Meconium is the earliest stool of newborns. It is a complex matrix that reflects the degree of fetal exposure to environmental pollutants. To investigate exposure to xenobiotics, an analytical method was developed to identify and quantify some pesticides and their metabolites and BTEX metabolites in meconium. Samples were prepared by two liquid-solid extractions and purified twice using SPE cartridges, followed by analysis with liquid chromatography coupled with tandem mass spectrometry. SPE cartridges (polymeric phase with hydrophilic and hydrophobic interactions, ion exchange, mixed mode) were tested and matrix effects were evaluated to determine purification performance. The quantification limits in meconium of this multi-residue method were in the range of 30 ng g(-1). The analytical method was applied to "real" meconium samples. Some target analytes were determined in most samples.

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An analytical method was developed to measure cis-permethrin and trans-permethrin in different biological rat matrices and fluids (whole blood, red blood cells, plasma, brain, liver, muscle, testes, kidneys, fat and faeces). The method was also suitable for the simultaneous quantification of their associated metabolites [cis-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (cis-DCCA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (trans-DCCA) and 3-phenoxybenzoic acid (3-PBA)] in blood (whole blood, red blood cells, plasma) and liver. The target analytes were derivatised in samples using a methanolic/hydrochloric acid solution and then extracted with toluene. The analysis was performed by gas chromatography, and detection using ion trap tandem mass spectrometry. The selectivity obtained for complex matrices such as rat organs allowed the use of a purification step to be avoided for most of the matrices investigated. In the case of fat, where permethrin is suspected to accumulate, a dedicated purification step was developed. In fluids, the limits of quantification were at the 50 ng/mL level for the parent compounds and 3-PBA and at 25 ng/mL for cis-DCCA and trans-DCCA. For solid matrices excluding fat, the limits of quantification ranged from 50 ng/g for muscle to 100 ng/g for brain and testes for both cis-permethrin and trans-permethrin. The extraction recoveries ranged primarily between 80 and 120% for the matrix tested. The stability of blood samples was tested through the addition of 1% v/v formic acid. The methods developed were applied in a toxicokinetic study in adult rats. cis-Permethrin and the metabolites were detected in all corresponding matrices, whereas trans-permethrin was detected only in blood, plasma and faeces.

Meconium is the first fecal excretion of newborns. This complex accumulative matrix allows assessing the exposure of the fetus to xenobiotics during the last 6 months of pregnancy. To determine the eventual effect of fetal exposure to micropollutants in this matrix, robust and sensitive analytical methods must be developed. This article describes the method development of liquid chromatography methods coupled to triple quadrupole mass spectrometry for relevant pollutants. The 28 selected target compounds had different physico-chemical properties from very polar (glyphosate) to non-polar molecules (pyrethroids). Tests were performed with three different types of columns: reversed phase, ion exchange and HILIC. As a unique method could not be determined for the simultaneous analysis of all compounds, three columns were selected and suitable chromatographic methods were optimized. Similar results were noticed for the separation of the target compounds dissolved in either meconium extract or solvent for reversed phase and ion exchange columns. However, for HILIC, the matrix had a significant influence on the peak shape and robustness of the method. Finally, the analytical methods were applied to "real" meconium samples.

A first preliminary interlaboratory trial was planned to prepare ISO/DIS 12010: Water quality -determination of short chain polychlorinated alkanes (SCCP) in watermethod using 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 and 67% in water by GC-ECNI-MS and quantification by multiple linear regression described in ISO/DIS 12010 as the compulsory method. Distributed samples were obtained from a real water extract spiked with a target concentration of 0.4 mg/mL sum of SCCP, i.e. the environmental quality target level according to the Water Framework Directive. The interlaboratory trial included the calibration, a column chromatographic clean up, a concentration step and an integration of chromatographic unresolved humps as well as the quantification with multiple linear regression. Reproducibility standard deviations between 21.5 and 22.9% were achieved by 17 participating laboratories from four countries. The method outlined no significant difference of the results between the standard solution and a real water matrix extract. On the basis of this succeeded preliminary interlaboratory trial the final interlaboratory trial for validation of ISO 12010 was prepared in autumn 2010.