Polybrominated diphenyl ethers: levels in Townsville sediments, depuration and (anti-)estrogenic effects in Barramundi (Lates calcarifer)

• Main Author: Muirhead, Elisabeth Knowles
• Format: Thesis
• Language: unknown
• Published: 2008
• Subjects: Atlantic salmon
• Online Access: https://researchonline.jcu.edu.au/4778/7/JCU_4778_Muirhead_2008_thesis.pdf

The purpose of this research was to study polybrominated diphenyl ethers (PBDEs) and the effect they have in North Queensland, Australia, specifically in reference to a commercially important fish species, barramundi (Lates calcarifer). This thesis is separated into four main sections: determination of PBDE levels in Ross Creek, Townsville, QLD; toxicokinetics of PBDE-47 in barramundi; optimization of an enzyme-linked immunosorbent assay (ELISA) for detection of vitellogenin (Vtg) in barramundi; and assessing the (anti-)estrogenic effect of PBDE-47 in barramundi. Levels of two common PBDE congeners, PBDE-47 and PBDE-209 were measured in sediments at three sites along Ross Creek in Townsville, QLD. Levels were found to range from below detection (0.2 μg kg-1 dw) to 0.35±0.2 μg kg-1 (dw) for PBDE-47 and from below detection (0.2 μg kg-1 dw) to 0.85±0.07 μg kg-1 (dw) for PBDE-209. Male juvenile barramundi were injected with either a low (1 mg kg-1 bw) or a high (10 mg kg-1 bw) dose of PBDE-47 and then sampled over the course of 14 days in order to determine the depuration rate of PBDE-47 in barramundi. PBDE-47 was found to depurate at a rate of 0.041- 0.069 day-1, a rate which falls well within the range of the literature for depuration of PBDE-47 in fish. An optimal ELISA for the detection of Vtg production in barramundi was determined after comparing the component reagents of a pre-existing ELISA with component reagents developed during this study. Two commercially available Vtg standards, a lipophylised Rainbow Trout Vtg standard (RT Vtg standard) and a lipophylised Atlantic Salmon Vtg standard (Salmon Vtg standard) (both from Caymen Chemical Co), were compared to a purified barramundi Vtg fraction obtained after size exclusion chromatography of plasma from barramundi in which Vtg production was induced by repeated injection of large doses of 17β-estradiol (E2). In addition, a commercially available monoclonal mouse anti-striped bass Vtg primary antibody (ND-3G2, Biosense) was compared with two polyclonal sheep ...