Abstract:Objective To compare the differences of five different ultraviolet light （UV） devices in killing Bacillus subtilis and degrading nucleic acids .Methods The Bacillus subtilis suspensions with same concentration were placed 5 cm away from the lamp sources and irradiated by the biosafety cabinet UV lamp， 185 ozone producing ultraviolet lamp， BKS-UV2016 household ultraviolet lamp， JT8-Y30W ultraviolet lamp and deep UVC-LED for 1 min， 30 s， 10 s， and 5 s， respectively. Culture CFUs （Clone Forming Unit） were compared After 24 hours. Bacterial genome and PCR products were placed 5 cm from the lamp sources and irradiated for 1 minute by the five UV devices mentioned above. The PCR results were compared to analyse the template concentration difference. If the device degrade nucleic acids， the irradiation time was reduced to further analyze the device.Results In killing Bacillus subtilis experiment， five UV devices could kill the bacteria after irradiation for 1 minute， but deep UVC-LED had the strongest killing effect when the time was reduced. In bacterial genome and PCR product degradation experiments， only deep UVC-LED showed degradation， and the effect weakens with the decrease of irradiation time and concentration gradually.Conclusion Deep UVC-LED has a stronger killing effect on Bacillus subtilis in short time，and the device can degrade nucleic acids to solve some PCR pollution problems.

Abstract:Objective Macro-genomics technology was applied to explore the changes in microbial community structure and diversity on the surface of chilled pork at different stages and to analyze the composition and changes of risky bacteria， to provide a reference for the control of risky bacteria in chilled meat.Methods Macro-genomics technology was used to perform sequencing on 30 chilled pork samples at three stages： pre-cooling， post-mortem ageing， and marketing， and to analyze changes in microbial diversity and metabolic pathways of the flora.Results There were significant differences in the flora structure of chilled pork at different stages. From pre-cooling to acid excretion to marketing， the relative abundance of Rhizobium caused an increase and then a decrease in the relative abundance of Proteobacteria. The increase in the abundance of Brochothrix caused a gradual increase in the abundance of Firmicutes. The PCoA analysis showed that the acid-drainage pork partially overlapped with the commercially available pork， suggesting that the bacteria were similar. The relative abundance of the dominant spoilage bacteria， Brochothrix thermosphacta， Pseudomonas fragi， and Acinetobacter baumannii， was significantly increased in the samples from acid-expelled to commercially available meat. Metabolic pathway analyses indicated that the abundance of genes encoding bacteria related to metabolism annotated in the acid-expelled meat samples was the highest among the three stages of samples， the abundance of some of the proteins and enzymes that coordinate sugar metabolism and amino acid metabolism showed an increasing trend in the three groups of samples， and there was consistency with the trend of changes in Brochothrix and Pseudomonas.Conclusion The bacterial populations in the samples of aged meat were similar to those in the samples of saled meat， and the control of bacterial populations during post-mortem ageing should be strengthened during production， while appropriate measures should be taken to control the propagation of spoilage bacteria， to guarantee the quality and safety of meat in the process of supply chain.

