F or other data, click on the Table of Contents

Environmental Fate & Exposure:

Environmental Fate/Exposure Summary: 1,2,5,6,9,10- Hexabromocyclododecane 's production and use as a flame retardant may result in its release to the environment through various waste streams. If released to air, a vapor pres sure of 4.7X10-7 mm Hg at 21 deg C indicates 1,2,5,6,9,10- hexabromocyclododecane will exist in both the vapor and particulate phases in the atmosphere. Vapor-phase 1,2,5,6,9,10- hexabromocyclododecane will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for th is reaction in air is estimated to be 3 days. Particulate- phase 1,2,5,6,9,10- hexabromocyclododecane will be removed from the atmo sphere by wet or dry deposition. 1,2,5,6,9,10- Hexabromocyclododecane does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunligh t. If released to soil, 1,2,5,6,9,10- hexabromocyclododecane is expected to be immobile based upon an estimated Koc of 59,000. Volatilization from moist soil surfaces is expected to be an important fate process based upon an estimate d Henry's Law constant of 4.6X10-5 atm-cu m/mole. However, adsor ption to soil is expected to attenuate volatilization. Biodegradation data were not available. If released into water, 1,2,5,6,9,10- hexabromocyclododecane is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expecte d to be an important fate process based upon this compound's estima ted Henry's Law constant. Estimated volat ilization half-lives for a model river a nd model lake are 2 days and 25 days, respectively. However, volatilization from water surfaces is expected to be attenuated by adsorption to suspe nded solids and sediment in the water column. The estimated volatilization half- life from a model pond is 14 years if adsorption is considered. A BCF of 18,100 suggests that bioconcentration in aquatic organisms is very high, provided the compound is not metabolized by the organism. Hyd rolysis is not expected to be an important environmental fate process sin ce this compound lacks functional groups that hydrolyze under environ mental conditions. Occupational exposure to 1,2,5,6,9,10- hexabromocyclododecane may occur through inhalation and dermal contact with this compound at workplaces where 1,2,5,6,9,10- hexabromocyclododecane is produced or used. Use data indicate that the general population may be exposed to 1,2,5,6,9,10- hexabromocyclododecane via dermal contact with consumer products containing 1,2,5,6,9,10- hexabromocyclododecane . (SRC)
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Probable Routes of Human Exposure: Occupational exposure to 1,2,5,6,9,10- hexabromocyclododecane may occur through inhalation and dermal contact with this compound at workplaces where 1,2,5,6,9,10- hexabromocyclododecane is produced or used. Use data indicate that the general population may be exposed to 1,2,5,6,9,10- hexabromocyclododecane via dermal contact with consumer products containing 1,2,5,6,9,10- hexabromocyclododecane . (SRC)

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... The National Occupational Exposure Survey (NOES), a survey conducted from 1981 to 1983, has no data for the total number of workers potentially exposed to this chemical under CAS number 3194-55-6 (specifically 1,2,5,6,9,10- HBCD ); however, the NOES estimated a total of 11,921 workers potentially exposed to this chemical under CAS number 25637-99-4. Based on IUR reporting, which included at leas t one report that worker information was not readily obtainable, the maximum total number of workers likely to be exposed to this chemical during manufacturing and industrial processing and use is between 100 and 999. [US EPA; Risk-Based Prioritization Document. Initial Risk-Based Prioritization of High Production Volume Chemicals. Chemical Category: Hexabromocyclododecane (HBCD). CAS 3194-55-6 1,2,5,6,9,10-hexabromocyclododecane; CAS 25637-99-4 hexabromocyclododecane. 3/18/2008.] **PEER REVIEWED**

Artificial Pollution Sources: 1,2,5,6,9,10- Hexabromocyclododecane 's production and use as an additive flame retardant fo r extruded and expanded polystyrene foam as well as crystal and high-impact polystyrene, SAN (Styrene-AcryloNitrile) re sins, adhesives, and coatings(1), may result in its release to the environment through various waste streams(SRC). [(1) Ullmann's Encyclopedia of Industrial Chemistry. 6th ed. Vol 1: Federal Republic of Germany: Wiley-VCH Verlag GmbH & Co. 2003 to Present. V5: 626 (2003] **PEER REVIEWED**

Environmental Fate: TERRESTRIAL FATE: Based on a classification scheme(1), an estima ted Koc value of 59,000(SRC), determined from a water solubilit y of 8.6X10- 3 mg/L(2) and a regression-derive d equation(3), indicates that 1,2,5,6,9,10- hexabromocyclododecane is expected to be immobile in soil(SRC). Volatilization of 1,2,5,6,9,10- hexabromocyclododecane from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.6X10-5 atm-cu m/mole(SRC), derived from its vapor pressure, 4.7X10-7 mm Hg(4), and water so lubility(2). However, adsorption to soil is expected to attenuate volatilization(SRC). 1,2,5,6,9,10- Hexabromocyclododecane is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). Biodegradation data were not available(SRC, 2009). [(1) Swann RL et al; Res Rev 85: 17-28 (1983) (2) Great Lakes Chem Corp; Water Solubility of Several Industrial Chemicals Flame Retardants and a Herbicide VEL-3510; 3/13/90; EPA Document No. 86-900000270; Fiche No. OTS0523262. (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-5 (1990) (4) Chem Manuf Assoc; Hexabromocyclododecane (HBCD): Determination of the Vapor Pressure Using a Spinning Rotor Gauge; 8/19/97; 1,2,5,6,9,10-HEXABROMOCYCLODODECANE CASRN: 3194-55-6 

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5/31/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search/f?./tem p /~80 q PcS:1:BASICEPA Document No. 86-70000839; Fiche No. OTS0573702.] **PEER REVIEWED**

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 59,000(SRC), determin ed from a water solubility of 8.6X10-3 mg/L(2) and a regression-derived equation(3), indicates that 1,2,5,6,9,10- hexabromocyclododecane is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3 ) based upon an estimated Henry's Law constant of 4.6X10-5 atm-c u m/mole(SRC), derived from its vapor pressure, 4.7X10-7 mm Hg(4), and water so lubility(2). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2 and 25 days, respectively(SRC). However, volatilization from w ater surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. The estimated volatilization half -life from a model pond is 14 years if adsorption is considered(5). According to a classification scheme(6), a BCF of 18,100 in fathead minnows(7) , suggests the potential for bioconcentration in aquatic organisms is very hi gh, provided the compound is not metabolized by the organism(SRC) . Biodegradation data were not available(SRC, 2009). [(1) Swann RL et al; Res Rev 85: 17-28 (1983) (2) Great Lakes Chem Corp; Water Solubility of Several Industrial Chemicals Flame Retardants and a Herbicide VEL-3510; 3/13/90; EPA Document No. 86-900000270; Fiche No. OTS0523262. (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-5, 15-1 to 15-29 (1990) (4) Chem Manuf Assoc; Hexabromocyclododecane (HBCD): Determination of the Vapor Pressure Using a Spinning Rotor Gauge; 8/19/97; EPA Document No. 86-70000839; Fiche No. OTS0573702. (5) US EPA; EXAMS II Computer Simulation (1987) (6) Franke C et al; Chemosphere 29: 1501-14 (1994) (7) Veith GD et al; J Fish Res Board Can, 36: 1040-8 (1979)] **PEER
REVIEWED**

