Development of a solventless method for the pesticides analysis

•A novel, simple, inexpensive and easily attainable green analysis method was developed for the determination of Chlorpyrifos as a case study in aqueous matrix.•Pencil graphite was electrothermaly conditioned before the sampling step.•This method does not require any time-consuming sample preparation steps.•Electrothermal conditioning increases the adsorption performance of pencil graphite.•The method can be applied for the determination of other volatile pollutants in aqueous matrix. This paper represents the results of a case study investigating the development of a novel, simple, cost-effective, solventless and sensitive chromatographic method for the determination of volatile pesticides in aqueous samples by an electrothermally prepared pencil graphite (PG). In this study, PG were conditioned by passing a suitable direct current to activate PG by Joule effect. Conditioned PG was used for the extraction of Chlorpyrifos (CP), which is used as case study. The method was also found successful in the determination of CP in real water samples, providing acceptable recovery values (82–111%).