• Title/Summary/Keyword: Environmental Research

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Study on the methods of risk assessment of human exposure by using of PVC flooring (PVC 바닥재 인체 노출에 따른 위해성 평가 연구)

  • Kim, Woo Il;Cho, Yoon A;Kim, Min Sun;Lee, Ji Youmg;Kang, Young Yeul;Shin, Sun Kyoung;Jeong, Seong Kyoung;Yeon, Jin Mo
    • Analytical Science and Technology
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    • v.27 no.5
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    • pp.261-268
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    • 2014
  • In advanced countries, a variety of consumer exposure assessment models including CONSEXPO, are developed to manage risks of consumer products containing hazardous materials. The models are used to assess the risks of exposure to hazardous chemicals in consumer products, which serves as a foundation for regulation standards. In this study, exposure assessment models applicable for various scenarios were reviewed and a proper model was applied for the selected products and risk assessment was conducted at each stage to establish a risk assessment procedure for different types of products. Based on the exposure scenario, exposure factor was selected and according to the algorithm produced based on CONSEXPO exposure model, some level of phthalates were detected from some types of PVC flooring. However, a correlation between phthalate content and migration rate showed r-square 0.0065, little correlation, which is inadequate for estimating standard value. For this reason, it seems valid that the current standard be in place. Additionally, any new standard was not suggested as VOCs were not found harmful to human health, allowing the existing standard to be continuously applied. No migration rate was found for heavy metals and risk assessment was not performed accordingly. In this aspect, it is presumed that hazards to health through dermal exposure would be very little.

Evaluation of Fluoride Distribution, Fate and Transport Characteristics in Soils (토양 중 불소 분포 및 거동 특성 평가)

  • Lim, Ga-Hee;Lee, Hong-Gil;Kim, Hyoung-Seop;Noh, Hoe-Jung;Ko, Hyoung-Wook;Kim, Ji-In;Jo, Hun-Je;Kim, Hyun-Koo
    • Journal of Soil and Groundwater Environment
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    • v.23 no.6
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    • pp.90-103
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    • 2018
  • Although fluoride is an essential trace element, ingestion of excessive amount of fluoride could have detrimental effect on human health. Generally, the bioavailability of fluoride in soils was low, but it could be harmful to the environment depending on the soil properties. Therefore, it is necessary to understand the concentration distribution, and fate and transport characteristics of fluoride to establish a resonable management strategy for fluoride pollution. This study was conducted to evaluate nationwide fluoride distribution in soils in Korea, as well as its fate and transport characteristics. The average background concentration was 204.5 (15.3~504.8) mg/kg, which is lower than the values of foreign soils. For the three regions of different land use, the average concentration was 229.6 mg/kg in region 1, 195.7 mg/kg in region 2, and 273.4 mg/kg in region 3. The concentration of fluoride was the highest in soils from Youngnam block within tectonic structure derived from metamorphic rocks. The results of sequential extraction to access F bioavailability showed fluoride in soils mainly existed as a residual form, which suggests the bioavailability of fluoride was relatively low. Soil properties such as soil pH, CEC, and clay content were found to affect F bioavailability of soil.

Effect of Environmental Factors on Phytoplankton Communities and Dominant Species Succession in Lake Cheongpyeong (환경요인에 따른 청평호 식물플랑크톤 군집 및 우점종의 천이 특성)

  • Youn, Seok Jea;Kim, Hun Nyun;Im, Jong Kwon;Kim, Yong-Jin;Baek, Jun-Soo;Lee, Su-Woong;Lee, Eun Jeong;Yu, Soon Ju
    • Journal of Environmental Science International
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    • v.26 no.8
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    • pp.913-925
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    • 2017
  • Phytoplankton populations were examined at three sites in Lake Cheongpyeong, South Korea from March 2008 to December 2016, including measurement of phytoplankton communities and their dominant species, abundance and environmental factors. The annual average ranges of water temperature, dissolved oxygen and conductivity were $15.2-18.8^{\circ}C$, 10.3-12.2 mg/L, $86-140{\mu}S/cm$, respectively, with similar values at all studied sites. The highest phytoplankton cell density was observed in spring and fall, and it subsequently decreased rapidly during heavy rainfall. Diatoms were dominant in spring (mainly Stephanodiscus hantzschii, Asterionella formosa) and fall (mainly Aulacoseira granulata), while greenalgae and cyanobacteria had high appearance in early-summer and summer, respectively, indicating that water temperature is the most important factor influencing their growth. Stephanodiscus hantzschii and Asterionella formosa frequently occurred at low water temperature ($4.5-15.0^{\circ}C$ and $5.4-21.6^{\circ}C$, respectively) while Aulacoseira granulata and Anabaena spp. were favored by high water temperature (8.6-28.4 and $14.9-26.2^{\circ}C$, respectively) and phosphorus. Additionally, Fragilaria crotonensis occurred at low nutrient conditions. Rhodomonas spp. frequently appeared year-round.

