Abstract:The history of the establishment of foodborne disease outbreak monitoring system in the United States was introduced and the surveillance data of foodborne disease outbreaks in the United States from 2011 to 2017 were analyzed and compared with that in China. It was found that there were obvious differences in the characteristics of surveillance data of foodborne disease outbreaks between China and the United States in the same period， and microbial pathogenic factors were the main cause of foodborne disease outbreaks. Facing the challenges of global trade integration and post epidemic era of COVID-19， China’s foodborne disease outbreak monitoring system should accelerate the use of new technologies to improve the ability of identification and early warning， and foodborne disease outbreak data results should further play the technical support role in the formulation of relevant food safety management measures in China.

Abstract:Objective To establish a zebrafish larva model for identifying antioxidants and screen candidate substances.Methods Zebrafish larvae with 3 d post fertilization （dpf） were treated with the fish culture water containing 12 known antioxidants， 2 oxidants and 4 candidate substances for 20 h. The maximum tolerant concentration （MTC） was determined by the acute toxic effect including death. With the highest dose of MTC， different dosages of tested substance were used to treat 3dpf larvae respectively， and the reactive oxygen species （ROS） indicator CM-H₂DCFDA was added to the water at the same time. After 20 h treatment， fluorescent density was detected to calculate ROS clearance rate.Results Eleven tested known antioxidants showed lower fluorescent density in treated zebrafish larvae compared to the control， which suggested their ROS clearance potency. Two oxidants increased the fluorescent density， and three of four candidate substances were found to decrease fluorescent density in zebrafish larvae.Conclusion The study provided a sensitive test system for screening candidate antioxidants. The system was used to screen the products developed in the laboratory， and the results showed that it had certain application value.

Abstract:Objective To assess the genotoxicity of Di（2-ethylhexyl） phthalate （DEHP）.Methods A series of guideline-compliant assays were performed to evaluate mutagenicity， chromosomal or DNA damage of DEHP， including Ames test， in vitro mammalian chromosome aberration assay and micronucleus test， comet assay， in vivo mice bone marrow micronucleus assay， and spermatogonial chromosomal aberration test.Results Ames tests results were negative. In in vitro tests， DEHP did not increase the frequency of chromosomal aberration， micronucleus and DNA break except in the dose of 2.5 and 5.0 mg/mL， which significantly increased the frequency of micronucleus and DNA break. In Vitro mammalian cell micronucleus test was negative. The chromosomal aberration rates in mice spermatogonial cells were 1.6%， 1.4%， 1.8%， 2.4% and 3.8% in negative control， 3.75 (24 h)， 7.5 (24 h)， 15 (24 h) and 15 (48 h) mg/kg?BW of DEHP， respectively. There was an increasing trend without statistical significant between groups.Conclusion DEHP showed no obvious genotoxicity under the test conditions.

Abstract:Objective A “multi-integration， effective control， and intelligent guarantee” solution was built for the application scenarios of food safety emergency support for the Winter Olympics.Methods With emergency risk assessment method， the intelligent quick screening device and method for harmful factors in the food supply chain were integrated based on the knowledge map， and big data， artificial intelligence and mobile internet technologies were used to construct an intelligent management and control system for risk early warning of the food supply chain in the Olympics to realize that the emergency plan for different links and different harmful factors in the food supply chain was intelligently generated，which were precisely pushed to users at different levels of the system.Results Using intelligent rapid screening technology and prediction and early warning technology， it has been practical application in the food safety emergency drills for food safety emergencies in the Beijing Winter Olympics and Winter Paralympics （Zhangjiakou Area） 2022， and guarantee of food safety for Olympic food companies in the Winter Olympics test competitions， and the official competitions.Conclusion Taking food safety risk analysis and data governance as the main line， intelligent integration of quick screening technology as a means， and intelligent risk prediction and intelligent early warning interaction as a link， the systematic perception， targeted identification， and accurate verification of harmful factors are promoted in the food supply chain to improve the food safety emergency support capability for major events.

Abstract:Objective To establish the Food Toxicology Database （FoodTox）.Methods A food toxicology database website was established. The priority list of the database was determined. The toxicological data of related substances through literature search was collected， and the systematic literature review （SLR） method was used to sort out the toxicological data of the substances in the library.Results The food toxicology database has collected more than 1 600 substances with related data including toxicology-related information such as metabolism， acute toxicity， genotoxicity， reproductive and developmental toxicity， subchronic toxicity， chronic toxicity and carcinogenicity， population data， health guidance values and regulations of domestic and foreign management， related foods and symptoms etc.， which has been open to researchers in related fields.Conclusion This database will provide the related professionals with the first-hand data， rapid technical support for emergency risk assessment and reference for priority substance evaluation.

