• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.222-228
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• 2008

Algal Growth-inhibition tests were conducted with 6 pesticides butachlor GR (5%), butachlor EW (33%), isoprothiolane GR (12%), isoprothiolane EC (40%), diazinon GR (3%) and diazinon EC (34%) to determine their comparative toxicity to three species of freshwater green algae Selenastrum capricornutum, Scenedesmus subspicatus, Chlorella vulgris and one species diatom Nitzschia palea. The test species were exposed to the test pesticide for 72 hours and the toxicity represented $EC_{50}$ value calculated by the reduction in growth rate at 72 hours. The toxicity of EC or EW formulation to green algae and diatom was higher than the toxicity of GR formulation at all test in this study. Also, the toxicity of EC formulation was higher than the toxicity technical pesticide. These results indicate that the types of pesticide formulation may affect on their toxicity on algae and the green alga, S. capricornutum and S. subspicatus were more sensitive than C. vulgris. Also, the sensitivity of the diatom, N. palea showed equal or lower than S. capricornutum, S. subspicatus but more sensitive than C. vulgris.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.264-270
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• 2016

This study was conducted to compare of the pesticide residue amounts in fruit trees applied by different sprayers and spray volumes. Apple tree was used as a sample tree, and speed sprayer, power sprayer and knapsack motorized sprayer were tested. For similar sprayer and spray volume, the concentration of fluquinconazole and flusilazole in apple leaves were obtained respectively, for speed sprayer 8.33 and 2.15 mg/kg, for power sprayer 4.56 and 1.10 mg/kg, and for knapsack 4.55 and 1.12 mg/kg. The results showed that the treatment using speed sprayer had highest efficiency. The pesticide residues in apple leaves sprayed by 3 different spray volumes (560, 336 and 230 L/10a) using speed sprayer were 10.76 mg/kg, 8.32 mg/kg, 6.04 mg/kg on fluqinconazle and 3.04 mg/kg, 2.14 mg/kg and 1.47 mg/kg on flusilazole, respectively, indicating that the higher the volume, the higher the residues. The results from this study can be used as scientific basis for evaluating the field trial data for pesticide registration and the spray volume setting for fruit trees in Korea.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.246-252
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• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.130-137
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• 2020

BACKGROUND: Mefentrifluconazole and triticonazole are the triazole fungicides. The maximum residue levels for agricultural products need to be set up. Therefore, development of the official analytical method for determination of mefentrifluconazole and triticonazole residues from agricultural crops was necessary due to safety management, and then a simultaneous analytical method was developed for the determination of mefentrifluconazole and triticonazole in agricultural crops. METHODS AND RESULTS: Samples were extracted using acetonitrile and purified using dispersive solid phase extraction, and then detected with liquid chromatograph-tandem mass spectrometry (LC-MS/MS). Matrix-matched calibration curves (0.0025-0.25 ㎍/mL) were linear into a sample extract with r²>0.99. For validation, the recovery test was carried out at three fortification levels (LOQ, 10 LOQ and 50 LOQ) from agricultural samples. The results for mefentrifluconazole and triticonazole ranged between 92.3 to 115.3% and 91.4 to 108.5%, respectively and RSD (relative standard deviation) values were also below 6.0%. Furthermore, inter-laboratory was conducted to validate the method. CONCLUSION: All values were corresponded with the criteria ranges requested by both the CODEX (CAC/GL 40-1993, 2003) and MFDS guidelines (2016). Therefore, the proposed method can be used as an official analytical method for determination of mefentrifluconazole and triticonazole (triazole fungicides) in the Republic of Korea.

• Journal of agricultural medicine and community health
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• v.25 no.2
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• pp.245-263
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• 2000

This study was conducted to provide the basic data about the health effects of pesticide exposure among farmers for agricultural health study. We analyzed 412 self-administered questionnaires collected from the male farmers who spray pesticides in Kyoung-ju area, Korea. Survey questions were about chronic symptoms, acute symptoms while pesticide spraying, pesticide intoxication accident, safety rules, protective equipments etc. The correlations among the variables related to pesticide exposure and the factors in acute pesticide poisoning and chronic symptoms of farmers were also analyzed. For chronic symptoms, the prevalence of 'tiredness and languor', 'lumbago', 'nocturia', 'shoulder pain', 'numbness', and, for acute symptoms while pesticide spraying, the experience rate of 'itching sense of skin', 'dizziness/headache', 'fatigue', 'eye glaring' were high compared with other symptoms. For 'experience of intoxication accident by pesticide in family', 7.1% of the subjects experienced the accident and the causes were pesticide spraying, food contamination by pesticide, suicide etc. Among safety rules, 'take a bath after spraying', 'change clothes after spraying' were kept relatively well, and, for protective equipments, hat, boots, mask, gloves, protective clothes(lower) were put on relatively well. The factors associated with acute pesticide poisoning were the extent of keeping safety rules, spraying time, orchard cultivation, agricultural area and spraying days per year etc. And the factors associated with chronic symptoms were acute symptoms while pesticide spraying, agricultural area, farming career, extent of keeping safety rules, extent of agricultural work and the pesticide exposure index etc. From these results, it is suggested that to reduce the health effects by pesticide exposure among farmers, the education to promote to keep safety rules and wear protective equipments, and information services should be recommended. And further studies on the long term health effects of pesticide exposure among farmers are required.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.194-201
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• 2009

