This study developed a QSAR regression model using the XGBoost machine learning algorithm to predict the acute aquatic toxicity of highly hazardous PCBs. EC50 values for Daphnia magna were obtained from QSAR Toolbox 4.7. Input features consisted of approximately 3,000 molecular descriptors and fingerprints generated from official structure data using RDKit and the Morgan algorithm, excluding mixtures. The dataset was split into training and test sets (7 : 3) based on 500,000 randomized seeds, and the most balanced combination was selected using Kolmogorov-Smirnov and Wilcoxon rank-sum tests. Z-score standardization was applied based on the training set, and the XGBoost model was trained using 5-fold cross-validation with grid search optimization. The final model showed excellent predictive performance (R2 =0.97, RMSE= 0.19). A simplified model using only the top 10 predictive molecular features retained approximately 95% of the original accuracy while improving interpretability and efficiency. The model was applied to 38 PCB compounds lacking EC50 values, and the predicted values showed a statistically similar distribution to the measured group, with only minor differences in a few structural fingerprints. These results demonstrate the applicability of XGBoost-based models for reliable toxicity prediction and offer a promising alternative approach for assessing the environmental risk of untested PCBs.
This study aimed to develop a model for accurately predicting the acute aquatic toxicity (48h- EC50) of chlorine disinfection by-products (DBPs). DBPs have caused environmental risks, but experimental toxicity data are difficult to obtain due to time, cost, and ethical constraints. Therefore, a deep learning model was developed using actual concentration-based data. Toxicity data for 139 aliphatic chlorinated compounds were from the OECD QSAR Toolbox and from aquatic toxicity test results provided by the japan ministry of the environment. Various concentration criteria, including nominal and measured concentrations, were encoded as additional inputs, and EC50 values were augmented via log transformation and structural string modifications to overcome small data limitations. The directed message passing neural network (D-MPNN) model, which considers bond directionality, was applied to reflect structural complexity accurately. Also, this model effectively reflected subtle structural differences and showed stable performance even with limited data. Comparisons between models with and without concentration criteria revealed that the model considering all concentration criteria had superior predictive accuracy. This result shows that concentration criteria are a critical factor in toxicity prediction. This study suggests a baseline model that works reliably even with small datasets reflecting realistic concentration criteria, showing its potential use for replacing some experiments and for screening toxic substances.
In this study, chemicals with acute toxicity experimental data were selected as research subjects, and compareed the model derived from statistical analysis and QSAR open-source programs. The physical and chemical properties, dynamic behaviors, and toxicological estimates of the chemicals were calculated using Mordred, a molecular descriptor calculation program based on RDKit. LD50 was set as the toxicity comparison target for each chemical, and independent variables or factors with similarity to independent variables were estimated from the molecular descriptors calculated through Mordred. Molecule descriptors composed of independent variables were compared to predictions from QSAR open-source models, A regression model was created with the selected molecule descriptors and compared with predictions from QSAR programs, confirming high accuracy for specific functional groups. The QSAR model created in this study considers the characteristics and experimental values of each chemical, and provides evidence for selecting variables when constructing toxicity data for machine learning applications.
