Determination of the Naturally Derived Insect Control Agent Spinosad and Its Metabolites in Soil, Sediment, and Water by HPLC with UV Detection

Abstract

A method is described for the determination of the naturally derived insect control agent spinosad and its metabolites in soil, sediment, and water. The method determines residues of the active ingredients in spinosad (spinosyns A and D) and two metabolites (spinosyn B and N-demethylspinosyn D). For soil and sediment, the method has a limit of quantitation of 0.01 μg/g and a limit of detection of 0.003 μg/g. For water, the method has a limit of quantitation of 0.001 μg/mL and a limit of detection of 0.0003 μg/mL. The analytes are extracted from water, soil, or sediment using appropriate solvents, and the extracts are purified by liquid−liquid partitioning and silica solid phase extraction. All four analytes are determined simultaneously in the purified extracts by reversed-phase high performance liquid chromatography with ultraviolet detection at 250 nm. Keywords: Spinosad; spinosyn A; spinosyn D; spinosad B; N-demethylspinosyn D; soil; sediment; water; quantitation; HPLC-UV

The spinosyn family of insecticides: realizing the potential of natural products research

“…18,126 Facile sunlight-based photolytic processes are a major route of aqueous degradation along with partitioning into organic matter and sediments with subsequent biotic degradation in the absence of light. 127,128 Spinosyns also did not show a lengthy persistence in soil and litter, presumably in large part due to facile degradation by soil organisms. [128][129][130][131] Spinosyns have also been found to undergo facile metabolism in several mammals and fowl.…”

“…127,128 Spinosyns also did not show a lengthy persistence in soil and litter, presumably in large part due to facile degradation by soil organisms. [128][129][130][131] Spinosyns have also been found to undergo facile metabolism in several mammals and fowl. 18,132 Overall, the spinosyns are readily subject to a number of diverse degradative pathways and metabolic mechanisms that reduce their persistence in plants, animals and the environment.…”

Investigating Role of Abiotic Factors on Spinosad Dissipation

“…A Merck-Hitachi Lachrom HPLC system equipped with UV detector and the Windows operated integrator was used for quantitative analysis as per West (1997) with minor modifications. The column, Lichrospher, RP-18 (30 cm 9 4 mm, 5 lm) with a run time of 20 min at a flow rate of Organic carbon (%) 0.39 0.5 mL/min was used.…”

“…Investigations of abiotic (hydrolysis and photolysis) and biotic (aerobic and anaerobic aquatic) processes need to be identified to determine the degradation mechanism of spinosad. Residue analysis of spinosad utilizing high performance liquid chromatography (HPLC) with ultraviolet detector (UV) has been reported in different crops like cotton (West 1996), leafy vegetables, peppers (Yeh et al 1997), citrus (West and Turner 2000), in soil and sediment, as well as in water (West 1997). These studies were performed to meet routine regulatory requirements or to study the fate and degradation in that particular environment.…”

Fate of spinosad in litter and soils of a white spruce plantation in central Ontario

“…Spinosyns A and D and their primary degradation products DM‐A and DM‐D were determined simultaneously by reverse phase high performance liquid chromatographic (RP‐HPLC) essentially following the technique as described by West20 inclusive of purification by solid‐phase extraction. Modifications to the basic method included use of a diode‐array detector (DAD) to allow peak purity assessment and employing a Supelcosil ABZ Plus (5 µm; 250 × 4.6 mm ID) analytical column to maximize peak resolution.…”