Those who make EIS at home have no way to observe directly the fate of the silver they ingest, and the pathways by which it is reaches its final destination.
But a fair amount of information was gathered in the 1950s to 1980s using radio-silver tracers. The chief isotope of silver was Ag110m. It was produced artificially in a nuclear reactor, has a half-life of about 250 days, decays with beta and gamma emissions, and traced the concentration of silver in space and time using various radiation detection methods, including x-ray film. There was even a human in vivo observation of the fate of silver using Ag110m tracing. It resulted from an accident at a nuclear reactor in the 1960s in which a reactor technician inhaled an unknown amount of Ag110m. This episode is described by D. Newton and A. Holmes in Radiat. Res. 29:403-412 in an article titled "A Case Of Accidental Inhalation Of Zinc-65 And 110Ag." (1966.) Various animal in vivo studies using Ag110m radiosilver have also been done.For example, K.G. Scott and J.G. Hamilton published in 1950 in Publ. Pharmacol. 2:241-262 an article titled "The Metabolism Of Silver In The Rat With Radio-Silver Used As An Indicator." And, J.C. Gammill, B. Wheeler, E.L. Carothers and P.F. Hahn published in 1950 in Proc. Soc. Exp. Biol. Med. 74:691-695 an article titled "Distribution Of Radioactive Silver Colloids In Tissues Of Rodents Following Injection By Various Routes." A summary of the results of such studies can be found in Appendix 9 (p. 324-354) of the National Research Council's text "Spacecraft Water Exposure Guidelines For Selected Contaminants," Volume 1 (2004 ed.) Best regards, Matthew
