Determination of Volatile Polycyclic Aromatic Hydrocarbons in Soil Using Needle-Type Extraction

Abstract

A new analytical method for the quantification of volatile polycyclic aromatic hydrocarbons (PAHs) in soil samples using a needle-type extraction device was developed. Naphthalene (Nap), acenaphthylene (Acy), acenaphthene (Ace), and fluorene (Flu) were investigated as analytes. Samples were prepared by placing 10 g of soil in a glass cartridge and immersing the cartridge in a 75°C water bath. The needle-type extraction device packed with Carbopack X and carbon molecular sieve was inserted into the glass cartridge, and 300 mL of gaseous sample was collected. During gas sampling, N₂ was introduced into the cartridge through the tip of the cartridge. After collecting the sample, the extraction needle was inserted into a heated gas chromatographic (GC) injection port, and the extracted PAHs were thermally desorbed followed by the GC separation on a fused-silica capillary column. The limits of quantification for Nap, Acy, Ace, and Flu were 36, 36, 15, and 36 ng through flame ionization detector and 3.6, 7.5, 7.5, and 36 ng through mass spectrometry, respectively.