U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

1 Hexabromocyclododecane (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 human

health concerns based on animal test results indicating potential reproductive, developmental and neurological effects. For these reasons, the Environmental Protection Ag ency (EPA) intends to consider initiating action under the Toxic Substa nces Control Act to address the manufacturing, processing, distribution in co mmerce, and use of HBCD.

As part of the Agency's efforts to addre ss 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 th e existing chemicals program under the Toxic Substances Control Act (TSCA) 1 , the Agency has identified certain widely recognized chemicals, including HBCD, for action plan deve lopment 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 EP A’s initial review of readily available use, exposure, and hazard information on HBCD. EPA considered which of the various authorities provided under TSCA and othe r statutes might be a ppropriate to address potential concerns with HBCD in developing the Action Plan. The Action Plan is intended to describe the courses of action the Agency plan s 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 indicate d by the Action Plan wi ll include appropriate opportunities for public and stakeholder i nput, including through notice and comment rulemaking processes.

III. Scope of Review

HBCD is a category of brominated flame retard ants, consisting of 16 possible isomers. It

has a molecular formula of C 12 H 18 Br 6 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 a ll 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), but both comm ercial products essentially have the same chemical composition. Both CASRNs are listed on the TSCA Inventory. Commerci al preparations of HBCD may contain some possi ble impurities, such as tetrabromocyclododecene or other.

1 15 U.S.C. §2601 et seq.
2 Information on PBT chemicals can be found on the EPA website at: http://www.epa.gov/oppt/newchems/pubs/pbtpolcy.htmU.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

2 isomeric HBCDs (UNEP, 2009). All isomers of HBCD are the subject of this Action Plan, irrespective of the particular CASR N or name used to identify them 3

.

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 decabrom odiphenyl ether (deca-BDE; 26% market share) (Morose, 2006).

The main use of HBCD is as a flame retard ant in expanded polyst yrene foam (EPS) and extruded polystyrene foam (XPS) (Weil and Le vchik, 2009). EPS and XPS are used primarily for thermal insulation boards in the building a nd construction industry (M orose, 2006). HBCD is used because it is highly effective at low c oncentrations; EPS boards contain approximately 0.5% HBCD by weight in the fi nal product (Morose, 2006).

HBCD may also be used as a flame retard ant in the backcoating of textiles for upholstered furniture, upholstery se ating in transportation vehicl es, draperies, wall coverings, mattress ticking, and inte rior textiles such as roller blinds (Morose, 2006; ECHA, 2009). The

maximum concentration of CASRN 3194-55-6 for us e 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 st ringent fire safety la ws of the United Kingdom and California (Morose, 2006). However, accord ing to the 2006 TSCA Inventory Update Rule (IUR) data (which includes information for ch emicals 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, tex tiles and apparel (US EPA, 2006).

In addition, HBCD is used as a flame retard ant 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.) impor t/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 reporte d 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.U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

3 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 note d 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 , dibromoethyldibromocyclohexane and TBBPA), but their effectiveness in this application when compared with HBCD is unknown (Morose, 2006). There are commerci ally available substitutes for XPS and EPS foam board in the construction process that do no t 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 alternativ es for HBCD in textile applications. For textile backing, these include deca-BDE, chloroparaffins and ammonium polyphosphate (ECHA, 2009). There are several alternat ives 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 chlo roparaffins may not be suitable for use as substitutes for HBCD since EPA has already developed Action Plans for these chemicals due to concerns about their persiste nt, bioaccumulative and toxic properties. Other chemicals used in HIPS include both halogenate d 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. Bioaccumulation was observed to be higher in female than male rats. The elimination of HBCD from body fat is markedly slower than

from other tissues with an elimin ation half-life of week s to months (Chengelis, 2001). Repeated exposure of HBCD to rats showed disturbances in thyroid hormone system and effects on the thyroid males and females (Chengelis, 2001). A study by Eriksson, et al. (2006), concluded that neonatal exposure of HBCD to mice affected s pontaneous motor behavior , learning and memory processes in adult mice. However, this study was not conducted according to established 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 significan t decrease in the number of pr imordial follicles in the F1 females). Although this decrease in ovarian follicles di d 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 and memory in F1 males, but exposure did not cause any changes in spontaneous behavior. In a ddition, there was high and dose- dependent pup mortality during lactation (Ema, et al., 2008).U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

4 Environmental Effects

Laboratory studies have shown that HBCD is capable of pr oducing adverse effects in a variety of organisms including algae, fish, invertebrates and soil-dwelling organisms at environmentally relevant concentr ations. HBCD is toxic to al gae and acutely toxic to fish embryos (Desjardins, et al., 2004; Deng, et al., 2009). A number of sub-lethal effects have also been observed in fish (Palace, et al., 2008; Kling and Förlin, 2009; Zhang, et al., 2008; Ronisz, et al., 2004). Drottar and Krueger (1 998) reported a reduced number and size of daphnid offspring in first and second generations. Thyroid hor mone-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 lowe r biomass in soil dwelling organisms ( Lumbriculus variegatus ) (Oetken, et al., 2001). HBCD administered to chicken ( Gallus domesticus ) embryonic hepatocytes in vitro resulted in significant alterati ons in expression of genes (mRNA) associated with liver and thyr oid function (Crump, et al., 2008 ). Thinner egg shells were measured in American kestrels exposed to a co mbination of PBDEs and HBCD (Fernie, et al., 2009).

