• The Korean Journal of Pesticide Science
• /
• v.18 no.4
• /
• pp.278-295
• /
• 2014

Fast and accurate multi-residue pesticides inspecting method needs in Agro-Fishery Products Inspection Center. So, We tried to seek the optimum method using GC-TOF/MS, GC-ECD, GC-NPD after QuEChERS sample preparation. In GC-TOF/MS, 138 kinds of pesticide were spiked at 0.3 and $0.5{\mu}g/g$for the identification and quantification in lettuce sample. Recoveries of 77 pesticides were between 70 and 130% with RSD (relative standard deviation lower than 20% at $0.3{\mu}g/g$. In GC-ECD, NPD, 146 kinds of pesticide were spiked for the identification and quantification in lettuce. Recoveries of 61 species were between 70 and 130% with lower than 20%. These results indicated that GC-TOF/MS, GC-ECD, NPD analysis with the QuEChERS sample preparation can be partly applied to multi-residue pesticides in vegetables.

• The Korean Journal of Pesticide Science
• /
• v.20 no.2
• /
• pp.104-127
• /
• 2016

A new analytical method has been developed to determine 320 pesticides in apple and rice. The extraction of pesticides was carried out based on QuEChERS sample extraction, and determination was performed using LC-MS/MS and GC-MS/MS. 320 pesticides were selected for experiments. 251 and 110 pesticides among them were analysed by LC-MS/MS and GC-MS/MS, respectively. 41 pesticides of them were analyzed by both GC-MS/MS and LC-MS/MS. Among pesticides analysed by LC, 242 pesticides (96% of total number) in apple and 237 pesticides (94% of total number) in rice showed recoveries in the range of 70~120% with RSD ${\leq}20%$. In case of pesticides analyzed by GC-MS/MS, 103 pesticides (94% of total number) in apple and 83 pesticides (76% of total number) in rice were successfully validated. These results indicated that LC-MS/MS and GC-MS/MS analysis with the QuEChERS sample preparation can be partly applied to multi-residue pesticides in agricultural products.

• Journal of Mushroom
• /
• v.18 no.4
• /
• pp.380-386
• /
• 2020

The study was conducted for the safety evaluation of 320 pesticide residues in 768 Lentinula edodes fruit body samples and 143 L. edodes media samples, which are distributed nationwide in South Korea. The monitoring method was the second of the multi-residue methods in the Korean Food Code. GC-ECD, GC-NPD, and GC-MSD were used as evaluation equipment for analysis. Single-analysis of the target pesticides was performed for mepiquat chloride. Through the analysis of collected L. edodes samples, pesticide residues were detected in total seven cases, including four L. edodes fruit body samples and three L. edodes media samples. The detected pesticide residues were carbendazim, diflubenzuron, fluopyram, and dinotefuran. In this study, carbendazim was detected in three L. edodes fruit body samples and one L. edodes media sample. The detected amount of carbendazim was 0.056, 0.17, 0.043, and 0.09 mg/kg, respectively. The amount of carbendazim in the collected L. edodes samples was detected below the MRLs (maximum residue level). The detected amounts of fluopyram and dinotefuran were 0.068 mg/kg and 0.06 mg/kg, respectively. Two pesticide residues were detected in the medium in one case. Mepiquat chloride was not detected in this study. These results suggested that residual pesticides were detected in a small number of collected L. edodes. However, the PLS for unregistered pesticides MRL was 0.01 ppm; therefore, we have to conduct research on preparing safety standards for mushrooms, including L. edodes.

• The Korean Journal of Pesticide Science
• /
• v.16 no.4
• /
• pp.308-314
• /
• 2012

In order to monitor the residual pesticides in environment friendly agricultural commodities, fruits and fruiting vegetables. Twenty-five agricultural commodities were collected twice in May and August 2011 from nine environment friendly agricultural commodities-selling supermarkets and retail stores located in eight major cities in Korea. The number of each agricultural commodity collected, 555 samples in total, was 152 organic agricultural products, 202 pesticide-free agricultural products and 201 low-pesticide agricultural products. Pesticide residues in samples were analyzed by multiresidue method for 245 pesticides using a GC-ECD/NPD and an HPLC-DAD/FLD and the peaks suspected as pesticides were identified with a GC/MSD. As a result of pesticide residue analysis, three pesticides, bifenthrin, EPN and chlorpyrifos, were detected from four samples including apple, representing a detection rate of 0.72%. The residue levels of the four pesticide-detected samples were less than their maximum residue limits (MRLs) but one pesticide EPN detected from pear exceeded its legible criterion of one twentieth MRL. Estimated daily intakes of the pesticides detected from fruits and fruiting vegetables were less than 0.76% of their maximum permissible intake.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.453-462
• /
• 2011

This study was carried out to survey the residual characteristics of pesticides and assess their safety. Nineteen agricultural commodities, collected from wholesale and traditional markets in Cheongju. Nineteen agricultural commodities including perilla leaves were collected from the markets on October 29th, 2010. Total 240 pesticides which can be analyzed by multiresidue analysis method by GLC and HPLC were monitored and the pesticides detected were confirmed by GC-MSD and LC-MS. Five pesticides, alachlor, bifenthrin, endosulfan, procymidone and triflumizole, were detected from five samples, such as welsh onion, leek and celery in case of wholesale market and perilla leaves and welsh onion in case of traditional market. Detection rate of 13.2% was obtained as a result of pesticide analysis but 2.6% of the pesticides detected exceeded their maximum residue limits. The estimated daily intakes (EDIs) and maximum permissible intakes (MPIs) of the pesticides detected were less than 26% and 0.05% of their acceptable daily intakes (ADIs) respectively, representing that residue levels of the pesticides detected would be safe.

