A multiresidue analytical method for the determination of organic contaminants in agricultural soil

Abstract

Agricultural pollution is one of the biggest environmental concerns regarding the contamination of both soil and water resources. Owing to the mobility of pollutants in soil-water system, contamination of soil can be considered as a risk factor for the human health as well as aquatic ecosystem. Therefore, monitoring of soil contamination has a prime importance not only for the evaluation of the risk for the environment but also for the development of treatment and remediation methods for contaminated sites. Hence, development of a multiresidue analytical method was targeted for a wide range of chemicals selected from 39 frequently used pesticides in rice cultivation and 28 industrial pollutants detected in water samples collected from Ergene River in 2017-2018. Simultaneous extraction of the target analytes from soil samples and their quantification were performed with acetate buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) method and liquid chromatography coupled with tandem mass spectroscopy (LC-MS/MS), respectively. The developed method gave satisfactory recoveries within 70-120% for 78% of the target compounds. The method was applied to 22 soil samples collected from mainly paddy fields located in southwestern Thrace region adjacent to Ergene River in order to determine the agricultural pollution caused by the pesticide application and irrigational activities. The residues of the selected pesticides were found in all soil samples within the concentration range of 0.04-406 µg/kg, whereas the industrial pollutants were dominantly detected in soil samples taken from paddy fields as 0.05-807 µg/kg.