Publications by authors named "Sung-Deuk Choi"

83 Publications

Driving factors to air pollutant reductions during the implementation of intensive controlling policies in 2020 in Ulsan, South Korea.

Environ Pollut 2021 Oct 16;292(Pt B):118380. Epub 2021 Oct 16.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

Evaluation for the controlling policy's effectiveness to mitigate criteria air pollutants (CAPs) in South Korea during December 1, 2019-March 31, 2020 is difficult because of its coincidence with the COVID-19 social distancing. In this study, we differentiated the influence of three major driving factors (intensive controlling policy by the government, meteorological conditions, and social distancing) to the CAP variation in Ulsan, the largest industrial city in South Korea. In 2013-2019, the concentrations of PM (2015-2019), PM, SO, and NO decreased by 6.7, 1.6, 4.2, and 3.3%/year, respectively, whereas the O concentration slightly increased by 0.7%/year. Trend analysis was used to predict the CAP concentrations before (January 1-February 21) and during (February 22-March 31) the social distancing in 2020. The difference between the measured and predicted concentrations was designated as the contribution of the three factors. The controlling policy was the most important driver of the CAP reductions. In particular, its contributions were 94.1% (January 1-February 21) and 87.4% (February 22-March 31) to the PM decrease. The change in meteorological conditions considerably affected the CAP reductions, with the highest contributions of 35.2% (January 1-February 21) and 39.2% (February 22-March 31) to the O decrease. On February 22-March 31, the effects of social distancing were 1.6, 0.6, 1.3, and 1.4% to the reduction of SO, NO, PM, and PM, respectively. Overall, a decrease in the CAP concentrations was apparent during January-March 2020 in Ulsan primarily due to the intensive controlling policies, not by the COVID-19 social distancing.
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http://dx.doi.org/10.1016/j.envpol.2021.118380DOI Listing
October 2021

Health risk assessment of exposure to organochlorine pesticides in the general population in Seoul, Korea over 12 years: A cross-sectional epidemiological study.

J Hazard Mater 2021 Sep 30;424(Pt B):127381. Epub 2021 Sep 30.

Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea. Electronic address:

This study evaluated the 12-year trends in serum levels of 28 organochlorine pesticides (OCPs) in 880 adults living in Seoul, Korea. The OCP levels decreased from 2006 to 2017, and p,p'-dichlorodiphenyldichloroethylene was a predominant compound. OCP levels were higher in females than in males, and showed positive associations with BMI and age. The OCP concentrations had inverted U-shaped associations with low-density lipoprotein cholesterol and total cholesterol. Concentrations of β-hexachlorocyclohexane were significantly higher in patients with hypertension than in participants that were normotensive. OCP levels showed positive associations with uric acid, creatinine, and thyroid-stimulating hormone, but negative associations with free thyroxine. Participants with diabetes had significantly higher OCP levels than those without it. Principal component analysis suggested possible differences in disease manifestation depending on the composition of OCPs. These results suggest that OCPs might disturb renal transport and thyroid homeostasis. To our knowledge, the inverted U-shaped associations of heptachlor epoxide and endosulfan with cholesterol, the epidemiological associations of trans-nonachlor and endosulfan with thyroid hormones, and the association of p,p'-DDE with hyperuricemia have not been previously reported in general population. This is the first long-term study to show trends of 28 OCPs in serum and associations with various health indicators in Korea.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127381DOI Listing
September 2021

Source apportionment of PM and sulfate formation during the COVID-19 lockdown in a coastal city of southeast China.

Environ Pollut 2021 Oct 11;286:117577. Epub 2021 Jun 11.

Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China. Electronic address:

Revealing the changes in chemical compositions and sources of PM is important for understanding aerosol chemistry and emission control strategies. High time-resolved characterization of water-soluble inorganic ions, elements, organic carbon (OC), and elemental carbon (EC) in PM was conducted in a coastal city of southeast China during the COVID-19 pandemic. The results showed that the average concentration of PM during the city lockdown (CLD) decreased from 46.2 μg m to 24.4 μg m, lower than the same period in 2019 (PM: 37.1 μg m). Concentrations of other air pollutants, such as SO, NO, PM, OC, EC, and BC, were also decreased by 27.3%-67.8% during the CLD, whereas O increased by 28.1%. Although SO decreased from 4.94 μg mto 1.59 μg m during the CLD, the concentration of SO (6.63 μg m) was comparable to that (5.47 μg m) during the non-lockdown period, which were attributed to the increase (16.0%) of sulfate oxidation rate (SOR). O (O+NO) was positively correlated with SO, suggesting the impacts of photochemical oxidation. A good correlation (R = 0.557) of SO and Fe and Mn was found, indicating the transition-metal ion catalyzed oxidation. Based on positive matrix factorization (PMF) analysis, the contribution of secondary formation to PM increased during the epidemic period, consisting with the increase of secondary organic carbon (SOC), while other primary sources including traffic, dust, and industry significantly decreased by 9%, 8.5%, and 8%, respectively. This study highlighted the comprehensive and nonlinear response of chemical compositions and formation mechanisms of PM to anthropogenic emissions control under relatively clean conditions.
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http://dx.doi.org/10.1016/j.envpol.2021.117577DOI Listing
October 2021

Monitoring and risk assessment of arsenic species and metals in the Taehwa River in Ulsan, the largest industrial city in South Korea.

Mar Pollut Bull 2021 Aug 23;172:112862. Epub 2021 Aug 23.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea. Electronic address:

Toxic metals, As, and As species were monitored at 18 stations along the Taehwa River in Ulsan. The concentrations of Ni (98.4 μg/L) at stations near industrial areas were relatively high and exceeded the WHO's drinking water guidelines (70 μg/L) and the US EPA's national recommended water quality criteria (52 μg/L). Principal component analysis and cluster analysis revealed that Ni and Cu were more strongly influenced by industrial activity than other elements in the Taehwa River estuary. Analysis of the hazard quotient (HQ) and cancer risk (CR) indicated that As was of the greatest non-carcinogenic and carcinogenic concern. Notably, the HQ and CR of As at suburban stations exceeded 1 and 10, respectively, representing a significant health risk. These results indicate that As speciation testing is crucial for the development of effective management plans based on health risks because the toxicity and mobility of As depend on its chemical form.
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http://dx.doi.org/10.1016/j.marpolbul.2021.112862DOI Listing
August 2021

Spatial distribution and temporal variation of polycyclic aromatic hydrocarbons in runoff and surface water.

