• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.103-106
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• 2004

To confirm physico-chemical stability of formulated products, this study was conducted under different storage conditions; room temperature and accelerated temperature of $54^{\circ}C$. The tested pesticide formulations were dichlorvos 50% EC, acephate 50% WP, hymexazol 4% DP, thiram 80% WP and isoprothiolane 12% GR. The selected formulations were stored for 10 weeks and 5 years under the given temperature in maximum and contents of active ingredients were also analyzed by GLC or HPLC after each time of storage. The degradation rates of 5 active ingredients under the two conditions showed a similar trend except acephate. Acephate was rapidly decomposed at $54^{\circ}C$ but slowly decomposed at room temperature, and the degradation rate under the accelerated condition was 2.4 to 5-fold higher than that under the room temperature. Consequently, the stability test on active ingredients in pesticide formulations was able to recommend to be carried out under the accelerated condition except acephate. And the physical properties of all formulations tested under two storage conditions were good.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.100-106
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• 2011

This study was conducted to investigate the residue amount of harmful materials on the 113 commercial fruit teas (Gugija, Omija, Sansuyu) in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD, LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 4 samples (Gugija). The mean values of heavy metal contents (mg/kg) were Pb, 0.024; Cd, 0.031; As, 0.010; Hg, 0.003. The measured values of Pb, Cd, As, Hg showed within MRLs. The sulfur dioxides were over MRLs in 4 samples (Gugija). These results will be used to establish on the regulation of commercial fruit teas in Gwangju area.

• Food Science and Preservation
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• v.14 no.2
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• pp.124-130
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• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.123-132
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• 2010

Six populations of the diamondback moth, Plutella xylostella, were collected from the different national areas for resistance and reared in laboratory for two sensitive population. These populations of P. xylostella were examined the developed resistance against commercial products of Bacillus thuringiensis. There were 3 products with B. thuringiensis subsp. kurstaki including Tyuneup$^{(R)}$, Thuricide$^{(R)}$ and Geumulmang$^{(R)}$ and 2 products with B. thuringiensis subsp. aizawai including Tobagi$^{(R)}$ and Scorpion$^{(R)}$. The sensitive population of diamondback moths were provided from National Academy of Agricultural Science (NP) and Highland Agriculture Research Center (GR population) and field populations were caught from 6 different national areas. Resistance against Tyuneup$^{(R)}$ was developed 4.8 and 2.5 times in SP and HS compared with GR population of diamondback moth, respectively. In case of Geumulmang$^{(R)}$, it was developed 9.9 and 6.8 times in SP and NM population compared with NP population, respectively. Otherwise, Tobagi$^{(R)}$ was showed higher resistance in HS than any other population compared with GR population, however, Scorpion$^{(R)}$ that is a same strain with Tobagi$^{(R)}$, was showed only double resistance to SP population. It was supposed that the development of resistance to B. thuringiensis might be caused by the continuous application of the specific commercial product at the specific area. So, we need to use the commercial products of B. thuringiensis in rotation with different B. thuringiensis strains. In the other hand, when HS population with highest resistance were reared in laboratory, their resistance ratio was rapidly dropped to 1.1 times at second generation. We have to examined the resistance mechanism of the diamondback moth to B. thuringiensis strains.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.136-145
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• 2020

This study was conducted to evaluate pesticide residues and foreign metallic matter on a total of 104 powdered agricultural products in Incheon. Residue testing for 373 pesticides was conducted by GC-MS/MS, LC-MS/MS, GC-ECD, GC-NPD and HPLC-UVD. Foreign metallic matter was detected by magnetic rod. As a result pesticide testing, 7 of the 104 products were found to be within the MRL of the pesticides. The detected pesticides were chlorpyrifos, etofenprox, fenoxanil, malathion, permethrin, tebuconazole and tetraconazole. As for foreign metallic matter, 16 samples were above the allowable limits set by Korean regulations. Therefore, the inspection of residual pesticides in raw material, and the removal of foreign metallic matter will require further stringent attention for the safety of powdered agricultural products.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.369-375
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• 2012

