• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.435-447
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• 2011

This study was investigated to determine the contents of sulfur dioxide residues in medicinal herbs in Seoul Yang Nyoung Shi in 2010 (1,522 samples of 189 kinds). Samples were measured by modified Monier-Williams method. of the total samples, 618 samples (84 kinds) were domestic, and 904 samples (158 kinds) were imported. The content of sulfur dioxide in the domestics showed the range of 0.0 to 1,298.0 mg/kg (average 12.7 mg/kg), while those in imported samples were the range of 0.0 to 3,982.2 mg/kg (average 42.4 mg/kg). The average (mg/kg) amount of sulfur dioxide by parts in medicinal herbs was as follows; Tuber 122.3, Radix 69.3, Rhizoma 37.4, Cortex 33.3, Fructus 8.8, Ramulus 4.9, Semen 4.6, Folium 3.4, Flos 2.7, Perithecium 1.4. of the total samples (1,522), 52 samples (3.4%) were violated the KFDA regulatory guidance of sulfur dioxide. Among these 52 unsuitable samples, 16 samples (7 kinds) were domestic, and 36 samples (23 kinds) were imported. Approximately 88.1% of the total samples was less than 10 mg/kg of sulfur dioxide and 6.3% of the total samples showed more than 30 mg/kg of sulfur dioxide.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.202-208
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• 2012

A high-performance liquid chromatographic (HPLC) method was developed to determine residues of cyromazine, a triazine insecticide, in agricultural commodities. Cyromazine was extracted with 90% aqueous methanol from representative crops which comprised brown rice, oyster mushroom, oriental melon, watermelon, and Chinese cabbage. Following to evaporation of methanol in the extract, the aqueous concentrate was acidified to form the protonated cyromazine. Dichloromethane partition was then applied to remove nonpolar co-extractives in the aqueous phase. Strong cation-exchange chromatography using Dowex 50W-X4 resin was employed for final purification of the extract. Cyromazine was successfully separated on a Zorbax SB-Aq $C_{18}$ column showing high retention for polar compounds. Cyromazine was sensitively quantitated by ultraviolet absorption at 214 nm. Limit of quantitation (LOQ) of the method was 0.04 mg/kg irrespective of sample types. Each crops were fortified at 3 different concentrations of cyromazine for recovery test. Mean recoveries from samples fortified at LOQ~2.0 mg/kg in triplicate ranged 80.2~103.3% in five agricultural commodities. Relative standard deviations in recoveries were all less than 6%. A selected-ion monitoring LC/MS method with electrospray ionization in positive-ion mode was also provided to confirm the suspected residue. The proposed method was reproducible and sensitive enough to routinely determine and inspect the residue of cyromazine in agricultural commodities.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.238-244
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• 2009

This survey was conducted as a surveillance program following the establishment of safety guidelines for agricultural products in Korea. Concentrations of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) were measured in 421 samples using a mercury analyzer or ICP-MS. The average levels of Pb in mg/kg were 0.021 for rice, 0.020 for corn, 0.028 for soybeans, 0.034 for red beans, 0.025 for sweet potatoes, 0.021 for potatoes, 0.019 for Chinese cabbage, 0.031 for spinach, 0.021 for Welsh onions, and 0.011 for radishes. The average levels of Cd in mg/kg were 0.021 for rice, 0.002 for corn, 0.020 for soybeans, 0.006 for red beans, 0.008 for sweet potatoes, 0.011 for potatoes, 0.007 for Chinese cabbage, 0.035 for spinach, 0.006 for Welsh onions, and, 0.006 for radishes. The average levels of As in mg/kg were 0.103 for rice, 0.005 for corn, 0.007 for soybeans, 0.005 for red beans, 0.005 for sweet potatoes, 0.004 for potatoes, 0.007 for Chinese cabbage, 0.015 for spinach, 0.009 for Welsh onions and, 0.006 for radishes. Finally, the average levels of Hg in ${\mu}g/kg$ were 2.3 for rice, 0.2 for corn, 0.6 for soybeans, 1.4 for red beans, 0.1 for sweet potatoes, 0.3 for potatoes, 0.5 Chinese cabbage, 2.1 for spinach, 0.5 for Welsh onions, and 0.2 for radishes. Based on the Korean public nutrition report 2005, these levels (or amounts) are calculated only at 2.6% for Pb, 8.7% for Cd, 1.2% for Hg of those presented in provisional tolerable weekly intake (PTWI) which has been established by FAO/WHO. Therefore, the levels presented here are presumed to be adequately safe.