Sci Total Environ 2021 Nov 14;793:148339. Epub 2021 Jun 14.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.. Electronic address:

This study aims to investigate the spatial distribution of and temporal variation in the phase distribution, emission sources, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in runoff and in surface water mixed with runoff discharge. The samples were collected at semi-rural, residential, and industrial sites in Ulsan, South Korea, from April to October 2016. The industrial site had the highest PAH concentrations in the runoff and surface water due to the higher PAH levels found in the surrounding environmental media. The PAH phase distributions were relatively similar between the sampling sites, with dissolved PAHs (2- to 4-ring species) dominant. In July, the PAHs in the surface water were more commonly found in the dissolved phase due to the higher water temperature and dissolved organic carbon concentration. The emission sources for the PAHs were identified using principal component analysis (PCA), a dimension reduction technique, and the k-nearest neighbor (KNN) classifier, a supervised learning algorithm. It was determined that the PAHs in the runoff and surface water were likely to share similar petrogenic and pyrolysis sources for most of the sampling periods. The ecological risk of the surface water was 1.5-4.5 times lower after being mixed with runoff water, mainly due to dilution effects. The ecological risk for surface water was highest in July because of the higher PAH concentrations. This study contributes to the understanding of PAHs in runoff and in surface water affected by runoff discharge.
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http://dx.doi.org/10.1016/j.scitotenv.2021.148339DOI Listing
November 2021

Record of North American boreal forest fires in northwest Greenland snow.

Chemosphere 2021 Aug 6;276:130187. Epub 2021 Mar 6.

Analysis Service Center, Diatech Korea Co., Ltd., Seoul, 05808, Republic of Korea.

We present boreal forest fire proxies in a northwest Greenland snowpit spanning a period of six years, from spring 2003 to summer 2009. Levoglucosan (CHO) is a specific organic molecular marker of biomass burning caused by boreal forest fires. In this study, levoglucosan was determined via liquid chromatography/negative ion electrospray ionization-tandem mass spectrometry, wherein isotope-dilution and multiple reaction monitoring methods are employed. Ammonium (NH) and oxalate (CO), traditional biomass burning proxies, were determined using two-channel ion chromatography. In the northwest Greenland snowpit, peaks in levoglucosan, ammonium, and oxalate were observed in snow layers corresponding to the summer-fall seasons of 2004 and 2005. Considered together, these spikes are a marker for large boreal forest fires. The levoglucosan deposited in the Greenland snow was strongly dependent on long-range atmospheric transportation. A 10-day backward air mass trajectory analysis supports that the major contributors were air masses from North America. In addition, satellite-derived carbon monoxide (CO) and ammonia (NH) concentrations suggest that chemicals from North American boreal forest fires during the summer-fall of 2004 and 2005 were transported to Greenland. However, large boreal fires in Siberia in 2003 and 2008 were not recorded in the snowpit. The sub-annual resolution measurements of levoglucosan and ammonium can distinguish between the contributions of past boreal forest fires and soil emissions from anthropogenic activity to Greenland snow and ice.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130187DOI Listing
August 2021

Air pollution increases human health risks of PM-bound PAHs and nitro-PAHs in the Yangtze River Delta, China.

Sci Total Environ 2021 May 27;770:145402. Epub 2021 Jan 27.

Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address:

Identifying the nature and extent of atmospheric PM-bound toxic organic pollutants is beneficial to evaluate human health risks of air pollution. Seasonal observations of PM-bound polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs (NPAHs) in the Yangtze River Delta (YRD) were investigated, along with criteria air pollutants and meteorological parameters. With the elevated PM level, the percentage of 4-ring PAHs and typical NPAH including 3-Nitrobiphenyl (3-NBP) and 2-Nitrofluoranthene (2-NFLT) increased by 19-40%. PM-bound 2-NFLT was positively correlated with O and NO, suggesting the contribution of atmospheric oxidation capacity to enhance the secondary formation of NPAHs in the atmosphere. Positive matrix factorization (PMF) analysis indicated that traffic emissions (44.9-48.7%), coal and biomass combustion (27.6-36.0%) and natural gas and volatilization (15.3-27.5%) were major sources of PAHs, and secondary formation (39.8-53.8%) was a predominant contributor to total NPAH concentrations. Backward trajectory analysis showed that air masses from North China transported to the YRD region increased PAH and NPAH concentrations. Compare to clean days, the BaP equivalent concentrations of total PAHs and NPAHs during haze pollution days were enhanced by 10-25 and 2-6 times, respectively. The Incremental Lifetime Cancer Risks (ILCRs) of PAHs by inhalation exposure also indicated high potential health risks in the YRD region. The results implied that the health risks of PM-bound PAHs and NPAHs could be sharply enhanced with the increase of PM concentrations.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145402DOI Listing
May 2021

Seasonal variation and gas/particle partitioning of atmospheric halogenated polycyclic aromatic hydrocarbons and the effects of meteorological conditions in Ulsan, South Korea.

Environ Pollut 2020 Aug 22;263(Pt A):114592. Epub 2020 Apr 22.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

Atmospheric halogenated polycyclic aromatic hydrocarbons (Halo-PAHs) and parent PAHs were monitored in Ulsan, South Korea for one year (January‒December 2015) to investigate their seasonal patterns, gas/particle partitioning behavior, and the impact of meteorological conditions. The mean concentrations of 24 chlorinated PAHs, 11 brominated PAHs, and 13 parent PAHs in the gaseous and particulate phases were 8.64 and 9.64 pg/m, 11.6 and 1.62 pg/m, and 2.17 and 2.40 ng/m, respectively. Winter had the highest ClPAH and PAH levels, with significant contributions from poly-chlorine groups and high-molecular-weight compounds. However, BrPAHs showed reverse patterns with the highest concentration in summer and the dominant gaseous fraction throughout the year. This finding could be explained by the strong local sources of BrPAHs, related to automobile and petrochemical industries. In contrast, the effects of the temperature inversion layer and atmospheric transport from the outside of Ulsan were more apparent for ClPAHs and PAHs, particularly in winter and spring. Regarding gas/particle partitioning, Halo-PAHs exhibited different seasonal behaviors from those of parent PAHs. The sorption pathway of Halo-PAHs seemed to shift from absorption as the sole dominant mechanism in winter and spring to both adsorption and absorption in summer and fall, while both partitioning mechanisms contributed equally for parent PAHs during the entire year. This study implies that Halo-PAHs and parent PAHs might not share the same atmospheric behavior, possibly due to different characteristics in atmospheric reactions with other chemicals and particle-size distribution. However, there have been limited studies about the formation of Halo-PAHs and their physicochemical properties; hence, further in-depth investigations are of vital importance.
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http://dx.doi.org/10.1016/j.envpol.2020.114592DOI Listing
August 2020