• Korean Journal of Environmental Agriculture
• /
• v.30 no.3
• /
• pp.339-345
• /
• 2011

BACKGROUND: Recently in Korea, the import of agricultural products is rising due to the increasing amount of trade. Unregistered pesticides, allidochlor, propachlor, propham, cycloate, diallate and pebulate are widely used as pesticides for rice cultivation in foreign countries, while they are not registered in Korea. Therefore, the residue amount of imported agri-foods should be verified using the proper official analytical method for each of them that has not registered in Korea. METHODS AND RESULTS: This work was conducted to apply the official method of Korea Food & Drug Administration (KFDA) for determining multi class pesticide multiresidues in agricultural commodities. Brown rice and orange which have different characteristics as a matrix were selected as representative samples for residue analysis. The recoveries of cycloate, diallate and pebulate by GC/MS in fortified brown rice and orange with levels of 0.04~0.4 mg/kg were ranged from 82.8% to 110.3%. The quantification limits of three pesticides in brown rice and orange were 0.04 mg/kg. CONCLUSION: As a result, this method can surely be used as an official method for routine analysis of unregistered pesticides in Korea for imported agri-food.

• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.721-727
• /
• 1998

An analytical method for simultaneous and rapid determination of organophosphorus, organochlorine, carbamate, and pyrethroid pesticides in polished rice was developed. The analysis is performed by gas chromatograph with mass selective detector (GC/MSD) in selected ion monitoring (SIM) mode. Pesticides were extracted from samples with acetone by automated Soxhlet apparatus and this extract was evaporated to dryness for the analysis. The residue was dissolved in hexane, followed by a treatment with a Sep-Pak florisil catridge. Pesticides were positively confirmed by GC/MS, retention times, and ion ratios. This analytical method allows a rapid, reliable, and a good recovery of hydrophilic pesticides. Except far captafol, captan, dichlofluanid and dichlorvos, recoveries of 42 pesticides were over 70%.

• The Korean Journal of Pesticide Science
• /
• v.19 no.2
• /
• pp.81-87
• /
• 2015

The present study was aimed to predict the pre-harvest residue limits (PHRLs) of pyrimethanil (fungicide) and methoxyfenozide (insecticide) in grape, and to estimate their biological half-lives and residual characteristics. The pesticides were sprayed once on grape in two different fields 10 days before harvest. At the end of 0, 1, 2, 3, 5, 7 and 10 days after application, samples were harvested for further analysis. The residual pesticides were extracted with acetonitrile and partitioned with dichloromethane, and the high-performance liquid chromatography with diode array detector (HPLC/DAD) was employed for the residue analysis. The results obtained in the present study show that the limit of detection of both pesticides were found to be $0.01mg\;kg^{-1}$. The recoveries of these pesticides were ranged between 80.6% and 102.5% with coefficient of variation lower than 10%. The biological half-lives of both pesticides were observed in field 1 and field 2 which shows 7.7 and 7.4 days for pyrimethanil and 5.1 and 6.1 days for methoxyfenozide, respectively. Further, the PHRL of pyrimethanil and methoxyfenozide was found to be $8.90mg\;kg^{-1}$ and $5.51mg\;kg^{-1}$, respectively at 10 days before harvest. Consequently, the present study suggests that the residual amounts of both pesticides will be lower than the maximum residue limits (MRLs) when grape is harvested.

• Journal of Environmental Science International
• /
• v.6 no.4
• /
• pp.385-389
• /
• 1997

Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC /ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pegticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azlnphos-methyls. The minimum detectable levels of this analytical method were low(0.021-0.058mg/kg).

• Journal of the Korean Chemical Society
• /
• v.43 no.6
• /
• pp.663-669
• /
• 1999

For determination of separated pesticides by using GC and HPLC, liquid-liquid extraction(LLE) and solid phase extraction(SPE) have been carried out to separate and concentrate the organophophorous pesticides such as Diazinon, Fenitrothion, Phosmet, Phosalon and EPN in environmental water samples. ln determination of pesticides by HPLC/UV, SPE has resulted in higher recovery and more precision than LLE, while in determination of pesticides by GC/FPD, vice versa. HPLC/UV after the pretreatment process of sample by solid phase extraction (SPE-HPLC/UV) has suggested the possibility of determination of pesticides ppb level. ln comparison of detection limit, both SPE-HPLC/UV and LLE-GC/FPD are reasonably suitable for analysis of residue pesticides. ln the respect of the rapidity and the solvent required, SPE-HPLC/UV method has proven to be superior to LLE-GC/FPD.