Date of Award
Master of Science in Environmental Engineering - (M.S.)
Civil and Environmental Engineering
Richard B. Trattner
Metallothionein (MT) and glutathione (GSH) have been shown in mammalian research to play a role in the sequestration and depuration of mercury. The sulfhydryl groups on both these peptides have a strong affinity for mercury, MT for Hg2+ and GSH for CH3Hg+. In this study, killifish (Fundulus heteroclitus) were force-fed one piece of squid laced with labelled mercuric nitrate to give a final food concentration of 20 ppm 203Hg2+ and 0.03 -0.05 µg g-1 Hg2+ total dose. Most of the mercury, 84.1 ± 12.1% (mean ± standard deviation), is depurated within the first 24 hours; of that retained, most was found in the intestine. There was little change over the next 6 days. The feces contained high amounts of mercury and can be considered the main route of excretion. Thin-layer chromatography of bile showed no noticeable amounts of mercury bound to GSH in the bile. But no conclusions regarding bile and enterohepatic circulation can be made since the killifish is too small a model in which to monitor it. MT was found in appreciable amounts in the liver and intestine homogenates by gel electrophoresis but autoradiography did not demonstrate the binding of Hg2+ to the MT. Most of the mercury which had been retained was associated with both soluble and insoluble proteins of high molecular weight (>90,000 daltons). Therefore the first line of defense for this organism appears to be the intestine, as 90% of the mercury did not get beyond this organ.
Korpanty, Joanne A., "Investigations into rates and mechanisms of mercury depuration in the Killifish, Fundulus Heteroclitus" (1984). Theses. 2185.