Hexabromocyclododecanes in human adipose tissue from Japan

Contamination by hexabromocyclododecanes (HBCDs), a group of brominated flame retardants, is of great concern due to their bioaccumulative nature and toxic implications. HBCD consumption in Japan is the highest among Asian countries and is still growing. In this regard, human exposure to HBCDs is of great concern in Japan. We present here the results of our investigation on Japanese human adipose tissue using LC-MS/MS. HBCDs were detected in all the samples analysed, and were generally higher in men than in women. Abstract. Residue levels of hexabromocyclododecanes (HBCDs) were measured using LC-MS/MS in the Japanese human adipose tissue samples collected during 20032004 from Ehime prefecture (n ≤ 26) and Kanto region (n ≤ 9) of Japan. Concentrations of HBCDs (0.8539 ng g^-1 lipid) in the adipose tissue samples were 12 orders of magnitude lower than those of organochlorines (OCs). Regional differences between HBCD levels in Ehime prefecture and Kanto region were not significant. No age-dependent accumulation of HBCDs was observed. HBCD levels in men were significantly higher than those in women. Significant positive correlation between polybrominated diphenyl ethers (PBDEs) and HBCDs implies similar routes of exposure to these contaminants for Japanese citizens. -HBCD was predominant among the three isomers, which is consistent with the other reports on bioaccumulation of -HBCD in higher trophic animals.