• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.175-183
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• 2001

Immersion tests with artificial seawater were carried out to investigate the resistance to seawater attack of 5 types of cement matrices. From the results of compressive strength and length change, it was found that blended cement mortars due to mineral admixtures, were superior to portland cement mortars with respect to the resistance to seawater attack. Moreover, XRD analysis indicated that the peak intensity ratio of low heat portland cement(LHC) paste, in portland cement pastes, had better results, and so did that of blended cement Paste. Pore volume of pastes by mercury intrusion porosimetry method demonstrated that total pore volume of ordinary portland cement(OPC) paste had a remarkable increase comparing with that of other pastes. In case of immersion of artificial seawater, the use of ground granulated blast-furnace slag and fly ash, however, showed the beneficial effects of 56% and 32% in reduction of total pore volume, respectively.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.377-389
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• 2020

In this study, pollution characteristics were investigated for the Andong Dam sediments in the Nakdong River. Sediment samples were collected from the middle, left, and right points of the lake up to 40km upstream of the Andong Dam at intervals of about 5km by stratification and turnover period. In the case of nutrients and total organics such as loss of ignition, total nitrogen, and phosphorus, the degree of contamination is low, but heavy metals of arsenic and cadmium is very high. The contamination level of sediments in the dam area is higher than that of the branch of river and the control group, and concentration of chromium, copper, and lead are higher in the stratification period, and that of zinc is higher in turnover period. Arsenic, cadmium, manganese, and zinc showed contamination variation between upstream and downstream but chromium, copper, mercury, iron and lead didn't show the variation.

• Animal Bioscience
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• v.35 no.9
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• pp.1408-1417
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• 2022

Objective: The objective of this study was to determine whether dietary black soldier fly (Hermetia illucens, HI) larvae oil (HILO) could serve as an alternative fat source to soybean oil (SBO) in laying hen diets. Methods: We randomly assigned 25-week-old Hy-line Brown laying hens (n = 144) to receive (n = 6 hens/group; eight replicates) a control or an experimental diet in which SBO was replaced with 50% (50HILO) or 100% HILO (100HILO). Results: Dietary HILO did not negatively affect body weight or productive performance during the study. The eggs also had similar quality parameters, proximate composition, and cholesterol levels. However, the yolk color index was significantly higher (p<0.01) in the 100HILO than in the other groups. Dietary HILO significantly altered the composition of fatty acids (FAs) in abdominal fat and eggs. Total saturated fatty acids (SFAs) and total polyunsaturated FAs (PUFAs) were significantly increased and decreased in the 50HILO and 100HILO groups, respectively, compared with those in the control group (p<0.001 and p<0.0001, respectively). Specifically, the medium-chain FAs lauric and myristic acids were remarkably increased in the abdominal fat of laying hens fed HILO (p<0.0001), whereas only myristic acid increased in eggs (p<0.0001). Undesirable heavy metal (aluminum, fluorine, arsenic, lead, mercury, and cadmium) concentrations were below permissible limits in eggs. Conclusion: We considered that HILO could be an alternative dietary fat to SBO for laying hens with maintained productive performance and good egg quality.

• Journal of Nutrition and Health
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• v.45 no.4
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• pp.347-361
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• 2012

