Using a choice experiment to measure the environmental costs of air pollution impacts in Seoul

Air pollution, a by-product of economic growth, has been incurring extensive environmental costs in Seoul, Korea. Unfortunately, air pollution impacts are not treated as a commercial item, and thus it is difficult to measure the environmental costs arising from air pollution. There is an imminent need to find a way to measure air pollution impacts so that appropriate actions can be taken to control air pollution. Therefore, this study attempts to apply a choice experiment to quantifying the environmental costs of four air pollution impacts (mortality, morbidity, soiling damage, and poor visibility), using a specific case study of Seoul. We consider the trade-offs between price and attributes of air pollution impacts for selecting a preferred alternative and derive the marginal willingness to pay (WTP) estimate for each attribute. According to the results, the households' monthly WTP for a 10% reduction in the concentrations of major pollutants in Seoul was found to be approximately 5494 Korean won (USD 4.6) and the total annual WTP for the entire population of Seoul was about 203.4 billion Korean won (USD 169.5 million). This study is expected to provide policy-makers with useful information for evaluating and planning environmental policies relating specifically to air pollution.     

Heavy metal contamination and metallothionein mRNA in blood and feathers of Black-tailed gulls (Larus crassirostris) from South Korea

The objectives of this study were to determine levels of heavy metal in the feathers and blood of Black-tailed gulls (Larus crassirostris), to evaluate metallothionein (MT) mRNA level in Black-tailed gulls on three independent islets, and to examine the correlation between heavy metal concentrations and MT mRNA expression. Eleven heavy metals (Al, Cd, Mn, Pb, Cr, Fe, Cu, Zn, Se, Hg, and As) were investigated in blood and feathers of 65 chicks from breeding colonies (Seomando, Hongdo, and Dokdo islet) of South Korea in 2010. Heavy metals were assayed by PerkinElmer NexION 300 inductively coupled plasma mass spectrometry. The mean concentrations of non-essential heavy metals were found to blood containing Cd (0.002?~?0.02 ppm), Pb (0.06?~?0.18) ppm, Hg (0.03?~?0.05) ppm, and As (0.26?~?0.48 ppm), and feather containing Cd (0.05?~?0.30 ppm), Pb (2.47?~?10.80 ppm), Hg (1.18?~?1.57 ppm), and As (0.15?~?0.44 ppm). Chicks on Seomando islet showed the highest levels of metals (Cd, Pb, Mn, Cr, Cu, and Se in blood; Al, As, Mn, Cr, Fe, Cu, and Se in feathers) among the colonies. Concentrations of Pb and Hg in feathers were the highest on Hongdo, and the levels of Cd and Zn in feathers were the highest on Dokdo islet. MT mRNA in the blood of Black-tailed gulls was relatively higher in gulls from Seomando than in gulls from Hongdo and Dokdo islet. MT mRNA level is thus positively correlated to heavy metal concentrations in Black-tailed gulls.     

Absorption behavior of chlorine and sulfur by Ca(OH)<Subscript>2</Subscript> under simulated conditions with a fluidized bed combustor

This study was carried out to investigate the absorption reaction of chlorine and sulfur with Ca(OH)₂ under simulated conditions related to the co-combustion of refuse-derived fuel and sewage sludge in the fluidized bed combustor, such as high temperature, moisture and a mixing of samples. The combustion experiments were carried out in an electrical furnace with PVC and sulfur powders as the waste samples. High-purity slaked lime powder was used to capture the chlorine and sulfur. The experimental results showed that the removal efficiencies of both chlorine and sulfur were over 90% when the mole ratios of Ca on Cl and S were over 2.5. Furthermore, simultaneous absorption was helpful in improving the removal efficiency of chlorine and sulfur. The presence of chlorine markedly increased the removal efficiency of sulfur. The removal efficiency of chlorine was the highest at 700°C in both independent and simultaneous absorption. The removal efficiency of sulfur increased as the temperature increased, but the removal efficiency of chlorine sharply decreased from 95 to 83% when the moisture content in gases increased from 0 to 20 vol%. These results were confirmed by the combustion test of granular CaCl₂.     

Detecting points as developmental delay based on the life-history development and urosome deformity of the harpacticoid copepod, Tigriopus japonicus sensu lato, following exposure to benzo(a)pyrene

To identify ecotoxicological responses to an endocrine disrupter, benzo(a)pyrene, we examined the life-history of the harpacticoid copepod, Tigriopus japonicus sensu lato. Based on the life-history of copepods, survival rate of nauplii (NSR) and copepodites (CSR), copepodite emergence day (CED) and adult male emergence day (AMED), sex ratio (MER), brooding success rate (BSR), and first brooding day of adult females (FBD) were measured. Significant differences were observed in the survival and development of nauplii (NSR and CED) and sex ratio (MER) of exposed and non-exposed copepods. Moreover, high concentration of BaP can be lethal to copepodite and exhibited a delay of growth. In this study, the CED and AMED among ecotoxicological response based on life-history developments were delayed and the body characteristics decreased in response to exposure to benzo(a)pyrene. The dwarfism and urosome deformity of the T. japonicus s.l. was exhibited in response to chemical exposure. Specifically, the body characteristics and biomass of dwarf copepods that had been exposed to benzo(a)pyrene were 30% and 50% lower than the control group, respectively. The incidence of abnormal urosomes was divided into two types. The first deformity type was signs of shrinkage in the middle of the urosome or the entire urosome was narrower than those of the control organisms. In the second type, the anal somite and the distal side of the urosome had abnormally swelled. Taken together, the nauplii and copepodid development of T. japonicus s.l. can be used as a useful biomaker for detecting developmental delay based on their entire life-history. In addition, the urosome deformity was used a good potential monitoring tool invading various chemicals and environmental contamination into water system.     

Development and implementation of surface water quality standards for protection of human health in Korea

Current water quality standards for the protection of human health in Korea include 17 substances found in rivers and streams. Due to increasing concern over the release of hazardous chemicals into the aquatic environment, there has been a demand for additional water quality standards. Therefore, the Korean Ministry of the Environment plans to gradually increase the number of water quality standards to 30 substances, including 22 substances for protection of human health and 8 substances for protection of aquatic ecosystems by 2015. In this study, new water quality standards for protection of human health were established for 1,4-dioxane, formaldehyde, and hexachlorobenzene. We selected candidate hazardous chemicals, conducted a human health risk assessment to determine priority chemicals, established water quality standards based on technical analyses and comparison with domestic and developed countries’ water quality standards, and conducted an expert review. Water quality standards for protection of aquatic ecosystems will be derived in the near future. This study describes how the water quality standards for protection of human health were developed and implemented. Current status, recent expansion, and future plans for water quality standards in Korea are also covered.