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,2 ,5,6,9,10- hexabromocyclododecane , which has a vapor pressure of 4.7X10-7 mm Hg at 21 deg C(2) , will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 1,2,5,6,9,10- hexabromocyclododecane is degraded in the atmosphere by reaction with photochemically- p roduced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 3 days(SRC), calculated from its rate constan t of 5.01X10-12 cu cm/molecule-sec at 25 deg C(SRC) that was derived using a st ructure estimation method(3). Particulate-phase 1,2,5,6,9,10- hexabromocyclododecane may be removed from the air by wet or dry deposition(SRC). 1,2,5,6,9,10- Hexabromocyclododecane does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunl ight(SRC). [(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988) (2) Chem Manuf Assoc; Hexabromocyclododecane (HBCD): Determination of the Vapor Pressure Using a Spinning Rotor Gauge; 8/19/97; EPA Document No. 86-70000839; Fiche No. OTS0573702. (4) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 8-12 (1990)] **PEER REVIEWED**

Environmental Abiotic Degradation: The rate constant for the vapor-phase reaction of 1,2,5,6,9,10- hexabromocyclododecane with photochemically-produced hydroxyl radicals has been estimated as 5.01X10-12 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimati on method(1). This corresponds to an atmo spheric half-life of about 3 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 1,2,5,6,9,10- Hexabromocyclododecane is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 1,2,5,6,9,10- Hexabromocyclododecane does not contain chromophores that absorb at wavelengths >290 nm(3) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC). [(1) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993) (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5, 8-12 (1990)] **PEER REVIEWED**

Environmental Bioconcentration: A BCF of 18,100, was measured in fathead minnows during a 32 day e xposure at 6.2 ug/L(1). According to a classification scheme( 2), this BCF suggests the potential for bioconcentration in aquatic organisms is very high, provided the compound is not metabolized by the organism(SRC). [(1) Veith GD et al; J Fish Res Board Can,36: 1040-8 (1979) (2) Franke C et al; Chemosphere 29: 1501-14 (1994)] **PEER
REVIEWED**

Soil Adsorption/Mobility: The Koc of 1,2,5,6,9,10- hexabromocyclododecane is estimated as 59,000(SRC), using a water so lubility of 8.6X10-3 mg/L(1) and a regressionderived equation(2). According to a classification sc heme(3), this estimated Koc value suggests that 1,2,5,6,9,10- hexabromocyclododecane is expected to be immobile in soil. [(1) Great Lakes Chem Corp; Water Solubility of Several Industrial Chemicals Flame Retardants and a Herbicide VEL-3510; 3/13/90; EPA Document No. 86-900000270; Fiche No. OTS0523262. (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-5 (1990) (3) Swann RL et al; Res Rev 85: 17-28 (1983)] **PEER
REVIEWED**

Volatilization from Water/Soil: The Henry's Law constant for 1,2,5,6,9,10- hexabromocyclododecane is estimated as 4.6X10-5 atm-cu m/mole(SRC) derived from its vapor pressure, 4.7X10-7 mm Hg(1), and water solubility, 8.6X10-3 mg /L(2). This Henry's Law constant indicates that 1,2,5,6,9,10- hexabromocyclododecane is expected to volatilize from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/s ec)(3) is estimated as 2 days(SRC ). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is es timated as 25 days days(SRC). However, volatilization from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. The estimated volatilization half-life fro m a model pond is 14 years if adsorption is considered(4). 1,2,5,6,9,10- Hexabromocyclododecane 's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 1,2,5,6,9,10- Hexabromocyclododecane is not expected to volatilize from dry soil surfaces(SRC) based upon it vapor pressure(1). [(1) Chem Manuf Assoc; Hexabromocyclododecane (HBCD): Determination of the Vapor Pressure Using a Spinning Rotor Gauge; 8/19/97; EPA Document No. 86-70000839; Fiche No. OTS0573702. (2) Great Lakes Chem Corp; Water Solubility of Several Industrial Chemicals Flame Retardants and a Herbicide VEL-3510; 3/13/90; EPA Document No. 86-900000270; Fiche No. OTS0523262. (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990) (4) US EPA; EXAMS II Computer Simulation (1987)] **PEER REVIEWED** 

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5/31/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search/f?./tem p /~80 q PcS:1:BASICChemical/Ph y sical Properties:

Molecular Formula: C12-H18-Br6
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Molecular Weight: 631.69 [Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 462] **PEER REVIEWED**

Color/Form: Crystals [Lide, D.R. CRC Handbook of Chemistry and Physics 88TH Edition 2007-2008. CRC Press, Taylor & Francis, Boca Raton, FL 2007, p. 3-276] **PEER REVIEWED**

Solid [Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 462] **PEER REVIEWED**

Melting Point: 167 deg C [Lide, D.R. CRC Handbook of Chemistry and Physics 88TH Edition 2007-2008. CRC Press, Taylor & Francis, Boca Raton, FL 2007, p. 3-276] **PEER REVIEWED**

Octanol/Water Partition Coefficient: log Kow = 7.74 (est) [US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.0. Jan, 2009. Available from, as of Feb 26, 2009: http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm **PEER REVIEWED**

Solubilities: Soluble in ketone, chlorinated and aromatic solvents. [Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 462] **PEER REVIEWED**

In water, 8.6X10-3 mg/L at 25 deg C [Great Lakes Chem Corp; Water Solubility of Several Industrial Chemicals Flame Retardants and a Herbicide VEL-3510; 3/13/90; EPA Document No. 86-900000270; Fiche No. OTS0523262] **PEER REVIEWED**

Vapor Pressure: 4.7X10-7 mm Hg at 21 deg C [Chem Manuf Assoc; Hexabromocyclododecane (HBCD): Determination of the Vapor Pressure Using a Spinning Rotor Gauge; 8/19/97; EPA Document No. 86-70000839; Fiche No. OTS0573702] **PEER REVIEWED**

Other Chemical/Physical Properties: Bromine content = 74.7% /Commercial mixture/ [Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA4: 415 (1985)] **PEER REVIEWED**

Melting point = 170-180 deg C /Commercial mixture/ [Dagani, MJ et al; Ullmann's Encyclopedia of Industrial Chemistry. 7th ed. (2008). NY, NY: John Wiley & Sons; Bromine Compounds. Online Posting Date: Jun 15, 2000.] **PEER REVIEWED**

Henry's Law constant = 4.6X10-5 atm-cu cm/mole at 25 deg C (est) [SRC; The Physical Properties Database (PHYSPROP). Syracuse, NY: Syracuse Res Corp. Available from, as of Feb 26, 2009: http://www.syrres.com/what

- we

- do/product.aspx?id=133n **PEER REVIEWED**

Hydroxyl radical reaction rate constant = 5.01X10-12 cu cm/molec-sec at 25 deg C (est) [US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.0. Jan, 2009. Available from, as of Feb 26, 2009: http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm **PEER REVIEWED**

Manufacturing/Use Information:

Major Uses: The main use for HBCD /1,2,5,6,9,10- hexabromocyclododecane / is as an additive-type flame retardant for extruded and expanded polystyrene foam. Other applications include crystal and high-impact polystyre ne, SAN (Styrene-AcryloNitrile) resins, adhesives, and coatin gs. [Ullmann's Encyclopedia of Industrial Chemistry. 6th ed.Vol 1: Federal Republic of Germany: Wiley-VCH Verlag GmbH & Co. 

