Metabolism of inorganic arsenic to organoarsenicals in rainbow trout (Salmo gairdneri)

Chemical speciation of arsenic was examined by radioactive tracer and chromatographic techniques applied to muscle, liver, kidney, blood, bile, and urine from rainbow trout (Salmo gairdneri) given an oral dose of ⁷⁴As as arsenic acid. Conversion to organic forms of arsenic was rapid and extensive. The ratio of total organic to inorganic increased with time in all tissues, with the organic arsenic fraction accounting for about 50% at 6 hr and over 80% at 24 hr. An organoarsenic metabolite was shown by thin-layer chromatography to have the same R_f as ethylarsenobetaine, and this compound accounted for the major portion of the total arsenic in all tissues including bile and urine sampled 24–96 hr postdose.