DS/EN ISO 23161:2011

Soil quality - Determination of selected organotin compounds - Gas-chromatographic method

This International Standard specifies a gas-chromatographic method for the identification and quantification of organotin compounds (OTCs) in soils as specified in Table 1. The method is also applicable to samples from sediments, sludges and wastes (soil-like materials). The working range depends on the detection technique*used and the amount of sample taken for analysis. The limit of quantification for each compound is about 10 ìg/kg.*Table 1 - Organotin compound, which can be determined in accordance with this International*Standard*RnSn(4.n)+ R n Name Acronym*Organotin cationsa*BuSn3+ Butyl 1 Monobutyltin cation MBT*Bu2Sn2+ Butyl 2 Dibutyltin cation DBT*Bu3Sn+ Butyl 3 Tributyltin cation TBT*OcSn3+ Octyl 1 Monooctyltin cation MOT*Oc2Sn2+ Octyl 2 Dioctyltin cation DOT*Ph3Sn+ Phenyl 3 Triphenyltin cation TPhT*Cy3Sn+ Cyclohexyl 3 Tricyclohexyltin cation TCyT*Peralkylated organotin*Bu4Sn Butyl 4 Tetrabutyltin TTBT *a Organotin compounds are measured after derivatization.**NOTE When applying this method to the determination of other organotin compounds not specified in the scope, its suitability is proven by proper in-house validation experiments, e.g. methyltin compounds. See Table 2. Methyltin cations are unlikely to evaporate from aqueous solvents, but peralkylated methyltin compounds are volatile and subject to losses (see C.3). Therefore, additional precautions are established.**Table 2 - Methyltin compounds *RnSn(4.n)+ R n Name Acronym*MeSn3+ Methyl 1 Monomethyltin cation MMT*Me2Sn2+ Methyl 2 Dimethyltin cation DMT*Me3Sn+ Methyl 3 Trimethyltin cation TMT**Organotin cations can only be determined in accordance with this International Standard after derivatization. The anionic part bound to the organotin cation is mainly dependent on the chemical environment and is not determined using this method. The peralkylated organotin compounds behave in a completely different way from their parent compounds. Tetraalkylated organotin compounds which are already peralkylated, such as tetrabutyltin, are determined directly without derivatization.*The properties, such as particle size distribution, water content and organic matter ontent of the solids to be analysed using this International Standard vary widely. Sample pretreatment is designed adequately with respect to both the properties of the organotin compounds and the matrix to be analysed.