Abstract:Objective To trace the pathogenic cause of a foodborne disease outbreak case occurred in a primary school in Nanjing City and analyze the pathogen characteristics and molecular epidemiological relationship， providing reference data for the source tracing and management of foodborne disease outbreaks.Methods A total of 47 foodborne disease outbreak related samples were collected. DNA nucleic acids of all the samples were extracted and performed by Real-time PCR to detect the foodborne pathogens and diarrheal viruses， while the routine bacterial isolation and culture methods were used to isolate and identify pathogenic bacteria. Drug susceptibility testing was conducted with the broth microdilution method. The isolated strains were subjected to whole genome sequencing （WGS） and further pathogenicity prediction and cogMLST analysis.Results Thirty samples were detected Cronobacter spp. nucleic acid positive， and all the other common foodborne pathogenic bacteria and diarrhea virus nucleic acids were negative. Nine Cronobacter spp. isolates （BQ1~BQ9） were obtained， including 6 anal swabs from patients， 2 anal swabs from the staff of the catering enterprise and 1 food retention sample. The drug resistance spectra of the 9 strains were basically the same. Online PathogenFinder predicted that all 9 strains have a high probability of pathogenicity. MLST typing showed 5 different ST types， and the BQ3， BQ4 and BQ9 strains belong to ST8 type. The cogMLST analysis found that BQ3 isolated from a patient anal swab and BQ9 isolated from a food retention sample were clustered tightly， and performed only 2 ST sites differences， indicating these two isolate were highly homologous.Conclusion Cronobacter spp. strains were isolated from this foodborne disease outbreak case and molecular epidemiological analysis showed that the strains from food retention sample and one patient anal swab were highly homologous. Although Cronobacter spp. is generally considered to be an opportunistic pathogen affecting infants and immunocompromised populations， the data from this study suggest that Cronobacter spp. has a high potential as a causative agent of acute gastroenteritis in healthy adults and adolescents， and its risk in foodborne diseases needs to be reevaluated. It is necessary to strengthen the surveillance of Cronobacter spp. in people with foodborne disease and foods other than infant milk powder and complementary foods.

Abstract:Objective To determine vitamin A （VA）， vitamin D （VD） and vitamin E （VE） in formulas for special medical purposes， the online purification-two-dimensional liquid chromatography technique with dual-valve triple-pump center-cutting was established.Methods After the saponification， the samples were introduced into a two-dimensional liquid chromatography system. A PLRP-S column， which was resistant to strong alkaline solutions， was used as an online solid phase extraction column for the clean-up of the sample solution. Subsequently， SPE pumps were reversed to elute the target to the one-dimensional chromatographic system. A perfluorophenyl column was used as the 1D column for the separation of VA and the four VE species. Meanwhile， a C18 column was used as a capture column for VD and a polycyclic aromatic hydrocarbon column was used as a two-dimensional chromatographic column for the separation of VD2 and VD3.Results VA， VD and VE exhibited good linearity within different concentration ranges. The linear ranges were 0.010 0-1.000， 0.001 00-0.100， 0.200-20.0 μg/mL， and the correlation coefficients were all as high as 0.999 9. The limits of detection （LODs） were 4.8， 0.8 and 48 μg/100 g， and the limits of quantification （LOQs） were 12， 2 and 120 μg/100 g. The average recoveries of VA， VD and VE were good with the ranges of 85.9%-114.0%， and the relative standard deviations （RSDs） ranged from 0.6% to 9.2% for the different spiked levels of low， medium and high.Conclusion The method is easy to operate， with high sensitivity and good accuracy， and it is suitable for the routine rapid determination of VA，VD and VE in formulas for special medical purposes.

Abstract:Objective To provide the technical support for precise prevention and control of mushroom poisoning， the species and distribution of wild mushrooms in areas with high incidence of mushroom poisoning in Sichuan Province were understood.Methods Random inspection was used to collect samples in some areas of Mianyang， Yibin， and Ganzi Tibetan Autonomous Prefecture. Molecular biology methods combined with morphological characteristics were used. The ITS sequence of the samples was amplified and identified.Results A total of 364 samples were collected， which were identified as belonging to 39 families， 81 genera， and 215 species. The dominant families included Russulaceae， Agaricaceae， Omphalotaceae， Entolomataceae and Amanitaceae， accounting for 56.74% of the total of species. The dominant genera wre Russula， Lactarius， Amanita etc. accounting for 51.87% of the total species. There were 19 types of poisonous mushrooms， accounting for 8.84% of the total number. The clinical types were mainly acute liver damage， neuropsychiatric， and gastroenteritis. There were differences in the dominant families and genera in different regions.Conclusion Some areas of Sichuan Province have abundant wild mushroom resources. This study provides a foundation for a deeper understanding of the status of wild mushroom resources in Sichuan Province and the prevention and control of wild mushroom poisoning in the future.

