title: Spatial variability in selenium and mercury interactions in a key recreational fish species: implications for human health and environmental monitoring.
abstract: Selenium's (Se) protective effects against mercury (Hg) toxicity have been demonstrated; however, this is seldom considered in health assessments, where dietary exposure is still evaluated by Hg concentration alone. Se:Hg ratios and selenium health benefit values (Se HBVs) offer a more comprehensive seafood safety model. Here we describe total mercury (THg), methylmercury (MeHg) and Se concentrations in fish from a Hg-polluted estuary. Spatial variation in THg, MeHg and Se was evident, though all regions maintained Se:Hg ratio values >1. Se HBV varied between regions and in one region mean negative values (-5.17) were evident. This study provides the first evidence that quoting a single all-encompassing Se HBV is not appropriate when species demonstrate strong site fidelity. It highlights the need for research into Se-Hg relationships in environments with established Hg pollution and reinforces the assertion that Se concentration be considered in assessments of human health risk to Hg exposure.
authors.affiliation: Institute for Marine and Antarctic Studies, University of Tasmania, Private bag 49, Hobart, TAS 7001, Australia. Electronic address: hugh.jones@utas.edu.au.
authors.forename: H J
authors.initials: HJ
authors.lastname: Jones
authors.forename: E C V
authors.initials: EC
authors.lastname: Butler
authors.forename: C K
authors.initials: CK
authors.lastname: Macleod
mesh_terms: D000818:Animals; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D005399:Fishes / Q000378:metabolism*; D006801:Humans; D008628:Mercury / Q000032:analysis* / Q000378:metabolism; D018570:Risk Assessment; D012643:Selenium / Q000032:analysis* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury; D012643:Selenium
keywords: Contaminant assessment; Derwent Estuary; Platycephalus bassensis; Se health benefit value (Se HBV); Seafood safety