Distribution Kinetics of Dietary Methylmercury in the Arctic Charr (Salvelinus alpinus)

Abstract

We fed immature 1+ arctic charr with a single dose of methyl[203Hg]mercury (MeHg) and quantified distribution kinetics with a new and simple three-compartment caternary model having well-perfused viscera and blood as the central compartment (VB), whereas gut (G) and the rest of body (R) constituted the peripheral compartments. The model accurately described distribution kinetics of MeHg in the fish, using either data of MeHg content in compartments or blood concentration data. Despite the known fast translocation of MeHg between binding sites at the molecular level, its translocation rate between compartments was surprisingly slow, 27 days being needed to complete 95% of the transfer from gut to blood and 48 days for the subsequent transfer to compartment R. This probably results from a limitation of the stepwise transfer rate of MeHg from red blood cells, which contain most of blood MeHg, to plasma and then to tissues due to low plasmatic concentration of small mobile sulfhydryl ligands. The model presented is a convenient tool that could be used to compare the fate of MeHg and other organometals, such as butyltins and alkylleads, in various aquatic and terrestrial animal species.

Methylmercury accumulation, histopathology effects, and cholinesterase activity alterations in medaka (Oryzias latipes) following sublethal exposure to methylmercury chloride

“…The existence of mercury compounds in fish muscle and fat tissues that were usually edible might indicate the potential danger to predators including human beings when natural fish from the polluted areas were preyed. The accumulation pattern of MeHg in medaka tissues was in agreement with the observations in rainbow trout (Oncorhynchus mykiss) (Boudou and Ribeyre, 1985) and Arctic charr (Salvelinus alpinus) (Oliveira Ribeiro et al, 1999) with dietary MeHg poisoning.…”

Quantifying mercury isotope dynamics in captive Pacific bluefin tuna (Thunnus orientalis)

“…MMHg is efficiently solubilized and absorbed in the gastrointestinal tract (Leaner and Mason, 2002). By forming a complex with thiol-ligands, MMHg is readily distributed to all tissues via the bloodstream before reaching the muscle tissue, which is the final storage organ for MMHg in fish (McCloskey et al, 1998;Oliveira Ribeiro et al, 1999). MMHg is also eliminated via the fecal route (Giblin and Massaro, 1973), which most likely occurs during the turnover of muscle tissue given the strong binding affinity of MMHg with thiol-ligands in muscle tissues.…”

Short-term Exposure of Nile Tilapia (Oreochromis niloticus) to Mercury

“…Humans may be exposed to environmental Hg in several ways, e.g., vapor inhalation, accidental direct ingestion, and consumption of Hg-contaminated food, especially fish and seafood (OliveiraRibeiro, Guimaräes, and Pffeiffer 1996;ATSDR 1999;Oliveira-Ribeiro et al 1999). Therefore, humans might get high levels of Hg from bioaccumulation via contaminated food because humans are at the top of the food chain ).…”