COMPARATIVE STUDY OF EXTRACTION METHODS FOR THE DETERMINATION OF PAHS IN SOILS USING GC-MS

Abstract

Soil contamination by polycyclic aromatic hydrocarbons (PAHs) is a widespread concern due to the high potential for human exposure through inhalation, ingestion, and dermal contact. In this study, we compared the efficiency of three different methods for PAHs extraction from model samples, including ultrasonic (US), mechanical shaking and purification with commercial QuEChERS kit (Shq), and ultrasonic extraction coupled with QuEChERS (USq) by gas chromatography coupled to a triple quadrupole tandem mass-spectrometry (GC-MS). The results showed that in the ultrasonic extraction with subsequent purification using QuEChERS, the content of PAHs in the sample varied from 86.91 to 2211.60 ng/g. Whereas, in mechanical shaking method, this range was in the range 1.56-761.20 ng/g. In the case of ultrasonic extraction without sorbent purification, only for acenaphthene, fluorene, and benzo(g,h,i)perylene, the values were higher compared to the other two methods: 285.78�27.56 ng/g, 577.48�73.62 ng/g, and 266.35�177.30 ng/g, respectively. The comparison of PAH extraction efficiency showed that the combination of ultrasonic extraction and purification with QuEChERS (USq) was the most efficient method and rapid, obtaining the highest yields for all tested PAHs.