[Transformation reactions of special metals in organisms and in the environment. 2. Abiotic methylation reactions of mercury, especially by methyltin compounds and humic and fulvic acids].

Following a literature survey concerning abiological methylation reactions including transmethylation of mercury we present the results of transmethylation experiments. Model experiments in aqueous solution show an instantaneous methylation of mercuric chloride by mono-, di-, and trimethyltin chloride, the dimethyl compound having the highest rate of formation. The same is valid for similar experiments with soils, in which influences of the kind of soil also play a certain role. The methylation experiments of HgCl2 with humic and fulvic acids isolated from soil yielded positive results only in some few of the extracts and only with humic acid fractions.