인삼양영탕은 한국·중국·일본의 전통의약권에서 허약 개 선에 복용되는 14종 한약재로 구성된 의약품이다. 먼저 고 성능 액체 크로마토그래피(HPLC)를 적용하여 인삼양영탕 주요 물질을 규명하였다. 식품의약품안전처 단회투여독성 시험기준에 따라 Sprague-Dawley 랫드 암수 각 5마리에게 0, 1,000, 2,000, 5,000 mg/kg 용량으로 단회 경구 투여하 였다. 시험 결과 사망한 랫드는 없었으며 일반 증상 및 부 검소견에서도 어떠한 이상 반응도 관찰되지 않아, 랫드에 서 인삼양영탕 반수 치사량(LD50)은 5,000 mg/kg 이상으로 판단되었다. 문헌조사를 통해 조사된 인삼양영탕 일반독 성시험 5건(일본 2건, 중국 2건, 한국 1건)에 따르면 개략 치사량(ALD)은 160,000 mg/kg 초과, LD50는 10,000 mg/kg 초과, 최대내성용량(MTD)은 160,000 mg/kg 초과한다고 보 고하였다. 랫드 무독성량 5,000 mg/kg을 기준으로 인체 등 가 용량 변환하면 인삼양영탕 최대안전권장복용량(MRSD) 은 4.1 g 또는 4.8 g이며, 한의서 기준 인삼양영탕 성인 1 일 복용량 28.3 g을 랫드 독성시험 투여 용량으로 변환하 면 34,750 mg/kg 또는 29,100 mg/kg이다. 인삼양영탕 안전 성 평가를 위하여 동물과 인체 종간 등가 용량을 계산하 여 보니, 동물 독성시험 투여 용량과 실제 환자 복용 용 량 간에 유의미한 상관관계가 없음을 시사한다. 학계에서 는 전통적으로 확립된 한약처방 복용량에 대한 동물 독성 시험 평가시에 ICH 및 OECD 기준이외에 다각적인 투여 용량 검토가 필요하다고 사료된다.
The purpose of this study, when predicting acute oral toxicity using QSAR software, the reliability of the predicted values was studied according to a single functional group or multiple functional groups within a single chemical. Acute oral toxicity is predicted using EPA T.E.S.T S/W for chemicals registered in ChemIDplus. The effect of a combination of specific functional periods on the degree of consistency of predicted values was studied. When some specific functional groups (combinations) exist, it was confirmed that the experimental and predicted values were high and low. It was confirmed that the prediction accuracy was high when the Anion group and the Halogen group were together, and the perdiction accuracy was significantly low when the Nitrile group was present. As a result of accumulating such data and showing reliability in predicting acute oral toxicity with EPA T.E.S.T S/W for 10 SVHC substances without experimental values, the matching rate was derived from at least 0% to 73.33%. It was confirmed that there was some tendency of the QSAR prediction value according to the combination of specific complex functional groups. When 10 SVHC substances without experimental data were predicted to be toxic through T.E.S.T S/W by quantitatively databaseizing the above tendency, 0~73.33% of the results were derived as a result of showing the realiability of the program prediction
Baicalin, a flavonoid isolated from Scutellaria baicalensis, has anti-inflammatory, antioxidant, and neuroprotective effects. Glutamate is a major neurotransmitter that plays an important role in brain function, but excessive release of glutamate causes excitotoxicity and damages cells. We investigated the neuroprotective effects of baicalin in glutamate-exposed neurons. The mouse hippocampal neuronal cell line (HT22) was cultured in a general manner, glutamate and/or baicalin were treated on the cells. Baicalin was administered 1 hr before glutamate treatment. Cells were collected 24 hr after glutamate, and cell viability was measured using MTT assay. Reactive oxygen species (ROS) and lipid peroxidation (LPO) assays were performed to measure oxidative stress. Glutamate reduced cell viability in a dose- and time-dependent manner. MTT assay showed that baicalin treatment ameliorated the decrease in cell viability due to glutamate toxicity. The effect of baicalin is dose-dependent. Glutamate caused severe nerve damage, including condensation of the cell shape, loss of dendrites and axons. However, baicalin treatment attenuated these morphological changes, and the effect of baicalin was dose-dependent. ROS and LPO analyses showed that glutamate increases oxidative stress, and baicalin attenuates this change due to glutamate toxicity. The effect of baicalin on these results was dose-dependent. We confirmed that baicalin performs an antioxidant function against glutamate toxicity in neurons. In conclusion, these results suggest that baicalin exerts neuroprotective effects on damaged neurons through antioxidant activity.
