Methyltin natural water

Studies by Braman and Tompkins [98] have shown that nonvolatile methyltin species Me Sniq + (n = 1-3), are ubiquitous at ng/1 concentrations in natural waters including both marine and fresh water sources. Their work, however, failed to establish whether tetramethyltin was present in natural waters because of the inability of the methods used to trap this compound effectively during the... 

In recent years organotin compounds have been increasingly used in various technological applications that would facilitate their entry into the environment 115, 116). Methyltin compounds have been found in natural waters at very low concentrations, as have butyltin compounds 117-119). The latter probably come from widespread commercial use of butyltin compounds in antifouling paints or agricultural biocades 113, 114, 118). 

Table 115 shows the linear response curve data obtained by Braman and Tomkins using the above method for tin(IV), methyltin, dimethyltin and trimethyltin compounds. Since a 100-ml sample volume was used for natural water analyses, this places the calculated... 

De Robertis A, GianguzzaA, Giuffre O, Pettignano A, Sammartano S (2006) Interaction of methyltin(IV) compounds with carboxylate ligands. Part 1 formation and stability of methyltin(IV)-carboxylate complexes and their relevance in speciation studies of natural waters. Appl Organomet Chem 20 89-98... 

Disproportionation reactions are well known in tin chemistry and can account for the occurrence of several methyltin compounds, assuming a methyltin species was present in the first place. Similarly, transmethylation can occur between inorganic tin species and methylated forms of other elements. Examples of this nature, some of which may take place in water, are given in Section V, Reference 2. Their environmental significance is unknown. Disproportionation reactions are also covered in Section V, Reference 1. A general theory of methylation by MeCoBn was proposed, based on redox potentials51. 

Most environmental studies have focused on three distinct groups of OTCs the butyltin, phenyltin, and methyltin compounds. Differences in the chemical nature of the mono-, di-, tri-, and tetrasubstituted OTCs, particularly between the ionic and neutral forms, mean that it is difficult to find extraction methods suitable for all of the species. Extraction of the OTCs prior to their determination is required for air, water, sediment/soil, and biota samples. 

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