Abstract
The mass fragmentographic determination of polynuclear aromatic hydrocarbons (PAH) in soils is described. Mass fragmentography, using a combination of gas chromatography and mass spectrometry, is superior to other methods because of its quick separation, specificity of mass spectra and high sensitivity. The method was as follows: i) PAH in soil were extracted with a benzene-methanol mixture (10:3) by shaking. ii) Interfering compounds were eliminated on a florisil column with benzene. iii) The concentrated benzene was fractionated on a silicic acid column. The first fraction contained aliphatic hydrocarbons, was eluted with isooctane. And the second containing the PAH with isooctane-benzene mixture (1:1). iv) A mass fragmentographic analysis (20eV) of the PAH was performed.
The recovery of PAH in soil samples was greater than 80% for those amounts ranging from 20 to 200μg. Using the present method, for soil samples collected in the Hirakata Bay area, PAH were identified as anthracene+phenanthrene, fluoranthene, pyrene, benzo(a)fluorene, benzo(a)anthracene, chrysene, benzo(a)pyrene (benzo(e)pyrene), dibenzo(a, h)anthracene and benzo(ghi)perylene, which were found to range in concentration from 0.014mg/kg to 8.44mg/kg for dry samples.