This study conducted an acute toxicity assessment using Daphnia magna to evaluate the potential for increased toxicity when pharmaceuticals persist in aquatic environments not as single substances but in mixed forms. In single-substance toxicity tests, the antibiotics clarithromycin and sulfamethoxazole showed EC50 values of 22.3 mg L-1 and 61.05 mg L-1, respectively. However, the EC50 for the mixture of the two substances was determined to be 31.1 mg L-1. Based on these findings, applying the Similar Mode of Action (MOA) equation from the QSAR Toolbox, as recommended by OECD non-testing methods, produced an estimated EC50 of 33.7 mg L-1 for the mixture, showing a difference of 8.5% compared to the experimental value. This study confirms that combined exposure to pharmaceuticals can increase toxicity due to synergistic effects, indicating a significant potential risk to aquatic ecosystems. According to the UN-GHS classification criteria, clarithromycin, sulfamethoxazole, and their mixture were all classified as Category 3, indicating potential toxicity to aquatic organisms. These results emphasize the importance of toxicity assessments that consider interactions between multiple contaminants in real environmental settings, contributing to the development of effective toxicity evaluation and management strategies for the protection of aquatic ecosystems.
아세트아미노펜(acetaminophen, ACT)과 이부프로펜(ibuprofen, IBU)은 수생환경에서 발견되는 대표적인 의약품으로, 다양한 수생생물에서 생물독성영향을 나타내는 것으로 알려져 있으나 이들이 해양생물에 미치는 독성영향은 잘 알려져있지 않다. 이에 본 연구는 ACT 및 IBU가 기수산 물벼룩 Diaphanosoma celebensis에 미치는 급성독성영향 및 해독, 항산화, 탈피 연관 유전자의 발현에 미치는 영향을 조사하였다. 급성독성시험 결과, ACT 및 IBU는 D. celebensis에 상대적으로 낮은 급성독성영향을 나타냈다 (48-h LC50 ACT: 120.72 mg/L 및 48-h LC50 IBU: 212.23 mg/L). 해독효소 유전자의 발현은 ACT 노출 시 모두 유의하게 감소한 반면 IBU 노출 시 Cytochrome P450 (CYP) 360A8, glutathione S-transferease (GST) theta, 및 ATP-binding cassette (ABC) transporter B1 유전자의 발현이 증가하였으며, 이는 ACT 및 IBU가 해독 경로에 미치는 영향이 서로 다를 수 있음을 의미한다. 반면 ACT 및 IBU의 노출은 공통적으로 D. celebensis의 항산화 및 탈피 연관 유전자의 발현을 감소시키는 것으로 나타났다. 본 연구의 결과는, ACT 및 IBU가 서로 다른 작용기전을 통해 대사될 수 있지만, 공통적으로 해양 동물성플랑크톤의 산화환원 항상성과 생식경로에 잠재적인 독성영향을 나타낼 수 있음을 시사한다.
Diethylbenzene (DEB) is a colorless flammable liquid composed of a benzene ring and two ethyl substituents. DEBs mostly exist as a mixture of isomers and are mainly used as intermediates and solvents occupationally. Workers may be exposed to DEB inhalation during their occupational activities including manufacturing or processing of materials; however, limited data are available on the risk assessment of DEB mixtures. In this study, male and female Wistar rats were exposed to vapors of a DEB mixture for 13-weeks (6 hr/day, 5 days/ week) at concentrations of 0, 40, 80, and 160 ppm in a whole-body inhalation chamber. Clinical signs, mean body weight, food consumption, bronchoalveolar lavage fluid (BALF), hematology, blood biochemistry, gross findings, organ weights, and microscopic findings were examined to determine the toxicity of DEB mixture. The exposure concentrations in chambers were 39.48 ± 1.13 ppm, 80.43 ± 2.06 ppm, and 160.20 ± 4.42 ppm for the low, medium, and high dose groups, respectively. No changes related to the test substance were observed, including changes in clinical observation, body weight, food consumption, BALF and blood analysis, necropsy findings, absolute and relative organ weights or histopathological analysis. Based on these results, the NOAEC (no-observed-adverse-effect-concentration) of DEB was defined as 160 ppm under the study conditions.
