Validation interlaboratory trial for ISO 12010 : water quality-determination of short-chain polychlorinated alkanes (SCCP) in water
Résumé
A validation interlaboratory trial was carried out to prepare ISO 12010: Water quality-Determination of short-chain polychlorinated alkanes (SCCP) in water-Method using gas chromatography/mass spectrometry (GC-MS) and electron capture negative ionisation (ECNI). The task was to determine the sum of short-chain polychlorinated n-alkanes with carbon chain lengths of C-10-C-13 and a chlorine content between 49% (g/100 g) and 67% (g/100 g) in water by GC-ECNI-MS. The quantification had to be performed by multiple linear regression as described in ISO/DIS 12010, the compulsory method. Samples distributed were real river samples, and waste water spiked with a target concentration of 0.4 and 0.6 mu g/L for the sum of SCCPs, i.e. a concentration around the environmental quality target level according to the European Water Framework Directive. The different types of water samples tested were surface water with <150 mg/L suspended matter, surface water with 0.5 g/L suspended matter, and filtered waste waster. The interlaboratory trial included the extraction of the water samples, a column chromatographic clean up, a concentration step, and integration of chromatographic unresolved complex mixtures as well as the calibration and quantification by multiple linear regression. The reproducibility standard deviation of the standard concentration was 11.9%. Reproducibility standard deviations of concentrations in the three different water samples between 27.8 and 34.2% were achieved by 10-12 participating laboratories from six countries.