Different approach to determination of pyrethroid pesticides in ornamental plants

The aim of the presented research was to develop and optimize a methodology, particularly dedicated for the quantification of pyrethroids in ornamental plant material on the basis of a rose (Rosa hybrid) with the use of HPLC chromatography and QuEChERS extraction method. High repeatability and reproducibility of the results were obtained by using acetonitrile as an eluent. The determined limits of detection and quantification for deltamethrin equal 5.2 ng and 9.3 ng per 1 cm3 of analysed solution respectively. For cypermethrin these values were: LOD 1.2 ng, LOQ 5.0 ng per 1 cm3 of solution. It has been shown that solutions of deltamethrin and cypermethrin are of high stability – they can be stored at room temperature for as long as 28 days without a change in the concentration. The experiments presented showed that the QuEChERS extraction of deltamethrin from the tested samples can be performed with efficiency above 93% using acetonitrile as a solvent, magnesium sulphate and sodium acetate as the separation salts. For purification Supel ™ QUE sorbent by Supelco was successfully applied. The described analytical method may be a valuable and relatively cheap tool to control the amounts of these pesticides sprayed in environment, wherever there is a suspicion of their excessive use.