Application of dispersive liquid-liquid microextraction for the determination of selected organochlorine pesticides in honey by gas chromatography-mass spectrometry

Dispersive liquid-liquid microextraction (DLLME) is a rapid and easy technique that consumes minute amounts of organic solvents. In this work, we present chemometric study on optimization of DLLME parameters for the extraction of aldrin, endrin, lindane, alpha-endosulfan, 4,4'-DDT and its metabolites from honey matrix. Method quantification limits (MQLs) vary between 0.3 ng/g for 2,4'-DDE and 4,4'-DDE to 13.2 ng/g for alpha-endosulfan and enable determination at levels below EU-established Maximum Residue Limits. The developed method is linear (R-2 > 0.994) in the investigated range (MQL-100 ng/g), with preconcentration factors of 13.2-30.5 and good repeatability (CV <= 17%). A comparison with other available methods reported in the last decade is provided. The method has been applied to 19 real samples from Poland, and the results show that organochlorine pesticides (OCPs) are present in analysed honeys at levels not posing threat to human health (below 14 ng/g for sum of 4,4'-DDT and metabolites and below 5 ng/g for aldrin, endrin and lindane). To the best of our knowledge, this is the first reported application of DLLME for the determination of OCPs in honey.