• Journal of Soil and Groundwater Environment
• /
• v.19 no.1
• /
• pp.46-53
• /
• 2014

The purpose of this study is to promote utilization of paper mill sludge as an adsorbent for stabilizing heavy metals in contaminated water by measuring the adsorption capacity of paper mill sludge for cadmium and arsenic. To measure adsorption capacity of paper mill sludge, sorption isotherm experiments were analyzed by Langmuir and Freundlich isotherm models. Also, two methods of chemical modifications were applied to improve the adsorption capacities of paper-mill-sludge: the first method used sodium hydroxide (NaOH), called PMS-1, and the second method used the NaOH and tartaric acid ($C_4H_6O_6$) together, called PMS-2. For Cd adsorption, PMS-1 presented the increase of reactivity while PMS-2 presented the decline of reactivity compared to that of untreated paper-mill-sludge. In case of As adsorption, both PMS-1 and PMS-2 showed the decrease of adsorption capacities. This is because zeta-potential of paper mill sludge was changed to more negative values during chemical modification process due to the hydroxyl group in NaOH and the carboxyl group in $C_4H_6O_6$, respectively. Therefore, we may conclude that the chemical treatment process increases adsorption capacity of paper mill sludge for cation heavy metals such as Cd but not for As.

• Journal of the Korean Chemical Society
• /
• v.28 no.6
• /
• pp.403-411
• /
• 1984

Amberlite XAD-7 and XAD-4 resins impregnated with DXHQ (5,7-dihalo-8-hydroxyquinoline) were prepared for the adsorption, separation and recovery of heavy metal ions from aqueous solutions. The characteristics of the impregnated resins, DXHQ (X : Cl, Br, I)-XAD were studied to find out the proper pairs of resin and DXHQ for the adsorption of metal ions. The increasing order of the impregnated amount of DXHQ onto XAD-7 resin was as follows: DCHQ < DBHQ < DIHQ. It was observed from the plot of log $K_d$ vs. pH that the optimum pH range for the adsorption of DIHQ onto XAD-4 resin was from 3.0 to 7.0. The stabilities of the DXHQ-XAD resins were investigated by measuring the amount of DXHQ remained on the XAD resin after shaking the DXHQ-XAD resins in various solutions of pH ranging from 2 to 12 and hydrochloric acid solutions. The impregnated resins were considerably stable in both acidic and neutral solutions. The amount of DIHQ leached from DIHQ-XAD-4 resin by eluting with various HCl solutions (1 ∼ 5M) was negligible, but in the case of XAD-7 resin it increases as the concentration of HCl solution increases. The optimum pH ranges, absorption mole ratio (M : DXHQ) and adsorption capacities (mmol metal per gram of resin) for the adsorption of metal ions onto the DXHQ-XAD resins were determined respectively. The stability of metal ion absorbed by the DXHQ-XAD resins was observed as the following order: M-DCHQ-XAD-7 < M-DBHQ-XAD-7 < M-DIHQ-XAD-7. The adsorbed metal ions were quantitatively recovered by eluting with HCl (0.5 ∼ 5M) and DXHQ-XAD resins could be reused over 5 times without re-impregnation of DXHQ.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.50 no.3
• /
• pp.243-249
• /
• 2017

Crabs are a popular seafood item. However, they can harbor many microorganisms, heavy metals, radioactivity, and benzo(a)pyrene, which are potential health risks to humans. The objective of this study was to assess the potential of swimming crabs for use in foods such as Ganjang-gejang, by measuring their sanitary biological and chemical properties. Viable microbial cell counts in swimming crab samples were $3.4{\times}10^2-6.7{\times}10^4CFU/g$, but no coliform, Escherichia coli, or pathogenic bacteria, such as Vibrio parahaemolyticus, Enterohemorrhagic E. coli, Listeria monocytogenes, Staphylococcus aureus, or Salmonella spp., were detected. Heavy metal concentrations in swimming crab samples were non-detectable to 0.112 mg/kg for total mercury, non-detectable to 0.435 mg/kg for lead, and 0.115-0.836 mg/kg for cadmium. Benzo(a)pyrene concentrations ranged from $0.025-0.060{\mu}g/kg$, and the volatile basic nitrogen content ranged from 8.7-15.6 mg/100 g. No radioactivity was detected in samples. These results suggest that swimming crabs are viable for use in seafood products.

