Polycyclic aromatic hydrocarbons (PAHs) in peat and plants from selected peat-bogs in the north-east of Poland

Abstract

The concentrations of polycyclic aromatic hydrocarbons (PAHs) were analyzed in samples of peat and of two plant species (Pinus sylvestris and Ledum palustre) overgrowing peat-bogs in the northeast of Poland. Peat samples were collected from different depths according to the stratigraphie profile of the peat bogs. The total concentrations of the 16 anthropogenic PAHs (15 from the US EPA list and benzo[e]pyrene) in all peat samples were between 70 and 439 ng g-1. The concentration for the same compounds in pine needles (Pinus sylvestris) and Dutch Myrthe leaves (Ledum palustre) varied between 194 and 1039 ng g-1. A noticeably high fluorene concentration in Dutch Myrthe leaves was found at some sites. In all peat samples 3-ring compounds were predominant (55 to 319 ng g-1). There were less 4-ring PAHs (15 to 110 ng g-1) and the least common PAHs were 5-ring and 6-ring compounds (0 to 81 ng g-1 for both groups). In some peat samples, the perylene concentration largely exceeds of the total concentration of all the other PAHs investigated. The high content of perylene in bottom layers could result from the processes of perylene sorption from water during peat-bog formation or from biogenic formation of perylene.