VI. Physical-Chemical Properties a nd Fate Characterization Summary

The members of the HBCD flame retardants category are solids with negligible to low vapor pressure and negligible to low water solu bility. [Molecular Weight = 642; Melting Point = 175 - 190 °C; Vapor Pressure < 5 x 10-7 mm Hg at 20°C; log K

ow = 5.8; and Water Solubility < 50 ppb ( μ g/L) (EC 2000; EC 2008; Guerra, et al., 2009)]

Persistence

Limited data are available on the degradati on 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 acc ording to half-life criteria set forth in the PMN program (64 FR 60194, November 4, 1999) and inte rnational Persistent Organic Pollutants (POPs) protocols (UNEP, 2007; Norden, 2008). Ho wever, environmental monitoring data shows frequent occurrence of HBCD in biota over la rge areas and in remote locations where no demonstrable sources have been shown to account for the exposures (see discussion of environmental exposures in Sect ion VII below), supporting the findi ng that HBCD is sufficiently persistent to be of concern within the scope of these international protocols. Measured levels of HBCD in dated sediment core samples also prov ide evidence of persistence. The frequent detection of HBCD over a large geographic area, with increasing exposure in remote locations such as the Arctic, where no demonstrable lo cal sources exist that can account for these exposures, suggest that HBCD is persistent and undergoes long -range atmospheric transport.U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

5 Bioaccumulation

HBCD has high bioaccumulation potential. 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 Swedis h monitoring study (Sellstrom, et al. 1998), a fishto-sediment ratio (biota/sediment accumulation fa ctor; BSAF) of 15 was reported for one of two sites, indicating that HBCD is bioavaila ble 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 populati ons feeding on chickens (Lindberg, et al., 2004) or guillemot from the Baltic Sea (Sellstrom, et al., 2003), demonstrati ng that HBCD may also bioaccumulate in terrestrial organisms and food chains.

VII. Exposure Characterization Summary

Releases

HBCD is not reported in the T oxics Release Inventory. No readily available quantitative

release information in the U.S. was found. EC HA 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). Th e overall volume used in 2007 was estimated at 11.6 million kg/year (ECHA, 2009). A Swedish articl e 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 applicati on in the U.S. is estimated to be < 1 % of the total volume of HBCD produced/imported and hence releases from th is 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 environmen t from the finished products in use or after disposal (US EPA, 2008b). EC HA states: “A substantial pr oportion of articles containing HBCD will have very long service life (30+ year s for typical insulation like EPS and XPS) and environmental releases will continue for a long ti me into the future.” (ECHA, 2009). It is not known how comparable the releas es of HBCD from manufacturi ng and use operations in the U.S. are to those reported in Europe.

Human Exposure

HBCD is typically manufactured as a pow der of approximately 100 microns in size; however, a portion of the materials is micronize d to 1 micron during manufacture (U.S. Patent 4980382), which poses the potential of deep lung particulate exposure (Rozman, et al., 2001)).U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

6 Workers who do not wear appropri ate respiratory protection have the high potential for deep lung exposure of the 1 micron material. Particles 1 micron and smaller pene trate 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 cleare d, and the portion remaining longer than 24 hours is cleared very slowly. Some particles may remain in the alveoli indefinitely (R ozman, et al., 2001). Commercial workers also may ha ve potential dermal and inhala tion exposure to the chemical during application. The Occupational Safety and Health Administration (OSHA) has not established a Permissible Exposure Limit for H BCD. An occupational exposure study at an industrial plant in Europe producing EPS, reporte d measured elevated ai rborne dust levels and measured HBCD in the blood of workers (Thomse n, et al., 2007). No re adily available HBCD occupational exposure informati on (including biomonitoring data) was found for U.S. workers. Based on available IUR reporting, the maximum tota l 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 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 Ve tter, 2007; Fernandes, et al., 2008; van Leeuwen and de Boer, 2008), outdoor air, particularly near poi nt sources (Covaci, et al., 2006), and indoor air (Law, et al., 2008). HBCD has also been det ected 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 applicati ons (e.g., building foam, furnitur e upholstery, carpeting), children could be exposed, especially given children’s incr eased exposure via dust and the hand-to-mouth ingestion pathway. In vitro experiments conducted to demons trate leaching of HBCD from textiles showed that the presence of simulated bi ological fluids (sweat, sa liva) and fruit juices enhances the leaching of HBCD from back-c oated samples (Ghanem, 2009). Children’s exposure to HBCD from mouthing of textiles and from pica 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 invertebrate s, 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 fi sh, ringed seals and polar bears (UNEP, 2009). It has been detected in freshw ater, marine, and avian organisms, and in upper trophic-level mammals (polar bears and seals). The majority of th ese studies are European, some are from North America, and a few are from Asia. A study repor ted decreased levels of HBCD in biota once a United Kingdom manufacturi ng plant was closed (Law, et al., 2008b).U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

