Arsenic is one of the major pollutants in water resources which are highly toxic to consumers. Recently, a new class of adsorbents has been used to remove environmental pollutants such as Zeolite iImidazole Frameworks (ZIF-8). The aim of this study was to synthesise ZIF-8 and optimise for arsenic adsorption. The prepared ZIF-8 was characterised by FTIR, XRD, EDX, FE-SEM, and BET surface area. The ZIF-8 performance was assessed for variables such as initial arsenic concentration, pH, adsorbent dosage, and contact time. To measure the residual arsenic concentration, ICP-OES was used. Morphology of the synthesised ZIF-8 was dodecahedral. The particle size of synthesised ZIF-8 was in the range of 420 nm to 744 nm. The surface area of dodecahedral-ZIF-8 was 1566 m² g⁻¹. The study findings showed that experimental data could be well represented by the pseudo-second-order model and the Langmuir isotherm model. The arsenic adsorption on ZIF-8 was endothermic. The results of this study showed that ZIFs can be used to remove environmental pollutants effectively.

The pesticide residues in agricultural products and foods have become a serious concern. A simple, inexpensive, reliable and environmentally friendly method based on ultrasound-assisted dispersive liquid–liquid microextraction and the solidification of floating organic drops (UA-DLLME-SFO) followed by high performance liquid–liquid chromatography-ultraviolet detection (HPLC-UV) was developed for the simultaneous determination of phosalone and chlorpyrifos in fresh vegetables. Samples were homogenized and the extraction of the target analytes with acetone was carried out assisted by sonication. No clean-up or evaporation was required after extraction. Pre-concentration of the analytes from the acetone extract was done using a DLLME-SFO technique. 1-Undecanol was added in a micro-level volume as an extraction solvent in the DLLME-SFO procedure. Some effective parameters on extraction were studied and optimized. Under the optimum conditions, recoveries for different vegetables are in the range of 68–88%. The calibration graphs are linear in the range of 5–800 μg kg⁻¹ and limit of detection (LOD) values are in the range of 2–8 μg kg⁻¹. The repeatability (intra-day) and reproducibility (inter-day) for 50 μg kg⁻¹ of phosalone and 200 μg kg⁻¹ of chlorpyrifos in vegetables are in the range of 4.5–7.8% and 5.1–9.0%, respectively (n = 5). The method allowed the determination of OPPs in fruit and vegetables at lower concentrations than the migration limits established by the European Union. The obtained results show that UA-DLLME-SFO combined with HPLC-UV is a fast and simple method for the determination of pesticides and herbicides in fresh vegetables.