This study was conducted to re-establish the withdrawal time (WT) for ivermectin (IVM) in pigs as part of the introduction of the positive list system (PLS) program. Forty-two healthy pigs were orally administered IVM at doses of 2.4 mg/kg feed (IVM-1, n = 20) and 4.8 mg/kg feed (IVM-2, n = 20) once daily for 7 days. After treatment, tissue samples were collected from four pigs at 1, 3, 5, 7, and 14 days post-administration. Based on a previously established analytical method, residual IVM concentrations in pig tissues were determined using LC-MS/MS. In the IVM-1 group, IVM levels in muscle, liver, kidney, and fat were below the limit of quantification (LOQ) on days 7, 7, 7, and 14 after the final administration, respectively. In the IVM-2 group, IVM levels in muscle, liver, kidney, and fat were below the LOQ on days 7, 14, 7, and 14 after the final administration, respectively. According to the European Medicines Agency guideline on the determination of withdrawal times, the WTs for IVM-1 and IVM-2 in edible pig tissues were established as 8 and 11 days, respectively. In conclusion, the estimated WT of IVM in swine edible tissues was shorter than the currently recommended WT of 14 days for IVM.

This study was conducted to re-establish the withdrawal time (WT) of ivermectin (IVM) in goats in accordance with the implementation of the positive list system (PLS). Thirty-four healthy goats were topically administered IVM at doses of 0.5 mg/kg body weight (BW) (IVM-1, n = 16) or 1.0 mg/kg BW (IVM-2, n = 16) as a single treatment. Tissue samples were collected from four goats at 3, 7, 14, and 28 days post-administration. Residual concentrations of IVM in edible tissues were determined using LC-MS/MS based on a previously validated analytical method. In the IVM-1 group, IVM concentrations in all edible tissues were below the limit of quantification (LOQ) by day 3 post-administration. In the IVM-2 group, IVM concentrations in muscle, liver, kidney, and fat were below the LOQ by days 7, 3, 3, and 7 post-administration, respectively. WTs were estimated in accordance with the European Medicines Agency guideline on the determination of withdrawal periods. The calculated WTs for IVM-1 and IVM-2 were 12 and 19 days, respectively. In conclusion, the estimated WT of IVM in edible goat tissues was shorter than the currently recommended withdrawal period of 28 days.

본 연구는 전국 보건환경연구원 농산물검사소에서 일률 적으로 사용 중인 QuEChERS법의 한계를 극복하고, 농산물 잔류농약 정량 분석의 정확도를 높이기 위한 목적으로, 개 선 방안을 모색하고자 하였다. QuEChERS법은 간편하고 신속한 시료 전처리와 매질 효과 보정이 가능하나, 비의 도적 간섭물질이 포함되어 특히 강한 매질 효과가 존재하 는 시료에서는 정확한 정량이 어려운 문제가 있다. 인천 지역에서 유통되는 9종 농산물(대파, 양파, 고수, 들깻잎, 부추, 풋고추, 미나리, 상추, 근대)을 대상으로 매질 효과 를 평가하였고, SANTE/2020/12830 지침에 근거하여 매질 효과에 따른 세 그룹(soft, medium, strong)으로 분류하였 다. 강한 매질 효과가 나타난 파, 고수, 양파 시료(strong group)에 대해 바탕 매질 농도별(10%, 50%, 90%) 정량값 을 비교하였으며, 매질 효과가 약한 상추 시료와 혼합하 는 방법도 적용하여 매질 효과 저감 여부를 확인하였다. 연구 결과, 용매희석법과 상추 무처리 시료를 이용한 혼 합법 모두, 강한 매질 효과를 보이는 시료의 정량 정확도 가 향상되는 것으로 나타났다. 결론적으로, 용매 희석법과 시료 혼합법 모두, 매질 효과를 완화하는 데 효과적임을 확인하였으며, 이는 신속하고 정확한 잔류농약 부적합 판 정이 요구되는 현장 검사 환경에서 분석 결과의 신뢰도를 높이는 실용적인 대안이 될 수 있음을 제안한다.