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Methods of Manufacturing: ... Produced by the addition reaction of bromine to trans, tran s, cis-1,5,9-cyclododecatriene, the cyclic trimer of butadiene. The hexabromocyclododecane that is obtained from this reaction consists of a mixture of stereoisomers of 1,2,5,6,9,10- hexabromocyclododecane ranging from oils to an isomer with a 205-208 deg C melting point. Commercially available hexabromocyclododecane contains a mixture of solid isomers and has a melting point range of 170-180 deg C (185-195 deg C). [Ullmann's Encyclopedia of Industrial Chemistry. 6th ed.Vol 1: Federal Republic of Germany: Wiley-VCH Verlag GmbH & Co. 2003 to Present, p. V5 625 (2003)] **PEER REVIEWED**

General Manufacturing Information: Additive flame retardant used in low-density polystyrene foam...a dequate to produce foam that meets building code requirements in the U.S. [Sutker BJ; Ullmann's Encyclopedia of Industrial Chemistry. 7th ed. (2008). NY, NY: John Wiley & Sons; Flame Retardants. Online Posting Date: Jun 15, 2000.] **PEER REVIEWED**

U. S. Production: Cyclododecane, 1,2,5,6,9,10-hexabromo- is listed as a High Production Volume (HPV) chemical (65FR81686). Chemicals listed as HP V were produced in or imported into the U.S. in >1 million pounds in 1990 and/or 1994. The HPV list is based on the 1990 Inventory Upd ate Rule. (IUR) (40 CFR part 710 subpart B; 51FR21438). [EPA/Office of Pollution Prevention and Toxics; High Production Volume (HPV) Challenge Program. Available from the Database Query page at: http://www.epa.gov/hpv/pubs/general/opptsrch.htm on Cyclododecane, 1,2,5,6,9,10-hexabromo- (3194-55-6) as of February 18, 2009] **PEER REVIEWED**

Production volumes for non-confidential chemical s reported under the Inventory Update Rule.

[US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclododecane, 1,2,5,6,9,10-hexabromo- (3194-55-6). Available from, as of February 18, 2009: http://www.epa.gov/oppt/iur/tools/data/2002

- vol.html **PEER REVIEWED**

... manufactured or imported in the US between 10 and 50 million pounds in 2005. [US EPA; Risk-Based Prioritization Document. Initial Risk-Based Prioritization of High Production Volume Chemicals. Chemical Category: Hexabromocyclododecane (HBCD). CAS 3194-55-6 1,2,5,6,9,10-hexabromocyclododecane; CAS 25637-99-4 hexabromocyclododecane. 3/18/2008.] **PEER REVIEWED**

Synonyms and Identifiers:

Synonyms: CYCLODODECANE, 1,2,5,6,9,10-HEXABROMO-
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Hexabromid S
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Hazardous Substances Databank Number: 6110

Last Review Date: Reviewed by SRP on 5/7/2009 Year Production Ran g e (pounds)

1986 >1 million - 10 million

1990 >1 million - 10 million

1994 >10 million - 50 million

1998 >10 million - 50 million

2002 >10 million - 50 million 

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### Environmental Fate & Exposure:

Environmental Fate/Exposure Summary: Hexabromocyclododecance's production and wide use as a brominated fl ame retardant may result in its release to the environment through various waste streams. If rel eased to air, a vapor pressure of 4.72X10-6 mm Hg at 25 deg C indicates hexabromocyclododecance will exist in both the vapor a nd particulate phases in the atmosphere. Vapor-phase hexabromocyclododecance will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in ai r is estimated to be 3 days. Particulate-phase hexabromocyclododecance will be removed from th e atmosphere by wet or dry deposition. Hexabromocyclododecance does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, hexabromocyclododecan ce is expected to be immobile based upon an estimated Koc of 27,000. Vola tilization from moist soil surfaces is expected to be an important fate process based upon an estimated Henry's Law consta nt of 6.1X10-4 atm-cu m/mole. Ho wever, adsorption to soil is expected to attenuate volatilization. A half-life of 210 days in sediment indicates that biode gradation is not an important environmental fate process. If released into water, hexabrom ocyclododecance is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water su rfaces is expected to be an important fate process based upo n this compound's estimated Henry's Law consta nt. Using this Henry's Law constant and an estimation method, volatilization halflives for a model river and model lake are 11 hours and 11 days , respectively. However, volatili zation from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. The estimated volatilization half

life from a model pond is 16 months if adsorption is c onsidered. Reported BCF values of 18,197 and 8,974 suggest that bioconcentration in aquatic organisms is very high, provided the compound is not metabol ized by the organism. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functi onal groups that hydrolyze under environmental conditions. Occupational exposure to hexabromoc yclododecance may occur through inhalation and dermal contact with this compound at workplaces where hexabromocyclododecance is produced or used. Monitoring data indicate that the general
p opulation may be exposed to hexabromocyclododecance via ingestion. (SRC)

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Probable Routes of Human Exposure: N IOSH (NOES Survey 1981-1983) has statistically estimated that 11,921 workers (6,962 of these were female) were potentially exposed to hexabromocyclododecance in the US(1). Occupati onal exposure to hexabromocyclododecance may occur through inhalation and dermal contact with this compound at workplaces where hexabromocyclododecance is produced or used(SRC). Monitoring data indicate that the general population may be expos ed to hexabromocyclododecance via ingestion of fish(SRC). [(1) NIOSH; NOES. National Occupational Exposure Survey conducted from 1981-1983. Estimated numbers of employees potentially exposed to specific agents by 2-digit standard industrial classification (SIC). Available at http://www.cdc.gov/noes/ as of Feb 20, 2009.] **PEER REVIEWED**

Body Burden: Median hexabromocyclododecane plasma levels in 2002 from 10 pregnant women living in Bodo, Norway were 19, 7, and 23
p g/mL plasma for the alpha-, beta-, and gamma-isomers, respectivel y; levels of plasma samples from 10 women living in Taimyr, Russia were 21, 8, and 33 pg/mL plasma, respectively(1). Hexabromocyclododecane levels in mothers' milk from the Stockholm, Sweden area increased from 0.13 pmol/g lipid in 1980 to 0.60 pmol/g lipid in 2004, with the highest levels reported in 2001 and 2002, 0.83 and 0.93 pmol/g lipid, respectively. Levels in Norwegia n breast milk samples ranged from 0.25-2 ng/g lipids over a study period of 1986-2001(1). [(1) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009.] **PEER
REVIEWED** 

