Monitoring traces of organochlorine pesticides in herbal matrices by bar adsorptive microextraction–Application to black tea and tobacco

Bar adsorptive microextraction followed by microliquid desorption and gas chromatography-mass spectrometry, under the selected ion monitoring acquisition mode, has been developed for the determination of 20 organochlorine pesticides (OCPs) in herbal matrices. Assays performed on 25 mL of ultra-pure water samples spiked at the 2.0 µg L⁻¹ level, yielded average recoveries ranging from 14.0% to 95.1% for the target OCPs, under optimised experimental conditions. The proposed analytical methodology demonstrated suitable detection limits (0.10–0.15 µg L⁻¹) and good linear dynamic ranges (0.5–100.0 µg L⁻¹) with determination coefficients equal or higher than 0.9900. The proposed methodology, by using the standard addition method, proved to be a suitable sorption-based static microextraction alternative to monitor traces of OCPs in black tea and tobacco products, in compliance with the green analytical chemistry principles.