This study evaluated the effects of supplementing sawdust medium with 10% (w/w) Korean-style soy sauce residue (KS) and brewed soy sauce residue (BS) on the cultivation of Pleurotus ostreatus. Over 25 days, KS treatment produced mycelial growth comparable to the control, whereas BS treatment showed slower colonization. Fruiting bodies appeared after nine days in the control, ten days with BS, and twelve days with KS, with fresh weights of 146.0 g, 174.8 g, and 89.0 g, respectively, indicating reduced yield with KS and increased yield with BS. In antioxidant assays, DPPH radical scavenging slightly increased from 89.15% in the control to 89.99% with KS and 90.34% with BS. ABTS scavenging was 82.36% in the control, 83.42% with KS, and 75.99% with BS. Total polyphenol content was 64.39 mg AAE/mL in the control, 62.72 mg AAE/mL with KS, and 43.28 mg AAE/mL with BS. In conclusion, KS supports mycelial growth without compromising DPPH-based antioxidant capacity, while BS enhances fruiting body yield but reduces ABTS activity and phenolic content. Both residues show potential as supplementary nutrients in conventional sawdust media.

우리나라에 축산물을 수출한 국가들이 2022년과 2023년 에 제출한 2019-2022년 국가별 잔류물질검사프로그램(NRP) 자료를 바탕으로 축산물 유형별, 국가별로 잔류허용기준 을 위반한 동물용의약품과 환경오염물질의 현황을 분석하 였다. 가장 많이 위반된 잔류물질은 네오마이신 2 4 1건, 페 니실린G 183건, 겐타마이신 151건, 세프티오퍼 113건, 니카 바진 103건 등이였고 축산물별로는 소고기, 돼지고기, 가 금육, 우유, 계란 등의 순서로 나타났다. 잔류 위반이 가 장 많았던 소고기에서는 페니실린G, 세프티오퍼, 플루니신 , 네오마이신, 벤질페니실린, 멜록시캄, 플로르페니콜, 질 파테롤 등 전염병 치료에 사용되는 항생제와 해열제 및 성장 촉진에 사용되는 동물용의약품이 주로 검출되었지만 , 돼지고기에서는 성장촉진을 목적으로 사용되는 락토파민 과 항생제인 독시사이클린, 클로람페니콜, 벤질페니실린, 난드롤론, 티오라실, 스트렙토마이신 및 임신 촉진에 사용 되는 호르몬이 가장 흔하게 검출된 것으로 나타났다. 가 금육에서는 콕시듐증 치료에 사용되는 항생제인 니카바진 이 가장 많이 위반되었으며, 스트렙토마이신, 아미노글리 코사이드 항생제, 벤질페니실린, 독시사이클린 및 기타 항 생제가 그 뒤를 이었다. 동물용의약품의 잔류 위반은 많 은 국가에서 보고되고 있으나, 다이옥신과 PCB와 같은 환 경오염 물질의 잔류는 주로 유럽 국가에서 보고되었다. 국 가별 잔류물질의 차이는 각국에서 사육되는 가축과 사육 관리 방식의 차이에 의한 것으로, 소고기의 잔류 수준이 높은 것은 소는 다른 동물에 비해 질병 발생 시 개체별로 치료되기 때문일 것으로 추정된다. 본 연구 결과는 수입 축산물의 안전성 확보를 위하여 국가별, 축산물별로 중점 적으로 검사가 필요한 물질을 제시함으로써 매년 실시하 는 수입 축산물 잔류물질검사를 보다 과학적이고 효율적 으로 수행할 수 있는 기반을 제공하였다.

This study was conducted to reset the withdrawal time (WT) for amoxicillin (AMX) in pigs as a part of positive list system (PLS) program introduction. Forty-two healthy pigs were orally administered with AMX at doses of 10 mg/kg body weight (BW) (AMX-1, n=20) and 20 mg/kg BW (AMX-2, n=20), twice daily for 5 days, respectively. After the treatment, tissue samples were collected from four pigs at 1, 3, 5, 7 and 14 days post-administration, respectively. Based on a previously established analysis method, residual AMX concentrations in pig tissues were determined using LC-MS/MS. In both AMX-1 and AMX-2 groups, AMX levels in all tissues except fat was below the limit of quantification (LOQ) at one day after the final administration. According to the European Medicines Agency’s guideline on determination of withdrawal periods, the withdrawal periods for AMX-1 and AMX-2 in fat tissue were established as 0 and 2 days, respectively. In conclusion, the estimated WT of AMX in edible tissues of pigs is shorter than the current WT recommendation of 5 days for AMX.

