POLYCYCLIC AROMATIC HYDROCARBONS IN TWO SEDIMENTARY ENVIRONMENTS OF THE TERTIARY KREPOLJIN COAL BASIN

In the present study, statistical correlation analysis and multivariate statistical techniques (PCA/FA) were employed to investigate polycyclic aromatic hydrocarbons (PAHs) in sediments, such as illite-montmorillonite (IM) and calcite (Ct), from two sedimentary environments of the Tertiary Krepoljin brown coal basin in Serbia. The coal and sediment layers were formed in fresh-water bogs during the Lower Miocene period. The total amount of extractable PAHs was determined by gas chromatography with a triple quad mass detector (GC-MS-MS), and it ranged from 449 to 10585 & mu;g l-1 in all sediments. Eight of the total 16 PAHs, which ranged from 175.17 to 658.42 & mu;g l-1, include benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, which are regarded as potentially carcinogenic, indicating a higher possibility of adverse ecological effects. Medium molecular-weight (MMW) PAHs were found to be predominant in all sediments. PAH concentrations are affected by several factors, such as carbon content, H/C mole ratio, and (less significant) O/C mole ratio. The non-existence of a correlation between the N/C ratio and other parameters indicates unspecific changes which accompany the original organic matter. The lower-sulfur Ct sediment samples were found to have a higher PAH content than higher sulfur IM samples, leading to the conclusion that the PAH content of sediments may be related to the depositional environment.

Automated summary

This study investigated polycyclic aromatic hydrocarbons (PAHs) in sediments from the Tertiary Krepoljin brown coal basin in Serbia using statistical correlation analysis and multivariate statistical techniques. The total extractable PAHs ranged from 449 to 10585 μg/l in all sediments. Several potentially carcinogenic PAHs were identified, indicating adverse ecological effects. Medium molecular-weight PAHs were found to be predominant in all sediments, and PAH concentrations were influenced by factors such as carbon content and H/C mole ratio.