To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008${\sim}$7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001${\sim}$0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01${\sim}$7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07${\sim}$3.06 % from Kongju agricultural land to watershed after applied pesticides.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.43-53
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• 2012

In order to monitor the levels of pesticides in environment-friendly stalk and stem vegetables and leafy vegetables selling at markets in Korea. A total of 637 (395 organic agricultural products, 242 pesticide-free agricultural products) samples of 21 stalk and stem vegetables and leafy vegetables were collected twice from markets in July and August 2010 in Korea. Pesticide residues in samples were analyzed by multiresidue method for 240 pesticides using GC-ECD/NPD and HPLC-DAD/FLD. The suspected-pesticides were confirmed with a GC-MSD. As a result of analysis, six pesticides were detected from eight samples, representing a detection rate of 1.3% and amounts of pesticide residues in samples were as follows: alachlor 0.043, chlorfenapyr 0.022-0.324, diazinon 0.024, dicofol 0.009-0.138, dithiopyr 0.008, metolachlor 0.025 mg/kg. Their residue levels were below the MRLs. Estimated daily intakes (EDIs) of the pesticides detected from stalk and stem vegetables and leafy vegetables were less than 25% of their acceptable daily intakes (ADIs), representing that residue levels of the pesticides detected were evaluated as safe for consumption. However, five samples containing pesticide residues were unsuitable environment-friendly products because of pesticides detected more than their 10% MRLs in organic and pesticide-free agricultural products.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.421-428
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• 2008

This study was carried out to elucidate the effects of adjuvants on physicochemical properties and pest control efficacy of pesticide spray solution. Spray droplet sizes of pesticide solution decreased by addition of adjuvants even though its effect varied according to the pesticides. The adhesive effect of pesticides sprayed on target crops by addition of adjuvants varied according to the properties, the application methods, and the spray volume of pesticides. Wash-off of the deposited amount of active ingredients of the solution of tricyclazole WP and fenobucarb EC by simulated rainfall after spraying on rice plants dramatically reduced by adding adjuvants. The retained amount of active ingredients of the pesticides were $1.5{\sim}4.1$ times higher than those without adjuvants when subjected to simulated rainfall 6 hours after spraying. Addition of adjuvants to the propanil EC spray solution enhanced the control efficacy in barnyard grass, Echinocloa crus-galli Beauv. by $8{\sim}30%$, which showed a potential to reduce pesticide use.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.241-246
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• 2016

BACKGROUND: Recently, the widespread distribution of pesticides in the hive has been of concern about pesticide exposure on honeybee (Apis mellifera L.) health. Larval toxicity was adapted to assess the synergistic and antagonistic interaction of cumulative mortality to the honeybee larvae of the four most common pesticides detected in pollen. METHODS AND RESULTS: Acetamiprid($3.0{\mu}l/L$), chlorothalonil ($803.0{\mu}l/L$), coumaphos ($128.0{\mu}l/L$), and tau-fluvalinate ($123.0{\mu}l/L$) were tested in combination; binary, ternary and four component mixture. Larvae were exposed to four pesticides mixed in diet at the average levels detected in pollen. As a result, synthetic toxicity was observed in the binary mixture of acetamiprid with coumaphos. The binary and ternary component mixtures of tested pesticides have mostly demonstrated additive effect in larval bees. The significant antagonistic effects were found in four parings of mixtures including chlorothalonil added to acetamiprid/tau-fluvalinate or acetamiprid/coumaphos/tau-fluvalinate, and tau-fluvalinate added to acetamiprid/chlorothalonil or acetamiprid/coumaphos/chlorothalonil. CONCLUSION: Interactions between combinations of four pesticides showed mostly additive or antagonistic effects in larval bees. Therefore, predicting the larval mortality of pesticides mixtures on the basis of the results of single pesticide may actually overestimate the risk. We suggest that pesticide mixture in pollen be evaluated by adding their toxicity together for complete data on interactions.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.128-144
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• 1996

The usage level of pesticides in Korea reached the relatively high extent of 13 kg a.i./ha for arable land, and therefore, establishment of legal standards on pesticide residues in soil environment has been requested. This paper presents relevant information on soil contamination and proposes tentative standards on 20 pesticides in agricultural, urban and forest soils, respectively, as well as needed background data to support the justification of the standards.