The optimization of pellet fuels composed of rice straw, mustard straw, and sawdust was investigated in the present study to improve their properties and utility. Response surface methodology (RSM) and an artificial neural network (ANN) integrated with a multi-objective genetic algorithm (MOGA) were applied to optimize pellet composition for enhanced heating value and minimized ash, nitrogen, and sulfur content. An optimal blend of 74.40% rice straw, 15.60% mustard straw, and 10% sawdust was identified by RSM. These proportions were closely approximated by the MOGA-ANN model within ±1%, and the results were confirmed through experimental validation. Combustion ion chromatography was also used, to analyze the biomasses and the optimized blend, revealing reduced chloride (4189 mg/kg) and sulfur (2716 mg/kg) levels. These results were validated subsequently through experimental tests, confirming the accuracy of the proposed models. A techno-economic analysis indicated that a generation cost of Rs. 10.71 per unit would be associated with a fully agro-residue-based power plant, while less than Rs. 5.28–Rs. 5.31 would be the cost of generation per unit of electricity observed with 5% biomass co-firing in thermal plants. This study demonstrates that improved fuel quality and economic feasibility for biomass power generation can be achieved through strategic biomass blending and co-firing. These findings demonstrated that the blending of various biomass can be a viable strategy for enhancing the characteristics of pellet fuels on an industrial scale.

Gentamicin is an aminoglycoside antibiotic effective against aerobic gram-negative bacteria and is also used in veterinary medicine, particularly in the swine and bovine industries. However, no gentamicin product is currently approved for treating equine diseases in Korea. The present study aims to examine the time-dependent residue of gentamicin in horses after intravenous injection (IV) via jugular vein. The test product was injected at 6.6 mg/kg BW via jugular vein in nine horses. Blood was collected from the horse's jugular vein at 15 minutes, 30 minutes, 1, 4, 8, 12, 24 and 48 hours after injection. To purify the gentamicin in serum, 100μL of 20 mM HFBA in DW, 100 μL of 30% trichloroacetic acid and 300 μL of 20 mM heptafluorobutyric acid (HFBA) in acetonitrile (ACN) were added to 500 μL of serum and supernatant was applied to LC-MS/MS after centrifugation. LC-MS/MS-8050 analyzed the level of gentamicin in serum with Electrospray ionization (ESI) and multiple reaction monitoring (MRM) positive mode. Gentamicin C1 was 478 m/z and product ions were 322, 157 m/z. Precursor ion of Gentamicin C1a was 450 m/z and product ions were 322, 160 m/z. Precursor ion of Gentamicin C2 and C2a was 464 m/z and product ions were 322, 160 m/z. The LC column was a C18 and mobile phase composed of 20 mM HFBA in 5% ACN and 20 mM HFBA in 50% ACN. The amount of gentamicin was calculated by adding four components of gentamicin (C1, C1a, C2 and C2a). The pharmacokinetic parameters of gentamicin were calculated by the WinNonlin program. The Cmax of gentamicin in horse serum was 93 ± 17 μg/kg and the Tmax was 0.25 ± 0 hours. The T1/2 was 6.41 ± 2.32 hours and the CLt was 0.05 ± 0.01L/hr/kg. The Vd was shown as 0.44 ± 0.13 L/kg and the MRT was 1.98 ± 0.55 hours. In conclusion, our data provides useful pharmacokinetic parameters for gentamicin in horses following IV injection.

In this study, an simultaneous LC-MS/MS multi-residue analytical method was developed and validated for the residues of six neonicotinoid insecticides (acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, and thiamethoxam) in honey. Sample preparation included a combination of QuEChERS extraction kit and liquid-liquid extraction method to effectively extract pesticide components from the honey matrix and optimized analytical conditions to achieve high sensitivity and selectivity. The limits of detection (LOD) and the limits of quantitation (LOQ) were set in the range of 6-15 ng/mL and 19-44 ng/mL, respectively and the correlation coefficient (R²) was greater than 0.99, confirming good linearity. In addition, the intra-day recoveries for each pesticide were 75-104%, and the coefficient of variation (CV) was less than 20%, which met the guideline recommended by the Ministry of Food and Drug Safety. The LC-MS/MS method developed in this study is expected to be used as a multi-residue analysis method for 6 neonicotinoid pesticides in honey.