• Korean Journal of Health Education and Promotion
• /
• v.29 no.3
• /
• pp.53-61
• /
• 2012

Objectives: Improving public capability to obtain, understand, and use health information is important for decision-making and communication. This study attempts to measure adults' literacy of the information provided by a public health institution. Factors affecting different health literacy level are also investigated. The relation between public risk perception and health literacy is examined as well. Methods: A total of 800 korean adults were surveyed. To provide the participants health literacy questions, health messages of heavy metals released by KFDA as well as literacy questions developed by NIKL were used. A total of eight questions were developed to measure health literacy. The dimensions of risk perception proposed by Brewer et al.(2008) were modified to measure risk perception. Results: The average percentage of correct answer for all literacy questions was only 65.57%. Individuals at the older age, and with lower education/ income level were more likely to be low literate. In addition, health literacy was strongly associated with risk perception. Conclusions: Public literacy of health information is influenced by socio demographic factors. This study suggested a possibility that low health literacy may affect unrealistically high risk perception. Further studies with sophisticated methodologies to measure health literacy need to be developed.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.2
• /
• pp.299-306
• /
• 2001

As a part of basic investigation for utilization of canned food processing by-products, a food components of the canned oyster processing waste water such as boiled and released water(BRW), wash water(WW) were investigated and compared with hot-water extracts from oyster. From the results of measuring heavy metal conte수, viable cells and coliform group, the canned oyster processing waste waters might not invoke health risk in using food resource. The contents of taste compounds (free amino acids, ATP related compounds, TMA (O) and total creatinine) of BRW and WW accounted for about 254% and 95%, respectively, in comparison with those of control (hot-water extract from oyster). The BRW showed a very high content of salt in comparing to the WW and control. In descending order, the values of whiteness index was WW, control and BRW. Sensory scores for color, oyster flavor intensity and saline taste were not significantly different between WW and control. But, BRW had the highest score in oyster flavor intensity, while had the lowest score in color and saline taste. But, the color and saline taste of BRW might be able to control by some pretreatment (concentration and drying in mild condition, desalination and recipe control etc). These results indicated that BRW and WW generated from various step during canned oyster processing could be a potential food resource by controlling of saline taste and color intensity.

• Journal of agriculture & life science
• /
• v.53 no.1
• /
• pp.117-126
• /
• 2019

This paper presents an experiment to examine the possibility of treating carcass while making compost with a horizontal cylinder composting equipment. The findings were as follows: as for heavy metal content, zinc content was above the allowed level in some measuring sections of the general operation and the entire measuring sections of the carcass operation, whose copper content was higher than the general operation. The wood chip operation was lower than the allowed level in all the heavy metals and similar or the same as the carcass operation in copper, cadmium and arsenic. Its nickel content was 29.5~63.8%, which was relatively higher than 9.3~18.0% and 15.8~18.0% of the general and carcass operation, respectively. Its chrome content was 14.2~31.9%, which was relatively higher than that of the general and carcass operation. The integrated operation was lower than the allowed level in all the heavy metals. Its copper and zinc content was 34.9~54.5% and 53.1~75.9%, which was similar to 48.9~52.6% and 64.6~85.9%, respectively, in the wood chip operation. Its chrome and nickel content was stabilized while their content was rather high in the wood chip operation. The average and final moisture content of the carcass operation was 60.7% and 49.6%, respectively. Its average moisture content was a little bit higher than the recommended level of 55.0%, but its final moisture content was lower than the recommended level. The average and final moisture content of the integrated operation was 29.2% and 18.6%, respectively, which was the lowest level among the four operation modes. The overall moisture content of the operation modes was under the recommended level of 55.0% with some variance among the modes. The C/N ratio was the lowest in the carcass operation and the highest in the general operation. The average C/N ratio of the operation modes was in the range of 13.7~20.3 with the total average of 18.3, and the modes kept it under the proper level of 30.0.

• Korean Journal of Human Ecology
• /
• v.23 no.5
• /
• pp.861-871
• /
• 2014

This study explored applicability of natural dyeing and functional property of base paper using paper yarn and fabrics with green laver extracts. As a result of measuring dyeability and functional property of cotton, silk, and a blended fabric of cotton/mulberry, $60^{\circ}C$ and 40 minutes was the optimal dyeing condition for the cotton fabric under an alkali condition; $50^{\circ}C$ and 60 minutes for the silk fabric; $60^{\circ}C$ and 50 minutes for the blended fabric of cotton/mulberry. As a result of measuring the color fastness after dyeing cotton, silk and the blended fabric of cotton/mulberry, fastness to washing, water, rubbing, dry cleaning and light was superior. In terms of functional property, the silk and the blended fabric of cotton/mulberry were superior concerning antimicrobial properties of the fabric dyed with green laver extracts while the cotton fabric showed 90% or over. Regarding deodorization, the blended fabric of cotton/mulberry was the most superior. All the fabrics were harmless to the human body as they had heavy metal content below the standard. Considering the research results comprehensively, the green laver extracts possibly has enough applicability and functional property as a natural dyes. Moreover, it has potential to be developed new eco-friendly fashion materials.

