• Korean Journal of Environmental Agriculture
• /
• v.15 no.4
• /
• pp.434-441
• /
• 1996

This study was conducted to clarify the degradation pattern, safety evaluation and penetration ratio of benomyl and bitertanol to apple used as postharvest fungicides during CA(controlled atmosphere) and cold storage. In CA storage, the degradation of benomyl and bitertanol in stored apple was slow at the early stage, while that in cold storage was, on the contrary, faster at the early stage. The initial concentrations of benomyl and bitertanol in apples applied at the standard application concentrations were 2.24 and 1.54mg/kg, respectively, and their residual amounts were below the maximum residue limits, 1mg/kg at 135 and 96 days in CA storage, 115 and 70 days in cold storage, respectively. The half-lives of benomyl and bitertanol in stored apples were 124 and 130 days in CA storage, 101 and 111 days in the cold storage, respectively, indicating that the degradation was faster in cold storage than in CA storage. The residual amount of benomyl and bitertanol in stored apples was retained more in peels than in pulps of apples.

• Journal of Environmental Health Sciences
• /
• v.41 no.1
• /
• pp.30-39
• /
• 2015

Objectives: This study was conducted to determine the heavy metal contents in commercial herbal medicines in Korea. Methods: Monitoring of lead, arsenic, cadmium and mercury was carried out on 116 samples of eleven types of herbal medicines. Among the total samples, 71 samples were domestic and 45 were imported. The samples were digested using the microwave method. The heavy metal contents were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and a mercury analyzer. ICP-AES was used to analyze lead, arsenic cadmium. Mercury was analyzed by the amalgamation method. Results: The mean values of the heavy metal contents in the herbal medicines were Pb 0.64mg/kg, As 0.26mg/kg, Cd 0.07mg/kg and Hg 0.004mg/kg. Of the total samples, one violated the MFDS (Ministry of Food and Drug Safety) regulatory guidance on heavy metals in herbal medicines. Lead was detected at more than 5mg/kg in one sample. The measured values of arsenic, cadmium and mercury in the herbal medicines showed levels lower than the recommended levels for herbal medicines in MFDS regulatory guidance. In the comparison of domestic samples with imported herbal medicines, it was found that one domestic sample surpassed the maximum residue limits for lead. Conclusion: These results will be used to establish the regulation and control of heavy metal contents in herbal medicines. In addition, continuous monitoring is needed to ensure confidence in and the safety of these herbal medicines.

• Journal of the Korean Society of Food Culture
• /
• v.35 no.3
• /
• pp.285-293
• /
• 2020

This study was conducted to monitor the residual pesticides on red pepper powder produced in five regions, which are the major producers of red pepper in Korea, such as Ham-pyeong, An-dong, Yeong-yang, Yeong-gwang, and Cheongyang from 2015 to 2016. Residual pesticides were detected on all samples. Among the 286 pesticides tested, 58 pesticides were detected, with the most frequently detected being chlorfenapyr (93.7%). Twelve types of pesticides (chlorfenapyr, cypermethrin, chlorpyrifos, pyraclostrobin, cyhalothrin, tebuconazole, bifenthrin, deltamethrin, fenvalerate, lufenuron, azoxystrobin, and indoxacarb) were detected in all regions, and 14 types of pesticides were used only in certain regions. An analysis of the residual pesticides showed that none of the pesticides detected exceeded the MRL (Maximum Residue Limits). The Positive List System (PLS) requirements were applied to eight pesticides that had no set MRLs. 0.01 mg/kg (PLS requirements) was exceeded in 12 cases. A comparison of the estimated daily intake (EDI) of pesticides with the acceptable daily intake (ADI) to access their risk revealed %ADI values of 0.001-0.756. Carbofuran showed the highest (0.756%), but most pesticides were below 1%. The results show that residual pesticides in red pepper powder are at safe levels.