This study aimed to address the time, cost, and ethical issues associated with traditional animal experiment-based observational methods by utilizing in silico Physiologically Based Pharmacokinetic modeling to predict veterinary drug residues in livestock products and validate them against observational data. Using PK-sim software, we modeled the physiological conditions of pigs to predict the depletion of ceftiofur and spiramycin. We evaluated the ceftiofur (3 mg, 6 mg) and spiramycin models by comparing them with observational data using residuals, MSE, and R-squared values. Specifically, the R-squared values for the ceftiofur models were all negative, indicating poor predictive power. For Ceftiofur (3 mg), the R-squared value was <0 with MSE of 611.3764, and for Ceftiofur (6 mg), it was <0 with MSE of 2447.982, highlighting significant discrepancies. Similar shortcomings were observed in the spiramycin models, with an R-squared value of <0 . These discrepancies can be attributed to inaccuracies in literature data, limited physicochemical data, inadequate consideration of inter-individual differences, mismatches between experimental and model conditions, and limitations of benchmark observational experiments. This underscores the critical importance of enhancing data quality and refining modeling approaches. Future research should focus on validating in silico techniques across diverse animal models and drugs to broaden their applicability in safety assessments. Ultimately, leveraging in silico techniques is crucial for establishing a scientifically robust safety management system for livestock products, overcoming the constraints of current observational experimental methods.

Industrial activities that utilize nuclear technology can cause radioactive contamination in the ecosystems. In particular, cesium (Cs) has problems, such as neurological diseases, when it is exposed and accumulated in the bodies of animals, plants, and humans for a long time. Therefore, the development of simple and economical adsorbents for Cs removal is required. In this study, the surface of petroleum residue pitch was modified using NaClO and it was used to remove Cs from an aqueous solution. Batch experiments and characterization of the modified adsorbent were performed to determine the adsorption mechanism between the adsorbent and Cs. From these results, chemical and monolayer adsorption were found to occur at the carboxyl groups on the adsorbent surface, along with a cation exchange reaction occurred due to the sodium ions on the surface. Through this modification process, the total acidity, including phenolic, lactonic and carboxylic functional groups, was improved to 1.563 mmol/g and the maximum adsorption capacity of Cs for the modified adsorbent was 65.8 mg/g.

From 2020, Korean Animal and Plant Quarantine Agency has reset the withdrawal time (WT) for veterinary drugs typically used in livestock in preparation for the introduction of positive list system (PLS) program in 2024. This study was conducted to reset the MRL for tiamulin (TML) in broiler chickens as a part of PLS program introduction. Forty-eight healthy Ross broiler chickens were orally administered with TML at the concentration of 25 g/L (TML-1, n=24) and 50 g/L (TML-2, n=24) for 5 days through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 1, 2, 3 and 5 days, respectively. According to the previously established analysis method, residual TML concentrations in poultry tissues were determined using LC-MS/MS. In TML-1, TML in all tissues was detected less than LOQ at 2 days after drug treatment. In TML-2, TML in liver and kidney was detected more than LOQ at 2 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal periods of TML-1 and TML-2 in poultry tissues were established to 0 and 2 days, respectively. In conclusion, the estimated WT of TML in poultry tissues is shorter than the current WT recommendation of 5 days for TML in broiler chickens.

