6 research outputs found
Distribution and characteristics of PAHs in the central and eastern part of the Yellow Sea
No full textDistribution 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/1
Occurrence and Characteristics of Organochlorin pesticides and PCBs in Yellow Sea
No full textOrganochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are important persistent organic pollutants (POPs). Their persistency, bioavailability, high toxicity and long range atmospheric transport have aroused global concern since 1960s. Hence, an international treaty, Stockholm Convention, was adopted to protect human health and the environment from persistent organic pollutants (POPs) in 2001, and entered into force in 2004. The convention nominated 12 compounds (aldrin, dieldrin, endrin, chlordane, heptachlor, HCB, DDTs, toxaphene, mirex, PCBs, dioxins, and furans) as high priority POPs. To assess the contamination status and distribution characteristics of persistent organochlorine pollutants in the Yellow Sea, we collected samples of various environmental matrixes such as sediment, seawater, and air on board R/V Eardo in September 2004 and October 2005, and analyzed 22 OCPs and 89 PCB congeners. Sampling covered half of the continental self system of the Korean side, including a dumping zone ‘Byung’. OCPs and PCBs were detected in all the matrixes from Yellow Sea. Among 87 surface sediment sampling sites, 3 or 4 sites showed PCBs, DDTs, and chlordane concentrations exceeding the effect range low (ERL) values for benthic organisms which is suggested by Long et al. (1995). All sites above the ERL values of PCBs, DDTs, and chlordanes are located in the dumping site ‘Byung’, implying that a dumping site could be a source of POPs in the Yellow Sea. However, all the concentrations are lower than the effect range median (ERM) values of each chemical. Except for 2 or 3 dumping sites, OCPs and PCBs are homogeneously distributed in the Yellow Sea. The general concentration of PCBs, DDTs, and chlordanes are relatively lower than those from Korean coastal regions; however HCH concentrations showed similar level. Among the target organochlorine compounds, PCBs, DDTs, and HCHs were major contaminants in this region. But their compositions are diverse accordi1
Spatial and vertical distribution of persistent organic contaminants in sediments and suspended particles from the Yellow Sea
No full textPersistent organic pollutants such as polychlorinated biphenyls, DDTs, HCHs, and other organochlorine pesticides were measured in sediment and suspended particles collected from the Yellow Sea in 2004. Among the target organochlorine compounds, PCBs, DDTs, and HCHs were major contaminants in this region. Their maximum contamination levels in sediments, except for those in dumping zone, are comparable to about 60% of levels determined in overall Korean coastal sediments. However, the concentration levels in dumping zone were similar to those found in industrialized coastal regions of Korea. Especially, high levels of DDTs and HCHs were determined in sediment layer of the dumping zone, indicating that this zone can be a source of these pesticides in the Yellow Sea. Sediment and suspended particle showed the same homologue composition of PCBs with tri- and tetra-chlorinated CBs as dominant isomers. In the water column, most target organochlorine compounds showed high concentration in the upper layer and then gradually decreased towards the bottom, indicating that atmosphere is the major input pathway of the persistent organic contaminants to the marine environment.1
