• Korean Journal of Pharmacognosy
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• v.51 no.3
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• pp.207-216
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• 2020

The analysis method for qualitative analysis of the screening method that can be performed prior to the quantitative analysis of individual pesticide was reviewed in order to meet the safety standards that are being strengthened in the field of pesticide residue testing of herbal medicines. Among the residual pesticides presented in the Korean Pharmacopoeia, 56 pesticides, excluding 15 pesticides that need to be individually analyzed, were selected for analysis using QuEChERS preprocessing and GC-MS/MS, which are used in the existing agricultural products field. For each pesticide, the detection limit level of 0.001-0.005 mg/kg and the quantitative limit level of 0.002-0.017 mg/kg were confirmed. In the recovery test in which the standard was treated at a concentration of 0.02 mg/kg, it was confirmed that the proportion of pesticides satisfying the recovery of 70-120% was 85.7-96.4% for each herbal medicine, so it was confirmed that it was a level that could be reviewed by the screening method.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.302-311
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• 1995

Benfuresate or oxolinic acid, as an experimental pesticide, was applied to the different textural paddy or upland soil respectively under the field condition and the residual concentrations were determined. Six kinetic models were employed to characterize the best-fit kinetic model describing the residual pattern of benfuresate or oxolinic acid and the $t\frac{1}{2}$ estimated from each model was comparatively assessed. All of the six models explained significantly the residual patterns of the pesticides but the empirical models such as PF, EL, and PB were not recommendable for the $t\frac{1}{2}$ estimation. Among theoretical models, the residual patterns were followed in the orders of the second-order(SO)>first-order(FO)>zero-order(ZO) kinetics, judging from the size and significance of coefficient of determination and standard error. However, the multiple FO model, consisting of the fast and slow decomposition steps, was better than the single FO model for the residual pattern and the $r^2$ in this case became similar to that of SO kinetic model. Thus the multiple FO and SO models were represented as the best fit model of the experimental pesticide. The $t\frac{1}{2}$ of benfuresate estimated from the single FO kinetic model in Weolgog and Cheongwon series was 49 and 63 days, respectively, which were 20 and 13% longer than the respective $t\frac{1}{2}$ from the SO kinetic model. The $t\frac{1}{2}$ of oxolinic acid from the FO model in Yonggye and Ihyeon series were 87 and 51% longer than those from the SO kinetic model, respectively. These results demonstrated that the best-fit model representing the residual pattern of a pesticide and the resultant $t\frac{1}{2}$ might be variable with the kinds of pesticides and the environmental conditions. Therefore it is recommended that the half-life of a pesticide be assessed from the best-fit model rather than from the FO kinetic model uniformly.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.226-234
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• 2010

Foliage residue toxicity experiment was performed against honeybee (Apis mellifera) with bifenthrin, a synthetic pyrethroid insecticide with strong acute contact toxicity and imidacloprid, a neo-nicotinoid insecticide with strong acute oral toxicity to know the honeybee toxicity at the residue level on the leaves of alfalfa and apple. Also, the formulation differences to honeybee toxicity were investigated with WP (2%) and EC (1%) of bifenthrin and WP (10%) and SL (4%) of imidacloprid. Generally, foliage residual toxicity of honeybee and residual amounts of tested insecticides was higher in alfalfa leaves with large leaf area per unit weight than in apple leaves. While on the other hand, the only bifenthrin WP treatment showed higher honeybee toxicity on apple leaves than alfalfa. Although imidacloprid showed higher residue amounts ranged $4.9{\sim}25.4\;mg{\cdot}kg^{-1}$ than bifenthrin ranged $0.6{\sim}12.7\;mg{\cdot}kg^{-1}$ on the leaves, the residual toxicity to honeybee was lower than bifenthrin because of its strong penetration character. In conclusion, the residual toxicity of insecticide to honeybee could be affected by the contact and vaporized toxicity of chemical, the residual amounts on the surface of leaves, and the leaf area per unit weight and formulation differences.

• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.489-495
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• 2023

In this study, we detected the presence of residual pesticides in 341 agricultural products collected from local food outlets in western Gyeonggi Province. Residual pesticides were detected in 105 (30.8%) samples. Six samples exceeded the legal limits for residual pesticides, resulting in a non-compliance rate of 1.8%, which was slightly higher than the average non-compliance rate of 1.4% in the last three years. Among the tested agricultural products, only fruits and vegetables were found to have pesticide residues, with 24 of 34 fruits (a detection rate of 70.6%) and 81 of 277 vegetables (a detection rate of 29.2%) testing positive. In total, 59 types of pesticides, including acetamiprid, which was detected 208 times, were detected and had a detection range of 0.01-2.38 mg/kg. Among the 105 agricultural products containing pesticide residues, a single pesticide was detected in 62 samples (59%) and two or more pesticides were detected in 43 samples (41%). In particular, 14 pesticides were detected in the same sample of peaches; dinotefuran was detected 21 times. Upon examining the toxicity of the detected pesticides, Class III pesticides (moderate toxicity) were detected 44 times (21.2%) and Class IV pesticides (low toxicity) were detected 164 times (78.8%). Class I, II, and III pesticides with fish toxicity were detected 68 (32.7%), 14 (6.7%), and 126 times (60.6%), respectively. Upon examining the exposure to high-frequency pesticide components detected five or more times, the hazard index was found to be ≤2.8%. Accordingly, the hazard of residual pesticides based on dietary intake was deemed insignificant.

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.99-105
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• 1996

An attempt was made to determine the residual distribution of organochlorine and organophosphorus pesticides in the various kinds of Korean tea which were purchased form the maket. The organochlorine pesticides investigated in this study were BHC, DDT and dicofol and the organophoshorus pesticides were diazinon, EPN, fenitrothion and parathion. The pesticide residues were determined by GC-ECD and BHC was detected in all the samples and it's level were ranged from 0.00064 po 0.05995 ppm and it's average was 0.00682 ppm and DDT, dicofol and organophosphorus pesticides were not detected in all samples. The organophophorus pesticides were detected(0.0035∼0.0983 ppm) in raw materials but were not in the manufactured material and it is considered that the largely components of the pesticides is removed by drying and high temperature while the tea was manufactured. The recovery tests of the pesticides gave satisfactory results showing an average yield of 97.6% with organochlorine pesticides and 92.5% with organophoshorus pesticides and the detection limits level were 0.00008 ppm to 0.0010 ppm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.340-360
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• 1982

Because of the continuing rapid increase in pesticide usage in Taiwan, much attention has been focus on pesticide contamination of food and effect of pesticides on human and environmental health. The Plant Protection Center (PPC) conducts safety evaluation of pesticides usee! in Taiwan. The pesticides are classified into different groups based on their acute toxicities. Pesticides which are classified into extremely toxic group are not allow to used on short term crops or the continuously harvest crops. The acute toxicity of pesticides to the beneficial insects are also studied, special attention has been paid to the two predators of rice brown planthopper. 60% of cultivated land in Taiwan are paddy field; therefore, acute fish toxicity was taken into consideration when a pesticide was applied for registration to be used in the paddy. Fish toxicities were evaluated by the dangerous rating value which is the amount of pesticide residue in the field water over the TLM value. Mutagenicity of pesticides was continuously evaluated by using Arne's microbial testing method. Island wide survey of residual levels of pesticides of known pollutants such as chlorinated hydrocarbon . insecticides, mercurial compounds in soil, water and biological samples were carried out constantly. The potential of a new1y Imported esticides to pollute the environment were studied by using model ecosystem. Ecological magnification (EM) of a chemical was calculated from model ecosystem. A chemical was considered as a pollutant when its EM value over 5000. In order to ensure the levels of pesticides residue of the crop within the safety limit. The 'tolerance' of pesticides on different crop groupings were established base on 1) acceptable daily intake value of individual pesticides, 2) average daily consumption of each crop groupings by Chinese person, 3) Actual residues of pesticides. on different crops obtained from supervised trials. Total about 79 pesticides for which the tolerances have been established on different crop groupings. Because the intensive agricultural system was adopted in Taiwan. The phytotoxicity of pesticides to the non-target crops was therefore become one of the important factor in the safety evaluation of pesticide usage. These will include 1) direct injury, 2) injury caused by pesticide polluted irrigation water, 3) injury caused by the pesticide polluted soil, 4) reduction of growth caused by the effect of pesticide on the soil microorganisms. This paper will reviewed all the aspects mentioned in the previous .paragraphs. Most the works have done in Taiwan by the PPC.y the PPC.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.131-139
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• 2023

