Methylmercury-methylcobalamin 1mg/day model Hi Rick, Based on this available information I built an Excel model including the half-life, body load at earliest toxic effects of methyl mercury and 3 potential rates of utilization of methylb12 in methylating mercury in the body. It probably needs refinement and may have bugs. If you would like a copy of the Excel spreadsheet send me your email via private message. I assumed limited body loads of 30mg and 50mg and cut off conversion after that where applicable and demonstrated falling body load and serum level as would be expected with a 76 day serum half-life. I present this as a possiblity, a hypothesis to answer the question you asked. How does it sound to you? Did I forget anything important? Am I misinterpreting something. Does this fly? This question about mercury came up very early in my mb12 usage, a pain doc/professor I know who edits a journal as well. He asked about mercury. Maybe now 5 yeqars later I might be on the path to giviong him an answer. Methylmercury - Methylcobalamin 1mg/day Model Version 1.0 - 08/24/09 Just a few terms and numbers that figure into this. "Methylmercury" is a shorthand for "monomethylmercury", and is more correctly "monomethylmercuric cation" Methylcobalamin has 1344.4 grams/mol. Mercury has 200.59 grams/mol and methylmercury has 215.6247 grams/mol. It takes 6.70228mg of methylb12 to methylate 1mg of mercury. It takes .149204mg of mercury to utilize the methyl groups from 1mg of methylb12 According to the World Health Organization (WHO, 1976), the earliest effects of methyl mercury in humans occur when blood concentrations are between 200 and 500 ng/mL. These blood concentrations correspond to body burdens of 30 to 50 mg Hg/70 kg and are equivalent to daily intakes of 3 to 7 g/kg. Less than 1% of the body burden of methyl mercury is excreted daily, resulting in a biological half-life of approximately 70 days (Berlin, 1983). Over a 4-day period, a human volunteer excreted only about 6% of the ingested dose of radiolabeled, protein-bound methyl mercury, the biological half-life ultimately being 76 days (Miettinen, 1973). http://rais.ornl.gov/tox/profiles/methyl_mercury_f_V1.shtml A 76 day half-life amounts to 0.0099 loss per day, just a hair under 1%. So the question that arises is the old woodchuck question, how much wood .? What is the efficiency of conversion of mercury to monomethylmercury. At 100% efficiency, all methylb12 donating methyl group to Hg it would require 201mg to 335mg of methylcobalamin to immediately convert 30-50mg of Hg to methylmercury causing the earliest effects of methyl mercury in humans. At 10% efficiency, 10% of all methylb12 donating methyl group to Hg it would require 2011mg to 3351mg of methylcobalamin to immediately convert 30-50mg of Hg to methylmercury causing the earliest effects of methyl mercury in humans. At 1% efficiency, 1% of all methylb12 donating methyl group to Hg it would require 20,107mg to 33,511mg of methylcobalamin to immediately convert 30-50mg of Hg to methylmercury causing the earliest effects of methyl mercury in humans. So then, what is the serum level of methylmercury contributed to by 1mg of methylb12 injected daily or equivalent in sublingual? One Day At 100% efficiency - 0.147725493mg 0.984ng/ml At 10% efficiency - 0.014772593mg 0.0984ng/ml At 1% efficiency - 0.0014772593mg 0.00984ng/ml One serum half-life (76 days) At 100% efficiency - 7.913814388mg 52.758ng/ml At 10% efficiency - 0.7913814388mg 5.2758ng/ml At 1% efficiency - 0.07913814388mg 0.52758ng/ml 201 days cutoff at 30mg accumulated At 100% efficiency - 12.89302584mg 85.9533ng/ml At 10% efficiency 1.289302584mg 8.59533ng/ml At 1% efficiency - 0.1289302584mg 0.859533ng/ml 335 days cutoff at 50mg accumulated At 100% efficiency - 14.3765611mg 95.8433ng/ml At 100% efficiency cutoff at 201 days 3.394385667mg 22.6286ng/ml At 10% efficiency - 1.43765611mg 9.58433ng/ml At 1% efficiency - 0.143765611mg 0.958433ng/ml Five Serum half-lives (380 days) At 100% efficiency - 14.56805435mg 97.12ng/ml At 100% efficiency cutoff at 201 days 2.168310737mg 14.4553ng/ml At 100% efficiency cutoff at 335 days 9.183650551mg 61.224ng/ml At 10% efficiency - 1.456805435mg 9.712ng/ml At 1% efficiency 0.1456805435mg 0.9712ng/ml Ten Serum half-lives (760 days) At 100% efficiency - 14.89901603mg 99.3266ng/ml At 100% efficiency cutoff at 201 days 0.049260372mg 0.3284ng/ml At 100% efficiency cutoff at 335 days 0.208637089mg 1.3906ng/ml At 10% efficiency - 1.489901603mg 9.93266ng/ml At 1% efficiency - 0.1489901603mg 0.993266ng/ml DISCUSSION Lets consider then that it would take about 200mg of methylb12 to convert 30mg all at once with 100% efficiency to reach the lowest toxic effects level of methylmercury. While this is on top of the unknowable existent methylmercury level, we can assume that conversion isnt 100%. Considering that even a 1000mcg dose of MB12 has substantial effects as methylb12 it is obvious most of it isnt being immediately disabled by mercury, that in fact most of it is being flushed rapidly out of the body with some small number of mcgs being utilized as b12. So perhaps a 10% conversion rate is the right order of magnitude for conversion. At 10% conversion with a 76 day serum half-life the contributed level of methylmercury never gets above 10ng/ml, 5% of the minimum needed level to cause toxic effects. So it appears most likely that the only persons affected would be ones who are already sitting at the edge of toxic effect.