• 한국환경과학회지
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• 제31권6호
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• pp.491-501
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• 2022

This study evaluated the contamination levels of inland pollution sources flowing into Taeanhaean National Park. The nutritional status of influents was assessed by analyzing water quality and trophic status index (TRIX) at 52 stations, and the contamination levels of sediments were evaluated by analyzing eutrophication cleanup index (CIET) and heavy metals at 36 stations. The results of the TRIX analysis showed that 26 of the 52 stations had influents with a TRIX value of 6-10 (poor water quality/very high trophic level), indicating atrocious water quality and high eutrophication levels. The results of the CIET analysis showed that 4 out of the 36 stations were highly contaminated with organic matter. Analysis of heavy metals showed that the copper (Cu) and zinc (Zn) levels exceeded the threshold effects level (TEL) and probable effects levels (PEL) at several stations. In addition, the arsenic (As) level exceeded the threshold effects level at one station, and the levels of the other heavy metals (Cd, Cr⁶⁺, Ni, Pb, and Hg) were lower. Most inland pollution sources have been identified as small-scale, but long-term and continuous exposure can negatively affect the marine ecosystem; therefore, it necessary to prepare inland pollution source management standards and measures suitable for the characteristics of the coastal area.

• 한국환경보건학회지
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• 제41권5호
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• pp.349-357
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• 2015

Objectives: The 2007 Korea National Survey for Environmental Pollutants in the Human Body found the highest blood mercury levels nationwide among residents in Seoksan-ri, Goro-myeon, Gunwi-gun, Gyeonsangbuk-do. With the aim to reduce the blood mercury levels of residents in this region, we conducted this study to identify the association between mercury exposure levels and shark meat consumption. Methods: This survey was conducted with 118 participants in Seoksan-ri before the Chuseok festival and 113 residents were added afterwards. Information on participants was collected via questionnaires. Total mercury concentrations in biological samples were measured using a mercury analyzer with the gold-amalgam collection method. Results: To identify this, we conducted mercury exposure level analysis before and after the Chuseok festival and found that blood and urinary mercury levels after Chuseok (GM of $6.9{\mu}g/L$ in blood and $1.68{\mu}g/g$_cr in urine) were higher than those before (GM of $5.29{\mu}g/L$ in blood and $1.44{\mu}g/g$_cr in urine). This area maintains a custom of using shark meat as one of the ancestral rite foods, and the performance of such rites and shark meat consumption have been identified as main sources of mercury exposure. Other than this, smoking, dental amalgam treatment and residential period in the area also contributed to an increase in mercury exposure levels. On the other hand, recent consumption of oriental medicine and vaccination did not have a significant influence on mercury levels. Conclusion: The results were attributed to the local custom of consuming shark meat with high mercury concentrations during rituals taking place during the festival and ancestral rites. Given that the blood mercury levels in 23.2% of the residents exceeded the HBM II values recommended by the German Commission on Human Biological Monitoring, it is suggested that further appropriate actions and follow-up measures be taken to reduce the mercury exposure levels of the residents that exceeded the reference values.

• 한국환경보건학회지
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• 제40권4호
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• pp.279-293
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• 2014

Objectives: Children are more susceptible to heavy metal toxicity than adults. The purpose of this study was to evaluate heavy metal concentrations in the blood of Korean preschoolers and investigate the association between metals in blood and related factors. Methods: A total of 512 subjects from 36 to 83 months of age were sampled. A questionnaire survey was performed and the levels of lead, mercury and cadmium were measured in the blood samples of all subjects. Their parents were interviewed in order to obtain information on basic characteristics, dietary patterns, socio-economic factors, and indoor/outdoor environment of the preschoolers. Multiple linear regression was used to analyze the association between the above factors and lead, mercury or cadmium concentrations. Results: The geometric mean concentrations of lead, mercury and cadmium in the blood were $1.45{\pm}1.58{\mu}g/dL$, $2.14{\pm}1.74{\mu}g/dL$ and $0.23{\pm}1.91{\mu}g/dL$, respectively. Results from multiple linear regression analysis showed that blood lead levels were associated with birth weight and paternal smoking status. Daily mercury intake from food and maternal education were also shown to influence mercury concentrations in blood. Also, blood cadmium concentrations were associated with maternal age and having a bus garage near the place of residence. Conclusion: This study suggests that smoking status, dietary patterns and the environmental status near the residence should be considered as important factors for preventable sources of heavy metal exposure in preschoolers.

• KIEAE Journal
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• 제16권6호
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• pp.135-142
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• 2016

Purpose: The purposes of this paper are to investigate effects of indoor thermal environment on acoustical perception and effects of acoustics on indoor thermal perception, and to understand basic human perception on indoor environment. Method: Subjective assessment was performed in an indoor environmental chamber with 24 university students. Thermal conditions with PMV -1.53, 0.03, 1.53, 1.83 were simulated with a VRF system, a humidifier, a dehumidifier, and a ventilation system. Six noise sources - Cafe, Fan, Traffic, Birds, Music, Water- with sound levels of 45, 50, 55, 60 dBA were played for 2 minutes in random order. Temperature sensation, temperature preference, humidity sensation, humidity preference, noisiness, loudness, annoyance, and acoustic preference were assessed using bipolar visual analogue scales. The ANOVA and Turkey's post hoc test were used for data analysis. Result: Thermal environmental perceptions were not altered through 2 minutes noise exposure. Acoustical perceptions were altered by thermal conditions. The results were consistent with previous papers, however, the noise exposure time should be carefully considered for further development.