7 VIII. Risk Management Considerations

HBCD is of international concern because of its PBT properties. HBCD is on the ECHA’s list of Substances of Very High Concer n (SVHCs). HBCD is under consideration for listing under the POPs Protocol to the Conven tion on Long-Range Transboundary Air Pollution,

as technical review has conclude d that HBCD is persistent, bioaccumulative, can cause adverse effects to humans or the environment, and has the potential to be tr ansported long distances within the meaning of the Pr otocol (UNECE, 2010). Unde r the Stockholm Convention for Persistent Organic Pollutants, the POPs Revi ew 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 aquati c organisms. HBCD biomagnifies in food chains. Given its presen ce at increasing levels in the environment including wildlife, and th e high hazard for HBCD to algae an d aquatic invertebrates, EPA has a concern for the potential risk to these aquatic organisms.

EPA has presented evidence which strongly sugg ests 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 show s repeated dose toxicity. There may be some human health hazard concern based on thyroid effects and indications of developmental and

transient neurobehavioral effects. These hea lth effects combined with potential exposures suggests some concern for a potential risk to th e general population from HBCD is warranted.

Greater concern is warranted for workers w ho 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 othe r, 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 that could provide direct 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 protecti ng children’s health. Thes e factors suggest that concerns for potential risks to children and pregnant women should be considered with any actions taken to manage this chemical.U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

8 IX. Next Steps

In conducting this review of HBCD, EPA considered a number of potential risk management actions, including regulatory acti ons 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 h azard 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 comm ercial HBCD. In addition, as part of the Agency’s efforts to address these chemical substa nces, 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:

 Initiate rulemaking under TSCA Section 5(b )(4) of TSCA to add HBCD to the list of chemicals which present or may present an unrea sonable risk of injury to health or the environment. EPA intends to publish a no tice of proposed rulemaking by the end of

2011.

 Initiate rulemaking under TSCA section 5(a)(2 ) to designate manuf acture 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 th e 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 consid er initiating rulemaki ng under TSCA section 6(a) to address general consumer textile use.

 Consider rulemaking under TSCA section 6(a) to regulate HBCD. A section 6(a) action could take the form of a comprehens ive 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.

 Inititate rulemaking in late 2011 to add HBCD to the Toxics Release Inventory. HBCD is currently not listed by any CASRN on th e Emergency Planning and Community Rightto-Know (EPCRA) section 313 list of toxi c substances. Listing will require manufacturers or importers to provide envi ronmental release information not currently captured by IUR.

 Conduct a Design for the Environment and Gree n Chemistry alternatives assessment of HBCD. The information developed could be used to encourage i ndustry to move awayU.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

9 from HBCD instead of, in addition to, or as part of any regulatory action taken under

TSCA. The alternatives assessment woul d build upon existing knowledge and would consider various exposed populations, includ ing sensitive human subpopulations, as well as environmental exposure. The work will begin in 2011, with completion expected in

2013.U.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

10 X. References

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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., K ohler, 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 dom esticus) 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 [ 14 C]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: Netherla nds Institute for Fisheries Re search (RIVO) BV. Report

number C033/02.

Deng, J. ; Yu, L, ; Liu, C. ; Yu , K. ; Shi,, X. ; Ye ung, L.W.Y. ; Lam, P.K.S. ; Wu, R.S.S. ;Zhou B. 2009. Hexabromcyclododecane-induced developmen tal toxicity and apoptosis in zebra fish 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 Re port. Wildlife International, Ltd., Easton, Maryland, USA. pp 66.

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

Drottar, K.R.; MacGregor, J.A.; Kr ueger, H.O. 2001. Hexa bromocyclododecane (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.

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

EC 2008. European Commission. Ri sk Assessment: Hexabromocyclododecan e CAS-No.: 25637-99-4 EINECS-No.: 247-148-4, Final Report May 2008. Offi ce for Official Publications of th e European Communities: Luxembourg,

2008.

ECHA, 2009. European Chemicals Agen cy. Data on Manufacture, Import, Ex port Uses and Releases of HBCDD as

well as Information on Potential Alternativ es to Its Use. December 1, 2009. http://echa.europa.eu/doc/consultations/reco mmendations/tech_reports/tech_rep_hbcdd.pdfU.S. Environmental Protection Agency OMB Review Draft, 04/28/10 U.S. Government Internal Deliberative Document, Do Not Quote, Cite, or Release

11 Ema, M., Fujii, S., Hirata-Koizumi, M., and Matsumoto, K. 2008. Two-generation reproductive toxicity study of the flame retardant hexabromcyclododecane in ra ts. Reproductive Toxi cology, 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 hexabromocyc lododecane (HBCDD). Environ. Toxicol. Pharmacol. 2006, 21, 317-322.

Fernandes, A., Dicks, P., Mortimer, D., Gem, M., Sm ith, 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. En vironmentally 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 Hexabromocyc lododecane 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.

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