### HEXABROMOCYCLODODECANE CASRN: 25637-99-4 

### Pa g e 1 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/searchThe National Food Administration in Sweden has analyzed HBCDD and other substances in mother's milk from Swedish women in two different studies. The first study de tected HBCDD in 12 of 33 samples. The samples were taken from primiparous, age 19- 40, living in Uppsala County, Sweden, two w eeks after delivery. The limit of detect ion was /leas than/ 15 pg HBCDD/g mothers milk (fresh weight). On a lipid weight basis, the mean and max concentrations were 0.45 and 2.4 ng/g fat, respectively. [European Chemicals Bureau; European Union Risk Assessment Report, hexabromocycleododecane, (25637-99-4) (2008). Available from, as of February 25, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Hexabromocyclododecane ( HBCD ) is a type of brominated flame retardant. We i nvestigated the time tre nd of the stereoisomerspecific concentrations of HBCD (alpha, beta, and gamma) in breast milk samples of Japanese women by using liquid chromatography-tandem mass spectrometry (LC/MS/MS). Th e pooled milk lipid samples collected in 1973, 1978, 1983, 1988, 1993, 1999, and from 2000 to 2006 were analysed. The concentration was below the detection limit in the samples collected between 1973 and 1983 and increased in those collected since 1988. Between 1988 and 2006, alpha- HBCD was detected in all 11 breast milk samples collected from 25 to 29-year-old Japanese women; gamma- HBCD , in 7; and beta- HBCD , in none of the samples. Time trend of summation operatorHBCD app eared to be related to that of the industrial HBCD consumption level in Japan. [Kakimoto K et al; Chemosphere 71(6): 110-4 (2008).] **PEER REVIEWED** PubMed Abstract

The level in adipose tissue was 0.3-0.7 mg/g fat. [EPA/Office of Pollution Prevention and Toxics; High Production Volume Information System (HPVIS) on Cyclododecane, hexabromo- (25637-99-4). Available from, as of February 26, 2009: http://www.epa.gov/hpvis/index.html **PEER REVIEWED**

Concentrations of tetrabromobisphenol A (TBBPA) and alpha-, beta-, and gamma-isomers of hexabromocyclododecanes (HBCDs) were determined by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS ) in human adipose tissue obtained in New York City. ... The overall mean concentr ations (mean+/-SD) of TBBP A and HBCDs were 0.048+/-0.102 and 0.333+/-0.571 ng/g lipid wt in human adipose tissue samples. ... Over all mean concentrations of HBCDs were 5-10-fold higher than mean TBBPA concentrations, in all of the samples analyze d. ... In the human adipose tissue samples, the concentrations of HBCDs were 3-4 orders of magnitude lower than the concentr ations of polybrominated diphenyl ethers (PBDEs) previously reported for the same set of tissue samples. Concentrations of HBCDs in human samples from the United States were 1-5-fold lower than the concentrations reported from several European countries. [Johnson-Restrepo B et al; Chemosphere 70(11): 1935-44 (2008).] **PEER REVIEWED** PubMed Abstract

Average Daily Intake: The estimated UK upper bound average dietary intake in 2004 was 413 ng total hexabromocyclododecanes/day for a 70 kg adult and 240 ng/day for a 10 kg toddler(1). The maximum daily intake for hexabromocyclododecane is 22 ng/kg/day, based on studies on food samples bought in food stores in Sweden(2). The averag e daily intake by the Dutch population was calculated at 2.9 ng/k g bwt/day, based on 91 samples from dairy, meat, anim al fat, eggs, fish and vegetable oil(2). [(1) Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008) (2) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009.] **PEER
REVIEWED**

Artificial Pollution Sources: Hexabromocyclododecance's production and wide use as a brominat ed flame retardant(1,2) may result in its release to the environment through various waste streams(SRC). [(1) Janek K et al; Environ Sci Technol 39: 1987-94 (2005) (2) Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED**

Environmental Fate: TERRESTRIAL FATE: Based on a cl assification scheme(1), an estimated Koc va lue of 27,000(SRC), determined from a log Kow of 5.63(2) and a regression-derive d equation(3), indicates that hexabromocyclododecane is expected to be immobile in soil (SRC). Volatilization of hexabromocyclododecane from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 6.1X10-4 atm-cu m/mole( SRC), derived from its vapor pressure, 4.72X10-6 mm Hg (2), and water solubility, 6.56X10-3 mg/L(2). However, adsorpti on to soil is expected to attenuate volatilization(SRC). Hexabromocyclododecane is not expected to volatilize from dry soil surfaces (SRC) based upon its vapor pressure(2). A half-life of 63 days in soil(2) indicates that biodegradation is not an important environmental fate process in soil(SRC). [(1) Swann RL et al; Res Rev 85: 17-28 (1983) (2) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246- 148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009. (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-9 (1990)]
**PEER REVIEWED** 

### Pa g e 2 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/searchAQUATIC FATE: Based on a classification scheme(1), an estim ated Koc value of 27,000(SRC), determined from a log Kow of 5.63(2) and a regression-derived equation(3), indicates that hexabromocyclododecane is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expect ed(3) based upon an estimated Henry's Law constant of 6.1X10-4 atm-cu m/mole(SRC), derived from its va por pressure, 4.72X10-6 mm Hg(2), and wate r solubility, 6.56X10-3 mg/L(2). Using this Henry's Law constant and an estimation me thod(3), volatilization ha lf-lives for a model river a nd model lake are 11 hours and 1 1 days, respectively(SRC). However, volatilization from water surf aces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. The estimated volatilization half-life from a model pond is 16 months if adsorption is considered(4). According to a classification scheme(5), BC F values of 18,197 in fathead minnows(6) and 8,974 in rainbow trout (7), suggest that bioconcentration in aquatic organisms is very high, provided the compound is not metabolized by the organism (SRC). A half-life of 210 days in sediment(2 ) indicates that biodegradation is not an important environmental fate process in w ater (SRC). [(1) Swann RL et al; Res Rev 85: 17-28 (1983) (2) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246- 148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009. (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-9, 15-1 to 15-29 (1990) (4) US EPA; EXAMS II Computer Simulation (1987) (6) Franke C et al; Chemosphere 29: 1501- 14 (1994) (6) Veith GD, Kosian P; pp. 269-81 in Physical Behavior of PCBs in the Great Lakes. Mackay D et al, eds., Ann Arbor, MI: Ann Arbor Sci (1983) (7) Hardy ML; Environ Toxicol Chem 23: 656-61 (2004)]
**PEER REVIEWED**

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of se mivolatile organic compounds in the atmosphere (1), hexabromocyclododecance, which has a vapor pressure of 4.72X 10-6 mm Hg at 25 deg C(2), will exist in both the vapor and
p articulate phases in the ambient atmosphere. Vapo r -phase hexabromocyclododecance is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals( SRC); the half-life for this reaction in air is estimated to be 3 days(SRC), calculated from its rate constant of 6.1X10- 12 cu cm/molecule-sec at 25 deg C(SRC) that was derived using a structure estimatio n method(3). Particulate-phase hexabromocyclododecance may be removed from the air by wet or dry deposition(SRC). Hexabromocyclododecance does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC). [(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988) (2) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009. (3) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993) (4) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 8-12 (1990)] **PEER REVIEWED**

Environmental Biodegradation: AEROBIC: Hexabromocyclododecane at a concentration of 7.7 mg/L is considered to be not readily biodegradable in the OECD 301D screening test(1). In a soil dissipation study, a hal f-life of 63 days at 20 deg C was reported for gammahexabromocyclododecane , using sandy loam soil amended with sewage sludge ; no dissipation was reported using an abiotic soil (1). Another aerobic soil dissipation study reported no loss of 14C- hexabromocyclododecane in 112 days at a test chemical concentration of 3.0 mg/kg dry weight(1). [(1) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009.] **PEER
REVIEWED**