• Journal of the Korean Chemical Society
• /
• v.20 no.4
• /
• pp.280-289
• /
• 1976

The silver selenide electrode has been prepared and its properties as an indicating electrode for silver ion have been investigated. Epoxy resin was used as a filler of silver selenide electrode. Silver metal plate was directly connected with the membrane of the electrode and the silver paste was used as its binder. The sintered electrode was more sensitive and stable than the pressed electrode, and the silver selenide electrode more sensitive than the silver sulfide electrode to silver ion. The linear relationship between the electrode potential and logarithmic concentration of silver ion has been observed down to 10-6 M for the electrode. Several heavy metal ions except mercuric ion did not interfere this linearity, but halide, cyanide, and thiocyanate ions did intensively interfere owing to the formation of silver compounds and complexes. This electrode has been applied to the potentiometric titration for determining halide ion. It is concluded that interferences from ,$CN^-, SCN^-, S^-, I^-, Br^-, Cl^- and Hg^{2+}$ ions are detrimental to the practical use of the electrodes for measuring pAg.

• Journal of Environmental Health Sciences
• /
• v.23 no.3
• /
• pp.27-39
• /
• 1997

This study, collaborated Gifu University, Japan, was performed to analyze chemical pollutants and microorganism and to clarify the distribution of sulfate-reducing bacteria and their insolubilization of heavy metal ions in leachates sampled seasonally between 1994 and 1996 from Nanjido waste landfill site, sampled 4 times between 1995 and 1996 from Pusan and Daejeon waste landfill site, and sampled 1 time between 1992 and 1994 from Hokkaido, Nagoya, Osaka and Hukuoka waste landfill site in Japan. The results were as follows: 1. The temperatures of internal leachate and leachate effluent were 40$\circ$C and 30$\circ$C, respectively, and the pH values of both leachates were about 8.0 at Nanjido waste landfill site. The concentration of SO$_4^{-2}$ gradually increased with the degree of stabilization and that of NO$_3$-N was detected in a part of sampling sites at one and half years, and in all sampling sites at 3 years after completion of landfill. 2. The organic substances in leachate of Nanjido waste landfill site decreased with the degree of stabilization and they were very fluctuated with measuring point and time. The concentration of organic substance and heavy metals in internal leachate were higher than in leachate effluent and those of Cd, Hg, and Pb were lower than detection limit except a part of samples in 1996. 3. APCs in internal leachate and leachate effluent were not much different and the minimum of APCs in internal leachate and leachate effluent were $1.0\times 10^4$/ml and $4.0\times 10^1$/ml, respectively. 4. The maximums of SRBs in Nanjido, Pusan, and Daejeon waste landfill site were 9180 MPN/ml, 24000 MPN/ml, and 348 MPN/ml, respectively and the maximum of SRBs in Japan waste landfill site was 9300 MPN/ml. 5. During 2-week-SRB culture, the values of MPN were high at 50$\circ$C for initial culture period and at 30$\circ$C for last culture period. MPN started to appear at first day and rapidly increased between 7th day and 9th day. 6. Cadmium and copper were insolubilized by SRB within 6 hr and iron and zinc were done within 48 hr. The rates of insolubilization of Cd, Cu, Fe, Zn, T-Cr were 100%, 99.5%, 95.0%, 99.8%, 16.1% after 48 hr treatment with SRB, respectively.

• Journal of Environmental Science International
• /
• v.17 no.9
• /
• pp.1005-1013
• /
• 2008

In this study, in order to analyze the air quality of the indoor environments of schools, we measured the indoor, outdoor and personal exposure concentration level of $PM_{10}$ for 40 classrooms(20 old, 20 new) in chungnam area from June 22 to July 19 and from November 21 to December 30, 2003. 1. Old classrooms contained more dust than new classrooms; the average of respirable dust is $43.27\;{\mu}g/m^3$ for new classrooms while $53.38\;{\mu}g/m^3$ for old one. The exposure concentration level of respirable dust in new classrooms were in summer higher outdoors than indoors. The values were indoors $46.71\;{\mu}g/m^3$, outdoors $50.46\;{\mu}g/m^3$, and personal $41.62\;{\mu}g/m^3$. Meanwhile in winter indoors had a higher concentration level than outdoors, the values being indoors $39.11\;{\mu}g/m^3$, outdoors $34.86\;{\mu}g/m^3$, and personal $49.01\;{\mu}g/m^3$. 2. Cr concentration level within dust was slightly higher in summer indoors ($101.50{\pm}32.10\;ng/m^3$) and outdoors ($100.89{\pm}35.18\;ng/m^3$) than winter indoors ($85.80{\pm}48.95\;ng/m^3$) and outdoors ($74.43{\pm}38.93\;ng/m^3$), but in personal concentration level, winter was higher. The results of this research show insufficient understanding of health risks from indoor air pollution, and shows possible health problems to students from school indoor air pollution. As such, a logical and systematic education program for students about the importance of indoor air quality should be carried out. Also the results of $PM_{10}$ concentration level measurements emphasize the need for regular measurements of indoor / outdoor and personal concentration level. New classrooms in particular needs to be used after measuring pollutants and safety, and requires installation of a ventilation device in all classrooms to improve air quality.