Limited studies are available concerning the effect of heavy metal exposure on cardiovascular diseases. As environmental pollution increases, food contamination, including heavy metal contamination of fish, also increases. However, researches based on the intake of heavy metals, cardiovascular disease, and fish intakes are inconclusive. We assessed an association of heavy metal exposure with cardiovascular disease and fish intake in a nationally representative group of general Korean adults. We used data from the combined 2008-2010 Korean National Health and Nutrition Examination Survey (KNHANES), and analyzed the data of 5,139 Koreans who participated in KNHANES. All participants were older than 20 years, and were diagnosed with stroke, ischemic heart disease, or hypertension. The mean blood cadmium, lead concentration, and mercury concentration of subjects were $1.07{\pm}0.01{\mu}g/L$, $2.49{\pm}0.02{\mu}g/dL$, and $5.19{\pm}0.08{\mu}g/L$, respectively. We used the survey logistic regression model to account for the complex sample design of the cardiovascular disease risk in order to estimate the odds ratios (OR). After adjusting for age, education, income, alcohol, smoking, and BMI, the increase of serum cadmium in blood was associated with the increase in the prevalence of hypertension. Further, the increase in blood cadmium concentration was associated with the increase of both systolic blood pressure (SBP) and diastolic blood pressure (DBP). Although higher fish intakes were significantly associated with higher blood mercury concentration (p for trend < 0.0001), fish intakes did not affect either blood cadmium or lead concentration. Comparing the highest fish intake group with the lowest intake group, the OR of hypertension was 0.31 (95% CI: 0.19-0.59) in the crude model for total fish. However, these associations were no longer significant after the adjustment for potential confounding factors. In conclusion, cadmium in blood was associated with an increased risk of hypertension in the general Korean adult population. However, we found no evidence of a clear relationship between cardiovascular disease and frequency of fish consumption.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.305-318
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• 1999

This study were conducted to estimate the values of the heavy metal in the fresh water fish and shellfish collected from fish market. The levels of the heavy metal were determined in a total of 319 samples of 11 species of the fresh water fish and 14 species of the shellfish by mercury analyzer and atomic absorption spectrophotometer. The results of this study were summerized as follows; The average contents of the heavy metal in the fresh water fish were Pb 0.075, Hg 0.05:3, Cd 0.002, Cr 0.135, Fe 8.695, Mn 1.078, Zn 9A91, Cu 0.548 mg/ kg. The average contents of the heavy metal in the shellfish were Pb 0.059. Hg 0.007, Cd 0.146, Cr 0.147, Fe 40.808, Mn 7.738, Zn 13.943, Cu 2.7:31 mg/kg. Being compared the average contents of the heavy metal of the fresh water fish with those of shellfish, the average contents of Cd, Fe, Mn, Cu in the shellfish were significantly higher than in the fresh water fish(P<0.001). Depending on the sampling areas, the average contents of the heavy metal were different by districts. The contents of the heavy metal were changed with the seasons(P<0.05).

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.460-465
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• 2007

Endosulfan-${\alpha}$ endosulfan-${\beta}$ and endosulfan-sulfate, which are classified as pesticides, were degraded by use of UV energy and ultrasonic irradiation. The degradation residuals were analysed by gas chromatography with an electron capture detector and TOC (total oragnic carbon) analysis. The reactions were conducted in a quartz annular reactor equipped with a low pressure mercury multilamp (8Wx2) and a sonic generator. All the aqueous solutions were concentrated as 10 mg/L initially. Endosulfans were degraded each to result in 48.2% (${\alpha}$), 50.0% (${\beta}$) and 76.5% (sulfate) of removal efficiency by UV energy, and 66.9% (${\alpha}$), 55.8% (${\beta}$) and 72.7% (sulfate) by ultrasonic irradiation, respectively. In contrast to the results of the single-component solutions, degradation of the endosulfan-sulfate was greatly suppressed to result in the lowest degradation rate and removal efficiency in the three-component solutions. This finding suggests that there should be a reversible reaction with a substantially low equilibrium constant between endosulfan-${\alpha}$ or -${\beta}$ and -sulfate in the coexistence of the three endosulfans. TOC data showed the endosulfans were decomposed by 20%~40% toward complete mineralization, producing a quantity of intermediates induced by the radical reactions. We found that all the decay reactions considered in this study nicely fell into pseudo first-order rate.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.10
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• pp.590-595
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• 2015

Sampling campaigns were conducted for hazardous chemicals and heavy metals in influents and effluents of industrial wastewater treatment plants (WWTPs) in Korea for best management practices (BMPs) of those pollutants through the plants and the receiving water bodies. Twenty seven WWTPs, receiving wastewater from industrial complexes and treating more than $2,000m^3/day$, were selected for the sampling campaign. Influents and effluents of each WWTPs were sampled once a month (total three times per plant) between July and September, 2012, and analyzed for 22 hazardous water pollutants among 28 regulated for effluents limits in Korea. Concentrations of mercury, arsenic, 1,1-dichloroethylene, and benzene in the influents were relatively higher; concentrations of mercury and arsenic in effluents were relatively higher than those of other pollutants. Most of the hazardous chemicals and heavy metals were removed (including phase transfer) more than 60% through the treatment processes except for selenium (30% removal) and 1,4-dioxane (18% removal).