In this study, we investigated pesticide residue levels in 535 domestically distributed agricultural products in South Korea using multi-residue analysis. Agricultural products from 13 regions, including Seoul, were pretreated using QuEChERS and d-SPE, and subsequently analyzed using LC-MS/MS and GC-MS/MS. Residual pesticides were detected in 288 (53.8%) out of the 535 samples, including 40 of apples, 40 of peppers, 33 of mandarins, 31 of peaches, and 144 other commodities. Furthermore, one sample of Korean cabbage exceeded the permitted maximum residue limit (MRL), diniconazole (0.18 mg/kg), detected at about twice the MRL. In total, 91 types of residual pesticides were detected, including fungicides (42), insecticides (48), and a nematicide. The most frequently detected pesticides were dinotefuran (91), carbendazim (75), tebuconazole (61), and pyraclostrobin (59). Our results showed that continuous monitoring of agricultural products is necessary.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.11-20
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• 2012

As increasing the use of pesticides both in number and amount to boost crop production, consumer concerns over food quality and safety with respect to residual pesticides are also continuously increasing. However, there is still lacking of information that can effectively help to remove residual pesticides in foods. In recent years, contaminant removal by gas (or) glow discharge plasma (GDP) attracts great interests on environmental scientists because of its high removal efficiency and environmental compatibility. It was shown to be effective for the removal of some organophosphorus pesticides, phenols, benzoic acid, dyes, and nitrobenzene on solid substrate or in aqueous solution. This work mainly focuses on the removal of wide range of residual pesticides from fresh fruits and vegetables. As for preliminary study, the experiments were carried out to investigate whether GDP can be used as an effective tool for degrading target pesticides or not. With this objective, 60 selected pesticides drop wised onto glass slides were exposed to two types of GDP, dielectric barrier discharge plasma (DBDP) and low pressure discharge plasma (LPDP), for 5 min. Then, they were washed with 2 mL MeCN which were collected and used for determination of remaining concentration of pesticides using LC-MS/MS. Among selected pesticides, degradation of 18 pesticides (endosulfan-total was counted as one pesticide) by GDP could not be examined because control treatments, which were left in ambient environment, of those pesticides recovered less than 70% or even did not recover. However, majority of tested pesticides (42) were degraded by both types of GDP with satisfactory recovery (>80%) of control sample. Pesticides degradation ranged from 66.88% to 100% were achieved by both types of plasma except clothianidin which degradation in LPDP was 26.9%. The results clearly indicate that both types of gas discharge plasma are promising tools for degrading wide range of pesticides on glass substrate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.902-908
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• 2010

In 2008, we monitored residual pesticides of 15 agricultural products such as rice, corn, pea, chestnut, mandarin, lemon, onion, pineapple, lettuce, chard, sweet potato stalk, burdock, squash, sweet pepper and mushroom. Agricultural commodities were collected from markets in 22 provinces (Seoul, Busan, Incheon, Daegu, Ulsan, Daejeon, Gwangju, Wonju, Pohang, Gumi, Changwon, Gimhae, Suwon, Seongnam, Bucheon, Goyang, Yongin, Cheongju, Cheonan, Jeonju, Yeosu, and Jeju). Total 48 pesticides were analysed by multi-residue method using GC/MS/MS. We analysed 1,064 samples and 34 samples (3.20%) were detected. Sweet potatostalk, burdock, chestnuts, peas, corn, chard, squash, mushroom and onions were found to be free from pesticide residues. 6 other agricultural products did not exceed MRLs (Maximum Residue Limits) by the Korean Food Code. Chloropyrifos and fenobucarb were particularly prevalent and also they were detected over 10 times in this monitoring. Nonetheless, the exposed quantity of the 7 residual pesticides is to be considered relatively safe, compared with the acceptable daily intake (ADI) of residual pesticides.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.360-365
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• 2008

For the screening of residual antibiotics in foods, bioassays and microbiological inhibitor tests are commonly applied. These methods are tested by the various susceptibility of bacteria against different kinds of antibiotics. However, the sensitivity of bioassay is generally insufficient to detect some residual antibiotics at level of interest. This study was performed to investigate the detection limit of variable antibiotics of the bioassay and to improve the sensitivity to some antibiotics. The sensitivity of bioassay using Bacillus megaterium ATCC 9885, B. subtilis ATCC 6633, B. cereus ATCC 11778 and Geobacillus stearothermophilus ATCC 10149 was low in the detection of macrolides, quinolones, chloramphenicol, and monensin. On the contrary, Micrococcus luteus ATCC 9341 showed high sensitivity to macrolides and Escherichia coli ATCC 11303 was highly sensitive to quinolones and aminoglycosides. Consequently, both strains would be useful to improve sensitivity of bioassay with a wide detection range.