Mercury speciation and mercury-binding protein study by HPLC-ICP-MS on the estimation of mercury toxicity between maternal and infant rats

A comparative study of methylmercury (MeHg) metabolism and its conversion into inorganic mercury (I-Hg) in organic tissues (brain, liver and kidney) and the subcellular fractions (nucleus, mitochondrion, lysosome, microsome and cytosol) of maternal and infant rats after infant in utero and lactational exposure to methylmercury was achieved by extraction preconcentration with HPLC-ICP-MS determination. The quantification of Hg-containing proteins in brain cytosol was studied by HPLC hyphenated on-line isotope dilution ICP-MS and the proteins were analyzed by SDS-PAGE and MALDI-TOF-MS. The results demonstrated that the methods could be successfully used in the study of mercury species in sub-compartments of organ cells. The study showed that the distribution patterns of MeHg and I-Hg in the levels of organs, the subcellular fractions of organs and proteins are all significantly different between mothers and their offspring, indicating their significantly different metabolism, transportation and accumulation behavior of mercury species, which may be all involved in the toxic mechanism of mercury for adults and young children.