Environmental Abiotic Degradation: The rate constant for the vapor-phase reaction of hexabrom ocyclododecance with photochemically-produced hydroxyl radicals has been estimated as 6.1X10-12 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimation met hod(1). This corresponds to an atmospheric half-life of about three days at an atmosphe ric concentration of 5X10+5 hydr oxyl radicals per cu cm(1). Hexabromocyclododecance is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). Hexabromocycl ododecance does not contain chromophores that absorb at wavelengths >290 nm(2) and therefore is not expected to be sus ceptible to direct photolysis by s unlight(SRC). Half-lives in air of 3 days and in water of 2-25 days gives potential for long-range transport(3). [(1) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993) (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5, 8-12 (1990) (3) Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED**

Environmental Bioconcentration: Hexabromocyclododecane can bioaccumulate in fatty tissues(1). A BCF of 18,197 was reported in fathead minnows(2) and 8,974 in rainbow trout(3) for hexabromocyclododecance. According to a cl assification scheme(4), these BCF values suggest the potentia l for bioconcentration in aquatic organism s is very high(SRC), provided the compound is not metabolized by the organism(SRC). [(1) Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008) (2) Veith GD, Kosian P; pp. 269- 

### Pa g e 3 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search81 in Physical Behavior of PCBs in the Great Lakes. Mackay D et al, eds., Ann Arbor, MI: Ann Arbor Sci (1983) (3) Hardy ML; Environ Toxicol Chem 23: 656-61 (2004) (4) Franke C et al; Chemosphere 29: 1501-14 (1994)] **PEER REVIEWED**

Soil Adsorption/Mobility: The Koc of hexabromocyclododecane is estimated as 27,000(SRC), using a log Kow of 5.63(1) and a regression-derived equation(2). According to a classification scheme (3), this estimated Koc value suggests that hexabromocyclododecane is expected to be immobile in soil. The compound has a low water so lubility and therefore an affinity for particles and sediments( 4). [(1) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009. (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-9 (1990) (3) Swann RL et al; Res Rev 85: 17-28 (1983) (4) de Wit CA; Chemosphere 46: 583-624 (2002)] **PEER
REVIEWED**

Volatilization from Water/Soil: The Henry's Law constant for hexabromocyclododecane is estimated as 6.1X10-4 atm-cu m/mole(SRC) derived from its vapor
p ressure, 4.72X10-6 mm Hg(1), and water solubility, 6.56X10- 3 mg/L(1). This Henry's Law constant indicates that hexabromocyclododecane is expected to volatilize from water surfaces(2). Ba sed on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/s ec)(2) is estimated as 11 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 11 day s (SRC). However, volatilization from water su rfaces is expected to be attenuated by adso rption to suspended solids and sediment in the water column. The estimated volatili zation half-life from a model pond is 16 m onths if adsorption is considered(3). Hexabromocyclododecane 's estimated Henry's Law constant indicates that volatilization fr om moist soil surfaces may occur (SRC). Hexabromocyclododecane is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1). [(1) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009. (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15- 29 (1990) (3) US EPA; EXAMS II Computer Simulation (1987)] **PEER REVIEWED**

Sediment/Soil Concentrations: SEDIMENT: Hexabromocyclododecance concentrations ranged from not detected (detection limit in the range of 6-50 pg/g dry weight) to 514 ng/g dry weight in sediments from the Cinca River (tributary to the Ebro River, Spain) collected in the vicinity of the heavily industrialized area of Monzon(1). Sediment samples from the Swedish River Viskin, sampled in 1995 and collected up and downstream from textile industries, contained hexabromocyclododecane at concentrations ranging from <0.9 ng/g (upstream) to 7,000 ng/g (downstream)(2). A con centration of <1.0 ng/g was detected in sediment from Lake Skaresjon, a parallel water system(2). A concentration of <1.0 ng/g was detected in se diment from Lake Skaresjon, a pa rallel water system(2). Three dated sediment cores from a prealpine lake , Lake Thun, in Switzerland revealed that hexabromocyclododecane concentrations started to increase in the 1980s through the 1990s with a decrease observed in one core more recently(3). [(1) Eljarrat E et al; Environ Sci Technol 38: 2603-8 (2004) (2) Sellstrom U et al; Environ Toxicol Chem 17: 1065-72 (1998) (3) Bogdal C et al; Environ Sci Technol 42: 6817-22 (2008)] **PEER REVIEWED**

Fish/Seafood Concentrations: Hexabromocyclododecance concentrations ranged from not detected (detection limit in the range of 2-19 pg/g wet weight) to 1,172 ng/g wet weight in 23 fish samples (Barbus graellsi) from the Cinca River (tributary to the Eb ro River, Spain) collected in the vicinity of the heavily industrialized area of Monzon(1). Fi sh samples from the Swedish River Viskin, sampled in 1995 and collected up and downstream from textile industries, contained hexabromocyclododecane at concentrations ranging from <80 ng/g lipid weight (upstream) to 8,000 ng/g lipid weight (downstream)(2). A concentration of <90 ng/g lipid weight was detected in fish from Lake Skaresjon, a parallel water system(2). Upon anal ysis of the Lake Ontario pelagic food web, it was found that concentrations of the alpha-isomer were higher than the gamma-isomer, with beta- hexabromocyclododecane being below the detection limit of 30 pg/g wet weight(3). Mean alpha-isomer level in plankt on was 0.03 ng/g wet weight; mean gamma-isomer level in Mysis was 0.01 ng/g wet weight(3). Levels in forage fish were 0.005 and 0.05 (alewife); 0.05 and 0.4 (sculpin); 0.07 a nd 0.25 (smelt); levels in a top predator were 1.5 and 0.4 ng/g wet weight (lake trout) for alpha- a nd gamma-isomers, respectively (3). [(1) Eljarrat E et al; Environ Sci Technol 38: 2603-8 (2004) (2) Sellstrom U et al; Environ Toxicol Chem 17: 1065-72 (1998) (3) Tomy GT et al; Environ Sci Technol 38: 2298-303 (2004)] **PEER REVIEWED**

Hexabromocyclododecane concentrations in various fish(1). Species Location alpha- (ng/g) gamma- (ng/g) Total (ng/g)
Rainbow trout Lake Ontario 0.4-3.8 wet weight 0.1-0.8 wet weight 0.5-4.6 wet weight
Whitefish Swiss lakes 54-310 lipid weight <15 lipid weight 25-210 lipid weight 

### Pa g e 4 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search[(1) Janek K et al; Environ Sci Technol 39: 1987-94 (2005)] **PEER REVIEWED** PubMed Abstract

Concentrations of tetrabromobisphenol A (TBBPA) and alpha-, beta-, and gamma-isomers of hexabromocyclododecanes (HBCDs) were determined by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) in .. marine top-level
p redators ... bull shark, and Atlantic sharpnose shar k --collected from coastal waters of Florida, USA. The overall mean concentrations (mean+/-SD) of TBBPA a nd HBCDs were ... 9.5+/-12 and 77.7+/-128 ng/ g lipid wt in bull shark muscle, and 0.872+/-0.5 and 54.5+/-88 ng/g lipid wt in Atlantic sharpnose shark muscle. Overall mean concentrations of HBCDs were 5-10- fold higher than mean TBBPA concentrations, in all of the sa mples analyzed. The highest con centrations of TBBPA and HBCDs were detected in the bull shark muscle at con centrations of 35.6 and 413 ng/ g, lipid wt, respectively. [Johnson-Restrepo B et al; Chemosphere 70(11): 1935-44 (2008).] **PEER REVIEWED** PubMed Abstract