Contamination characteristics of polychlorinated naphthalenes in the agricultural soil of two industrial cities in South Korea.

Chemosphere 2021 Jun 23;273:129721. Epub 2021 Jan 23.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

This study investigates the contamination characteristics of polychlorinated naphthalenes (PCNs) in the rice paddy soils of two industrial cities (Pohang and Ulsan) in South Korea. The paddy soils were collected from 40 sites in the paddy fields near industrial complexes in both cities. The mean concentration of Σ PCNs was 145.9 ± 101.7 pg/g and 95.4 ± 41.4 pg/g for the soils in Pohang and Ulsan, respectively. The toxic equivalents (TEQs) of Σ PCNs ranged from 0.007 pg-TEQ/g to 0.069 pg-TEQ/g in Pohang, and 0.015 pg-TEQ/g to 0.046 pg-TEQ/g in Ulsan. The PCN profiles were dominated by lower chlorinated homologues such as tetra- and tri-CNs for both cities, which are associated with the historical use of technical products, or more specifically, Halowaxes (HW 1099, 1031, 1013, and 1001). The results of the principal component analysis (PCA) indicate that the historical residues from the technical products contributed to the PCN contamination, but the influence of combustion sources was also observed with a high fraction of combustion-related congeners. Based on this study, we can expect that rice grown in these paddy fields will accumulate PCNs and other combustion-related pollutants, strongly suggesting the necessity for multimedia (e.g., air, soil, water, and rice) monitoring and human exposure assessments of PCNs.
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http://dx.doi.org/10.1016/j.chemosphere.2021.129721DOI Listing
June 2021

Per- and polyfluoroalkyl substances and their alternatives in black-tailed gull (Larus crassirostris) eggs from South Korea islands during 2012-2018.

J Hazard Mater 2021 06 6;411:125036. Epub 2021 Jan 6.

Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea. Electronic address:

The temporal and spatial trends of sixteen per- and polyfluoroalkyl substances (PFAS) and their three alternatives, chlorinated polyfluoroalkyl ether sulfonic acid (F-53B), hexafluoropropylene oxide dimer acid (GenX), and dodecafluoro-3H-4,8-dioxanonanoate (ADONA) in whole eggs of black-tailed gulls from two South Korean islands, Baengnyeongdo (BLD) and Hongdo (HD), were investigated during 2012-2018. A total of 16 analyzed compounds were detected at concentrations of 21.3-47.8 ng/g ww in BLD and 11.2-40.0 ng/g ww in HD. Meanwhile, the mean levels of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were detected at 6.92 ± 4.72 ng/g ww and 0.674 ± 0.993 ng/g ww, respectively. In particular, F-53B, a major alternative to PFOS was detected in each year of the study period with a level of up to 6.66 ng/g ww in all egg samples. Significant increasing temporal trends were observed for PFOS, perfluorononanoic acid (PFNA) and one alternative (F-53B) during the investigated period suggesting continuous use or accumulation of these in the Korean environment. Moreover, distinctive spatial distribution patterns such as a significantly higher F-53B level in HD and an increased PFAS (< C11) in BLD were also observed.
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http://dx.doi.org/10.1016/j.jhazmat.2020.125036DOI Listing
June 2021

Factors associated with partitioning behavior of persistent organic pollutants in a feto-maternal system: A multiple linear regression approach.

Chemosphere 2021 Jan 4;263:128247. Epub 2020 Sep 4.

Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Nam-gu, Pohang, 37673, Republic of Korea. Electronic address:

Prenatal exposure to persistent organic pollutants (POPs) has been a matter of particular concern because such exposure can severely affect the health of the fetus. The mechanistic understanding of the partitioning behavior of POPs in the feto-maternal system and the associated factors, however, have rarely been studied. Here, we employed a new approach based on multiple linear regression (MLR) analysis to predict the feto-maternal ratio (FM-ratio) of POPs and to assess the factors associated with feto-maternal partitioning behavior. Two preliminary exploratory MLR models were built using physiological conditions of the participants, and molecular descriptors were calculated with a computational model. The FM-ratio was calculated from the concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs) in 20 pairs of maternal and cord blood. The models showed that the lipids and cholesterols in the maternal and cord blood and the placenta significantly influence the partitioning of POPs. The body mass index (BMI) change during pregnancy was also related to the FM-ratio. The physicochemical properties associated with lipophilicity and molecular size were also related to the FM-ratio. Even though the results should be interpreted with caution, the preliminary MLR models illustrate that feto-maternal partitioning is governed by transplacental transporting mechanisms, toxicokinetics, and the molecular physicochemical properties of POPs. Overall, the new approach used in this study can improve our understanding of the partitioning behavior in the feto-maternal system.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128247DOI Listing
January 2021

Spatial distribution, source identification, and anthropogenic effects of brominated flame retardants in nationwide soil collected from South Korea.