In Korea, twenty-nine types of microbial pesticides and thirty-two types of naturally occurring materials and chemicals are exempt from MRL (maximum residue level), and fifty types of active ingredients of pesticides are exempt from establishing the acceptable daily intake (ADI) during the pesticide registration process. Out of these materials, twenty-nine types of microbial pesticides and thirty-two types of naturally occurring materials and chemicals are exempt from MRL. Twenty-seven microorganisms and fifteen chemicals are exempt from both ADI and MRL. The European Union exempts the MRL for 148 active pesticide ingredients, and CODEX suggested sixty-three substances as exempt substances from setting the MRL. In Japan, sixty-five types of pesticide components were exempted from MRL. MRL-exempted substances differed depending on the referenced agency, which is presumed to be due to differences in the types of pesticides approved and the approved usage methods in each country. In most countries, MRL exemptions for pesticides are based on toxicity and exposure assessments, and these substances are composed of substances that have a very low risk to the human body or remain in food and are not exposed to the human body and MRLs are exempted based on GAP (good agricultural practice) approved during the licensing process. By referring to the CODEX and the European Union's MRL exemption guidelines, a guideline for evaluating pesticide safety was prepared to determine it as an MRL-exempt substance when setting standards for pesticide residue in Korea. Conclusively, most regulatory agencies decide whether to exempt pesticides from MRL by considering GAP and indications for use during the registration process, and criteria for evaluating exemptions include risk factors, possibility of human exposure and management options.

This study was conducted to reset the maximum residue limit (MRL) for didecyldimethylammonium chloride (DDAC) in broiler chickens. The disinfectant containing DDAC (10%, w/w) was diluted 160 times and evenly sprayed on the bodies of twenty-four broiler chickens at a rate of 15 mL per day per bird for 7 days. After the disinfectant treatment, tissue samples were collected from six broiler chickens at 0.25, 1, 3 and 5 days, respectively. Residual DDAC concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 2.0~10.0 μg/kg), recoveries (86.9~118.6%), and coefficient of variations (<19.98%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In all tissues except for liver, DDAC was detected more than LOQ at 5 days after the disinfectant treatment. In liver tissues, DDAC was detected more than LOQ at 3 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal period of DDAC in poultry tissues was established to 26 days. In conclusion, the developed analytical method is sensitive and reliable for detecting DDAC in poultry tissues. When DDAC disinfectant is sprayed on a poultry house in the presence of broiler chickens, it is necessary to keep the disinfectant from contacting the body of the livestock.

This study compared the physicochemical properties of soybean curd residue and black soybean curd residue produced by hot air-drying and freeze-drying. Regardless of drying method, the crude protein, crude ash, crude fiber contents, pH, L, a, b color values and water soluble index were higher in soybean curd residue, whereas total polyphenol contents and antioxidant activity were higher in black soybean curd residue. Significant differences in water absorption index, oil absorption capacity and emulsion activity were observed between soybean curd residue and black soybean curd residue in freeze-drying. On the other hand, the emulsion stability was not significant difference in both hot-air drying and freezedrying. The crude protein and crude fiber contents of soybean curd residue were not significant difference between hot-air drying and freeze-drying. Freeze-drying resulted in higher crude ash contents, pH, water absorption index, water soluble index, oil absorption capacity, emulsion activity and emulsion stability than hot-air drying. Hot-air drying have caused significantly higher water contents, water activity, total polyphenol contents and antioxidant activity in soybean curd residue than freeze-drying. In conclusion, soybean type and drying methods affect the physicochemical and quality characteristics of soybean curd residue, which could be important factors in the manufacture of processed foods.

This study investigated ethopabate (EPB) residues in edible tissues of broiler chickens given in drinking water and established the withdrawal time (WT) of EPB in poultry tissues. Twenty-four healthy Ross broiler chickens were orally administered with EPB at the concentration of 3.8 mg/L for 14 days (EPB-1, n=24) and 15.2 mg/L for 7 days (EPB-2, n=24) through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 0, 1, 3, and 5 days, respectively. EPB residue concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient values ranged from 0.9980 to 0.9998, and the limits of detection and quantification (LOQ) were 0.03~0.09 and 0.1~0.3 μg/kg, respectively. Mean recoveries in muscle, liver, kidney and skin/fat tissues were 95.9~109.8, 108.7~115.3, 89.9~96.6 and 86.7~96.8%, respectively, and coefficient of variations were less than 17.11%. At the end of the drug-administration period (0 day), EPB was detected at levels under the LOQ in all tissues from both the EPB-1 and EPB-2 groups. According to the results of EPB residue in Ross broiler tissues, withdrawal periods of both EPB-1 and EPB-2 in poultry tissues were established to 0 day. In conclusion, the developed analytical method is suitable for the detection of EPB in poultry tissues, and the estimated WT of EPB in poultry tissues will contribute to ensuring the safety of Ross broiler chickens.