This developmental research project explores relationships among polybrominated diphenyl ether (PBDE) flame retardant concentrations in house dust, PBDE body burdens, and circulating thyroid hormone levels in early childhood. The study is motivated by recent epidemiologic evidence of an association between PBDE serum levels and thyroid disruption in adults, and limited but compelling reports of substantially higher PBDE body burdens in children compared to adults. In a pilot study of 80 children, we seek to establish the feasibility of investigating relationships between PBDE exposure routes, serum concentrations and thyroid function in a larger epidemiologic study, while building the in-house laboratory capacity to measure the range of PBDE congeners in serum and house dust. Serum samples will be obtained from a cohort of 80 children between 2 and 5 years of age who are under general anesthesia for ear tube surgery (myringotomy). Serum will be analyzed for an expanded panel of thyroid markers as well as congener-specific concentrations of PBDEs. In a subset of 20 study participants, house dust will be collected from the main activity room of the home and analyzed for PBDE concentrations. The study aims are to (a) build laboratory capacity to measure congener- specific PBDE concentrations in human serum and house dust (b) characterize the distribution of serum concentrations of PBDEs in a cohort of 80 children between 2 and 5 years, (c) explore associations between serum levels of PBDEs and thyroid hormones in young children, and (d) explore correlations between PBDEs concentrations in house dust and PBDE serum levels in young children to assess dust as a major route of exposure. Collaboration between analytical chemists, epidemiologists, exposure scientists, and pediatric endocrinologists will facilitate investigation of PBDEs from sources in the environment to human body burdens to effects on the endocrine system in a vulnerable and understudied age group. Study findings will contribute to our understanding of the body burden, endocrine effects and exposure routes of brominated flame retardants in early childhood, and will help guide the direction of future research efforts targeting early-life exposures to PBDEs and endocrine disruption.
Polybrominated diphenyl ethers (PBDEs) are flame retardant compounds added to a wide range of consumer products. Despite indications that children have substantially higher exposures to these compounds than adults, little is known about body burdens, exposure pathways and health effects of PBDEs in young children. These questions are investigated in a pilot cohort of 80 children ages 2 to 5 years.