Environ Pollut 2021 Mar 9;272:116026. Epub 2020 Nov 9.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

Soil samples were collected at 61 sites of the national monitoring network for persistent organic pollutants (POPs) in South Korea. The target compounds were brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), hexabromocyclododecanes (HBCDDs), and tetrabromobisphenol A (TBBPA). The mean concentrations of Σ PBDEs, Σ HBCDDs, and TBBPA in soil were 222, 17.2, and 4.4 ng/g, respectively, but PBBs were not detected. Industrial sites had statistically higher BFR concentrations than suburban sites but no significant difference compared with urban sites. The commercial deca-BDE mixtures were the most likely source of PBDE contamination in the soil samples, with the minor influence of commercial penta-BDE and octa-BDE mixtures. The profiles of HBCDDs in most soil samples differed from those in the powder types of technical HBCDD mixtures, indicating that they are affected by the HBCDDs contained in commercial products and the conversion of HBCDD diastereoisomers (γ-HBCDD to α-HBCDD) in the environment. The concentrations of Σ PBDEs, Σ HBCDDs, and TBBPA were significantly correlated with population density, gross domestic product, and the number of companies (p < 0.01), indicating a direct impact of anthropogenic activities. Significant correlations among BFRs were determined (0.63 < r < 0.74, p < 0.01), suggesting that these pollutants had similar sources. Relatively good correlations (0.44 < r < 0.98, p < 0.01) between BDE-209 and other light BDEs (except for BDE-71, -77, -126, -156, and -205) might result from the degradation of heavy BDEs under anaerobic and natural sunlight conditions. To the best of our knowledge, this study provides the most comprehensive soil monitoring data for various BFRs in South Korea. Furthermore, it is the first report on soil contamination by deca-BDE, HBCDDs, and TBBPA in South Korea.
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http://dx.doi.org/10.1016/j.envpol.2020.116026DOI Listing
March 2021

Contamination characteristics of polycyclic aromatic hydrocarbons in river and coastal sediments collected from the multi-industrial city of Ulsan, South Korea.

Mar Pollut Bull 2020 Nov 17;160:111666. Epub 2020 Sep 17.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea. Electronic address:

River and coastal sediments were collected at 17 stations in Ulsan, the largest industrial city in South Korea, to evaluate the levels, profiles, emission sources, and spatial distribution of polycyclic aromatic hydrocarbons (PAHs). The mean concentration of Σ PAHs was 722 ng/g, and fluoranthene was a predominant compound. PAHs with 4-6 rings showed higher proportions than PAHs with 2-3 rings. The stations located near industrial complexes showed elevated levels of indicator compounds for petroleum, coal, coke, and fuel combustion. Therefore, petrochemical industries, coal pier, non-ferrous industries, and vehicles were identified as the emission sources. As industrialization and urbanization progressed, an increase in PAH levels and profile changes were observed as a result of the increasing industrial fuel consumption and the increasing number of vehicles. This is the first study that confirmed the change of PAHs in sediment caused by the change of emission sources over time in Ulsan.
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http://dx.doi.org/10.1016/j.marpolbul.2020.111666DOI Listing
November 2020

Effects of the COVID-19 lockdown on criteria air pollutants in the city of Daegu, the epicenter of South Korea's outbreak.

Environ Sci Pollut Res Int 2020 Dec 28;27(36):45983-45991. Epub 2020 Oct 28.

Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.

The outbreak of COVID-19 in Daegu, South Korea, early in 2020 has led this metropolitan city to become one of the major hotspots in the world. This study investigates the association of meteorology and the new daily COVID-19 confirmed cases and the effects of the city lockdown on the variation in criteria air pollutants (CAPs) in Daegu. Ambient temperature and relative humidity were negatively correlated to the new daily cases and played an important role in the spread of COVID-19. Wind speed could enhance the virus transmission through the inhalation of aerosols and/or droplets and contact with fomites. The lockdown has directly decreased the concentrations of CAPs. In particular, reductions of 3.75% (PM), 30.9% (PM), 36.7% (NO), 43.7% (CO), and 21.3% (SO) between the period before and during the outbreak were observed over the entire city. An increase in O (71.1%) was affected by natural processes and photochemical formation other than the lockdown effects. The three central districts were the areas most affected by the virus and showed the highest reductions in CAPs (except for O) during the outbreak. Apart from the influence of the lockdown, the decreasing trend in CAPs may be a result of the actions taken by the government to mitigate air pollutants nationwide since 2019. The results of this study can be useful for government and medical organizations to understand the behavior of the virus in the atmosphere. Further studies are necessary to explore the detailed influences of the lockdown on the environment and public life.
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http://dx.doi.org/10.1007/s11356-020-11360-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7592145PMC
December 2020

Twenty-year trends and exposure assessment of polychlorinated dibenzodioxins and dibenzofurans in human serum from the Seoul citizens.

Chemosphere 2021 Jun 7;273:128558. Epub 2020 Oct 7.

Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea; National Institute of Environmental Research, Hwangyong-ro 42, Seo-gu, Incheon, 22689, Republic of Korea. Electronic address:

This study investigated polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in air (n = 108) and human serum (n = 1802) samples collected over 20 years to evaluate the long-term exposure to PCDD/Fs and health effects on the Korean general population. The serum PCDD/F levels were higher in males than in females and were significantly correlated with age, body mass index, and manifestation of diabetes mellitus. From 2000 to 2019, the PCDD/F levels declined by 96% in the air, but only by 36% in the serum, because PCDD/Fs are relatively stable in the human body and are exposed to humans after PCDD/Fs are distributed and migrated in various environmental matrices. The PCDD/F levels in other environmental matrices have also decreased at rates that differed among the matrices due to the different retention times and changes in continuous input of contaminants. As PCDD/Fs migrate from environmental matrices to the human body, the fraction of PCDDs increased whereas that of PCDFs decreased because of their relatively short half-lives. This study provides a concrete evidence that PCDD/F emissions by national regulations can achieve long-term reduction in human exposure. To the best of our knowledge, this is the longest and largest study to evaluate the long-term trends and annual changes of PCDD/Fs in the atmosphere and human serum, simultaneously.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128558DOI Listing
June 2021

Long-term nationwide assessment of polychlorinated dibenzo-p-dioxins/dibenzofurans and dioxin-like polychlorinated biphenyls ambient air concentrations for ten years in South Korea.

Chemosphere 2021 Jan 13;263:127903. Epub 2020 Aug 13.