Contamination Characteristics of Agricultural Groundwater Around Livestock Burial Areas in Korea (가축매몰지 주변 농업지역 지하수의 수질오염 특성 분석)

  • Kim, Hyun Koo;Park, Sun Hwa;Kim, Moon Su;Kim, Hye Jin;Lee, Min Kyeong;Lee, Gyeong-Mi;Kim, So-Hyun;Yang, Jae-Ha;Kim, Tae Seung
    • The Journal of Engineering Geology
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    • v.24 no.2
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    • pp.237-246
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    • 2014
  • Seasonal variations of major contaminants in groundwater around livestock burial areas in Gyeonggi province, Korea, were examined. Seven typical contamination indicators ($NO_3$-N, $NH_3$-N, chloride, pH, DO, ORP, and EC) were monitored in groundwater samples collected from 84 wells located within 60 m of livestock burial sites for the leachate plume emanating from the livestock burial sites. The monitoring results of pH, DO, ORP, and EC revealed minimal seasonal variations, providing no evidence for leachate plumes. The $NO_3$-N concentrations were below 30 mg/L and exhibited minimal seasonal fluctuations, even in the wells located close to (< 20 m) the burial sites; the $NH_3$-N and chloride concentrations also showed similar results. The contamination indicators examined in this study indicate that the observed groundwater contamination is primarily from preexisting pervasive contamination due to agricultural activities and livestock farming, not leachates derived from nearby livestock burial sites.

Identification and Phylogenetic Analysis of Culturable Bacteria in the Bioareosol from Several Environments (환경 유형에 따른 바이오에어로졸 중 배양성 세균 동정 및 계통분석)

  • Lee, Siwon;Chung, Hyen-Mi;Park, Su Jeong;Choe, Byeol;Kim, Ji Hye;Lee, Bo-Ram;Joo, Youn-Lee;Kwon, Oh Sang;Jheong, Weon Hwa
    • Microbiology and Biotechnology Letters
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    • v.43 no.2
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    • pp.142-149
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    • 2015
  • Bioaerosols are comprised of particles 0.02-100 μm in size that originate in natural and artificial environments, and as a result of human activities. They consist of microorganisms including viruses, bacteria, fungi, and protozoa; fungal spores; microbial toxins; pollen; plant or animal material; expectorated liquid from humans; and glucans (peptidoglycan and β-glucan). Bioaerosols can cause respiratory and other diseases in humans and animals. In this study, bioaerosol samples acquired from agricultural sources, livestock, a sewage treatment plant, a beach, and a pristine area were analyzed to identify and phylogenetically characterize culturable microorganisms. The isolated bacteria exhibited regional differences, with different species dominating. However, Bacillus cereus was isolated in all samples, with a total of 31 strains isolated from all areas, and Acinetobacter baumannii was isolated from an indoor poultry farm. In addition, bacteria determined to be of novel genus or species of the genera Domibacillus, Chryceobacterium, Nocardioides and family Comamonadaceae were isolated from the agricultural, livestock and beach environments.

Total content characteristics of inorganic and organic substances from wastes from thermal processes (열처리 공정에서 발생하는 무기·유기물질류의 함량특성)

  • Yeon, Jin-Mo;Kim, Woo-Il;Kang, Young-Yeul;Jeon, Tae-Wan;Jeong, Seong-Kyeong;Cho, Yoon-A;Kim, Min-Sun;Shin, Sun-Kyoung;Oh, Gil-Jong
    • Analytical Science and Technology
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    • v.27 no.5
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    • pp.254-260
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    • 2014
  • In this study, heavy metals, PCDD/PCDFs, PAHs in wastes generated from thermal processes were analyzed. Waste from lead thermal metalurgy (EWC 10 04) inorganic metal substances in the regulation were detected in the highest concentrations of Pb. EWC 10 04 seems to be a result of the dust. Waste from zinc thermal metalurgy (EWC 10 05) inorganic metal substances in the regulation were detected in high concentration of Zn. EWC 10 05 seems to be a result of the dust. Waste from copper thermal metalurgy (EWC 10 06) Cu in the 651,77 mg/kg to 651 times higher than regulation standard appeared in the copper thermal metallurgy process seems to be a result of dust. The concentrations of PCDD/PCDFs ranged from 0.0005~11.748 ng-TEQ/g in dust, 0.0027 ng-TEQ/g in fly ash. PCDD/PCDFs content was not detected in excessive value in regulation standard. PAHs concentration was in the range of ND~118.9 mg/kg in Naphthalene, ND~9.6 mg/kg in Phenanthrene, ND~48.4 mg/kg in Benzo[b]fluoranthene, ND~62.6 mg/kg in Benzo[a]pyrene, ND~10.7 mg/kg in Fluoranthene, ND~11.5 mg/kg in Benzo[a]anthracene.

Analysis of mercury and methylmercury in river sediment samples (하천퇴적물 중의 수은 및 메틸수은 분석 연구)

  • Lee, Jung-Sub;Park, Jae-Sung;Kang, Hak-Gu;Cho, Jae-Seok;Hong, Eun-Jin;Jeong, Gi-Taeg;Cha, Jun-Seok;Jung, Kwang-Yong;Kim, Young-Hee
    • Analytical Science and Technology
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    • v.22 no.1
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    • pp.44-50
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    • 2009
  • In this study, the use of purge & trap GC-MS technique for determination of methylmercury in sediment samples was described. The method detection limit of the method was determined as 0.06 ng/g and the recovery of the method was $102{\pm}11.4%$, with precisions better than 11.2%. The method was validated by analysis of CRMs such as ERM CC580 (estuarine sediment) and IAEA 405 (sediment). Additionally, the performance of the method was tested on river sediment samples and the analytical results were compared with those of the GC-CVAFS, which has been widely used for methylmercury analysis.