Animal Concentrations: Hexabromocyclododecane concentrations in two of 40 eggs of Little Owls (Athene noctua) in Belgium were 20 and 50 ng/g lipid (1). Concentrations found in eggs of Peregrine Falcons (Falco peregrinus) breeding in Sweden were 150 and 250 ng/g lipid weight for northern and southern wild populations, re spectively; it was not detected in eggs of captive falcons(2). Levels in Guillemo t eggs (Uria algae) from the Baltic Sea were sampled betw een 1969 and 2001(3). Beginning with 1969 at 78 ng/g lipid weight, concentrations peaked in the mid-1970s at 150 ng/g lipid weight ) followed by a decrease (34 ng/g lipid weight in 1981), and the n increased in the late-1980s to 130 ng/g lipid weight, remaining stable at a higher level thereafter, 110-170 ng/g lipid weight( 3). [(1) Jaspers V et al; Environ Pollut 136: 81-88 (2005) (2) Lindberg P et al; Environ Sci Technol 38: 93- 96 (2004) (3) Sellstrom U et al; Environ Sci Technol 37: 5496-501 (2003)] **PEER REVIEWED**

Hexabromocyclododecane in 43 unhatched bird eggs of 8 South African species, sampled from November 2004 to March 2005 (1).

[(1) Polder A et al; Chemosphere 73: 148-54 (2008)] **PEER REVIEWED** PubMed Abstract

Hexabromocycldodecane concentrations in the Norweg ian North-East Atlantic Marine Ecosystem(1). Whitefish Lake Winnipeg 1.7 wet weight 1.3 wet weight 3 wet weight
Fish Lake Winnipeg 92 lipid weight
Barbel Cinca River, Spain not detected to 1,172 wet weight

Trout River Skerne, UK 20-26 wet weight Herring Baltic Sea 34-180 lipid weight Herring North Sea 21-58 lipid weight
Baltic salmon Baltic Sea 51 lipid weight Eel, cod, hake The Netherlands <0.6-93 lipid weight

Seastar Western Scheldt <30-84 lipid weight
Marine fish Western Scheldt 6.6-1,096 lipid weight <1-51 lipid weight 9-1,110 lipid weight

Common Name Scientific Name Habitat Concentration (ng/g lipid weight; detection limit = 0.2 ng/g) Location (South Africa)
African darter Anhinga rufa Aquatic 3.0 Parys

Reed cormorant Phalacrocorax africanus Aquatic <detection limit Parys

Cattle egret Bubulcus ibis Mainly terrestrial <detection limit Barberspan; Parys
African sacred ibis Threskiornis aethiopicus Aquatic/terrestrial 4.8 and 7.1 Parys

Crowned plover Vanellus coronsatus Aquatic/terrestrial 1.6 Koppies

Little grebe Tachybaptus ruficollis Aquatic <detection limit Koppies

White-fronted plover Charadrius marginatus Aquatic/marine <detection limit Velddrif

Kelp gull Larus dominicanus Aquatic/marine <detection limit Velddrif

Location Species Concentration (ng/g lipid weight) Oslofjord Calanus (sp) 4.01 Oslofjord Atlantic cod 25.6 

### Pa g e 5 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search[(1) Jenssen BM et al; Environ Health Perspect 115: 35-41 (2007)] **PEER REVIEWED**

Hexabromocyclododecane concentrations in blubber of marine mammals from the UK(1).

[(1) Law RJ et al; Chemosphere 73: 223-41 (2008)] **PEER REVIEWED** PubMed Abstract

Hexabromocyclododecane concentrations in blubber of marine mammals from Japan(1). Oslofjord Harbor seal 50.5 Oslofjord Common tern 36.5

Froan Calanus finmarchicus not detected

Froan Atlantic cod 18.7

Froan Harbor seal 22.3

Froan Artic tern 17.0
Bear Island Polar cod 11.7 Spitsbergen Calanus glacialis not detected Spitsbergen Polar cod 1.80 Spitsbergen Harbor seal 3.66 Spitsbergen Ringed seal 19.6 Spitsbergen Arctic tern 4.62

Species Location Date Mean Concentration (ug/kg wet weight) Mean Concentration (ug/kg lipid weight) Sowerby's beaked whale Rosemarkie, Highland 04/08/2004 39 44

Newport, Pembrokeshire 28/09/2004 11 13

Risso's dolphin Aberdeen, Grampian 01/11/2004 34 55 Dornoch Highland 19/11/2004 39 71 Lossiemouth, Grampian 02/09/2005 110 207 Bottlenose dolphin Gwithian, Cornwall 21/12/2004 170 218 Penzance, Cornwall 11/08/2005 270 871 Skinburness, Cumbria 12/12/2006 1,230 1,540 Long-finned pilot whale Treginnis, Pembrokeshire 06/06/2005 45 58

White-beaked dolphin Bay of Tuqouy, Orkney 02/12/2005 558 664

Minke whale Flotta, Orkney 11/12/2005 17 24
Northern bottlenose whale Battersea, London 21/01/2006 21 23

Skegness Lincolnshire 31/08/2006 33; 35 38; 41 Common dolphin Bournemouth, Dorset 09/03/2006 134 189 White-sided dolphin Crovie, Grampian 21/03/2006 51 61

Striped dolphin Whitely Bay, Tyne and Wear 16/04/2006 25 28

Species Location Year Mean Concentration (ug/kg lipid weight)
Northern Fur Seal Off Sanriku, Japan 1972 <0.1

1976 0.69-5.1

1980 0.56-0.99

1982 0.84-16

1985 0.46-2.7

1988 2.3-5.0 

### Pa g e 6 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search[(1) Law RJ et al; Chemosphere 73: 223-41 (2008)] **PEER REVIEWED** PubMed Abstract

