Determination of Xenobiotic Imidacloprid Content in Surface Waters

Abstract

Surface water is contaminated by various xenobiotics. Using standardized methods, the content of organochlorine pesticides that are environmentally stable, migrate along food chains and can accumulate in dangerous amounts in living organisms is monitored. In this case, the insecticide imidacloprid is not controlled, however, its ingress into surface and ground waters is not allowed. Seasonal detection of imidacloprid in fish tissues may indicate a violation of regulations for working with imidacloprid preparations. To ensure the necessary preventive regulation and to protect surface water from imidacloprid contamination, a methodology is needed for laboratory monitoring of the general sanitary level of imidacloprid in surface waters. In this work, imidacloprid extracts were obtained based on the liquid-liquid extraction method, the optimal conditions for the quantitative analysis of imidacloprid were determined using high-performance liquid chromatography with a spectrophotometric (diode array detector) detector (HPLC/DAD). The limit of detection of the imidacloprid, which was reached in the work, is 0.15 µg/mL, the limit of quantification is 0.7 µg/mL. Taking into account preliminary concentration (100 times), the lower limit of imidacloprid detection in water is 0.0015 mg/L, the range of determined contents is 0.007–0.028 mg/L. The developed method is simple to perform, allows us to measure the imidacloprid content in one water sample by 90 minutes. The method can be used for monitoring studies of the imidacloprid content in surface water, to collect the water pollution data and forecast its impact.