Department of Environment Engineering, Inha University, Incheon, 22212, Republic of Korea. Electronic address:

In this study, seasonal/regional variations of Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and dioxin like-polychlorinated biphenyls in the ambient air were monitored for ten years (2008-2017) using a high volume air sampler. As a result of strict regulation enforced by Korea Ministry of Environment in 2008, PCDD/DFs concentrations in the ambient air decreased from 0.051 pg I-TEQ Sm in 2009 to 0.014 pg I-TEQ Sm in 2017 which was comparably associated with cut-down of their emission sources from 880.2 g I-TEQ Sm in 2001 to 24.2 g I-TEQ Sm in 2015; revealing that it was only 2.7% against that of 2001. In 2017, mean TEQ concentration level of PCDD/DFs in the air of South Korea was quite low in comparison to its ambient environmental standards of 0.6 pg I-TEQ Sm for PCDD/DFs. Particularly, the sum of PCDD/DFs in the background revealed the lowest level, however, the fraction of octachlorodibenzodioxin among other isomers exposed at the highest level in this study, suggesting that the ambient air quality in the background being studied was severely and persistently impaired by inflowing unknown sources of any possible anthropogenic transboundary migratory air pollutants. Moreover, this study conducted the scientific analysis of the long-term variations in the ambient air and emission sources using principal component analysis. From this of 10 years long-term nationwide assessments for the PCDD/DFs and dl-PCBs in the ambient air, it is possible to prove that South Korean environmental policy to manage POPs has been successfully conducted for the last ten years.
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http://dx.doi.org/10.1016/j.chemosphere.2020.127903DOI Listing
January 2021

Nationwide levels and distribution of endosulfan in air, soil, water, and sediment in South Korea.

Environ Pollut 2020 Oct 23;265(Pt B):115035. Epub 2020 Jun 23.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

We investigated the levels and distribution patterns of α- and β-endosulfan and endosulfan sulfate in air, soil, water, and sediment samples collected from the South Korean persistent organic pollutants (POPs) monitoring networks. In the air samples, the highest concentrations of the total (Σ) endosulfan (50.3-611 pg/m, mean: 274 pg/m) were observed during summer. Spearman analysis revealed a good correlation between agricultural land area and atmospheric concentrations of Σ endosulfan except during winter. Regardless of the season, the ratio of the two isomers (α/β) was 3.6-4.9 in the air samples, higher than that observed in technical mixtures (2.0-2.3), possibly due to the higher volatility of α-endosulfan, compared to β-endosulfan. Concentrations of Σ endosulfan in the soil samples (n.d.-13.4 ng/g, mean: 0.8 ng/g) were not significantly different except at some stations adjacent to large areas of farmland. The average levels of Σ endosulfan in the water and sediment samples were 2.1 ng/L and 0.1 ng/g dw, respectively. In analyzing the four largest rivers, it was observed that a few water stations during spring and fall and sediment stations in fall had high concentrations of the two isomers and endosulfan sulfate, particularly around the Yeoungsan and Nakdong Rivers near large areas of agricultural land. Endosulfan sulfate was dominant at most water and sediment sampling stations. This study demonstrates that the endosulfan found in most environmental compartments most probably derives from agricultural areas despite its ban as a pesticide. On the other hand, given that it was also detected in industrial and urban areas, in which pesticide application does not occur, it can be conjectured that endosulfan is aerially transported at higher temperatures and continuously circulates within the environment.
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http://dx.doi.org/10.1016/j.envpol.2020.115035DOI Listing
October 2020

Acute toxicities of fluorene, fluorene-1-carboxylic acid, and fluorene-9-carboxylic acid on zebrafish embryos (Danio rerio): Molecular mechanisms of developmental toxicities of fluorene-1-carboxylic acid.

Chemosphere 2020 Dec 11;260:127622. Epub 2020 Jul 11.

School of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea. Electronic address:

In this study, fluorene (FL), FL-1-carboxylic acid (FC-1), and FL-9-carboxylic acid (FC-9) were investigated to understand their acute toxicity by measuring inhibitory effects on hatching rates and developmental processes of zebrafish embryos (Danio rerio). For exposure concentrations up to 3000 μg/L, FC-1 alone showed acute toxicity at 1458 μg/L for LC value. FC-1 caused yolk sac and spinal deformities, and pericardial edema. Molecular studies were undertaken to understand FC-1 toxicity examining 61 genes after exposure to 5 μM (equivalent to LC value of FC-1) in embryos. In the FC-1-treated embryos, the expression of the cyp7a1 gene, involved in bile acid biosynthesis, was dramatically decreased, while the expression of the Il-1β gene involved in inflammation was remarkably increased. In addition to these findings, in FC-1-treated embryos, the expression of nppa gene related to the differentiation of the myocardium was 3-fold increased. On the other hand, cyp1a, cyp3a, ugt1a1, abcc4, mdr1, and sult1st1 responsible for detoxification of xenobiotics were upregulated in FC-9-treated embryos. Taken together, carboxylation on carbon 1 of FL increased acute toxicity in zebrafish embryos, and its toxicity might be related to morphological changes with modification of normal biological functions and lowered defense ability.
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http://dx.doi.org/10.1016/j.chemosphere.2020.127622DOI Listing
December 2020

Spatially high-resolved monitoring and risk assessment of polycyclic aromatic hydrocarbons in an industrial city.

J Hazard Mater 2020 07 25;393:122409. Epub 2020 Feb 25.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea. Electronic address:

Polycyclic aromatic hydrocarbons (PAHs) were monitored at 20 sites in semi-rural, urban, and industrial areas of Ulsan, the largest industrial city in South Korea, for one year. The target compounds were the 16 priority PAHs designated by the US Environmental Protection Agency except for naphthalene, acenaphthene, and acenaphthylene. Gaseous PAHs collected using polyurethane foam-based passive air samplers (PUF-PASs) and particulate PAHs predicted using gas/particle partitioning models were used to estimate the human health risks. The mean total cancer risk through inhalation intake and dermal absorption for all target age groups (children, adolescents, adults, and lifetime) ranged from 0.10 × 10 to 2.62 × 10, lower than the acceptable risk level (10), thus representing a safe level for residents. The cancer risk through dermal absorption and inhalation intake was predicted to be highest in winter, mostly due to the higher concentrations of PAHs, especially high-molecular-weight species with greater toxicity. Additionally, gaseous and particulate PAHs contributed more to dermal absorption and inhalation intake, respectively. As a consequence of local emissions and advection, the risks were higher in the industrial and semi-rural areas. This study suggests that human health risks can be cost-effectively mapped on a local scale using passive air sampling.
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http://dx.doi.org/10.1016/j.jhazmat.2020.122409DOI Listing
July 2020

Passive air sampling of halogenated polycyclic aromatic hydrocarbons in the largest industrial city in Korea: Spatial distributions and source identification.

