Sorption and Desorption Dynamics of Selected Non-steroidal Anti-inflammatory Drugs Agricultural Systems
Non-steroidal, anti-inflammatory drugs (NSAIDs) are widely used pharmaceutical products with analgesic and anti-inflammatory effects that are consistently found in biosolids. Land application of biosolids is a well-established practice worldwide that introduces those NSAIDs into soils, giving rise to potential leaching to groundwater, runoff to surface waters, and accumulation in soil systems. Studies were conducted to investigate individual compound and mixture compound sorption-desorption interactions of four commonly detected NSAIDs (naproxen, ibuprofen, ketoprofen, and diclofenac) in an agricultural loam textured soil and an alkaline treated biosolids-amended soil. Sorption and desorption dynamics of ibuprofen were concentration dependent. Both studies suggest NSAIDs might compete for binding sites but synergistic sorbed to matrices in the mixed compound system. Sorption-desorption dynamics exhibited hysteresis for all NSAIDs in soil and soil-biosolid system.