• Korean Journal of Medicinal Crop Science
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• v.24 no.2
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• pp.121-128
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• 2016

Background: Turmeric (Curcuma longa L.) that is used as a food material has antioxidant, anticancer and anti-inflammatory properties. Recently the demand for functional foods and drugs has increased. The present study was carried out to determined of contents of residual sulfur dioxide, heavy metals, ash, acid insoluble ash and curcuminoids in turmeric from the Seoul Yak-ryeong market. Methods and Results: A total of 31 samples were obtained. Residual sulfur dioxide was not detected in any samples. Heavy metals (arsenic, cadmium, lead and mercury) were analyzed by ICP-MS (Inductively Coupled Plasma Mass Spectrometer) and a mercury analyzer and were detected in the ranges of 0.00 - 0.28, 0.00 - 0.07, 0.00 - 0.29 and 0.002 - 0.027mg/g respectively. No significant difference were observed between the average heavy metal contents of domestic and imported tumeric. However, average content of ash in domestic samples (7.8%) were significantly higher than that in imported samples (6.1%), whereas that of curcuminoids was significantly higher in imported samples (47.6mg/g) than in domestic samples (11.2mg/g). The average content of acid insoluble ash was not significantly different between two sample types (0.9% in each). Conclusions: There are no specific standards for turmeric used as food materials. Therefore, this study can be provided as basic data for the establishment of quality standards for turmeric.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.3
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• pp.213-223
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• 2023

A total of 81 handmade soaps on sale on the market were collected from January to November 2022. To compare quality characteristics, all ingredients were referred to, and the pH, dry reduction, heavy metals (lead, arsenic, cadmium, antimony, and mercury), and contents of free alkali were measured. All soaps had a slightly alkaline pH of 7.9 to 11.2, average drying loss was 17.6%, and free alkali was hardly detected. The average values of all heavy metals were 0.104 ㎍/g for lead, 0.035 ㎍/g for arsenic, 0.002 ㎍/g for cadmium, 0.048 ㎍/g for antimony, and 0.0003 ㎍/g for mercury. The results of handmade soap were below the recommended in regulations on safety standards for cosmetics of Ministry of Food and Drug Safety.

• Journal of the Korean earth science society
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• v.21 no.5
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• pp.611-622
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• 2000

To investigate the exchange rates of mercury(Hg) across soil-air boundary, we undertook the measurements of Hg flux using gradient technique from a major waste reclamation site, Nan-Ji-Do. Based on these measurement data, we attempted to provide insights into various aspects of Hg exchange in a strongly polluted soil environment. According to our analysis, the study site turned out to be not only a major emission source area but also a major sink area. When these data were compared on hourly basis over a full day scale, large fluxes of emission and deposition centered on daytime periods relative to nighttime periods. However, when comparison of frequency with which emission or deposition occurs was made, there emerged a very contrasting pattern. While emission was dominant during nighttime periods, deposition was most favored during daytime periods. When similar comparison was made as a function of wind direction, it was noticed that there may be a major Hg source at easterly direction to bring out significant deposition of Hg in the study area. To account for the environmental conditions controlling the vertical direction of Hg exchange, we compared environmental conditions for both the whole data group and those observed from the wind direction of strong deposition events. Results of this analysis indicated that the concentrations of pollutant species varied sensitively enough to reflect the environmental conditions for each direction of exchange. When correlation analysis was applied to our data, results indicated that windspeed and ozone concentrations best reflected changes in the magnitudes of emission/deposition fluxes. The results of factor analysis also indicated the possibility that Hg emission of study area is temperature-driven process, while that of deposition is affected by a mixed effects of various factors including temperature, ozone, and non-methane HCs. If the computed emission rate is extrapolated to the whole study area we estimate that annual emission of Hg from the study area can amount to approximately 6kg.