• Korean Journal of Veterinary Research
• /
• v.56 no.4
• /
• pp.233-239
• /
• 2016

This study was conducted to analyze penicillin G (PEG), streptomycin (STR) and neomycin (NEO) residues in milk of healthy lactating cows. Milk samples were collected from all four quarters of 12 dairy cows 2−7 days after intramammary infusions of an ointment containing PEG, STR and NEO once (n = 4; group I) or twice (n = 4, group II) daily. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry was used to determine the antibiotic residues in the samples. The correlation coefficient ($r^2$) of the calibration curves for all antibiotics was > 0.999 and the limits of detection and quantification were $0.002-0.005{\mu}g/mL$ and $0.007-0.02{\mu}g/mL$, respectively. Recovery rates were ranged from 75.5 to 92.3%. In group I, PEG, STR and NEO residues were detected in milk at 2, 3 and 2 days post-treatment, respectively, which were below the maximum residue limit (MRL). In group II, PEG, STR and NEO residues were detected in milk at 2, 3 and 3 days post-treatment, respectively, which were bellow the MRL. These results suggest that a 3-day for milk withdrawal period after the ointment treatment might be sufficient for reduction of the antibiotic residues below the MRL.

• Journal of Food Hygiene and Safety
• /
• v.32 no.4
• /
• pp.275-283
• /
• 2017

We inspected contaminations of pesticides in the 3,313 crop samples grown under the standard of Korean Good Agricultural Practices (GAP) between 2014 to 2016 May. According to our inspection, violations by unregistered pesticide contaminations far outweighed those by exceeding maximum residue limits. Most of the crops contaminated with unregistered pesticides were minor vegetable crops, for which far less pesticide products are registered compared to cereal grains and fruits. And in our second study, the pesticide in the sprayer was removed 90% or more, but not totally by serial rinses. From this result, it is assumed that pesticide remained in the rinsed sprayer can be carried over to crops unintentionally. Our study shows that supplying pesticide products evenly to all kinds of crops and allowing unintentional carry-over of unregistered pesticides to a certain extent are solutions to revitalize depressed Korean Good Agricultural Practices.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.1
• /
• pp.69-75
• /
• 2013

Enrofloxacin is a fluoroquinolone antibiotic approved for the treatment of infections in animals. Because of the side effects to consumers of animal products, the maximum residue limits (MRLs) of enrofloxacin in animal tissues for consumption are regulated. In this study, a monoclonal antibody (mAb) against enrofloxacin was prepared and characterized for the development of a direct competitive enzyme-linked immunosorbent assay (ELISA). The obtained mAb, Enro44, was highly specific for enrofloxacin and had a 50% inhibition concentration ($IC_{50}$) of 1.99 ng/ml in a competitive ELISA, and the limit of detection (LOD) was 0.50 ng/ml. The cross-reactivity of the mAb with other quinolones and fluoroquinolones was lower than 0.01%. The subclass of the mAb Enro44 was identified as IgG1. The antigen (Ag)-captured direct competitive ELISA using the mAb Enro44 was tested on different spiked samples, including chicken muscle, cattle milk, and cattle urine, and the assay demonstrated recoveries of 82-112%, 80-125%, and 78-124%, respectively. Furthermore, the quantitation of enrofloxacin obtained from the ELISA and from high-performance liquid chromatography (HPLC) was in good agreement, with the linear regression coefficient between 0.933 and 1.056. The cDNAs encoding a heavy-chain Fd fragment (VH and CH1) and a light chain of the mAb Enro44 were cloned and sequenced. Taken together, the results obtained reveal a potential use of this mAb in an ELISA for the detection of enrofloxacin in food samples. The information of amino acid sequence of this mAb will be useful for further modification and production of the mAb in a bioreactor.

• Korean Journal of Environmental Agriculture
• /
• v.40 no.2
• /
• pp.127-133
• /
• 2021

BACKGROUND: Dithiocarbamte fungicides have been used in crop cultivation for diseases protection and treatment. And cultivated agricultrual products were used as feedstuff, and residual pesticides are likely to be absorbed and transferred to livestock. But the maximum residue limits (MRLs) were not established for dithiocarbate fungicides in livestock products, and thus an analysis method was developed and validated for dithiocarbamate fungicides to establish MRLs. METHODS AND RESULTS: Samples were prepared using CS₂ trap method and detected with UV/VIS spectrophotometer. Calibration line (0.1 ~ 10 ㎍/mL) was linear with r² > 0.99. For validation, the recovery tests were carried out at three fortification levels (MLOQ, 10 MLOQ and 50 MLOQ) from livestock samples (egg, milk, beef, pork, and chicken). The results for mancozeb, propineb, and thiram ranged between 76.8 to 109.6%, 79.4 to 108.8%, and 80.2 to 107.8%, respectively and % RSD (relative standard deviation) values were below 9.5%. Furthermore, inter-laboratory analysis was performed 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). This might be used as an official analytical method for determination of dithiocarbamate fungicides at established MRLs and monitoring.