• Journal of the korean society of oceanography
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• 제37권2호
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• pp.82-89
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• 2002

Butyltins (BTs) were measured in 2 species of shellfish and 16 species of fish collected along the Korean coast. Tributyltin (TBT) was detected in the mussels and oysters of sentinel organisms (20 to 940 ng Sn/g dry wt), indicating widespread contamination of TBT in the Korean coast. The elevated concentrations of TBT in the shellfish found in the sites near harbors or shipyards suggested that antifouling paints are probable major sources of butyltins in these areas. The TBT compound was detected in 12 out of 16 fish samples. The concentrations of TBT in fish muscles wee between 7 and 151 ng Sn/g dry wt, while the level in whole body of anchovy was very high (793 ng Sn/g dry wt). Exposure doses to Korean people via consumption of these marine products wee evaluated. The results suggested that the environmental levels of TBT were below the level of concern.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.727-734
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• 2008

This research presents a laboratory study about difference of subjective response between with and without pictures. A main source is impulsive sound caused by leisure shooting. The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of the jury test adopted a Semantic Difference(SD) Method. The intersection point which two lines crossed was used as reference point. The intersecting point of mean response rating between with and without pictures was approximately 44ASEL and that of %HA was about 60ASEL. In the result of the test, the negative effect of pictures was given at a lower levels than intersection point while the positive effect was given at a higher levels than that.

• 한국소음진동공학회논문집
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• 제18권7호
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• pp.746-755
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• 2008

This research presents a laboratory study on subjective response of impulsive sound caused by construction site (breaker and blasting). The sources are sampled from outdoor noise and their levels range from 40 to 75 dBA at the interval of 5 dBA. The noise unit is based on A-weighted sound exposure level(ASEL; $L_{AE}$). To make equal ASEL of listening level, finite impulse response(FIR) filter is applied to the originally sampled source to include the effect of propagation attenuation. Sixty-three subjects, forty-two males and twenty-one female, between 18 and 29 years of age, participated in the experiment. The evaluation method of jury test adopted a semantic difference method(SDM). In the test results for impulsive noise, the subjective response of blasting noise was higher than that of breaker noise. The result of %HA that has been combined responses of the three methods except for pink-noise was executed by regression analysis and was shown as the following equation.: $%HA=746.53/(1+{\exp} (L_{AE}-93.3))+0.34$.

• 한국물환경학회지
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• 제18권4호
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• pp.395-400
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• 2002

Lead is one of the most toxic metal and is detectable in practically all phases of environment and in all biological system. Transport, industrial and domestic waste products are the main sources of this pollutant. Ingested lead is rapidly absorbed and widely distributed throughout the body, causing extensive tissue damage. In this study, we chose the freshwater decapods Maceobrachium nipponnese as a sensitive indicator organism for environmental pollution. In order to investigate the possibility in use of $Na^+/K^+ATPase$ activity as a biomarker of lead pollution, we tested the acute toxicity of lead to Maceobrachium nipponnese. The $LC_{50}(96hr)$ value for lead in Maceobrachium nipponnese was found to be $446{\mu}g/L$ with the 95% confidence limits. The lead exposure group at $LC_{50}$ showed a significant $Na^+/K^+ATPase$ inhibition, depending on the exposure time. Comparision of several concentrations of lead revealed that the $Na^+/K^+ATPase$ activity in Maceobrachium nipponnese was significantly decreased in a concentration dependent manner. These results suggest that $Na^+/K^+ATPase$ activity in Maceobrachium nipponnese may possibly be used as a biomarker of lead pollution in aquatic ecosystem.

• 환경위생공학
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• 제15권4호
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• pp.134-141
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• 2000

The person' spending time in underground s[aces within indoor environment show a tendency to increase every year, but in Korea, levels and sources of pollutant in underground spaces have not been well-characterized. Therefore, as part or a larger indoor environmental study, conducted at subway station in Seoul, nitrogen dioxide was measured using passive samplers in 16 subway stations, 2 tunnels and 70 workers of subway station. The mean concentrations of nitrogen dioxide in subway stations were $27.87{\pm}7.15$ ppb at station office, $35.76{\pm}8.35$ ppb at platform, $52.60{\pm}13.04$ ppb at outdoor, respectively, and the Indoor/Outdoor ratio were 0.49~0.93. The mean concentrations of nitrogen dioxide in tunnels were $44.91{\pm}4.67$ ppb in Chunggye-Nowon tunnel with a single track, $42.55{\pm}3.33$ ppb in Mokkol-Taenung tunnel with double track, respectively, and as a result of t-test, a single track levels were higher than double track levels(p<0.05). The mean personal exposure of the subject of station workers was $29.40{\pm}9.75$ ppb.

• Ocean and Polar Research
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• 제39권2호
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• pp.107-114
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• 2017

In this study, we investigated the effects of light spectra on physiology stress and DNA damage in juvenile rock bream (Oplegnathus fasciatus) using light-emitting diodes (LEDs; green, 520 nm; red, 630 nm) at two intensities (0.25 and $0.5W/m^2$ ) with application of thermal stress (25 and $30^{\circ}C$). We measured the mRNA expression of heat shock protein 70 (HSP70) and the levels of plasma cortisol, glucose, aspartate aminotransferase (AspAT), and alanine aminotransferase (AlaAT). Additionally, DNA damage was measured using comet assays. Our findings showed that HSP70 mRNA expression and plasma cortisol, glucose, AspAT, and AlaAT levels were significantly higher after exposure to high temperatures and were significantly lower after exposure to green LED light. Thus, although high water temperatures induced stress in juvenile rock bream, green LED light inhibited stress. In particular, green LED light reduced stress and DNA damage to a greater degree than other light sources.