Integrative assessment of sediment contamination by toxic substances in Busan coast, South Korea

Abstract

In order to assess the contamination status and identify the priority substances in Busancoast, an intensive sediment sampling was conducted and thirty two contaminants wereanalyzed. The sediment quality index (SQI) was derived based on the contaminant data bycomparing with sediment quality guidelines (SQGs) established in Korea, Canada, andAutstraila/Newzealand (ANZECC). Toxic contaminants were found to be widely distributedacross the coast. Among the target compounds, PAHs showed the highest concentration,followed by butyltins, nonylphenols, PCBs, DDTs, HCHs and CHLs. Heavy metals werealso abundantly detected with the highest concentration of Zn followed by Cu > Cr > Pb> Ni > As> Cd > Hg. The sites located near Busan Harbor showed relatively higherconcentrations than those of Suyoung-Gu and Nakdong River. In general, theconcentrations of organic compounds and metals were highest at the inner part of harborareas with a tendency of declining from inside to outside, indicating a great loading ofpollutants from harbors. The high exceedance percentage (above 30% of the sites) forlow-SQGs were found for Zn, Cu, TBT, p,p’-DDT and p,p-DDD. The SQI scorescalculated from low-SQGs ranged from 18 to 100. Inner parts of Busan Harbor wasobserved as the regions of concern. Overall, TBT, Cu, p,p’-DDT, p,p’‘DDD, Zn, and somePAHs were the chemicals most frequently exceeding SQGs and influencing SQ the contaminant data bycomparing with sediment quality guidelines (SQGs) established in Korea, Canada, andAutstraila/Newzealand (ANZECC). Toxic contaminants were found to be widely distributedacross the coast. Among the target compounds, PAHs showed the highest concentration,followed by butyltins, nonylphenols, PCBs, DDTs, HCHs and CHLs. Heavy metals werealso abundantly detected with the highest concentration of Zn followed by Cu > Cr > Pb> Ni > As> Cd > Hg. The sites located near Busan Harbor showed relatively higherconcentrations than those of Suyoung-Gu and Nakdong River. In general, theconcentrations of organic compounds and metals were highest at the inner part of harborareas with a tendency of declining from inside to outside, indicating a great loading ofpollutants from harbors. The high exceedance percentage (above 30% of the sites) forlow-SQGs were found for Zn, Cu, TBT, p,p’-DDT and p,p-DDD. The SQI scorescalculated from low-SQGs ranged from 18 to 100. Inner parts of Busan Harbor wasobserved as the regions of concern. Overall, TBT, Cu, p,p’-DDT, p,p’‘DDD, Zn, and somePAHs were the chemicals most frequently exceeding SQGs and influencing SQ