• Korean Journal of Agricultural Science
• /
• v.48 no.1
• /
• pp.33-43
• /
• 2021

Along with the widespread use of pesticides in the world, concerns over human health impacts are rapidly growing. There is a large body of evidence on the relationship between the exposure to pesticides and the elevated rate of chronic diseases such as different types of cancers, diabetes, neurodegenerative disorders like Parkinson, Alzheimer, and amyotrophic lateral sclerosis (ALS), birth defects, and reproductive disorders. This research assessed the health risk of pesticide residues by the dietary intake of vegetables collected from the agro-based markets of Dhaka, Bangladesh. As some of the banned pesticides were also found in vegetable samples, they may pose a higher risk because of cheaper availability and hence the government of Bangladesh should take strong measures to control these banned pesticides. Five organo phosphorus (chlorpyrifos, parathion, ethion, acephate, fenthion) and two carbamate (carbaryl and carbofuran) pesticide residues were identified in twenty four samples of two common vegetables (tomato and brinjal). The pesticide residues ranged from below a detectable limit (< 0.01) to 0.36 mg·kg^-1. Acephate, chlorpyrifos, ethion, and carbaryl were detected in only one sample, while co-occurrence occurred twice for parathion. Continuous monitoring and strict regulation should be enforced regarding the control of pesticide residues in fresh vegetables and other food commodities in Bangladesh.

• Korean Journal of Environmental Agriculture
• /
• v.42 no.3
• /
• pp.220-230
• /
• 2023

Imidacloprid is a neonicotinoid insecticide widely used for insect control in a variety of crops. The evaluation of imidacloprid total residues in animal feeds derived from crop by-products is required to ensure the safety of livestock products. We performed simultaneous LC/MS/MS analyses of imidacloprid and its metabolites in five different livestock products including beef, pork, chicken, milk and egg from domestic markets. The methods for sample preparation and instrumental analysis were established by modifying QuEChERS method to meet the Codex guidelines. The methods generated 0.0035 mg/kg of the limit of determination (LOD), 0.01 mg/kg of the limit of quantitation (LOQ) and standard calibration linearity with >0.983 of the coefficients of determination (R²). The methods exhibited the recovery values of imidacloprid and its metabolites ranging from 65.66 to 119.27% without any interference between matrices. Imidacloprid total residues in the livestock products were found as values lower than the LOQ and maximum residue limits (MRLs). This study suggests that the methods are successfully applicable for the safety evaluation of imidacloprid total residues in livestock products from domestic markets.

• Journal of Applied Biological Chemistry
• /
• v.59 no.3
• /
• pp.189-201
• /
• 2016

A processing factor (PF) has been used to define the maximum residue limits of pesticide in a variety of processed fruit products. This study summarizes PF by the stage of fruit processing based on JMPR reports from 2010 to 2014. When we compared PF of 19 pesticides in apple products during the processing of washing, drying, canning, juice, sauce, puree and pomace, PF was higher than 1 only in pomace. In the comparison of 21 pesticides during the process of grape (washing, juice, wine and raisin), PF was higher than 1 in raisin. In the comparison of 19 pesticides during the process of orange (juice, oil and marmalade), PF was higher than 1 in oil. When 27 pesticides were compared during the process of tomato (juice, puree and paste), paste showed the highest PF value except pomace. During the process of plum (washing, drying and puree) with 12 pesticides, PF was higher than 1 in drying. The correlation coefficients between physical characteristics of pesticide (fat-solubility and volatility) and PF were statistically significant in the processes of apple juice, orange juice, tomato puree and paste and strawberry jam.