Dietary exposure assessment of Chinese adults and nursing infants to tetrabromobisphenol-A and hexabromocyclododecanes: occurrence measurements in foods and human milk.

Tetrabromobisphenol A(TBBPA) and hexabromocyclododecane diastereoisomers (alpha, beta, and gamma-HBCD) were determined in 24 pooled human milk samples and 48 Chinese total diet study (TDS) samples collected in 2007. On the basis of ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS) analysis, levels of TBBPA ranged from < LOD to 5124 pg/g lipid weight (lw) in human milk and from < LOD to 2044 pg/g lw in TDS samples. The alpha-HBCD diastereoisomer, which ranged from < LOD to 2776 pg/g lw in human milk and from < LOD to 2224 pg/g lw in TDS samples, was generally the most abundant isomer comparing with beta- and gamma-HBCD. The average estimated daily intake (EDI) of TBBPA via human milk for nursing infants with a range 320-37240 pg/kg bodyweight (bw)/day was 5094 pg/kg bw/day, while that of sigmaHBCD was 5837 pg/kg bw/day with a range 670-17320 pg/kg bw/day. The medium bound (< LOD = 1/2LOD) EDI(TBBPA) for a "reference" man via animal origin foods was 256 pg/kg bw/day and EDI(sigmaHBCD) was 432 pg/kg bw/day. Meat and meat products were the main source in the total dietary intake of TBBPA and sigmaHBCD. Our research on the estimated daily intake of TBBPA and sigmaHBCD by the Chinese population indicated large variations in TBBPA and sigmaHBCD levels between provinces. Overall, our data indicate the Chinese EDI was lowerthan the EDI from similar studies in Europe.