phocoena) Stranded or Bycaught
in the UK: An Update to 2006 Environ. Sci. Technol. 2008, 42, 9104-9109.

Page 10 of 12


-------
Lindberg, P.; Sellstrom, U.; Haggberg, L.; de Wit, C.A.. 2004. Higherbrominated diphenyl ethers and
hexabromocyclododecane found in eggs of peregrine falcons (Falco peregrinus) breeding in Sweden. Environ. Sci.
Technol. 38:93-96.

Morose, G. 2006. An Overview of Alternatives to Tetrabromobisphenol A (TBBPA) and Hexabromocyclododecane
(HBCD)". A Publication of the Lowell Center for Sustainable Production University of Massachusetts - Lowell,
Lowell, MA. http://www.chemicalspolicy.org/downloads/AternativestoTBBPAandHBCD.pdf. (accessed April 1,
2010).

Norden, 2008. Hexabromocyclododecane as a possible global POP. TemaNord 2008:520. Nordic Council of
Ministers, Copenhagen 2007 ISBN 978-92-893-1665-1

Oetken, M.; Ludwichowski, K-U.; Nagel, R. 2001. Validation of the preliminary EU-concept of assessing the
impact of chemicals to organisms in sediment by using selected substances. UBA-FB 299 67 411, Institute of
Hydrobiology, Dresden University of Technology, Dresden, Germany. 2001, pp 97.

Palace, V.P.; Pleskach, K.; Halldorson, T.; Danell, R.; Wautier, K.; Evans, B.; Alaee, M.; Marvin, C.; Tommy, G.T.
2008. Biotransformation enzymes and thyroid axis disruption in juvenile rainbow trout (Oncorhynchus mykiss)
exposed to hexabromocyclododecane diastereoisomers. Environ. Sci. Technol. 2008, 42:1967-1972.

Ronisz, D.; Farmen, E.; Finne, E.;, Karlsson, H.; Forlin, L. 2004. Sublethal effects of the flame retardants
hexabromocyclododecane (HBCDD), and tetrabromobisphenol A (TBBPA), on

hepatic enzymes and other biomarkers in juvenile rainbow trout and feral eelpout. Aquatic Toxicol. 2004,69, 229-
245.

Roosens, L., Abdallah, M.A., Harrad, S., Neels, H. and Covaci, A. 2009. Exposure to Hexabromocyclododecanes
(HBCDs) via Dust Ingestion, but not Diet, Correlates with Concentration in Human Serum—Preliminary Results.
Environ. Health Perspect. doi: 10.1289/ehp.0900869. http://dx.doi.org/. Online 13 July 2009.

Rozman, K. K.; Klaassen, C. D. Absorption, Distribution, and Excretion of Toxicants. In Casarett and Doull's
Toxicology: The Basic Science of Poisons, 6th edition; Seils, A.; Noujaim, S. R.; Sheinis, L. A., Eds.; McGraw-
Hill: New York, 2001; pg 117.

Schriks, M. ; Zninavashe, E. ; Furlow, J.D. ; Murk, A.J. 2006. Disruption of thyroid hormone-mediated Zenopus
laevis tadpole tail tip regression by hexabromocyclododecane (HBCD) and 2,2',3,3',4,4',5,5', 6-nona brominated
diphenyl ether (BDE206). Chemosphere 2006, 65, 1904-1908.

Sellstrom, U.; Soderstrom, G.; deWit, C.; Tysklind, M. 1998. Photolytic debromination of decabromodiphenyl ether
(DeBDE). Organohal. Cmpd 35:447-450.

Sellstrom, U; Bignert, A.; Kierkegaard, A.; Haggberg, L.; de Wit, C.A.; Olsson, M.; Jansson, B.. 2003. Temporal
trend studies on tetra- and pentabrominated ethers and hexabromocyclododecane in Guillemot egg from the Baltic
Sea. Environ. Sci. Technol. 37:5496-5501

Thomsen, C.; Molander, P.; Daae, H. L.; Janak, K.; Froshaug, M.; Liane, V. H.; Thorud, S.; Becher, G.; Dybing, E.
2007. Occupational Exposure to Hexabromocyclododecane At An Industrial Plant. Environ. Sci. Technol. 2007,
41 (15), 5210-5216.