Abstract:Objective To investigate the contamination status of aflatoxins （AF） in traditionally-produced vegetable oils in Chongqing and assess the health risk for the population exposed to AF through the consumption of such oil.Methods Samples of traditionally-produced vegetable oils were randomly collected from 39 districts in Chongqing City for AF detection. Based on the dietary data from the 2018 China Health and Nutrition Survey， the simple distributed risk assessment method was applied for dietary exposure assessment. The margin of exposure （MOE） value and quantitative hepatocellular carcinoma （HCC） risk method were used to characterize the risk.Results The detection rate of AF in traditionally-produced vegetable oils was 7.77%， with an average concentration of 0.10-0.48 μg/kg （LB-UB） and zero non-compliance rate. The detection rate of AF in traditionally-produced peanut oil was the highest （22.73%， 5/22.） The average AF exposure level for the whole population in Chongqing City through the consumption of traditionally- produced vegetable oils ranged from 0.069 to 0.319 ng/kg·BW/d （LB-UB）， with a high exposure level （P95） of 0.209~0.967 ng/kg·BW/d （LB-UB）. There was no significant difference in the exposure levels between males and females， but the exposure level of children aged from 2 to 6 years was the highest （0.132~0.610 ng/kg·BW/d） among different age groups. The HCC risk was below 1 case of HCC per （100 000 person-year）， but the MOE values for different genders and age groups were all below 10 000.Conclusion The health risk of HCC caused by exposure to AF in traditionally-produced vegetable oils in the population of Chongqing is relatively low， but there is still potential food safety risk. Continuous monitoring of AF contamination in key foods and efforts to reduce exposure risks for sensitive populations should be prioritized.

Abstract:Objective To assess the health risk exposed to polychlorinated biphenyls （PCBs），the levels of Indicator PCBs in aquatic products in China was investigated.Methods The concentration of seven indicator PCBs （PCB 28， 52， 101， 118， 138， 153， 180） in 100 aquatic products samples，22 species in total，which were collected from 7 major producing provinces in China were analyzed by isotope dilution - gas chromatography-triple quadruped tandem mass spectrometry（GC-MS/MS）.The health risk of Chinese residents exposed to Indicator PCBs through aquatic products was assessed basing on the consumption date of aquatic products in China.Results The concentrations of the seven indicator PCBs （∑₇PCBs） in 22 species aquatic products ranged from 3.62 to 1 755.23 pg/g， which was a low level on a global scale，and all were lower than the maximum limit of aquatic products stipulated in GB 2762—2022.The concentration levels were significantly difference among species，with marine fish and crabs were significantly higher than freshwater fish， shrimp and shellfish （P<0.05）.Through fingerprint characteristics and principal component analysis，it is found that PCB 153 and PCB 138 were the main fingerprint features， and most of the samples had similar sources of contamination. The average daily dose of ∑₇PCBs in aquatic products in the six provinces ranged from 0.02×10^-7 （Liaoning） to 2.40×10^-6 mg/（kg·d） （Zhejiang）， Hazard quotient （HQ） value ranged from 0.01×10^-2 to 1.20×10^-1， and CR value ranged from 0.04×10^-7 to 4.79×10^-6.Conclusion The level and average daily dose of ∑₇PCBs in Chinese aquatic products were low.HQ values were less than 1， indicating low non-carcinogenic risk. At the median pollution level， the carcinogenic risk value of ∑₇PCBs in aquatic products in Fujian Province was 1.79×10^-6， which exceeded 1.0×10^-6， indicating a certain carcinogenic risk.

