Determination of pentachlorophenol (PCP) in waste wood--method comparison by a collaborative trial.
Two independently developed and validated procedures for the determination of pentachlorophenol (PCP) in waste wood were compared by means of a collaborative trial. Both methods foresee quantification of PCP by gas chromatography (GC-ECD) after acetylation and differ with regard to the use of methanol or toluene/sulphuric acid, respectively, as solvent in the sonication extraction step. Test samples with established analyte homogeneity were prepared from a ground "real life" starting material. A total of 23 participating laboratories with experience in wood preservative analysis were instructed to apply both methods to three levels of content in the range of 0.5-20 mg PCP/kg. In case of the toluene/sulphuric acid extraction, lower recoveries and higher interlaboratory dispersion of results at the higher PCP contents were observed. Seen against the background of the Horwitz equation a reproducibility standard deviation of approximately 19% for the methanol extraction at the 4.5 mg/kg level meets the requirement for a sound analytical method. Thus, the sonication extraction procedure with methanol has been annexed as a reference method to the German waste wood regulation.
Federal Institute for Materials Research and Testing BAM, Berlin, Germany. roland.becker@bam.de
Roland
R
Becker
Hans-Gerhard
HG
Buge
Tin
T
Win
D002623:Chemistry Techniques, Analytical / Q000379:methods; D002849:Chromatography, Gas; D004784:Environmental Monitoring / Q000379:methods; D000432:Methanol; D015588:Observer Variation; D010416:Pentachlorophenol / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D012037:Refuse Disposal; D015203:Reproducibility of Results; D012995:Solubility; D014934:Wood
D010575:Pesticides; D010416:Pentachlorophenol; D000432:Methanol