Determination of Polycyclic Aromatic Hydrocarbons (PAHS) in Sewage Sludge and Compost by Dispersive Solid-Phase Microextraction (SPME) and Ultra-High Performance Liquid Chromatography (UHPLC) with Diode Array Detection (DAD)

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic that may degrade human health. Organic solvents are commonly used for the extraction of PAHs from solid samples and the analytes are determined chromatographically. This study describes the ultra-high performance iquid chromatography-diode array detection (UHPLC-DAD) determination of PAHs in sewage sludge and compost used as agricultural fertilizer. The PAHS may be transmitted to humans through the food chain. Analytes in the fertilizer were quantitatively extracted into the organic phase in water-dichloromethane-acetonitrile and determined liquid chromatographically. 16 PAHs were selectively extracted in a single clean-up step. For method development, the type and volume of organic solvent, pH of the water, and ultrasonic extraction time were optimized. For method validation, analytical figures of merit were obtained for the linearity, limit of detection (LOD), limit of quantification (LOQ), stability, intra- and inter-day precision, and accuracy. The developed and validated method was used for PAH determination in the fertilizers. Sample analyses were performed with 89–102% recovery values and 0.7–4.1% relative standard deviations.