Abstract:Objective Traceability and pathogenetic analysis of two suspected homologous （S. aureus） food poisoning cases.Methods We conducted initial screening of pathogens in collected samples of suspected contaminated food， anal swabs from cases， and environmental swabs using a multiplex PCR kit for foodborne pathogens. The isolation， culture， and identification of pathogenic bacteria were performed according to GB 4789.10—2016 in combination with MALDI-TOF MS. Whole genome sequencing and bioinformatics analysis were performed on the isolates. Broth microdilution method for determining resistance to 15 antimicrobial agents， and ELISA for detecting enterotoxins.Results Both incidents shared a common food exposure history. Incident 1 yielded 12 ST2315-t11687 S. aureus isolates， while Incident 2 yielded 2 ST2315-t11687 and 1 ST398-t2346 isolates. cgSNP analysis showed high homology among ST2315-t11687 isolates from both incidents （SNP differences≤8）， while ST398-t2346 was genetically distant. The ST2315-t11687 strain consistently carries enterotoxin genes sea， sec， and sell. ELISA results showed that some strains were positive for SEA/SEC/SEE （n=9）， a few were positive only for SEA （n=2）， or negative （n=3）. The ST398-t2346 S. aureus strains were negative for both enterotoxin genes and enterotoxin production phenotypically. The ST2315-t11687 strains displayed consistent antimicrobial resistance profiles， being resistant to both penicillin and levofloxacin. Importantly， the ST398-t2346 strains were confirmed as methicillin-resistant S. aureus through detection of the mecA gene and demonstrated resistance to penicillin， oxacillin， and cefoxitin. Virulence gene analysis showed ST2315-t11687 carried the immune evasion cluster （sea-sak-chp-scn） and hemolysin genes （hly/hla， hlb， hld， hlgA， hlgB， hlgC）. ST398-t2346 lacked sea but possessed hemolysins and other immune-modulating virulence factors.Conclusion Both food poisoning incidents were caused by enterotoxigenic S. aureus， with transmission linkage of ST2315-t11687 clone between incidents. The prevalent strain exhibits strong pathogenicity， highlighting the need to enhance surveillance of highly pathogenic S. aureus in foodborne disease monitoring.

Abstract:Objective To understand the genetic diversity and antimicrobial resistance characteristics of Salmonella enterica serovar enteritidis （SE） isolated from foodborne disease surveillance in Sichuan Province from 2020 to 2021， and to compare the consistency between the predicted phenotype of antimicrobial resistance and the results of antimicrobial susceptibility test， so as to provide reference for outbreak warning and antimicrobial resistance prediction based on （Whole genome sequencing，WGS）.Methods A total of 222 strains of SE isolated from foodborne disease surveillance from 2020 to 2021 were analyzed by WGS， the single nucleotide polymorphism （SNP） of the strains were analyzed by snippy， and a phylogenetic tree was constructed. Using ResFinder to annotate determinants and predict antimicrobial resistance. The minimum inhibitory concentration （MIC） of the strains against 15 antibiotics was determined with a micro broth dilution method. Rerults Two hundred and fourteen of 222 strains of SE were Group Ⅱ， 4 strains each in Group Ⅰ and Group Ⅲ. A total of 26 suspected aggregation events were identified， mainly small point source aggregation events. Antimicrobial susceptibility tests showed that Group Ⅰ and Ⅲ of SE were susceptible to all antimicrobials tested. The Group Ⅱ of SE had different resistance to 15 kinds of antibiotics， and about 78.5% were multi-drug resistant. The predicted results for some drugs are highly consistent with the phenotype， except polymyxin.Conclusion SE strains isolated from foodborne disease surveillance in Sichuan Province were mainly belonged to serogroup Ⅱ strains， which were further divided into two dominant types， SC-A and SC-B， and four non-dominant types， with high genetic diversity. SNP typing based on WGS can detect the association and cluster of cases from SE monitoring， and provide a basis for initiating epidemiological investigations. The resistance prediction for most ordinary drug was highly consistent with the phenotype tests， but the resistance prediction of compound drugs containing more than two antibiotics and extraordinary drugs still needs to be optimized.

