Distribution and characteristics of PAHs in the central and eastern part of the Yellow Sea

Abstract

Distribution of polycyclic aromatic hydrocarbons (PAHs) in the surface sediment and suspended solids in the central and eastern part of the Yellow Sea were investigated. Surface sediments and suspended solids were sampled along the six cruise lines from 34o N to 36.5o N. Concentrations of sixteen PAHs in the surface sediment ranged from 4.28 ng/g to 634 ng/g with mean value of 44.9 ng/g. The Dumping site samples showed higher concentration compared to other cruise line samples. Average concentration of dumping sites was 134 ng/g and followed by B line (52.0 ng/g), E line (37.9 ng/g), A line (34.8 ng/g) and other lines (less than 21.0 ng/g). B line and E line which are located near dumping sites showed elevated PAHs levels. Generally total PAHs concentration increased from eastern to central part of the Yellow Sea due to the mean grain size and total organic carbon contents. But B line and E line were more influenced by proximity of dumping site than sediment textiles or organic carbon contents. Combustion related high molecular weight PAHs were dominant in the most of samples, and some of dumping site samples showed petroleum related PAH profiles. And naturally occurring PAH, perylene was also highly detected in the A line samples which were presumably affected by the riverine inputs. Vertical profiles of PAHs in sediment cores were also determined at the Sts. D10 and E8. Background concentrations (6 ng/g) were commonly found at both stations. Background stage (34 – 16 cm), slight increase stage (16 – 10 cm) and rapid increase stage (10 cm – surface) were distinguished at the E8 core. This categorization is thought to reflect the PAHs loads in the study area for the past decades, thus historical changes of nearby regions’ industrialization.Suspended solids (SS) were sampled using high volume SS sampler, which were specially designed for filtering more than 100 liters of seawater. Total PAHs in the SS were in the range of 0.064 – 0.817 ng/