Abstract:Objective Analysis the use of of dehydroacetic acid （DHA） in rice noodle products and the health risk on consumers in Zhejiang Province. The data will provide support for regulatory policy adjustments and the development of standards by relevant authorities.Methods Rice noodles samples were collected from relevant cities in Zhejiang Province and DHA levels were measured. The dietary intake of DHA was estimated by using the consumption data of rice noodles obtained from the consumption survey. Assessment the daily exposure of DHA in rice noodle consumers.Result Among the 641 samples， DHA was detected in 329 samples （overall detection rate=51.31%）. Among whom， the average level was （280.00±242.69） mg/kg， with P50 and P95 being 218.00 mg/kg and 840.50 mg/kg， respectively. The DHA levels differed significantly across samples from different sources， with those from online stores having the highest level. The average daily exposure of DHA in rice noodles consumers in Zhejiang Province was 0.209 mg/kg·BW， and the high-end exposure level （P95） was 0.512 mg/kg·BW. Since the acceptable daily intake （ADI） value of DHA has not been established， the related health risks cannot be comprehensively evaluated， but the DHA exposure caused by eating rice noodles is warranted further research.Conclusion DHA is widely used in rice noodles products， especially from the online marketing sources. After the implementation of “National Food Safety Standards-Standard for the Use of Food Additives”， preventing the excessive use of dehydroacetic acid will be a key focus of food safety regulation.

Abstract:The health status of infants is an important indicator to measure the social development of a country. Countries around the world have formulated corresponding regulations and standards for infant milk powder in ordinary infant formula and special medical products， but due to the different institutions that promulgate regulations or standards in various countries and have a certain timeline， the requirements for the management of infant formula milk powder in various countries are different. Enterprises need to comply with China’s relevant laws and regulations and standards in production， import and export trade， and avoid conflicts with the relevant regulations and standards of the exporting country. Fourteen infant formula production and sales enterprises and 1 regulatory agency were investigated， more than 30 domestic and foreign regulations and standards for infant formula were collected and analyzed. Technical trade barriers as the main focus， six main differences from labels， clauses， supervision and other aspects were summarized， and corresponding amendments and countermeasure suggestions were put forward， providing reference and reference for Chinese enterprises to carry out production and international trade， promote industry development and government supervision.

Abstract:In recent years， economically motivated adulteration （EMA） and food fraud have occurred frequently， causing serious harm to food safety and food industry. The United States was the first country to propose the concept of EMA and has proposed a series of measures to address it. This article analyzes the definitions of EMA and food fraud， relevant laws and regulations， and measures to deal with food fraud in the United States. By drawing on the experience of the United States in dealing with food fraud， this article analyzes and summarizes the current situation of food fraud in China， and puts forward suggestions for China to deal with these problems.

Abstract:Strengthening the construction of food inspectors is an important guarantee for implementing supervision responsibilities and ensuring food safety. The situation of food inspection team and system construction in China was investigated and sorted out. Various places actively carry out the construction of food inspectors with initial results. There are also challenges： The state has not yet a clear definition of professional food inspectors， local construction standards are different， and supporting systems need to be further improved； The number of middle and senior food inspectors is relatively insufficient， and the specialization level of food inspection team needs to be improved； The training and assessment standards are not uniform， and the strength of teaching staff is weak； The pertinence of inspection needs to be strengthened， and the ability to troubleshoot hidden problems needs to be improved. The construction of a food inspector system with Chinese characteristics is a systematic project， which must rely on existing resources and be carried forward in three dimensions： mechanism， personnel and system. The authority and boundary of food inspection should be clarified， the legal basis is established， and the food inspection system and mechanism is improved； The training assessment standard is unified， the training mode is innovated， the team construction is strengthened； The establishment of security systems can be strengthened such as establishment， salary， rank， funds， and materials， and the space for professional development of food inspectors is broadened.

