Changes in the concentration levels of polycyclic aromatic hydrocarbons in the soil – a case study of a city in southern Poland

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds considered carcinogenic, teratogenic and mutagenic, and they can migrate into soil and water environments. The aim of this article is to present potential changes in PAH concentrations in the tested soil samples from the city of Będzin, located in southern Poland, across two measurement series, and to identify potential sources of contamination. Thirty soil samples were collected in two measurement series. Sample locations associated with high traffic intensity and power plants showed higher average concentrations of PAHs in late spring. In contrast, locations associated with high population density showed higher concentrations in late autumn. The average concentration of the analyzed PAHs (PAH_sum) in 15 soil samples from the first sampling (A) was 151 µg/g, while from the second sampling (B) it was 246 µg/g. The values of the ΣPAH_carc/ΣPAH toxicity index in all tested soil samples remained below 0.4. The current level of soil contamination in this region indicates greater accumulation of PAHs from former industrial plants than from current ones. Despite this fact, continuous monitoring of these compounds is important to prevent the migration of contaminants into aquifers.