• Journal of Food Hygiene and Safety
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• v.24 no.1
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• pp.56-62
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• 2009

Patulin, a mycotoxin mainly produced by Penicillium and Aspergillus, is found in various foods. In the present, a maximum acceptable level for patulin is established at $50{\mu}g/kg(ppb)$ in apple juices and apple concentrates in Korea. But patulin may be detected in foods produced with other fruits. In the present study, patulin contamination was analyzed in 520 samples of fruit juices and beverages, and 50 samples of fruit juice concentrates. High performance liquid chromatography(HPLC) was applied to quantitatively analyze patulin levels in samples and liquid chromatography-mass spectrometry(LC/MS/MS) was used to remove false positive results. The results showed that three samples of 520 fruit juices and beverages and five samples of 50 fruit juice concentrates were contaminated by patulin, $9.8-18.0{\mu}g/kg$ and $4.7-18.2{\mu}g/kg$ respectively. Contaminated samples were produced with apple, orange or pear. This indicates that it is necessary to extend the regulatory range of patulin. In the other hands, the present study confirmed the effectiveness of LC/MS/MS analytical method to remove false positive results.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.272-277
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• 2016

The purpose of this study was to investigate present status of use about antimicrobial agent (triclosan, ethanol) and preservatives (sodium benzoate, methyl p-hydroxybenzoate, propyl p-hydroxybenzoate) in dentifrice. 75 samples including 16 mouthwashes were analyzed in this study. Contents of triclosan and preservatives were analyzed using by HPLC and ethanol was analyzed by headspace-GC. Preservatives were detected from total 37 samples, which are suitable for the legal limits in Korea. Methyl p-hydroxybenzoate was detected from 26 samples (0.003~0.19%), propyl p-hydroxybenzoate was detected from 11 samples (0.002~0.02%) and sodium benzoate was detected from 14 samples (0.1~0.3%), respectively. Methyl p-hydroxybenzoate was detected from 6 samples (0.03~0.19%), propyl p-hydroxybenzoate was detected from 1 samples (0.01%) and sodium benzoate was detected form 5 samples (0.1~0.2%) in 20 dentifrice for children. Triclosan was not detected from 75 samples. Ethanol was detected from 16 samples (4.9~21.9%) in 19 samples; among them three samples showed the higher contents (20.5~21.9%) but ethanol contents was not labeled in these samples.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.168-175
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• 2018

The use of microwave-assisted extraction and an acid-base clean-up process to determine the amount of methylmercury (MeHg) in marine products was suggested in order to improve the complicated sample preparation process. The optimal conditions for microwave-assisted extraction was developed by using a 10% NaCl solution as an extraction solution, setting the extraction temperature at $50^{\circ}C$, and holding for 15 minutes to extract the MeHg in marine products. A NaOH solution was selected as a clean-up substitute instead of L-cysteine solution. Overall, 670 samples of marine products were analyzed for total mercury (Hg). Detection levels were in the range of $0.0006{\sim}0.3801{\mu}g/kg$. MeHg was analyzed and compared using the current food code and the proposed method for 49 samples which contained above 0.1 mg/kg of Hg. Detection ranges of methylmercury followed by the Korea Food Code and the proposed method were $75.25(ND{\sim}516.93){\mu}g/kg$ and $142.07(100.14{\sim}244.55){\mu}g/kg$, respectively. The total analytical time of proposed method was reduced by more than 25% compared with the current food code method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.101-114
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• 2012

