Occurrence of n-alkanes and polycyclic aromatic hydrocarbons in the core sediments of the Yellow Sea

Three core sediments (YSA10, YSB7 and YSC5) were collected from the Yellow Sea to determine the composition of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) by GC. Concentrations and distributions of n-alkanes (n-C14 to n-C33) vary from 0.7 to 15.8 μg g−1 dry weight in these core sediments. The alkane indexes (CPI and U/R) confirm that vascular plant inputs predominate in all three cores, a potential petrogenic contamination in YSC5 and YSB7 can be identified. Riverine input seems to be the major contribution of n-alkanes compared with atmospheric deposition. Total concentrations of 13 individual PAHs range from 370 to 3800 ng g−1 dry weight. Perylene is found in nearly all samples, and a diagenetic origin is indicated for this compound. Except for a few samples, the YSB7 and YSA10 cores are characterized by a major pyrolytic influence. The distribution of PAHs in Core YSC5 shows a mixture of influences by pyrolytic and petroleum contamination, while pyrolytic source is predominant input in YSA10 and YSB7 cores. The change in PAHs from the core samples is related to the continental use of fossil and fuel. Atmospheric input plays an important role of anthropogenic PAHs in the core sediments. Legal curbs of industrial and vehicle emissions should be done to prevent the increasing contamination of PAHs in the Yellow Sea.