Soil contamination by petroleum substances in the vicinity of oil production wells.
Joanna Wartak, Katarzyna Chruszcz-Lipska, Ewa Knapik, Stanisław Rychlicki
Vol. 33, no. 4 (2016), s. 723-730, 
The paper presents the study of various indicators of soil contamination by petroleum substances from the area of active exploitation of oil deposits in the south of Poland. Nineteen studied soil samples were taken directly around the production wells (0–1 m) or their vicinity (1–7 m) at a depth of 0.1 to 0.3 m. Collected samples were tested for the presence of benzene, toluene and xylene (BTX), and polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene, anthracene, fluoranthene, fluorene, pyrene, benzo(a)anthracene, chrysene, benzo(a)pyrene, dibenz(a,h)anthracene and benzo(g,h,i)perylene. An analysis of the content of these chemical compounds in the soil samples was performed by gas chromatography. The observed results were interpreted to determine the hazard for the natural environment and human health. The evaluation of soil samples was based on the new Regulation of the Ministry of Environment of 1 September 2016 regarding the assessment of contamination of the surface of the earth (Journal of Laws 2016 Nr 0, item 1395) as well as guidelines presented by the Institute of Soil Science and Plant Cultivation (ISSPC).