도모익산(domoic acid) 군 독소는 기억상실성 패류중독 (amnesic shellfish poison, ASP)을 유발하는 해양생물독소 이다. 도모익산은 주로 규조류 Pseudonitzchia sp. 에서 생 성되어 이매패류의 체내에 축적되어 독화된다. 우리나라 연안에서는 봄철과 가을철에 Pseudonitzchia sp.의 출현이 보고되고 있으며, 수산물 내 도모익산 군 독소의 함량 기 준을 설정하여 관리하고 있다. WHO와 EFSA에서는 선제 적 안전관리를 위하여 인체노출안전기준안을 제안하여 관 리하고 있다. 본 연구는 도모익산 군 독소의 이화학적 특 성, 분석법, 인체 노출 사례와 국내외 관리 현황 등의 자 료를 검토하여 도모익산 군 독소의 체계적인 모니터링과 안전관리의 기반을 마련하고자 수행되었다.
Traditional medicine and herbal remedies are gaining popularity worldwide, comprising a significant portion of healthcare research, advancements, and market demand. Growing scientific evidence supports their substantial efficacy as pharmaceutical ingredients and dietary supplements in preventive healthcare. When developing pharmaceuticals, it is crucial to ensure that ingredients are free from side effects and toxicity in order to prioritize safety. Geckos, known as shou gong, are a diverse group of lizards that are widely utilized for treating various diseases in Korean Medicine. This study was conducted to assess the potential acute toxicity of a water extract Gekko gecko by a single oral dose in Sprague-Dawley rats. Twenty rats of each sex were randomly assigned to four groups (5 rats each). Test articles were administrated once by oral gavage to rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg body weight. Mortality, changes of body weight, and clinical signs of gross observation were monitored for 14 days after dosing. At the end of a 14-day observation period, all animals were sacrificed and complete macroscopic and hematological examinations were performed. There was no dead animal or test article-related effect on clinical signs, body weight, or gross finding. Other specific changes were not found between control and treated groups in hematology. Results showed no adverse effect at a dose of 500, 1,000, or 2,000 mg/kg in rats. The minimal lethal dose was considered to be over 2,000 mg/kg body weight in rats.
펩타이드형 독소인 마이크로시스틴(microcystins, MCs) 과 노둘라린(nodularin, NOD)은 남조류라고도 알려진 시 아노박테리아에 의해 생성되는 2차 대사산물로, 독소에 오 염된 물, 토양 및 비료를 사용함으로써 농산물 내에 축적 되고 이를 사람이 섭취함으로써 건강상 위해가 발생할 수 있다. 최근 MCs과 NOD의 농산물 내 오염에 대한 관심 이 대두되며 국내외에서 여러 분석법을 기반으로 농산물 내 오염 수준을 조사하고 있다. 하지만 아직까지 수행된 연구가 많지 않으며, 특히 펩타이드형 독소 중 MCs의 분 석 연구에 치중되어 있거나 오염 취약 지역에서 재배한 농산물이 주로 오염도 조사에 사용되는 등 연구에 한계가 있으므로 MCs과 NOD의 관리를 위해서는 보다 많은 체 계적인 연구가 필요할 것으로 생각된다. 본 연구에서는 체 계적인 모니터링 및 안전관리의 기반을 마련하기 위해 MCs 및 NOD의 이화학적 특성, 독성, 분석법, 오염사례 및 관리현황에 대해 기술하였다.
This study aims to present a performance based design for apartments through evacuation safety assessment and damage impact assessment due to acrylonitrile leakage. In the evacuation safety evaluation, ASET was analyzed as 25 min or more and 60 min or less when the ventilation rate was once per hour, and RSET was 22.6 min. Evacuation safety is satisfied when the number of ventilation per hour is less than 1, so it is necessary to design the number of ventilation to be 1 or less. In the damage impact assessment, the 0% structural collapse rate due to overpressure was measured to be between 71m and 90m, and the 0% fatality rate due to radiant heat was measured to be between 136m and 353m. Therefore, maintain a safe distance of 353m or more.
