Maternal plasma concentrations of polybrominated diphenyl ether (PBDE) and infant birth weight

Abstract

Background Exposure to brominated flame retardants is an emerging area of health concern with epidemiological studies reporting neurobehavioural and neurotoxic effects. To date, a small number of studies have investigated the association between PBDE concentrations and birth outcomes although findings have been inconsistent. The mechanisms by which PBDEs may affect birth outcomes are unknown, however PBDEs influence on thyroid hormone homeostasis may be involved. Aims The aim of this study was to assess exposure to PBDEs among pregnant women in Western Australia. The association with infant birth weight was also investigated. Methods Pregnant women, aged 18 years or older, non-smokers, not occupationally exposed to persistent organic pollutants and living in Western Australia (n=173) were recruited between 2008 and 2011 to the Australian Maternal Exposure to Toxic Substances (AMETS) study. Participants completed a questionnaire on demographic and lifestyle information as well as activities that may increase exposure to PBDEs. Birth weight was collected by a follow up questionnaire. At 38 weeks gestation, participants provided a plasma sample and these were analysed for concentrations of BDE-47, -99, -100, -153 and -154. STATA12 was used for the statistical analysis. The relationship between birth weight and maternal PBDE concentrations was investigated using logistic regression. Results Mean age of respondents was 32 years and for 48.5% of women this was their first pregnancy. The concentrations of S5PBDE ranged from 13.2 to 1389.6 pg/g ww with a median of 54.3 pg/g ww. Adjusting for a range of potential confounders a unit increase in lnBDE-47 reduced birth weight by 73.3 grams (95%CI -141.62, -4.95) and 78.8 for lnBDE-100 (95%CI -147.49, -10.43). However, confidence intervals are wide and the adjusted R2s are small (0.21 for both). Conclusions Maternal concentrations of BDE-47 and -100 may reduce infant birth weight. This should be investigated further in a larger study.