Mercury speciation analysis on cell lines of the human central nervous system to explain genotoxic effects

A method for mercury speciation analysis on cell lines of the human central nervous system has been developed in order to study the intracellular mercury uptake and the distribution of mercury species. Glioblastoma (U373) and neuroblastoma (B103) human cell lines were exposed to different levels of monomethylmercury (MMHg). Mercury species were simultaneously extracted with tetramethylammonium hydroxide (TMAH) using a closed-vessel microwave system. The analysis was performed by ethylation and injection into a CGC-pyro-AFS system. An excellent procedural detection limit of 0.008 µM for MMHg was achieved. Recovery studies of cell extracts spiked with MMHg were done to check the reliability of the method and in all cases satisfactory recoveries (90–108%) were obtained. Remarkable differences between MMHg levels inside both human glioblastoma and neuroblastoma cell lines were found in initial experiments, which seem to be related to different genotoxic effects.