Exposure to polybrominated diphenyls ether (PBDE) and Hypothyroidism in Canadian women

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in a wide range of products, resulting in widespread human exposure. Epidemiological studies in specific populations reported thyroid function alterations induced by exposure to PBDEs, but little epidemiological data are available regarding women from the general population. This study examined the association of PBDEs with hypothyroidism. Cross-sectional analysis of 2007-2009 Canadian Health Measures Survey Participants: 745 women representative of Canadian women ages 30-79 years. The authors estimated the prevalence ratios (PRs) for hypothyroidism in relation to plasma concentrations of BDE-47, 99, 100 and 153 and their sum (?PBDEs). Cases were identified as women who reported a doctor-diagnosed thyroid condition and took thyroid hormone replacement therapy (n=90). Higher levels of BDE-47, 100 and ?PBDEs were associated with an increased prevalence of hypothyroidism. The PR for a 10-fold increase in ?PBDEs was 1.7 (95% CI: 1.0, 3.0). Associations were consistently higher among women aged 30-50 years than among those 51-79 years for ?PBDE and the other PBDE congeners, although the interaction was only significant for BDE-100. For instance, in the younger age group, women with detectable levels of BDE-100 had a PR of 3.8 (95% CI: 1.2, 12.3) compared with women with undetectable levels; the corresponding PR in the older age group was 1.2 (95% CI: 0.6, 2.3). No association was observed for BDE-99 and 153. The authors concluded that plasma PBDE levels were associated with increased prevalence of hypothyroidism in Canadian women ages 30-50 years. Although the cross-sectional design of the study precludes inferences of causality, these findings have important implications given the key role of thyroid hormones in several biological mechanisms during reproductive age.

Authors: Youssef O, Jonathan C, Maryse BF. ;Full Source: Journal of Clinical Endocrinology & Metabolism. 2015 Nov 25: jc20152659. [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][Epub ahead of print] ;[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]