Tomy, G.T.; Budakowski, W.; Halldorson, T.; Whittle, D.M.; Keir, M.J.; Marvin, C.; Macinnis, G.; Alaee, M..
2004. Biomagnification of a- and y-hexabromocyclododecane isomers in a Lake Ontario food web. Environ. Sci.
Tehcnol. 38:2298-2303.

UKEA, 2009. United Kingdom Environment Agency. Hexabromocyclododecane in the Environment.
http://www.environment-agency.gov.uk/business/topics/pollution/39137.aspx

Page 11 of 12


-------
UNECE, 2010. Economic Commission for Europe. Executive Body for CLRTAP; Report of the Executive Body
on its 27th Session. ECE/EB.AIR/99. 9 March 2010, p.9
http://www.unece.org/env/documents/2009/EB/eb/ece.eb.air.99.pdf

UNEP, 2007. Stockholm Convention on Persistent Organic Pollutants. Persistent Organic Pollutants Review
Committee, Third meeting, Geneva, 19-23 November 2007, Item 7 of the provisional agenda, Presentation on
environmental transport and modeling. The OECD screening tool for overall persistence and long-range transport
potential. UNEP/POPS/POPRC. 3/INF/7

UNEP, 2009. Stockholm Convention on Persistent Organic Pollutants. "Summary of the proposal for the listing of
hexabromocyclododecane (HBCDD) in Annex A to the Convention." July 9, 2009.

http://chm.pops.int/Convention/POPsReviewCommittee/hrPOPRCMeetings/POPRC5/POPRC5Followupcommunic
ations/HBCDAnnexEInformationRequest/tabid/645/language/en-US/Default.aspx

UNEP, 2010. Stockholm Convention on Persistent Organic Pollutants. Invitation to review and provide comments
on draft risk profile on hexabromocyclododecane (HBCD).

http://chm.pops.int/Convention/POPsReviewCommittee/hrPOPRCMeetings/POPRC5/POPRC5Followupcommunic
ations/HBCDInvitationforcommentsondraftRP/tabid/742/language/en-US/Default.aspx (accessed April 24, 2010).

US EPA. 2006. U.S. Environmental Protection Agency. Toxic Substance Control Act (TSCA) Chemical Substance
Inventory. 2006 Inventory Update Rule Public Database. Office of Pollution and Prevention of Toxics: Washington,
D.C., 2006.

US EPA, 2008. Exposure Characterization for HPV Challenge Chemical, Exposures to the General Population and
the Environment, March 14, 2008

US EPA, 2010. Integrated Risk Information System. IRISTrack Report for Hexabromocyclododecane Assessment
(http://cfpub.epa.gov/ncea/iristrac/index.cfm?fuseaction=viewChemical.showChemical&sw_id=1102). Accessed
April 6, 2010.

US ITC, 2010. US International Trade Commission. Interactive Tariff and Data Web: US Imports for Consumption.
http://dataweb.usitc.gov/ (accessed April 1, 2010).

US Patent 4980382 - Process for the preparation of expandable vinyl aromatic polymer particles containing
hexabromocyclododecane, http://www.google.com/patents?vid=USPAT4980382

van Leeuwen, S.P., and de Boer, J. 2008. Brominated flame retardants in fish and shellfish - levels and contribution
of fish consumption to dietary exposure of Dutch citizens to HBCD. Mol. Nutr. Food Res. 2008, 52, 194-203.

Veith, G.D.; Defoe, D.L.; Bergstedt, B.V.. 1979. Measuring and estimating the bioconcentration factor in fish. J.
Fish Res. Bd. Can. 36:1040-1048.

Weil E.D.; Levchik, S.V. 2009. Flame Retardants for Plastics and Textiles Practical Applications. Hanser Gardner
Publications. Cincinnati, OH, 2009.

Zhang, X., Yang, F., Zhang, X., Xu, Y., Liao, T., Song, S., Wang J. 2008. Induction of hepatic enzymes and
oxidcative stress in Chinese rare minnow (Gobiocypris rarus) exposed to waterborne hexabromocyclododecane
(HBCD). Aquatic. Toxicol. 2008, 86, 4-11.

Page 12 of 12


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