... The total-HBCDD levels in blubber of female harbor porpoises (Phocoena phocoena) and common dolphins (Delphinus delphis) stranded on Western European coasts between Scotland (U K) and Galicia in Spain /were investigated/ by GC/MS. The isomeric composition of HBCDD in blubber was investigated by LC/MS in a selection of 19 samples, representing all sampling areas. The possible influence of cytochrome P450 mediated biotransformation on the ch anges in the isomer composition (alpha-, beta- and gamma- HBCD ) in the residues in blubber with respect to the commer cial mixture was investigated by in vitro assays with hepatic microsomes of rat and harbor seal (Phoca vituli na). All the 19 samples (10 harbor porpoises and 9 common dolphins) contained exclusively the alpha-diastereomer, despite the dominan ce of the gamma-diastereomer in commercial mixtures. In the four replicate preparations of (phenobarbit al induced) rat microsomes and an artifici al 1:1:1 mixture of the three diastereomer s, the
p eaks of the beta- and gamma-diastereomers of HBCDD showeda highly significant decrease, but the peak of the alphadiastereomer had not become significantly smaller even after 90 minutes incubation at 37 deg C. In the 90-minutes incubation wi th harbor seal microsomes, the beta- and ga mma-diastereomer seemed to decrease, wh ereas no significant disappearance of alphaHBCDD was observed. For beta- HBCD , three bromine-containing metabolites coul d be observed, while for gamma-HBCDD two such metabolites were observed. Hydroxy- metabolites of both the beta-diastereomer and gamma-diastereomer were found. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.385 (May 2008). Available from, as of February 25, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Concentrations of tetrabromobisphenol A (TBBPA) and alpha-, beta-, and gamma-isomers of hexabromocyclododecanes (HBCDs) were determined by liquid chromatography-tandem ma ss spectrometry (LC-ESI-MS/MS) in... /a/ marine top-level
p redato r --bottlenose dolphin--collected from coasta l waters of Florida, USA. The overall mean concentrations (mean+/-SD) of TBBPA and HBCDs were 1.2+/-3 and 7.38+/-18 ng/g lipid wt in bottlenose dolphin blubb er. Overall mean concentrations of HBCDs were 5-10-fold higher than mean TBBPA con centrations, in all of the samples analyzed. ... HBCD concentrations in bottlenose dolphins from the United States were 1-2 orders of magnitude lower than the concentrations reported for other cetace an species from Europe. [Johnson-Restrepo B et al; Chemosphere 70(11): 1935-44 (2008).] **PEER REVIEWED** PubMed Abstract

Milk Concentrations: ENVIRONMENTAL: Hexabromocyclododecane levels in mothers' milk from the Stockholm, Sweden area increased from 0.13
p mol/g lipid in 1980 to 0.60 pmol/g lipid in 2004, with the hi ghest levels reported in 2001 and 2002, 0.83 and 0.93 pmol/g lipid

, respectively. Levels in Norwegian breast milk samples ranged from 0.25-2 ng/g lipids over a study period of 1986-2001(1). [(1) ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available at http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf as of Feb 23, 2009.] **PEER
REVIEWED**

ENVIRONMENTAL: The National Food Administ ration in Sweden has analyzed HBCDD a nd other substances in mother's milk from Swedish women in two different studies . The first study detected HBCDD in 12 of 33 samples. The samples were taken from
p rimiparous, age 19-40, living in Uppsala Count y, Sweden, two weeks after delivery. The limit of detection was /leas than/ 15 pg HBCDD/g mothers milk (fresh weight). On a lipid weight basis, the mean and max concentrations were 0.45 and 2.4 ng/g fat, respectively. [European Chemicals Bureau; European Union Risk Assessment Report, hexabromocycleododecane, (25637-99-4) (2008). Available from, as of February 25, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

ENVIRONMENTAL: Hexabromocyclododecane ( HBCD ) is a type of brominated flame retardant. We investigated the time trend of the stereoisomer-s pecific concentrations of HBCD (alpha, beta, and gamma) in breast milk samples of Japanese women by using liquid chromatography-tandem mass spectrometry (LC/MS /MS). The pooled milk lipid samples collected in 1973, 1978, 1983, 1988, 1993, 1999, and from 2000 to 2006 were analysed. The concentration was below the detection limit in the samples collected between 1973 and 1983 and increased in t hose collected since 1988. Between 1988 and 2006, alpha- HBCD was detected in all 11 breast milk samples collected from 25 to 29-year-old Japanese women; gamma- HBCD , in 7; and beta- HBCD , in none of the samples. Time trend of summation operatorHBCD ap peared to be related to that of the industrial HBCD consumption level in Japan. 1991 10-19

1994 21-55

1997 13-67

1998 12-32
Melon-headed whale Pacific Coast, Japan 1982 2.7-9.7

2001 330-460 Finless porpoise South China 1990 4.7-37
2000/2001 21-55 

### Pa g e 7 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search[Kakimoto K et al; Chemosphere 71(6): 110-4 (2008).] **PEER REVIEWED** PubMed Abstract

Other Environmental Concentrations: Hexabromocyclododecane concentrations in 19 house dust samples from th e greater Boston, MA area in the Fall, 2006 ranged from <4.5 ng/g to a maximum of 130,200 ng/g with a median value of 30 ng/g(1). The geometric m ean concentrations were 354,144, and 282 ng/g for the main living area, bedroom, and home vacuum bag, respectively(1). Total (alpha-, beta-, and gammaisomers) hexabromocyclododecane median concentrations in house dust were 730 ng/g, 390 ng/g, and 640 ng/g in samples from Birmingham, UK (31 samples), Amarillo, TX (13 samples), and Toronto, Canada (8 samples), respectively(2). Sampling was conducted in July-Augist 2006 in the UK, October 2006 in TX, and September 2006 in Canada(2). Mean levels in dust collected from six tv sets in Japan were 2.8 ug/g; circuit board - < 0.3 ug/g; front cabinets - 0.38 ug/g; rear cabinet - 2.2 ng/g(3). [(1) Stapleton HM et al; Environ Sci Technol 42: 6910-6 (2008) (2) Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008) (3) Takigami H et al; Chemosphere 73: 161-9 (2008)] **PEER REVIEWED**

Hexabromocyclododecane concentrations in commercially available textiles in Japan ranged from 22,000 to 43,000 mg/kg, about 2.2-4.3%, with a higher proportion of the alpha-diastereoisomer(1). [(1) Kajiwara N et al; Chemosphere 74: 1485-9 (2009)] **PEER REVIEWED** PubMed Abstract



### Chemical/Physical Properties:

Molecular Formula: C12-H18-Br6 [National Library of Medicine, SIS; ChemIDplus Lite Record for Hexabromocyclododecane (25637-99-4). Available from, as of February 23, 2009: http://chem.sis.nlm.nih.gov/chemidplus/chemidlite.jsp **PEER
REVIEWED**

Molecular Weight: 641.7 [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Color/Form: White solid [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Odor: Odorless [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Boiling Point: Decomposes >190 deg C [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Melting Point: Range 172-184 to 201-205 deg C; 190 deg C avg [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Octanol/Water Partition Coefficient: log Kow = 5.63 [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) 

### Pa g e 8 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/searchand all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Solubilities: In water, 6.56X10-3 mg/L at 21 deg C [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Vapor Pressure: 4.72X10-6 mm Hg at 21 deg C [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Other Chemical/Physical Properties: It has a complex stereochemistry, comprising a theoretical 16 ster ioisomers, including 6 diastereom eric pairs of enantiomers, a nd 4 meso forms. The commercial formulations consist mainly of the alpha, beta, and gamma diasteriomers ... with gamma
p redominant. [Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED** PubMed Abstract

Henry's Law constant = 6.08X10-4 atm-cu m/mol at 25 deg C (est) [SRC; The Physical Properties Database (PHYSPROP). Syracuse, NY: Syracuse Res Corp. Available from, as of Feb 24, 2009: http://www.syrres.com/esc/physprop.htm **PEER REVIEWED**

Hydroxyl radical reaction rate constant = 6.12X10-12 cu cm/molec sec at 25 deg C (est) [US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.0. Jan, 2009. Available from, as of Feb 18, 2009: http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm **PEER REVIEWED**



