Ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) was used for the determination of different chemical classes of analytes for the first time. Limits of quantification (LOQs) ranged from 0.5 to 2.5 µg L −1, and the linearity ranged from the LOQ of each compound to 50 µg L -1. Recoveries ranged from 70 to 120% for the compounds, with relative standard deviations less than 18%. The proposed method demonstrates for the first time that sample preparation by IL-DLLME and determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be used successfully for the simultaneous extraction of 19 kinds of pesticides and 16 PPCPs from water samples. In addition, to eliminate the environmental risk of waste solvent disposal, this technique uses a low-toxicity extraction solvent. Finally, the analytical method proposed was applied successfully in analysis in surface water samples.
Keywords: IL-DLLME, water, pesticides, PPCPs, LC-MS/MS
IntroductionIn recent decades, many synthetic organic compounds detected in water samples have attracted people's attention. Pesticides, pharmaceuticals and personal care products (PPCPs) 1 have also been detected and are investigation targets. 2 Pesticides play an important role in increasing agricultural productivity. Their use in agriculture is inevitable, still being the most effective tool in the fight against weeds and pests. They are not only used for agricultural purposes, but also in forest and environmental preservation areas. Although the use of pesticides in agricultural applications provides a wide range of beneficial effects, their extensive use has been a concern because of hazards to the environment. 1,3 Toxic effects on humans, such as acute neurological toxicity, impairment of neurological development, possible dysfunction of the immune, reproductive and endocrine systems, cancers, chronic kidney disease and other potential diseases have been reported in many papers. 4,5 PPCPs are used to prevent or treat human and animal diseases or to improve the quality of daily life. They have emerged as a major group of environmental pollutants over the past decades since some of them are produced and used in large quantities. 2 Various investigations indicate that many of them can hardly be totally removed during the water treatment process. Many PPCPs are persistent or pseudo-persistent in the environment and are toxic to non-target organisms. They also have the potential to bioaccumulate in different trophic level organisms. 2,6 To quantitatively evaluate the fate of these chemicals and ensure the quality of drinking water, effective analytical methods are extremely necessary. Since the concentrations of pesticides and PPCPs in water are generally very low (ng L -1 or less), extraction techniques are needed prior to chromatographic determination. 7 The most commonly used methods are liquid-liquid extraction (LLE), 8,9 and solid phase extraction (SPE).10,11 These techniques, however, are time consuming and use large amounts of organic solvents. Thus, the ...
