Hexabromocyclododecane

Endpoint summary

Description of key information

The following sources of information on observations of health effects in humans are available:
Polder, A., Gabrielsen, G. W., Odland, J. Ø., Savinova, T. N., Tkachev, A., Løken, K. B. and Skaare, J. U. (2008a). Spatial and temporal changes of chlorinated pesticides, PCBs, dioxins (PCDDs/PCDFs) and brominated flame retardants in human breast milk from Northern Russia. Science of the Total Environment (2008) Vol. 391, pp. 41-54.
Polder, A., Thomsen, C., Lindström, G., Løken and Skaare, J. U. (2008b). Levels and temporal trends of chlorinated pestcides, polychlorinated biphenyls and brominated flame retardants in individual human breast milk samples from Northern and Southern Norway. Chemosphere (2008) Vol. 73, pp. 14-23.
Colles, A., Koppen, G., Hanot, V., Nelen, V., Dewolf, M. -C., Noël, E., Malisch, R., Kotz, A., Kypke, K., Biot, P., Vinkx, C. and Schoeters, G. (2008). Fourth WHO-coordinated survey of human milk persistent organic pollutants (POPs): Belgian results. Chemosphere (2008) Vol. 73, pp. 907-914.
Eljarrat, E., Guerra, P., Martínez, E., Farré, M., Alvarez, J. G., López-Teijón, M. and Barceló, D. (2009). Hexabromocyclododecane in Human Breast Milk: Levels and Enantiomeric Patterns. Environ. Sci. Technol. (2009) Vol. 43, pp. 1940-1946.
Kakimoto, K., Akutsu, K., Konishi, Y. and Tanaka, Y. (2008). Time trend of hexabromocyclododecane in breast milk of Japanese women. Chemosphere (2008) Vol. 71, pp. 1110-1114.
Polder et al. (2008a; 2008b) and Colles et al. (2008) were all awarded reliability scores of 2 according to the criteria of Klimisch et al. (1997) based upon the methodologies (based upon WHO test guideline) and the depth of reporting of test methods and results. Eljarrat et al. (2009) and Kakimoto et al. (2008) were both assigned reliability scores of 4 due to insufficient reporting to allow for a reliability assessment.

Additional information

The sample collection phase of the Polder et al. (2008a; 2008b) and Colles et al. (2008) studies were conducted as part of the 3rd WHO-coordinated exposure study and were collected from primapara mothers which had been pre-screened for suitability for the study. Mothers provided informed consent and medical authorities for the sampled countries were involved in order to prevent coercion. The following results were reported from these studies:

Source	Result
Polder et al. (2008a)	Tromsø Mean 0.13
Polder et al. (2008b)	Murmansk (2000) Mean 0.47 ± 0.27 Range 0.20-1.15 Arkangelsk (2002) Mean 0.71 ± 0.38 Range 0.24-1.67
Colles et al. (2008)	Total HBCD 1.5 ng/g lipid base α-isomer 1.5 ng/g lipid base β-isomer <0.8 ng/g lipid base γ-isomer <0.8 ng/g lipid base

Eljarrat et al. (2009) was conducted by analysing samples of breast milk collected 40 days post partum from consenting mothers. Mothers provided consent and the study was conducted in accordance with Spanish regulations and a local ethical committee. Extracted samples were analysed by liquid chromatography for diastereoisomers and by a chiral chromatographic column for enantiometric analysis. The registered substance was detected in 30 out of 33 samples at concentration levels ranging between 3 and 188 ng/g lw, based upon diastereoisomer levels with mean and median concentration of 47 and 27 ng/g lw respectively. Individual isomer levels were shown by enantiomeric analysis, the following results were observed:

Isomer	EF value
α-isomer	0.102-0.204
γ-isomer	0.268-0.602

Kakimoto et al. (2008) investigated the trend of the registered substance in breast milk from 1973 to 2006. Samples were collected days 30-90 postpartum, in all cases informed consent was received from the mother. Samples were pooled per year and stored at 20ºC until clean-up. Samples were extracted and analysed by liquid chromatography-tandem mass spectrometry for levels of the registered substance.The study reported an increase in the concentration of the registered substance in breast milk from 1983 (<0.1 ng/g lw α-isomer, <0.1 ng/g lw β-isomer and <0.2 ng/g lw γ-isomer) to 2006 (1.4 ng/g lw α-isomer, <0.1 ng/g lw β-isomer and <0.2-2.6 ng/g lw γ-isomer), which coincided with increased use of the substance in household articles. Total concentrations of the HBCDD increased from below the limit of detection in 1983 to 1.4-4.0 ng/g lw in 2006.