Abstract:Objective To establish a gas chromatography-tandem mass spectrometry （GC-MS/MS） method for the determination of ethylene oxide and 2-chloroethanol in pasta sauce.Methods The sample was extracted with acetonitrile， cleaned-up by QuEChERS purification agent C18/PSA/MgSO₄ （10/10/60） mg/mL， and determined by GC-MS/MS in multiple reaction detection mode （MRM） and quantified by isotope internal standard curve.Results The linear relationship between ethylene oxide and 2-chloroethanol was good in the concentration range of 10-100 μg/L with R²>0.99， the method limit of detection （LOD） was 0.02 mg/kg， and the limit of quantification （LOQ） was 0.05 mg/kg. The average recoveries of the samples at the three spiked concentration levels of 0.05， 0.10， 0.35 mg/kg were 87.79%-108.46%， and the relative standard deviations （RSDs） were 2.03%-11.79%. The intra-day and inter-day precision were 9.62%-10.09% and 9.40%-11.82%， respectively.Conclusion The method is rapid in analysis， accurate and reliable， and can be used for the determination of ethylene oxide and 2-chloroethanol residues in pasta sauce.

Abstract:Objective To understand and master the infection status and molecular epidemiological characteristics of Cronobacter spp. in diarrhea patients in Wenzhou， and to provide a scientific basis for the prevention and control of foodborne diseases caused by Cronobacter spp. in this region.Methods From 2013 to 2024， stool samples were collected from diarrhea patients with foodborne diseases in Wenzhou and tested for Cronobacter spp. Isolated Cronobacter strains underwent species identification， molecular serotyping， and whole-genome sequencing. Bioinformatics analyses were performed to assess genetic relatedness through cluster analysis， as well as to detect the presence of virulence-associated genes and antimicrobial resistance genes.Results A total 21 strains of Cronobacter spp. were detected in 1 816 samples， with a total isolation rate of 1.16%. In terms age distribution， the proportion of patients aged 18-60 years was 38.10%， and the proportion of patients under 1 year old was 33.33%. In terms of seasonal distribution， the detection rate in spring accounted for 38.10%， and that in summer accounted for 33.33%. Among the isolated strains， there were 14 strains of Cronobacter sakazakii， accounting for 66.67% of the total number of strains. Cronobacter sakazakii could be divided into 4 serotypes and 1 untyped strain， among which Csak O1 was the main serotype； Cronobacter malonaticus was divided into 2 serotypes， with Cmal O2 as the main serotype. After identification， the 21 strains of Cronobacter spp. were divided into 10 ST types and 8 clonal complexes （CC）， among which CC7 and CC4 were the main clonal complexes， and ST4 and ST201 were the main ST types. The gene annotation results of the 21 strains showed that all of them carried 17 genes related to motility， adhesion and invasiveness， etc. In addition， a total of 15 drug resistance genes were screened out， and most of the strains carried 11-14 drug resistance genes.Conclusion In cases of foodborne diarrhea caused by Cronobacter spp. in Wenzhou， attention should be focused on Cronobacter spp. infections in infants. Csak O1 and Cmal O1 are the main serotypes， CC4 and CC7 are the main clonal complexes， and ST4 and ST201 are the main ST types.