J Hazard Mater 2020 01 17;382:121238. Epub 2019 Sep 17.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

Some halogenated polycyclic aromatic hydrocarbons (Halo-PAHs) are known to be more toxic than their corresponding parent PAHs, but studies on Halo-PAHs have been somewhat limited. In this study, passive air samplers were used to monitor Halo-PAH and PAH contamination at 20 sampling sites in Ulsan, one of the largest industrial cities in South Korea. The mean concentrations of Σ ClPAHs, Σ BrPAHs, and Σ PAHs were 207 pg/m, 84 pg/m, and 26 ng/m, respectively. Industrial areas displayed higher concentrations of both Halo-PAHs and PAHs than urban and rural areas. Strong correlations between energetically unfavorable Halo-PAHs and their corresponding parent PAHs suggest that the main formation mechanism of Halo-PAHs is not direct halogenation of PAHs. Low molecular weight Halo-PAHs with one halogen atom and their parent PAHs were dominant. The profiles of ClPAHs and BrPAHs in petrochemical, automobile, shipbuilding, and non-ferrous industrial complexes were distinguished. The toxicity equivalency quantities (TEQs) of ClPAHs, BrPAHs, and PAHs at the industrial sites also showed the highest values of 4.2, 0.5, and 18.3 pg-TEQ/m, respectively, reflecting the high toxicity of Halo-PAHs. To the best of our knowledge, this is the first study reporting atmospheric levels of both ClPAHs and BrPAHs using passive air samplers.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121238DOI Listing
January 2020

An improved rapid analytical method for the arsenic speciation analysis of marine environmental samples using high-performance liquid chromatography/inductively coupled plasma mass spectrometry.

Environ Monit Assess 2019 Jul 30;191(8):525. Epub 2019 Jul 30.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.

Arsenic contamination in marine environments is a serious issue because some arsenicals are very toxic, increasing the health risks associated with the consumption of marine products. This study describes the development of an improved rapid method for the quantification of arsenic species, including arsenite (As), arsenate (As), arsenocholine (AsC), arsenobetaine (AsB), dimethylarsinic acid (DMA), and monomethyl arsonic acid (MMA), in seaweed, sediment, and seawater samples using high-performance liquid chromatography/inductively coupled plasma-mass spectrometry (HPLC/ICP-MS). ICP-MS based on dynamic reaction cells was used to eliminate spectral interference. Ammonium nitrate- and phosphate-based eluents were used as the mobile phases for HPLC analysis, leading to shorter overall retention time (6 min) and improved peak separation. Arsenicals were extracted with a 1% HNO solution that required no clean-up process and exhibited reasonable sensitivity and peak resolution. The optimized method was verified by applying it to hijiki seaweed certified reference material (CRM, NMIJ 7405-a) and to spiked blank samples of sediment and seawater. The proposed method measured the concentration of As in the CRM as 9.6 ± 0.6 μg/kg dry weight (dw), which is close to the certified concentration (10.1 ± 0.5 μg/kg dw). The recovery of the six arsenicals was 87-113% for the sediment and 99-101% for the seawater. In the analysis of real samples, As was the most abundant arsenical in hijiki and gulfweed, whereas AsB was dominant in other seaweed species. The two inorganic arsenicals (As and As) and As were the most dominant in the sediment and seawater samples, respectively.
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http://dx.doi.org/10.1007/s10661-019-7675-xDOI Listing
July 2019

Contamination characteristics of siloxanes in coastal sediment collected from industrialized bays in South Korea.

Ecotoxicol Environ Saf 2019 Oct 23;182:109457. Epub 2019 Jul 23.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

Siloxanes have been used as chemical additives in various products since the 1940s. They are known to have potentially toxic effects, to be environmentally persistent, and to be bioaccumulative. Previous studies have reported high levels of siloxanes in various environmental matrices. In this study, 6 cyclic siloxanes (D4-D9) and 13 linear siloxanes (L3-L15) in coastal sediment collected from southeastern bays adjacent to industrial zones in South Korea (Busan, Ulsan, Jinhae, and Gwangyang) were analyzed. The contamination levels and spatial distribution of siloxanes in the coastal sediment samples were investigated, with the hazard quotients (HQs) for siloxanes evaluated using Monte Carlo simulation. Across all samples, the total concentration (Σ) of siloxanes was in the range of 11.6-3877 (mean: 305; median: 133) ng/g dry weight (dw). The highest average concentration of Σ siloxanes was found in Busan (mean: 580; median: 233 ng/g dw), followed by Ulsan (mean: 316; median: 209 ng/g dw), Jinhae (mean: 266; median: 125 ng/g dw), and Gwangyang (mean: 33; median: 27 ng/g dw), all of which are suggested to be affected by both industrial and domestic activities. The highest contributions were from D5 (18%) and D6 (34%), followed by D9 (7.3%) and L11 (5.8%). The HQs for siloxanes were less than 1, indicating that there was no risk to benthic organisms in the study areas; however, further monitoring of various environmental matrices is required to fully assess the potential ecological risks.
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http://dx.doi.org/10.1016/j.ecoenv.2019.109457DOI Listing
October 2019

Titanium dioxide nanoparticles oral exposure to pregnant rats and its distribution.

Part Fibre Toxicol 2019 07 18;16(1):31. Epub 2019 Jul 18.

Developmental and Reproductive Toxicology Research Group, Korea Institute of Toxicology, Deajeon, 34114, Republic of Korea.

Background: Titanium dioxide (TiO) nanoparticles are among the most manufactured nanomaterials in the industry, and are used in food products, toothpastes, cosmetics and paints. Pregnant women as well as their conceptuses may be exposed to TiO nanoparticles; however, the potential effects of these nanoparticles during pregnancy are controversial, and their internal distribution has not been investigated. Therefore, in this study, we investigated the potential effects of oral exposure to TiO nanoparticles and their distribution during pregnancy. TiO nanoparticles were orally administered to pregnant Sprague-Dawley rats (12 females per group) from gestation days (GDs) 6 to 19 at dosage levels of 0, 100, 300 and 1000 mg/kg/day, and then cesarean sections were conducted on GD 20.

