#68716
Those embarking on attempting to chelate mercury with EDTA should as a minimum be made aware of the potential damage that the Mercury-EDTA complex can exert on the brain. You may wish to obtain and read the following article, of which I've attached the abstract
E.F. Duhr, J.C. Pendergrass, J.T. Slevin, and B.E. Haley, "HgEDTA Complex Inhibits GTP Interactions with the E-Site of Brain B-Tubulin," Toxicology and Applied Pharmacology 122, 273-280 (1993).
"We have found that EDTA and EGTA complexes of Hg2+, which conventional wisdom has assumed are biologically inert, are potentially injurious to the neuronal cytoskeleton. Tubulin, a major protein component of the neuronal cytoskeleton, is the target of multiple toxicants, including many heavy metal ions. Among the mercurials, inorganic mercuric ion (HG2+) is one of the most potent inhibitors of microtubule polymerization both in vivo and in vitro. In contrast to other heavy metals, the capacity of Hg2+ to inhibit microtubule polymerization or disrupt formed microtubules cannot be prevented by the addition of EDTA and EGTA, both of which bind Hg2+ with very high affinity. To the contrary, the addition of these two chelating agents potentiates Hg2+ inhibitiion of tubulin polymerization. Results herein show that HgEDTA and HgEGTA inhibit tubulin polymerization by disrupting the interaction of GTP with the E-site of brain B-tubulin, an obligatory step in the polymerization of tubulin. Both HgEDTA and HgEGTA, but not free Hg2+, prevented binding of (32P)8N3GTP, a photoaffinity nucleotide analog of GTP, to the E-site and displaced bound (32P)8N3GTP at low micromolar concentrations. This complete inhibition of photoinsertion into the E-site occured in a concentration and time dependent fashion and was specific for Hg2+ complexes of EDTA and EGTA, among the chelating agents tested. Given the ubiquity of Hg2+ in the environment and the widespread use of EDTA in foodstuffs and medicine, these mercury complexes may pose a potentially serious threat to human health and play a role in diseases of the neuronal cytoskeleton."