Trace analysis of pentachlorophenol (PCP) in wood and wood-based products - comparison of sample preparation procedures

The main problem with routine analyses of pentachlorophenol (PCP) and sodiu m pentachlorophenolate (Na-PCP) in wood and wood-based products is to deter mine critical PCP-contents. This task requires a reliable analytical method and statistical testing. An analytical procedure is described, which permi ts the determination of PCP and Na-PCP with sufficient sensitivity and accu racy. A medium size sieve (4 x 4 mm quadratic mesh) was found suitable for the grinding step. Different extraction techniques and solvents were tested systematically. Extraction by a combination of ultrasonication and shaking in the solvent mixture toluene/sulfuric acid showed best recoveries. The e luted PCP and Na-PCP were derivatized with acetic anhydride and determined by GC/ECD. The limits of detection and determination were 0.14 mg/kg and 0. 40 mg/kg, respectively.