Loess-sulfur complex has been widely used as an environmental friendly organic materials for insecticides and fungicides in crop cultivation. However, there are high concerns about skin and eye irritation for farm workers due to the high alkaline properties of loess-sulfur complex. The acute toxicity evaluation was conducted with three samples of loess-sulfur complex in different pH (pH 9, 10, 11) in order to supply the evidentiary data for selecting the optimal product among the test materials. The results of acute oral toxicity using rats showed $LD_{50}$ of over 2,000 mg/kg b.w. for all three samples of loess-sulfur complex. The calculated acute dermal $LD_{50}$ of all tested materials was over 4,000 mg/kg b.w.. The Skin and eye irritation indicated that all tested materials have no irritation. Consequently, it was suggested that loess-sulfur complex be low in acute toxicity at all different pH values (pH 9~11).

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.414-421
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• 1997

HACCP procedures are regarded as essential components of modern safety assurance programs for all forms of food processing and preservation, including irradiation. Control of hazards and classification of hazardous microorganisms and indicator organisms (and related tests) are helpful to establish preventive and practice regulations at each facility. A carefully conceived and well implemented system assure the safety of all products. The HACCP is designed to prevent defects, rather than to detect them as in traditional end-point testing and inspection, as controlling requirements into food formulations, processing parameters and operating practices. This article commentes on some equipments and materials for HACCP system.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.83-90
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• 2010

This study was conducted to investigate the residue amount of harmful materials on the 153 commercial medical herbs in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD, LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 7 samples, and were over MRLs (Maximum Risk Levels) in 2 samples (1.3%). The mean values of heavy metal contents (mg/kg) were Pb, 0.570; Cd, 0.081; As, 0.082; Hg, 0.0093. The measured values of Pb, As, Hg showed within MRLs. The excess samples of MRLs were 3 samples (changchul 2, cheongung 1) on Cd. The sulfur dioxides were over MRLs in 7 samples (4.6%), hwanggi and gugija. These results will be used to establish on the regulation of commercial medical herbs in Gwangju area.

• Journal of Applied Biological Chemistry
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• v.56 no.1
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• pp.53-57
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• 2013

In here, we investigated the quantitative analysis method of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) with liquid chromatography-mass/mass spectrometry (LC-MS/MS) or gas chromatography-MS. Two ways of clean-up process were investigated for LC-MS/MS instrumental analysis of IAA, but both a simple dilution and hydrophile-lipophile balance (HLB) solid phase extraction (SPE) were not met the optimal recovery rates for quantitative analysis. On the other hand, the clean-up method for GC-MS was finally optimized through HLB-SPE from 250-folds diluted sample and methylation with trimethylsilyl chloride in methanol for 4 h. The limit of detection for methyl ester of IAA and IBA were both 1.4 mg/L, and recovery rates showed 93-107% from the concentrated liquid fertilizer.

• Journal of Dairy Science and Biotechnology
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• v.24 no.2
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• pp.55-60
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• 2006

The common recognition which the organic baby foods is compared as safe to baby does not mean there is especially plentiful nutrition in organic product. Because the mineral content of agricultural products is partly influenced by the soil quality, chemical fertilizer may change the mineral contents of the products. In that case, it may result in the possibility of the change of the contents of the agricultural vegetable products. However, the contents and the compositions of vitamin, carbohydrate, protein and fatty acids does not change largely from their original nutrition facts of the organic foods. The most advantage of organic baby foods seems to protect the agricultural products from the possibility of chemical contamination. It must be the most strong desire of all the consumers to provide and to nurse their babies with the high quality of baby foods made from organic food materials which are safe, reliable and healthier. That would also be a sincerely good way for the environment and ecosystem of the world.