Abstract:Objective To analyze the epidemiological characteristics of the occurrence of Salmonella food poisoning in China and to provide a basis for the development of preventive and control measures.Methods Food poisoning events caused by Salmonella were collected and organized in the Public Health Emergency Reporting Management System of China’s Disease Control and Prevention Information System， and analyzed using descriptive epidemiological methods.Results From 2004 to 2019， 460 Salmonella food poisoning incidents were reported nationwide， with 26 732 illnesses and 16 deaths， for a case-fatality rate of 0.06%.A higher number of incidents were reported between May and September， accounting for 63.91% of the total number of incidents；The number of incidents where the traceability of samples was completed and the suspected food was clarified was 57.39%；The largest number of Salmonella-contaminated single food types were meat products， followed by bakery and egg products， which accounted for 22.39%， 8.48% and 5.22% of the total number of incidents， in that order.The provinces with the highest number of reported Salmonella food poisoning incidents nationwide were， in descending order， Yunnan Province， Sichuan Province and Guangdong Province， accounting for 15.87%， 11.09% and 10.65% of the total number of incidents， respectively；The main places where incidents occurred were food service establishments， rural banquets and households， accounting for 47.17%， 26.09%， and 16.09% of the total number of incidents， respectively.Serotyping of Salmonella spp. was completed in 182 incidents， with Salmonella enteritidis （56.04%， 102/182）， Salmonella typhimurium （14.29%， 26/182） and Salmonella Dublin （5.49%， 10/182） being the most frequently detected.Conclusion It is recommended to focus on the risk of Salmonella contamination of meat，bakery，egg foods and their products， strengthen the food safety supervision of rural banquets， hotels and collective canteens，enhance safety publicity， monitoring and early warning， reporting and investigation， and traceability and identification of Salmonella in the summer and fall when the incidence of Salmonella food poisoning is high.

Abstract:Objective To explore the characteristics of organophosphorus pesticide residues in vegetables and the dietary exposure risks for residents in Hubei Province.Methods 2 182 vegetable samples were collected from all 17 cities of Hubei Province to determine their residual levels of organophosphorus pesticides. Combined with the vegetable consumption of residents in Hubei Province， acute and chronic dietary exposure assessments were conducted.Results The overall detection rate of organophosphorus pesticides in vegetables in Hubei Province was 9.67%（211/2 182）， and the exceeding standard rate was 1.42%（31/2 182）. The top three pesticides with exceeding standard rates are chlorpyrifos， isocarbophos， phorate and its oxygen analogues. The top three vegetable varieties with exceeding standard rates are leafy vegetables， bulbs， and fresh beans. The dietary exposure assessment results showed that the acute exposure hazard quotient （aHQ） of triazophos was 23.89， indicating a possible acute exposure risk. The chronic exposure hazard quotient （cHQ） of different organic phosphorus pesticides among residents in Hubei Province was less than 1， and the cumulative exposure hazard index （HI） was less than 1， indicating a lower chronic exposure risk.Conclusion There are cases of illegal use and excessive residues of organophosphorus pesticides in vegetables in Hubei Province. Residents in Hubei Province have a lower risk of chronic exposure to organophosphorus pesticides through vegetables， but there is an acute risk of exposure to triazophos. It is recommended that relevant regulatory departments further strengthen the supervision of organophosphorus pesticides in vegetables.

Abstract:Objective To evaluate the pollution levels of lead， cadmium， mercury， arsenic in animal seafood sold in Tianjin City and dietary exposure risk of people in Tianjin.Methods According to the requirements of the national food contaminants and harmful factors risk monitoring manual， 384 representative samples of commercial animal seafood were collected in supermarkets and farmers’ markets in 16 administrative regions of Tianjin City in 2023. The contents of lead， cadmium， mercury， and arsenic were detected according to the national standard detection method， and the pollution degree was evaluated by the single factor pollution evaluation index （Pi） and metal pollution index （MPI）. Combined with residents dietary intake， the dietary exposure risk of 4 kinds of heavy metals were assessed by point assessment method.Results The median content of the four heavy metals （P₅₀） was cadmium （0.061 mg/kg）， lead （0.022 mg/kg）， methylmercury （0.008 mg/kg）， and inorganic arsenic （0.005 mg/kg）， the difference is statistically significant （P<0.05）. Only cadmium exceeded the standard， with the exceeding rate of 2.08% （8/384）， and the sample varieties exceeding the standard were bivalve shellfish and sea crab. The pollution levels of different aquatic products were different. Pi evaluation results showed that sea crabs had lead and cadmium pollution， and cadmium pollution in bivalve shellfish， while the other varieties were at the normal background level； MPI evaluation results showed that the overall pollution degree of 4 kinds of heavy metals was sea crabs>bivalve shellfish>sea shrimp>sea fish. Point assessment results showed that the average exposure （Exp） of the four heavy metals ranged from 0.19-12.36 μg/（kg·BW）， with the highest cadmium and the lowest inorganic arsenic； The hazard quotients （HQ） for cadmium and methylmercury were 0.49 and 0.04， both less than 1. The margins of exposure （MOE） for lead and inorganic arsenic were 25.83 and 473.68， both greater than 1， all less than 1.Conclusion There is a certain degree of lead and cadmium pollution in the municipal animal seafood sold in Tianjin， but the total dietary exposure level was low， and the edible safety was in the acceptable range.