Results: In the maternal and embryo-fetal examinations, there were no marked toxicities in terms of general clinical signs, body weight, food consumption, organ weights, macroscopic findings, cesarean section parameters and fetal morphological examinations. In the distribution analysis, titanium contents were increased in the maternal liver, maternal brain and placenta after exposure to high doses of TiO nanoparticles.

Conclusion: Oral exposure to TiO during pregnancy increased the titanium concentrations in the maternal liver, maternal brain and placenta, but these levels did not induce marked toxicities in maternal animals or affect embryo-fetal development. These results could be used to evaluate the human risk assessment of TiO nanoparticle oral exposure during pregnancy, and additional comprehensive toxicity studies are deemed necessary considering the possibility of complex exposure scenarios and the various sizes of TiO nanoparticles.
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http://dx.doi.org/10.1186/s12989-019-0313-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6639912PMC
July 2019

Distribution and diastereoisomeric profiles of hexabromocyclododecanes in air, water, soil, and sediment samples in South Korea: Application of an optimized analytical method.

Ecotoxicol Environ Saf 2019 Oct 13;181:321-329. Epub 2019 Jun 13.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:

In this study, the levels and distribution patterns of HBCD diastereoisomers in air, water, soil, and sediment samples in South Korea were investigated after optimizing the UPLC-MS/MS analytical process. Extraction and cleanup efficiencies were tested using several different extraction solvents and adsorbents. Dichloromethane was selected as the base extraction solvent, and multi-layer silica gel (MSG) and MSG-alumina columns were selected for the removal of HBCDs from complex environmental matrices. The concentration of Ʃ HBCDs was 22-133 pg/m, 10-128 ng/g, 0.2-151 ng/L, and 0.5-552 ng/g dw for air, soil, water, and sediment samples, respectively. Relatively higher concentrations of Ʃ HBCDs were observed at stations adjacent to industrial facilities (e.g., rubber and plastic, textile, chemical, fabricated metal, and wholesale trade factories) associated with the use of commercial HBCDs. The proportion of γ-HBCD in the soil (48.3-86.2%) and sediment (54.2-78.1%, except for one station) samples was similar to that found in technical and commercial HBCDs. In contrast, α-HBCD (52.3-71.2%) was dominant in all air samples, while the water samples displayed no clear trend in their diastereoisomer profiles. As the first nationwide report on HBCD diastereoisomers in the environment, this study demonstrates that most environmental compartments in South Korea are moderately contaminated with HBCDs.
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http://dx.doi.org/10.1016/j.ecoenv.2019.06.015DOI Listing
October 2019

Characteristics of metal contamination in paddy soils from three industrial cities in South Korea.

Environ Geochem Health 2019 Oct 23;41(5):1895-1907. Epub 2019 Jan 23.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.

Paddy soil contamination is directly linked to human dietary exposure to toxic chemicals via crop consumption. In Korea, rice paddy fields are often located around industrial complexes, a major anthropogenic source of metals. In this study, rice paddy soils were collected from 50 sites in three industrial cities to investigate the contamination characteristics and ecological risk of metals in the soils. The cities studied and their major industries are as follows: Ulsan (petrochemical, nonferrous, automobile, and shipbuilding), Pohang (iron and steel), and Gwangyang (iron and steel, nonmetallic, and petrochemical). Thirteen metals (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn) were analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES). The mean concentration of Cd (1.98 mg/kg) exceeded the soil quality guideline of Canada (1.4 mg/kg), whereas concentrations of other metals were under the standards of both Korea and Canada. Generally, levels of metal concentrations decreased with increasing distance from industrial complexes. Among the three cities, Pohang showed high concentrations of Zn (142.2 mg/kg), and Ulsan and Gwangyang showed high concentrations of Cr (33.9 mg/kg) and Ba (126.4 mg/kg), respectively. These contamination patterns were influenced by the different major industries of each city, which was clearly demonstrated by the principal component analysis results. Pollution indices suggested that As, Cd, Pb, and Zn were enriched in the paddy soils via anthropogenic activities. Comprehensive potential ecological risk indices were at considerable levels for most sites, especially because of major contributions from As and Cd, which can pose potential ecological threats.
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http://dx.doi.org/10.1007/s10653-019-00246-1DOI Listing
October 2019

Impact of traffic volumes on levels, patterns, and toxicity of polycyclic aromatic hydrocarbons in roadside soils.

Environ Sci Process Impacts 2019 Jan;21(1):174-182

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.

Vehicular exhaust is one of the important sources of polycyclic aromatic hydrocarbons (PAHs) in urban areas, and roadside soils can be directly contaminated with PAHs released from traffic emissions. In this study, roadside soils were collected at 10 sites in Ulsan, the largest industrial city in South Korea, to investigate the relationship between the traffic volume and the contamination characteristics of PAHs. The total concentrations of 16 US EPA priority PAHs (∑16 PAHs, mean: 1079 ng g-1) and organic-matter-normalized ∑16 PAHs (mean: 224 ng g-1 OM) were positively correlated with traffic volumes (Pearson correlation, r = 0.88 and 0.78, p < 0.01). The levels of carcinogenic PAHs were significantly higher at the high traffic sites than at the low traffic sites. High traffic sites (>25 000 vehicles per day) located at intersections showed elevated concentrations of indicator compounds (e.g., phenanthrene, fluoranthene, pyrene, and benzo[ghi]perylene) for gasoline and diesel exhaust. The diagnostic ratios also suggested a strong influence of the traffic emissions on the roadside soils, not only at urban sites but also at rural ones. Consequently, roadside soils and road dust (which are expected to be much more contaminated with PAHs than roadside soil) can act as important non-point sources of air and water pollution. The cancer risk from exposure to PAHs in the roadside soils was in an acceptable range, but continuous monitoring is required to evaluate the influence of increasing traffic on the environment and human health.
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http://dx.doi.org/10.1039/c8em00532jDOI Listing
January 2019

Spatial and temporal variations of volatile organic compounds using passive air samplers in the multi-industrial city of Ulsan, Korea.

