Optimization and validation of solid phase micro-extraction (SPME) method for analysis of polycyclic aromatic hydrocarbons in rainwater and stormwater

This paper is about development of a simple and rapid solid-phase microextraction (SPME) method coupled with gas chromatography–mass spectrometry (GC–MS) for the quantitative determination of 16 polycyclic aromatic hydrocarbons (PAHs) in rainwater and stormwater samples. In this study the condition of PAHs extractions using SPME was optimized for achieving high enrichment of the analytes from aqueous samples. This condition was optimized by varying the stirring rate, salt concentration, fiber exposure time, sample pH, and sample temperature consecutively. The analysis revealed that optimal operating conditions occurred at condition of 0.5 M of sodium monochloroacetate, 65 °C, pH 7.0, agitation of 720 rpm, and an extraction time of 60 min. A desorption time of 15 min was shown to eliminate carry-over. The satisfactory linearity, detection limits and a high enrichment factor obtained prove that the method is a sensitive tool for trace level measurement. In the next step, the newly developed SPME–GC–MS method was validated for the analysis of PAHs in rainwater and stormwater samples, which resulted in high extraction recoveries from spiked synthetic rainwater and stormwater samples. This corroborates that the method is feasible for analysis of PAHs in real rainwater and stormwater analysis.