Distribution of Polybrominated Diphenyl Ethers (PBDEs) in Newfoundland Diet: Possible Connection to Hypothyroidism

Abstract

Newfoundland sits directly in the Gulf of St. Lawrence and receives drainage from the Great Lakes watershed and the St. Lawrence River, both of which are contaminated with polybrominated diphenyl ethers (PBDEs) from anthropogenic sources. PBDEs have been inversely associated with thyroid hormones, and can also bioaccumulate in species to higher trophic levels. Seafood consumption is consistently found to be one of the main pathways for PBDE exposure in humans. The objective of this study is to explore if there may be a risk of human exposure to PBDEs from local seafood consumption in Newfoundland (NL).Liver samples from turbot (Scophthalmus maximus) and cod (Gadus morhua) were collected off the coasts of NL, and analyzed by gas chromatography/mass spectrometry for PBDE congeners. Residents in Burin (south coast) and New-Wes-Valley (northeast coast) completed a seafood consumption survey and gave blood samples to be tested for thyroid hormone levels ad PBDE concentrations. BDEs-28, 47, 99, 156, 209, and methoxylated polybrominated diphenyl ethers 47 (MeO-BDE-47) and 68 (MeO-BDE-68) were detected in fish liver tissue from all sampling locations around NL. Concentrations of ∑PBDEs (5.52-11.75 ng/g) did not differ in concentration coastwise or by species. Results from the seafood consumption survey and human blood samples will be available for the conference.PBDE concentrations in fish liver do not differ by species or location, therefore there may be PBDEs in the Labrador current and from the St. Lawrence River affecting the marine food chain around NL.This study is the first to document PBDE contamination in the Newfoundland coastal waters and population, and adds to past research on health effects of PBDE contamination from the St. Lawrence River. This research will help inform policy development of chemicals use and regulation in Canada, and increase research into environmental contamination and public health.