Coconut Shell Activated Carbon as Solid-Phase Extraction Adsorbent for Preconcentration of Selected Pesticides from Water Samples Ksenija Kumrić & Radojka Vujasin & Marija Egerić & Đorđe Petrović & Aleksandar Devečerski & Ljiljana Matović Received: 16 July 2019 /Accepted: 2 December 2019 # Springer Nature Switzerland AG 2019 Abstract Solid-phase extraction (SPE) on activated carbon derived from coconut shell (CSAC) for the preconcentration of four varying polarity pesticides (imidacloprid, acetamiprid, simazine, and linuron) prior to their determination using high performance liquid chromatography with diode array detector (HPLC- DAD) was investigated. The characteristics of the CSAC were analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and Brunauer- Emmett-Teller (BET) method. The effects of the solu- tion pH, eluent type, eluent volume, and flow rate were investigated for optimization of the presented proce- dure. The adsorption was achieved quantitatively on the CSAC column in the pH range of 2.0–7.0, and then the retained pesticides were eluted with dichlorometh- ane. The detection limit was found to be 0.025– 0.039 μgL -1 , depending on the pesticide. The proposed SPE-CSAC method was used to determine selected pesticides in tap water samples. The recoveries ranged from 58.2 to 105.3%, with low relative standard devia- tions. The obtained results indicated that the CSAC could be efficiently used as a low cost alternative to commercially available SPE adsorbents for the determi- nation of the varying polarity pesticides in environmen- tal water samples at trace levels. Keywords Coconut shell activated carbon . Pesticides . Solid phase extraction . Water . High performance liquid chromatography 1 Introduction Pesticides released from agricultural practices are an important class of pollutants due to their widespread use, toxicity, persistence, polar nature, and water solu- bility. Due to washing and leaching processes, these substances pass to surface and ground waters (which constitute sources of drinking water), together with their transport by the wind and their propagation through biological chains, and present a potential risk on human health and environmental safety (Zhou et al. 2007). Therefore, the presence of the pesticide residues in the environment and drinking water must be monitored. According to the EU Directive on the water quality (98/83/EC), the highest permissible concentration in drinking water is 0.1 μgL -1 for each individual pesti- cide and 0.5 μgL -1 for total pesticides concentration. Direct instrumental determination of pesticide concen- trations in the environmental samples is difficult Water Air Soil Pollut (2019) 230:302 https://doi.org/10.1007/s11270-019-4359-7 K. Kumrić (*) Laboratory of Physics, Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, Belgrade 11001, Serbia e-mail: kkumric@vinca.rs R. Vujasin : M. Egerić : A. Devečerski : L. Matović Laboratory of Materials Sciences, Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, Belgrade 11001, Serbia Đ. Petrović Laboratory of Radioisotopes, Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, Belgrade 11001, Serbia