Abstract:Objective To describe the energy and nutrient intakes of lactating women in 4 urban areas of China， and develop the relationship between them and the weight for length of exclusive breast-fed infants.Methods The dietary of lactating women， body and blood biochemical data of 64 exclusive breast-fed women-infant pairs in 4 urban areas in China were collected using questionnaires， body measurements and blood test. The energy and nutrient intakes of lactating women and the weight for height of infants were calculated and analyzed， and the relationship between them was estimated by using the ordinal multiple classification Logistic regression analysis model.Results Insufficient intake of maternal selenium， vitamin B2 and folic acid is common in 4 cities in China. The Weight for height of infants whose lactating women had low dietary intake of Fe （OR=0.005， 95%CI： 0.000-0.165， P=0.003） and deficiency of serum Vitamin D （OR=0.019， 95%CI： 0.003-0.125， P<0.001） was lower（P<0.05）.Conclusion Multi-nutrient intakes of lactating women in 4 urban areas in China is lower than that recommended by Chinese DRIs， and the weight for height of infants is associated with dietary iron intake and serum vitamin D levels of lactating women. It is suggested to pay attention to the nutritional status of iron during pregnancy and vitamin D during lactation， ensure that the dietary nutritional intake of pregnant and lactating women remains balanced， and promote the growth and development of infants and maternal health.

Abstract:Objective To provide reference for the development of microbial foodborne disease prevention and control strategies， the epidemiological characteristics and spatial aggregation of microbial foodborne disease outbreaks in Guangdong Province from 2011 to 2020 were analyzed.Methods Descriptive analysis was conducted on the outbreak information of microbial foodborne diseases in Guangdong Province from 2011 to 2020. Arcgis 10.8 software was used to analyze the incidence and spatial aggregation.Results From 2011 to 2020， a total of 613 outbreaks of microbial foodborne diseases were reported in Guangdong Province， with a total of 10 716 cases， a total incidence of 9.30/100 000， a total hospitalization rate of 22.14%， and a fatality rate of 0.07%. Cases were mainly concentrated in the Pearl River Delta region， with the highest number of outbreaks reported in 2019， and mainly in the third quarter. The main sources of food were hotels and restaurants （200 cases）， workplace canteens （153 cases） and families （88 cases）. Meat and meat products were the main culprits （141 cases）. Vibrio parahaemolyticus， Salmonella and Staphylococcus aureus were the main pathogenic factors， causing 182， 172 and 85 outbreaks of foodborne diseases， respectively. Improper processing was the main cause of outbreaks， causing 254 foodborne disease outbreaks.The outbreaks of microbial foodborne diseases in Guangdong Province showed regional clustering， and the hot spots were mainly concentrated in Zhuhai City， Zhongshan City， Dongguan City and Shenzhen City.Conclusion Microorganisms foodborne disease outbreaks in Guangdong Province mainly in the Pearl River Delta region of Guangdong Province， Relevant places should emphasis intervention， strengthen the health education of chefs such as key crowd. Specification should be used to minimize microorganisms foodborne disease outbreak occurs.

Abstract:Cronobacter spp. are foodborne opportunistic pathogens known for their significant environmental adaptability and wide-ranging distribution. These organisms have the potential to cause neonatal infections through the contamination of infant powdered formula， resulting in serious diseases， such as necrotizing enterocolitis， sepsis or meningitis， thereby posing a serious threat to the health and life of newborns and premature infants. The recent rapid progress in high-throughput sequencing technology and bacterial genomics has greatly promoted research in areas such as the genomic analysis of Cronobacter， molecular evolution and mechanisms of variation， virulence genes， identification genes， and drug resistance gene mining. These advancements have significant scientific implications for the prevention and treatment of Cronobacter infections. This review aims to offer a thorough analysis of the present status and forthcoming directions in Cronobacter genomics research， providing essential theoretical groundwork for the development of novel approaches in identification， prevention， and treatment of Cronobacter infections.

Abstract:The presence of per- and polyfluoroalkyl substances in food contact paper and paperboard has been drawing attention globally. Accurate and reliable detection results are required for scientific and rigorous risk assessment of their health hazards. This review analyzes the sources of per- and polyfluoroalkyl substances in food contact paper and paperboard， and summarizes the related studies on the two types of tests， migration testing and residue testing， in terms of sample pretreatment， food simulants， migration conditions， extraction solvents and extraction methods. It is expected to provide support for risk assessment and other related work.