Distribution of total mercury in the coastal sediments of South Korea

Abstract

Total mercury (THg) concentrations were determined in 364 surficial sediment samples of 22 coastal areas including major trade harbors in South Korea. The accumulation levels and potential environmental risk of THg were evaluated in study areas. Concentrations of THg were in the ranged of N.D-3.34 mg kg-1. The enrichment factors (EF) of THg normalized to crustal abundance were 44.7 in maximum and higher than 1.5 in 40% of total samples and average EF values were found to be greater than 5 in North Busan Port, South Busan Port and YonghoMan which have high shipping activities and urban waste water discharges. This indicates that the sediments of study areas were contaminated partially with THg by anthropogenic sources. Potential ecotoxicological effects by THg contamination were evaluated through the comparison with the sediment quality guidelines developed by US NOAA (Long et al. 1995). Among the total sediment samples, the percentage of sediment samples exceeding the effects-range-median (ERM) was 4.4% and 20.3% of the sediment samples were between the effects-range-low (ERL) and ERM values, and most sediment samples (75.3%) were below ERL values. Compared to each study area, the percentage of sediment samples exceeding ERMs was 55% of South Busan Port, 29% of North Busan Port and 20% of YonghoMan, respectively.No significant correlations were found between THg and organic matter and particle size, suggesting threas. Concentrations of THg were in the ranged of N.D-3.34 mg kg-1. The enrichment factors (EF) of THg normalized to crustal abundance were 44.7 in maximum and higher than 1.5 in 40% of total samples and average EF values were found to be greater than 5 in North Busan Port, South Busan Port and YonghoMan which have high shipping activities and urban waste water discharges. This indicates that the sediments of study areas were contaminated partially with THg by anthropogenic sources. Potential ecotoxicological effects by THg contamination were evaluated through the comparison with the sediment quality guidelines developed by US NOAA (Long et al. 1995). Among the total sediment samples, the percentage of sediment samples exceeding the effects-range-median (ERM) was 4.4% and 20.3% of the sediment samples were between the effects-range-low (ERL) and ERM values, and most sediment samples (75.3%) were below ERL values. Compared to each study area, the percentage of sediment samples exceeding ERMs was 55% of South Busan Port, 29% of North Busan Port and 20% of YonghoMan, respectively.No significant correlations were found between THg and organic matter and particle size, suggesting th