Distribution of polycyclic aromatic hydrocarbons and n-alkanes in surface sediments from Shinano River, Japan.

The distribution of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes was investigated in the surface sediment from the Shinano River in Niigata, Japan. The total concentrations of the PAHs and n-alkanes ranged from 102 to 10,450 ng/g dry weight and from 160 to 3,530 ng/g dry, respectively. Perylene (Per) in the sediment samples originated from both the same anthropogenic sources as benzo[a]pyrene and the natural sources; the anthropogenically derived Per was estimated at 0.4%-27% of the Per in the sediment. The carbon preference index values ranged from 0.77 to 2.48, suggesting the differences in the n-alkane sources at the investigated sites. The investigated sites were divided into three clusters by the cluster analysis.