Abstract:Objective To analyze the media characteristics and communication effects of wild mushroom poisoning short videos on Douyin platform， providing scientific evidence for health content governance on short video platforms and wild mushroom poisoning prevention.Methods Python was used to collect 200 wild mushroom poisoning-related short videos and 200 related comments from Douyin platform for content analysis and one-way ANOVA.Results Regarding source types， self-media dominated （58.16%）， while government institutions accounted for only 1.02%. In terms of video framing， entertainment framing accounted for 78.35%， while health education framing accounted for 18.56%. In comment analysis， joking attitudes accounted for 51.76%， insufficient risk perception accounted for 50%， cognitive errors accounted for 22%， and 39.7% of comments showed consumption tendencies. One-way ANOVA revealed that source type （F=3.456， P=0.032） and risk presentation （F=4.123， P=0.021） had significant effects on communication outcomes.Conclusion Wild mushroom poisoning short videos on Douyin platform exhibit obvious entertainment tendencies， with severely insufficient authoritative sources and evident public risk perception bias. There is an urgent need to strengthen content governance on short video platforms， optimize algorithmic recommendation mechanisms， authoritative institutions must also innovate health communication approaches， effectively strengthening public health literacy and reducing the risk of wild mushroom poisoning.

Abstract:Fermented milks， as an important part of the global traditional diet， is crucial for the development of the industry and international trade. With the increasing demand for product innovation and international trade， fermented milk standards are facing challenges in terms of terminology definition， classification framework， ingredient requirements， and labeling. Based on a review of the development of China’s standards， this paper systematically compares China’s fermented milk standards with those of the Codex Alimentarius Commission， Australia and New Zealand， the United States， Japan， and other international organizations and countries in terms of scope， definition， classification， physicochemical indicators， requirements for fermenting microorganisms， and labeling. It summarizes the common principles followed by different international organizations and countries in terms of requirements for raw materials， processes， and fermenting microorganisms， as well as the differences in product classification， definition， ingredient requirements， use of food additives， requirements for live bacteria count， and labeling requirements. The paper also proposes key technical content that should be focused on in future standardization work. It is recommended to continue monitoring the impact of new raw materials and new products on standards， and to explore ways to optimize the definitions of terms， classifications， and labeling requirements. This will provide an effective safeguard for the improvement of China’s dairy standard system and the promotion of high-quality development in the industry.

Abstract:Objective To conduct an epidemiological investigation on a foodborne disease outbreak caused by consuming beef contaminated with Xylazine during a collective dinner， analyze the causes of contamination， provide reference for handling similar incidents in the future， and provide a basis for proposing targeted prevention and control measures.Methods According to the “Technical Guidelines for Epidemiological Investigation of Food Safety Accidents （2012 Edition）”， a population epidemiological investigation， food hygiene investigation， and laboratory testing were conducted on a suspected foodborne disease outbreak that occurred in a catering service unit in a certain area. Descriptive epidemiology and analytical epidemiology methods were used to organize and analyze the data. EpiInfo 7.1 software was used for chi square test and multivariate logistic regression analysis， and P<0.05 was considered statistically significant.Results As a result， there were a total of 27 cases in this incident， with an incidence rate of 47.37% （27/57）. The main clinical manifestations are dizziness （100.0%）， drowsiness （37.0%）， and bradycardia （37.0%）； The epidemic curve shows point source exposure， and the results of univariate （OR=29.71， 95% CI： 3.56-248.10） and multivariate logistic regression （OR=16.577， 95% CI： 1.307-210.055） studies indicate that the suspicious food is spiced beef； The results of the food hygiene investigation showed that the contamination process was due to the failure to meet the requirements of the veterinary drug rest period， as well as the unauthorized slaughter and excessive slaughter， resulting in raw material contamination； Xylazine was detected in biological specimens， semi-finished food products， retained food samples， and processing environment samples of the cases.Conclusion This incident is a foodborne disease outbreak caused by the consumption of spiced beef contaminated with Xylazine. It is suggested to further increase the training efforts for the “Pharmacopoeia of the People’s Republic of China for Veterinary Drugs” and improve the training effectiveness； Strengthen the supervision of the use of veterinary drugs and strictly implement the regulations on the withdrawal period； Strengthen slaughter supervision and crack down on illegal and indiscriminate slaughter； Further improve the harmless treatment of dead livestock and poultry； Strengthen supervision over the use of veterinary drugs， crack down on illegal slaughtering， and implement the system of obtaining tickets and certificates for raw materials.