### Manufacturing/Use Information:

Major Uses: Widely used brominated flame retardant [ECHA; European Chemicals Agency. SHVC Support Document. Substance name: Hexabromocyclododecane (HBCDD) and all major diastereoisomers identified. EC number: 246-148-4 and 221-605-9. Available from, as of Feb 23, 2009: http://echa.europa.eu/doc/candidate_list/svhc_supdoc_hbccd_publication.pdf **PEER REVIEWED**

Additive to expanded and extruded polystyrene foams for thermal in sulation of buildings ... to a lesser extent to high-impact
p olystyrene used in enclosures for elect ronic equipment, such as televisions. [Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED** PubMed Abstract

...The use of HBCDD in polypropylene (PP), adhesives, latex binde rs and unsaturated polyester has been reported in the USA. ...The use of HBCDD in polypropylene (PP) is confirmed. HBCDD can be used in adhesives and coatings and in SAN resins (styrene-acrylonitrile copolymer). It may also be used in PVC (wires, cables and textile coatings). [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.51 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

HBCDD is used in several products, some of which are availa ble to consumers. Some examples of end-products containing HBCDD are: flat and pile upholst ered furniture, upholstery seatings in transporta tion, draperies, and wall coverings, bed mattr ess ticking, interior textiles, automobile in terior textiles, car cushions, insulation boards of transport vehicles, insulation boa rds in building constructions, parking decks, insulation boards agains t frost heaves of road and railway embankments, packaging material, electrical and electronic equipmen t, video cassette housings, polyvinyl chlori de wire, cable and textile coating, pro tecting
p aints for military purposes. [European Chemicals Bureau; European Union Risk Assessment Report, hexabromocycleododecane, (25637-99-4) (2008). Available from, as of February 25, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Manufacturers: Albermarle Corporation, 451 Florida St., Baton Rouge, LA 70801, (225) 388-8011; Production site: Magnolia, AR 71753 [SRI Consulting. 2008 Directory of Chemical Producers United States. Menlo Park, CA 2008, p. 627] **PEER
REVIEWED** 

### Pa g e 9 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/searchChemtura Corporation, 199 Benson Rd., Middlebury, CT 06762, (203) 573-2000; Production site: El Dorado, AR 71730 [SRI Consulting. 2008 Directory of Chemical Producers United States. Menlo Park, CA 2008, p. 627] **PEER
REVIEWED**

Methods of Manufacturing: An aliphatic, brominated cyclic alkane produced by bromination of cyclododecatri-1,5,9-ene [Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED** PubMed Abstract

Technical grade HBCDD is generally produced from cis, trans, trans-1,5,9-cyclododecatriene (CDT), one of four CDT isomers, (CAS No. 27070-59-3). The reaction, trans-addition of bromine to the double bonds of CDT, results in the three diastereomers alpha-, beta- and gamma- HBCDD. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.28 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

General Manufacturing Information: May be used as an alternative to the banned PBDE formulations [Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED** PubMed Abstract

Formulations/Preparations: The final distribution of the diastereomer s in technical HBCDD varies with a range of about 70-95% gamma-HBCDD and 5-30 % alpha- and beta-HBCDD. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.28 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Technical HBCDD is manufactured in two forms, high-melting (HM) and low-melti ng (LM). The low-melting HBCDD consists of 70-80% gamma-, 20-30% of alpha- and beta-HBCDD. The high- melting HBCDD consists of 90% or more of gamma-HBCDD. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.32 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

According to Material Safety Data Sheets from Great Lakes /C hemical Corporation/ there ar e three technical products of hexabromocyclododecane . One product is 100% pure, another product contains an inorganic stabilizer, and a third product contains 40-60% HBCDD, water and a component A. The Dead Sea Bromine Group has two technical products, one which is 99.5% pure and another which is heat stabilized grade. Albema rle also has two technical products, one of high-purity grade available in powder or granular form, the other one of high-purity grade is ground to a fine particle size. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.32 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Impurities: ...The impurities in HBCDD are less than 4% w/w. The stated impurities are tetr abromocyclododecane and other brominated cyclododecanes. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.32 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Consumption Patterns: End products include upholstered furniture, in terior textiles, automobile interior te xtiles, car cushions and insulation blocks in trucks and caravans as well as in building materials such as house walls, cellars, roofs and parking decks, against frost heavi ng in roads and railway embankments, packing material, vide o cassette recorder housi ng and electric equipment. [de Wit CA; Chemosphere 46: 583-624 (2002)] **PEER REVIEWED** PubMed Abstract

(2001) World market demand ... was 16,700 tons of which about 9,500 tons was consumed in Europe. [Abou-Elwafa Abdallah H et al; Environ Sci Technol 42: 459-64 (2008)] **PEER REVIEWED** PubMed Abstract

U. S. Production: Production volumes for non-confidential chemi cals reported under the Inventory Update Rule.

Year Production Range (pounds)

1986 10 thousand - 500 thousand

1990 No Reports

1994 No Reports 

### Pa g e 10 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

6/1/2011 htt p ://toxnet.nlm.nih. g ov/c g i- b in/sis/search[US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclododecane, hexabromo- (25637-99-4). Available from, as of February 18, 2009: http://www.epa.gov/oppt/iur/tools/data/2002

- vol.html **PEER REVIEWED**

Moderate production volume (MPV) [US EPA; Risk-Based Prioritization Document. Initial Risk-Based Prioritization of High Production Volume Chemicals. Chemical Category: Hexabromocyclododecane (HBCD). CAS 3194-55-6 1,2,5,6,9,10- hexabromocyclododecane; CAS 25637-99-4 hexabromocyclododecane. 3/18/2008.] **PEER REVIEWED**



### Synonyms and Identifiers:

Related HSDB Records: 6110 [1,2,5,6,9,10

- HEXABROMOCYCLODODECANE ] (mixture component)

Synonyms: Pyrogard SR-103

**PEER REVIEWED**

HBCDD
**PEER REVIEWED**

Formulations/Preparations: The final distribution of the diastereomer s in technical HBCDD varies with a range of about 70-95% gamma-HBCDD and 5-30 % alpha- and beta-HBCDD. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.28 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Technical HBCDD is manufactured in two forms, high-melting (HM) and low-melti ng (LM). The low-melting HBCDD consists of 70-80% gamma-, 20-30% of alpha- and beta-HBCDD. The high- melting HBCDD consists of 90% or more of gamma-HBCDD. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.32 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

According to Material Safety Data Sheets from Great Lakes /C hemical Corporation/ there ar e three technical products of hexabromocyclododecane . One product is 100% pure, another product contains an inorganic stabilizer, and a third product contains 40-60% HBCDD, water and a component A. The Dead Sea Bromine Group has two technical products, one which is 99.5% pure and another which is heat stabilized grade. Albema rle also has two technical products, one of high-purity grade available in powder or granular form, the other one of high-purity grade is ground to a fine particle size. [European Commission, ESIS; Risk Assessment: Hexabromocyclododecane (25637-99-4) p.32 (May 2008). Available from, as of February 26, 2009: http://ecb.jrc.ec.europa.eu/esis/ **PEER REVIEWED**

Hazardous Substances Databank Number: 7695

Last Review Date: Reviewed b y SRP on 5/7/2009 1998 10 thousand - 500 thousand

2002 10 thousand - 500 thousand 

### Pa g e 11 of 11 HEXABROMOCYCLODODECANE - National Librar y of Medicine HSDB Database

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