| 2406 Inorganic Mercury in Brain in a Fish Eating Population | ||
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L. BJÖRKMAN1, B.F. LUNDEKVAM1, T. LÆGREID1, B.I. BERTELSEN2, I. MORILD2, P. LILLENG2, B. PALM3, M. VAHTER3, and B. LIND3, 1UNIFOB/University of Bergen, Norway, 2Haukeland University Hospital, Bergen, Norway, 3Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden The main sources of mercury (Hg) are methylmercury (MeHg) from the diet (mainly seafood), inorganic mercury (I-Hg) and elemental mercury vapor (Hg0) from dental amalgam restorations. MeHg has a biological half-time of about 70-80 days in the body. The toxicokinetics of mercury released from dental amalgam restorations is not known in detail. Nevertheless, half time values of 58 days in whole body and 21 days in the brain have been used for kinetic calculations of mercury originating from dental amalgam (Clarkson et al 1988). A minor fraction of inorganic Hg may be stored in brain with much longer half-time. Objectives: The aim of this study was to investigate concentrations of MeHg and I-Hg in brain (occipital lobe cortex) in relation to exposure to dental amalgam and age in autopsy cases from a fish eating population without occupational exposure to mercury. Methods: Samples from occipital lobe cortex from 30 deceased individuals were collected in conjunction with autopsies at Haukeland University Hospital, Bergen, Norway. Concentrations of total Hg and I-Hg were determined by cold vapor atomic fluorescence spectrometry at the Karolinska Institute. Results: The median concentrations of MeHg and I-Hg in occipital lobe cortex were 4 and 5 ng/g wet weight, respectively. The case with the highest concentration of I-Hg (a retired dental nurse with 9 times higher concentration than the second highest case) was excluded from the following statistical analyses. The correlation coefficients between number of amalgam surfaces and concentrations of total Hg, MeHg and I-Hg were 0.046 (ns) , -0.14 (ns) and 0.55 (p= .002), respectively (n=29). Conclusion: In a fish eating population, MeHg from the diet may have a marked impact on total mercury concentration in the brain. Discrimination between mercury species is thus necessary to evaluate impact of dental amalgam exposure on Hg concentrations in the brain. | ||
| Seq #255 - Oral Reactions/Syndromes 2:00 PM-4:00 PM, Friday, 11 March 2005 Baltimore Convention Center Exhibit Hall E-F | ||
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