Concentrations of polybrominated diphenyl ethers (PBDEs) and 2,4,6-tribromophenol in human placental tissues

Abstract

Legacy environmental contaminants such as polybrominated diphenyl ethers (PBDEs) are widely detected in human tissues. However, few studies have measured PBDEs in placental tissues, and there are no reported measurements of 2,4,6-tribromophenol (2,4,6-TBP) in placental tissues. Measurements of these contaminants are important for understanding potential fetal exposures, as these compounds have been shown to alter thyroid hormone regulation in vitro and in vivo. In this study, we measured a suite of PBDEs and 2,4,6-TBP in 102 human placental tissues collected between 2010–2011 in Durham County, North Carolina, USA. The most abundant PBDE congener detected was BDE-47, with a mean concentration of 5.09 ng/g lipid (range: 0.12–141 ng/g lipid; detection frequency 91%); however, 2,4,6-TBP was ubiquitously detected and present at higher concentrations with a mean concentration of 15.4 ng/g lipid (range:1.31–316 ng/g lipid; detection frequency 100%). BDE-209 was also detected in more than 50% of the samples, and was significantly associated with 2,4,6-TBP in placental tissues, suggesting they may have a similar source, or that 2,4,6-TBP may be a degradation product of BDE-209. Interestingly, BDE-209 and 2,4,6-TBP were negatively associated with age (rs=−0.16; p=0.10 and rs=−0.17; p=0.08, respectively). The results of this work indicate that PBDEs and 2,4,6-TBP bioaccumulate in human placenta tissue and likely contribute to prenatal exposures to these environmental contaminants. Future studies are needed to determine if these joint exposures are associated with any adverse health measures in infants and children.

Brominated flame retardants in placental tissues: associations with infant sex and thyroid hormone endpoints

“…Because we anticipated that gestational age may be related to TH concentrations in placenta, we further restricted analyses to women giving birth to term infants (37 or more weeks gestation ( n  = 95)). Reflective of the population of women receiving services at the clinic used in recruitment, the HPHB cohort is predominantly African-American with the majority of mothers having a high school diploma or less education and few having private health insurance [23]. All aspects of this study were carried out in accordance with a human subjects research protocol approved by the Duke University Institutional Review Board and all women provided informed consent prior to participation.…”

“…While BFRs have been detected in human placenta samples previously (e.g. [23–25]), the clinical significance of these measures, and their potential importance in thyroid hormone regulation have not, to our knowledge, been evaluated.…”

In vitro cytotoxicity of decabrominated diphenyl ether (PBDE-209) to human red blood cells (hRBCs)

“…In recent years, PBDEs with noticeable concentrations have been observed in environmental media (up to mg/kg dry weight and mg/L levels) (Chen et al, 2012;Newton et al, 2015), animals (up to mg/kg lipid weight and mg/L levels) (Shang et al, 2016;Van den Steen et al, 2007), and human body (such as blood, fat tissue and breast milk, at mg/kg lipid weight level, higher for occupational exposure, tens or even hundreds of the general population) (Herbstman et al, 2010;Leonetti et al, 2016;Nguyen et al, 2016;Shen et al, 2010). The main detected PBDEs homologues are , where their ecological toxicity and potential hazard to human health have attracted widespread attention.…”

Mechanochemical conversion of brominated POPs into useful oxybromides: a greener approach

“…However in the last decade, evidences for toxicity and potential carcinogenicity of brominated organic compounds have been accumulating, as well as for their persistency into the environment234567. These compounds, due to their physicochemical properties and chemical stability, are chiefly used as flame retardants in a large variety of products (e.g.…”