Feasibility study of feces for noninvasive biomonitoring of brominated flame retardants in toddlers
This study investigated the feasibility of using feces as a noninvasive matrix to estimate serum concentrations of brominated flame retardants (BFRs) in toddlers for biomonitoring purposes. Tri- to decabrominated diphenyl ethers (tri-decaBDEs), isomer-specific hexabromocyclododecanes, and 16 emerging BFRs were determined in feces from 22 toddlers (11–15 months of age), and results were compared to previously analyzed matched serum samples. BDE-47, -153, -196, -197, -203, -206, -207, -208, and -209 were detected in the feces creating a matched data set (feces–serum, n = 21). Tetra-octaBDE concentrations were significantly higher (Student’s paired comparisons t test, α = 0.05) in serum versus feces with BDE-153 having the highest mean difference between the sample matrices. BDE-209 was found in significantly higher concentrations in feces compared to serum. Significant correlations (Pearson’s, α = 0.05) between congener-specific concentrations in feces and serum were found for all BDEs except BDE-197 and -203. The feces–serum associations found can be used to estimate serum concentrations of tetra-decaBDEs from feces concentrations and enable a noninvasive sampling method for biomonitoring BDEs in toddlers.
Can washout of known precursors account for the PFAA concentrations measured in precipitation?
Brominated Flame Retardants in Matched Serum Samples from Swedish First-Time Mothers and Their Toddlers
Tri-decabrominated diphenyl ethers and 21 other flame retardants were determined in matched serum samples from 24 Swedish mothers (Uppsala county) and their toddlers (11–15 months of age). The median concentrations of individual polybrominated diphenyl ethers (PBDEs) ranged from 0.036 to 0.95 ng/g lipid in mothers and from 0.057 to 1.5 ng/g lipid in toddlers. BDE-209 was detected in all but one sample. BDE-153 was the predominant congener in the mothers while in toddlers, BDE-209 was found in the highest concentrations. The levels of BDE-47, -100, -207, -208, and -209 in toddlers were significantly higher (p < 0.05) than those in their mothers. Dechlorane Plus (anti- and syn-) and α- and β-tetrabromoethylcyclohexane were detected in a few (2–4) serum samples from both mothers and toddlers. This study also reports concentrations of α-HBCD and eight emerging brominated flame retardants (EBFRs) in the standard reference material serum (SRM 1958, NIST). Lack of correlations between the matched serum samples indicate different exposure routes for octa-decaBDEs in mothers versus toddlers. Congener-to-congener correlations within the mother or toddler cohorts suggest diet as an important exposure pathway for tetra-nonaBDEs for mothers, breastfeeding as a predominant exposure pathway for tetra-hexaBDEs, and dust for octa-decaBDEs for toddlers.