Abstract:α-ketoglutarate （AKG），an intermediate of the tricarboxylic acid （TCA） cycle， serves as a key substrate for energy production from carbohydrate， lipid， and amino acid metabolites via the TCA cycle. It functions as a myokine secreted by skeletal muscle in response to exercise， regulating physiological processes including energy metabolism， hypoxia adaptation， inflammatory responses， and antioxidant functions. Current randomized controlled trials （RCT） indicate that supplementation with L-arginine alpha-ketoglutarate （AAKG）， an amino acid salt derivative of AKG， enhances upper-body muscle strength， power， and anaerobic work capacity in athletic populations. However， due to limited study numbers， small sample sizes， and relatively low evidence quality， the validity of these findings remains constrained. Regulatory frameworks currently classify AKG as nutritional ingredients only in the European Union. To support the potential inclusion of AKG or AAKG as nutritional ingredients in China， high-quality， single-factor controlled RCT remain imperative.

Abstract:Objective To analyze the current weight status and self-perception of weight among Chinese adults aged 65 and above using the data from the 2015 China Chronic Disease and Nutrition Surveillance， and to provide basic data for guiding the elderly to correctly judge their weight and scientifically control it.Methods Based on the questionnaire survey and physical examination data of adults aged 65 and above from the 2015 China Chronic Disease and Nutrition Surveillance. The body mass index （BMI） range of 20.0-26.9 kg/m2 proposed in the Chinese Dietary Guidelines （2022） was used to evaluate the nutritional status of the elderly.Results In 2015， the proportion of elderly Chinese with a BMI lower than 20 kg/m2 was 14.6%， with 15.2% for males and 14.1% for females， and 10.2% for urban and 18.0% for rural areas， respectively. The proportion of elderly with a BMI higher than 27 kg/m2 was 17.7%， with 15.1% for males and 20.1% for females， and 22.3% for urban and 14.1% for rural areas， respectively. Among the elderly with a BMI lower than 20 kg/m2， only 40.1% correctly perceived themselves as underweight. Among those with a BMI of 20.0-26.9 kg/m2， 75.4% correctly perceived their weight as normal. Among those with a BMI higher than 27 kg/m2， only 40.1% correctly perceived themselves as overweight/obese.Conclusion Low body weight among the elderly in China remains a concern， especially in rural areas. The accuracy rate of the elderly in judging their own weight status is relatively low， and their awareness of healthy weight needs to be improved.

Abstract:As a broad-spectrum preservative， sodium dehydroacetate（DHA-S） was once used in a variety of foods. However， with the systematic research on its toxic effects， the potential threats to human health posed by DHA-S have been widely recognized globally， and its use has gradually been restricted or prohibited. Incorporating the metabolic kinetics characteristics of DHA-S， the toxic effects of DHA-S， including inducing coagulation disorders， damaging the cardiovascular system， disrupting bone metabolism balance， inducing oxidative damage， increasing antibiotic resistance， disrupting energy metabolism and causing skin allergies， were comprehensively reviewed. Moreover， by analyzing the current application status and developmental trajectory of DHA-S as a food additive both domestically and internationally， the possible safety risks were discussed. The purpose is to improve the safety cognition and risk prevention of DHA-S， and then promote the comprehensive prohibition of the application of DHA-S as a food additive in China.