Environ Sci Pollut Res Int 2019 Feb 6;26(6):5831-5841. Epub 2019 Jan 6.

School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.

The source-receptor relationship of volatile organic compounds (VOCs) is an important environmental concern, particularly in large industrial cities; however, only a few studies have identified VOC sources using high spatial resolution data. In this study, 28 VOCs were monitored in Ulsan, the biggest multi-industrial city in Korea. Passive air samplers were seasonally deployed at eight urban and six industrial sites. The target compounds were detected at all sites. No significant seasonal variations of VOCs were observed probably due to the continuous emissions from major industrial facilities. Benzene, toluene, ethylbenzene, xylenes, and styrene accounted for 66-86% of the concentration of Σ VOCs. The spatial distribution of the individual VOCs clearly indicated that petrochemical, automobile, non-ferrous, and shipbuilding industries were major VOC sources. Seasonal wind patterns were found to play a role in the spatial distribution of VOCs. Diagnostic ratios also confirmed that the industrial complexes were the dominant VOC sources. The results of principal component analysis and correlation analyses identified the influence of specific compounds from each industrial complex on individual sites. To the best of our knowledge, this is the first comprehensive report on the seasonal distribution of VOCs with high spatial resolution in a metropolitan industrial city in Korea.
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http://dx.doi.org/10.1007/s11356-018-4032-5DOI Listing
February 2019

Matrix-specific distribution and compositional profiles of perfluoroalkyl substances (PFASs) in multimedia environments.

J Hazard Mater 2019 02 5;364:19-27. Epub 2018 Oct 5.

Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, Pohang, 37673, Republic of Korea. Electronic address:

This study investigated perfluoroalkyl substances (PFASs) in multimedia environments to confirm the effects of emission sources of PFASs and to elucidate their spatial distribution. The highest PFAS levels were detected from the samples of air (272.30 pg/m) and surface water (36.54 ng/L) in an industrial complex area, meanwhile high PFAS levels were found from the samples of soil (8.80 ng/g) and sediment (84.98 ng/g) in urban areas and near wastewater treatment plants (WWTPs). Perfluorobutane sulfonate (PFBS) was primarily detected in water, influent and effluent, whereas long chain perfluorocarboxylic acids (PFCAs) and perfluorooctane sulfonate (PFOS) were dominant in dust, soil, sediment and sludge. While PFBS and neutral PFASs were dominant in air, PFCAs were primarily detected in plant and fish. The specific distribution patterns of PFASs in each matrix showed the influences of surrounding environments and different physicochemical characteristics of each congener. These findings suggest that the industrial complex and WWTP might be major emission sources to air and aquatic environments, respectively. This is the first study in which 6 neutral and 13 ionic PFASs were investigated simultaneously for nine different matrices in multimedia environments, and also it would be a good model study for future assessment of PFASs.
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http://dx.doi.org/10.1016/j.jhazmat.2018.10.012DOI Listing
February 2019

Levels of polybrominated diphenyl ethers in the Korean metropolitan population are declining: A trend from 2001 to 2013.

Environ Toxicol Chem 2018 09 6;37(9):2323-2330. Epub 2018 Aug 6.

School of Environmental Science and Engineering, Pohang University of Science and Technology, Nam-gu, Pohang, Kyungbuk, Republic of Korea.

Polybrominated diphenyl ethers (PBDEs) have been banned or voluntarily withdrawn from commerce worldwide. Declining levels of PBDEs in humans have been reported elsewhere, but not in Korea. We monitored 7 individual PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, and BDE-183) in 103 human serum samples collected in 2006. The arithmetic mean and median values for the sum of the 7 PBDEs (∑PBDEs) were 7.13 and 6.70 ng/g lipid, respectively. In addition, 6 pooled human serum samples collected in 2006, 2007, 2009, 2011, 2012, and 2013 were analyzed. A decrease in PBDE levels was observed, as reflected by the median value of ∑PBDEs from 5.98 in 2006 to 2.98 ng/g lipid in 2013 as well as in the pooled samples. The levels of individual congeners also decreased but at different declining rates. Based on these results and previously reported data, a definite decline in PBDE levels in the Korean metropolitan population could be observed from 2001 to 2013, providing the first evidence in Korea of the same decline observed elsewhere in the world. Environ Toxicol Chem 2018;37:2323-2330. © 2018 SETAC.
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http://dx.doi.org/10.1002/etc.4222DOI Listing
September 2018

HBCD and TBBPA in human scalp hair: Evidence of internal exposure.

Chemosphere 2018 Sep 7;207:70-77. Epub 2018 May 7.

Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Republic of Korea. Electronic address:

Human biomonitoring is a reliable method for evaluating human exposure to specific contaminants. Although blood is an ideal matrix for monitoring purposes, it is regarded as an invasive matrix. Therefore, current developments in the field of human biomonitoring are based on introducing new methods that use non-invasive matrices, such as hair. In this study, we examined the efficiencies of several extraction methods for the analysis of hexabromocyclododecane (HBCD) and tetrabromobisphenol-A (TBBPA) in human hair. The selected pretreatment method was validated through a general QA/QC process that included spiking experiments, and then, the method was used for the determination of HBCD and TBBPA concentrations in scalp hair samples collected from individuals in Korea (n = 24) and Iran (n = 15). The HBCD and TBBPA concentrations in the collected hair samples ranged from ND to 3.24 ng g and ND to 16.04 ng g, respectively. Significantly higher concentrations of TBBPA were found in hair samples from Korea than those in hair samples from Iran (p < 0.05), which is expected to be the result of the large market and higher exposure of TBBPA in Korea. HBCD was not detected in hair samples from Iran. According to our knowledge this is the first study demonstrating the presence of TBBPA in human hair with nonspecific exposure. Lastly, we investigated the important factors that influence the interpretation of the contributions of endogenous and exogenous contaminations in hair. Based on the information, the HBCD and TBBPA in the collected hair samples were most likely from endogenous exposure. Therefore, our study showed that hair is potentially a suitable indicator for the monitoring of internal exposure to HBCD and TBBPA in different populations.
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http://dx.doi.org/10.1016/j.chemosphere.2018.05.032DOI Listing
September 2018
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