Polybrominated Diphenyl Ethers in Human Milk of Croatian First-Time Mothers: 2010 Versus 2020

The presence of selected polybrominated diphenyl ethers (BDE-28, -47, -99, -100, -153, -154, and -183) was investigated in human milk samples collected from first-time mothers living in Zagreb, capital of Croatia. Samples from 2020 and 2010 were analyzed, and the first temporal comparison between the profiles and levels of these compounds in this area was obtained. A statistically significant difference between mass fractions depending on the sampling year was observed only for BDE-99, with values in 2020 higher than in 2010. BDE-153, whose median value (0.25 and 0.26 ng g(-1) lipid weight (l.w.) in 2010 and 2020, respectively) did not decrease in the 10-year period, was the most frequently detected congener in samples from both years. Sigma PBDEs ranged from < LOD to 3.53 ng g(-1) l.w. (median 0.25 ng g(-1) l.w.), and from 0.14 to 6.75 ng g(-1) l.w. (median 0.55 ng g(-1) l.w.) in 2010 and 2020, respectively. Maternal age and reported fish consumption had no effect on observed PBDE mass fractions, while for BDE-153, positive significant correlation (p > 0.05) was observed of its detected mass fraction with mother's body mass index (BMI) before pregnancy and after childbirth. Infants median estimated daily intake (EDI) via milk ingestion for Sigma PBDE was higher in 2020 (3.221 ng kg(-1) bw day(-1)) compared to 2010 (1.429 ng kg(-1) bw day(-1)), but both values were well below threshold value, indicating that human milk consumption in this specific case is unlikely to raise health risks to infants.