네오니코티노이드계 농약은 전세계적으로 사용되는 강력한 살충제이지만 환경, 생물에 잔류하 여 악영향을 미치고 있다. 이에 본 연구는 네오니코티노이드계 농약인 imidacloprid와 clothianidin이 공시 작물인 알팔파와 적용작물로 고추와 오이를 선정하여 토양처리 및 경엽처리에 따른 꿀벌 독성과 엽상 잔류 량을 비교하여 기존 엽상잔류독성시험법의 문제점을 확인하고자 하였다. Imidacloprid와 clothianidin을 작 물 또는 토양에 권장량 및 배수로 처리하고 시간에 따른 꿀벌의 치사율에 대한 RT25를 확인하고 잎의 잔류 농약을 HPLC로 측정하였다. 그 결과 경엽처리하였을 때 imidacloprid은 공시작물 RT25가 1일 이하, 잔류 량은 1.07 ~ 19.27 mg/kg이나 적용작물은 RT25가 9일 이하, 잔류량은 1.00 ~ 45.10 mg/kg 수준이었다. clothianidin은 공시작물 RT25가 10일 이하, 잔류량은 0.61 ~ 2.57 mg/kg이나 적용작물은 RT25가 28일 이 하, 잔류량은 0.13 ~ 2.85 mg/kg 수준이었다. 토양처리했을 때 imidacloprid와 clothianidin은 공시작물에 서는 꿀벌에 영향을 미치지 않았으며 잔류량은 0.05 ~ 0.37 mg/kg 수준이었으나, 적용작물에서는 imidacloprid은 RT25가 28일 이하였고 잔류량은 4.47 ~ 130.43 mg/kg 수준이었고, clothianidin은 RT25가 35일 이하였고, 잔류량은 5.96 ~ 42.32 mg/kg 수준이었다. 결론적으로 꿀벌 독성과 엽상 잔류량을 작물간 비교하였을 때 공시작물 보다 적용작물이 꿀벌의 치사율에 많은 영향을 미치고 잔류량도 높게 나타났고, 처리방법에 따라 비교하였을 때 적용작물에 대한 토양처리가 경엽처리에 비해 높은 RT25와 잔류량이 나타 났다. 따라서 농약안전성 확보를 위해 제시된 시험법이 실제 적용작물과 농약 처리방법에 따라 차이가 있 을 수 있어 imidacloprid와 clothianidin의 안전성 평가를 위하여 다양한 경로의 연구가 필요하다.
본 연구는 Symphoricarpos albus(S. albus) 추출물과 발효 추출물을 대상으로 zebrafish 배아를 이용하여 천연 화장품 소재로서의 유효성 평가 및 꼬리지느러미 재생력을 비교 평가하였다. 이를 위한 S. albus 추출물의 항산화 활성은 10-200μg/mL 농도에서 DPPH radical scavenging, FRAP activity, ABTS+ radical scavenging을 진행하였으며, 모두 농도 의존적인 radical 소거 활성을 보이고, S. albus 잎 추출물에 서 가장 높을 항산화 활성을 나타냈다. Zebrafish는 현재 각광받고 있는 실험 대체 동물로서 수많은 화장품 연구에 활용되고 있으며, 본 연구는 zebrafish 배아를 채취하여 응고율, 부화율, 심장 독성을 평가하였다. 그 결과 발효 추출물의 경우 100μg/mL 이상의 농도에서는 독성을 나타내는 것을 확인하였다. 재생 효능 을 평가하기 위해 zebrafish 꼬리지느러미를 절단하였고, 3일 동안 상처 회복력을 관찰하였다. 그 결과 72 시간 부터 S. albus 잎 추출물 200μg/mL에서 대조군 대비 17%의 재생 효과를 나타내었다. 이러한 결과 는 S. albus가 피부 개선용 항산화 및 재생을 위한 천연소재로서 활용 가능한 것으로 사료된다.