Determination of Pyrethroid Residues in Wooden Toys by Gas Chromatography and Gas Chromatography-Mass Spectrometry

A novel method for the determination of pyrethroid pesticide residues in wooden toys was developed. Wooden toy samples were extracted with petroleum ether-acetone (1 : 1, v/v), cleaned up on a florisil solid phase extraction cartridge and determined by gas chromatography equipped with electron capture detector (GC-ECD), followed by validation using gas chromatography-mass spectrometry (GC-MS) with negative chemical ionization. Calibration curves were linear in the range of 0.02-0.5 mg/kg with correlation coefficients exceeding 0.9975 for GC-ECD and GC-MS. At spiked concentrations of 0.1, 0.2 and 0.5 mg/kg, the average recoveries and relative standard deviations were 82-97% and 1.5-7.8%, respectively. The limit of quantification for each analyte was 0.1 mg/kg, which satisfied the current maximum residue limit permitted in wooden toys. Results also showed that the developed method could be successfully applied to determine permethrin, cypermethrin, cyfluthrin, deltamethrin residues in real wooden toy samples.