The physico-chemical characteristics including water temperature, salinity, dissolved oxygen(DO), chemical oxygen demand (COD), chlorophyll-a(Chl. a), suspended particulate matter(SPM) and dissolved inorganic nutrients were investigated in the Garolim Bay, Yellow Sea, Korea in 2010 carried out six times per year at 11 fixed stations by Korea Fisheries Research & Development Institute. The water temperature, salinity, COD, dissolved inorganic nutrients, Chl. a and SPM showed significant difference between surface and bottom water but the other parameters didn't. There were not significant difference between stations. The water temperature showed typical change patterns of the temperate seawater. The annual average of salinity showed more than 31 so that there could not have occurred low saline water. The average of DO from June to August showed over than 3mg/L which showed higher than the below standard value of the hypoxic (oxygen-deficient) water. The average of Chl. a varied $1.68{\mu}g/L$ at surface, $2.38{\mu}g/L$ at bottom layer in June and $1.68{\mu}g/L$ at surface, $1.57{\mu}g/L$ at bottom layer at August. The dissolved inorganic nutrients showed high concentration in February and low concentration in August due to the limitation of the freshwater input in summer and phytoplankton used to the dissolved inorganic nutrients. The ratio of DIN/DIP showed 30.52 at surface and 37.89 at bottom layer in June which was higher than other month. The SPM was 44.15mg/L at bottom layer in February which was the highest value in this study due to the northwest monsoon. Because of the actively water change in the open sea without inflow of freshwater from land in Garolom Bay, there were not occurred low saline water and hypoxic water. thus, this Bay showed good water quality and required to be conserved continuously as important costal area for fisheries.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.158-162
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• 2007

Methicillin-resistant Staphylococcus aureus (MRSA) is one of a major nosocomial pathogen worldwide and the emergence of this strain has become a major clinical problem. This study was performed for 13 hospitals with more than 400 beds in the country by collecting samples including hands and nasal cavities of doctors, nurses, guardians and patients. Also, additional 320 samples of hands and nasal cavities of 160 community resident in different locations and regions were collected. In all of medical environments and community resident, 625 strains of S. aureus were detected. Among 625 strains of S. aureus, 585 strains(93.6%) showed the resistance to at least one kind of antimicrobial and 112 strains (17.9%) showed multi-drug resistance with the resistance to 4 different types of antimicrobial. Total 152 MRSA strains (24.3%) were isolated from medical environment and community resident. In nasal cavity and hand, 49 MRSA (19.4%) and 103 (27.6%) MRSA were isolated, respectively Minimum inhibitory concentration(MIC) test is used to measure for susceptibility of MRSA isolated to oxacillin. At a concentration $16{\mu}g/ml$ of oxacillin, 11 strains were inhibited. 32 strains at $32{\mu}g/ml$, 41 strains at $64{\mu}g/ml$, 3 strains at $128{\mu}g/ml$, 25 stains at $256{\mu}g/ml$ and 40 strains at over $256{\mu}g/ml$ were inhibited. It was considered that medical environment showed higher than livestock and marine environments in MRSA detection rate.

• Journal of Food Hygiene and Safety
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• v.32 no.6
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• pp.477-484
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• 2017

This study was conducted to investigate the content of sulfur dioxide, carotenoids and the degree of contamination of Bacillus cereus in 33 kinds of dried sweet potato from domestic mainly dried agricultural products in Korea. According to the characteristics of dried sweet potato samples, it was classified into four clusters and as a result of analyzing the contents of sulfur dioxide, carotenoids and the degree of contamination B. cereus was no significant difference among the clusters. The detection ranges of residual sulfur dioxide from 33 dried sweet potatoes ranged from 0.38 to 28.16 mg/kg, three cases (9.09%) were detected at the reference level of 10 mg/kg or more. But no samples exceeding 30 mg/kg, the tolerance level of sulfur dioxide in dried sweet potatoes were detected. Since dried sweet potato does not have a standard for carotenoids, when comparing the national and international standards of carotenoids, the range of detection of carotenoids in dried sweet potato was $46{\sim}2,663{\mu}g$/100 g, which was within the reference range of $0{\sim}9,826{\mu}g$/100 g. In principle colonies suspected to be B. cereus in dried sweet potato were not detected. In 7 cases (21.21%), there were detected in the range of 0.05~1.59 log CFU/g but not more than 3 log CFU/g as the reference value. The results of this study are expected to be used as basic data to establish quality standard for dried sweet potatoes. In order to control the quality of dried sweet potatoes in domestic market, raw materials, drying method and packaging after distribution, it is necessary to maintain and maintain the process steadily.