Biomonitoring of pesticides in urine by using isoamyl acetate as a sustainable extraction solvent

The protection of the health and safety of workers in the agricultural sector requires the assessment of human exposure to pesticides through biomonitoring programs. In doing this, the health and safety of laboratory analysts should be also protected through the use of analytical procedures as safe as possible. According to Green Analytical Chemistry and Green Sample Preparation principles, the use of miniaturized extraction techniques such as dispersive liquid-liquid microextraction (DLLME) should be encouraged, with the aim of limiting the consumption of chemicals (solvents and reagents) and energy, as well as the production of wastes. Moreover, safer and more environmentally friendly alternatives to petroleum-derived solvents must be found. In this regard, the effort of researchers is focused on the development/identification of sustainable solvents, some of which have been ranked according to their disposal, environmental, safety, and health features. Here, we introduce the alternative use of isoamyl acetate ("banana oil") as sustainable extraction solvent. Compared with the trendy class of eutectic solvents (ESs), isoamyl acetate is advantageous because it is already in the liquid state, which fasters operations, and because it can be evaporated to dryness and reconstituted in a solvent compatible with the mobile chromatographic phase, which is not an option for ESs. The applicability of isoamyl acetate has been here evaluated for the first time to extract 12 pesticides of different polarities from urine matrix, by using a DLLME approach. The HPLC/MS validated method has proven to possess the sensitivity, precision and accuracy required to reliable bioanalytical methods. Its cheapness, simplicity and quickness make it an ideal sustainable choice for the screening of large numbers of samples in health monitoring programs involving people occupationally-exposed to pesticides.