Abstract:Objective To provide data basis for improving the accuracy of food safety risk assessment in China， the cooking coefficients of five toxic metals in marine fish was studied.Methods Based on the consumption of 19 kinds of marine fish in Guangdong province， samples were divided into steamed， fried， roasted group and a control group （raw fish）. The concentrations of the total mercury， methyl mercury， arsenic， cadmium and lead were determined before and after the cooking process， and the cooking coefficients of five toxic metals were calculated.Results The concentrations of total mercury， methyl mercury， total arsenic and cadmium in fried and roasted fish were significantly higher than those in control group （P<0.05）， while the concentrations of lead in steamed fish were significantly lower than those in control group （P<0.05）. In addition， the cooking coefficients of heavy metals in different kinds of marine fish were different under the same cooking method， and the coefficients of heavy metals in the fried and roasted group were higher than those in the steamed group.Conclusion The concentrations of total mercury， methyl mercury， total arsenic， cadmium and lead in marine fish can change significantly after cooking. During risk assessment， appropriate processing factors should be selected to improve the accuracy of risk assessment in combination with the needs of the assessment situation.

Abstract:Objective To investigate the distribution and molecular typing characters of Yersinia enterocolitica in food in Wenzhou.Methods After pre-enrichment of samples at 4 ℃， the selective media was used for the isolation and identification of Yersinia enterocolitica from food. The biotype， serotype， virulence genotype， drug resistance and pulsed field gel electrophoresis， （PFGE） molecular typing of the isolated strains were analyzed.Results Among 676 samples in 6 categories， 69 Yersinia enterocolitica strains were isolated from 68 samples， with a positive rate of 10.1% （68/676）. The detection rate of prepared meat products was the highest （20.5%， 9/44）， followed by quick-frozen food （17.2%， 11/64）. Biotype 1A accounted for 95.7% （66/69） of the isolates， and the predominant bioserotype was 1A/O∶5 （29.0%）， followed by 1A/O∶8（14.5%）. 88.4% （61/69） of the strains only harbored ystB gene. Particularly， there was a bioserotype 4/O∶3 strain carried the virulence gene of ail， ystA， yadA and virF. The sensitivity rates of the isolates to 14 kinds of antibiotics were over 94%. Thirty two serotyped strains were divided into 29 PFGE patterns.Conclusion Food was contaminated by Yersinia enterocolitica to some degree in Wenzhou， and the pathogenic strain was detected. The antibiotic resistance rate of Yersinia enterocolitica was at a low level， and PFGE suggested highly genetic polymorphism.

Abstract:Objective To calculate the lower limit of 95% confidence interval of benchmark dose （BMDL） of 3-monochloro-1，2-propanediol （3-MCPD） and its esters for renal tubular hyperplasia effect based on benchmark dose （BMD） method.Methods The data of the most sensitive endpoint of renal tubular hyperplasia in the 2-year chronic toxicity and carcinogenicity study of 3-MCPD were analyzed. BMD model and analysis were used by methods of frequentist， frequentist model averaging and Bayesian model averaging， respectively. Smooth dose response curve was obtained by fitting the nine conventional models， and then the optimal fitting model and BMDL₁₀ estimation value were obtained.Results The best data set was selected by comparing the conservative degree of results across different data sets. Under the same data set， the selection of restricted or non-restricted model parameters， and the selection of single model or model averaging， were key factors to affect the BMDL results of 3-MCPD and its esters. According to model fitting degree and conservative degree， BMDL₁₀ of the most sensitive endpoint of renal tubular hyperplasia of 3-MCPD and its esters was 0.87 mg/kg?BW. The health based guidance value （HBGV） needs to be further determined by the BMDL₁₀ with uncertainty factor.Conclusion The results of this research could be applied for the risk assessment of 3-MCPD and its esters in key foods of China， and further provide scientific advice on the supervision and control of key foods based on the assessment results.

Abstract:Objective The risk assessment model of fatty liver accumulation in zebrafish larvae was established to identify the hepatotoxicity hazards of plasticizer butyl benzyl phthalate （BBP） using Di （2-ethylhexyl） phthalate （DEHP） and dibutyl phthalate （DBP） as positive control samples. This model was used to identify hepatotoxicity of butyl benzyl phthalate （BBP）.Methods The fatty liver signal intensity and expression of peroxisome proliferator activated receptor （PPAR） target gene CD36 in zebrafish liver after DEHP and DBP exposure were analyzed， and the hepatotoxicity model of zebrafish larvae was preliminarily constructed， which was used to evaluated the hepatotoxicity of BBP. In addition， liver density analysis， TG quantitative detection of zebrafish larvae and liver pathological examination of adult zebrafish were used to further verify the reliability of the model. The benchmark dose method （BMD） was used to derive the point of departure.Results DEHP and DBP showed significant risk of fatty liver induction （both P<0.01）， and the relative expression level of CD36 was significantly higher （P<0.001 and P<0.05）， indicating the success of modeling. BBP （0.000 012 5%， 0.000 025%， 0.000 05%） induced significant lipid deposition （P<0.05， P<0.001， P<0.001）， significantly affected liver parenchyma （P<0.05， P<0.01， P<0.01）， increased TG accumulation significantly （P<0.05， P<0.05， P<0.01）， and up-regulated CD36 gene expression. Furthermore， BBP （≥0.000 012 5%） induced the formation of lipid vacuoles in the liver of adult zebrafish， as well as the reduction of vacuolar space and number， suggesting that BBP had significant hepatotoxicity. The key effect was fatty liver signal intensity （S） and the benchmark dose lower-bound confidence limit （BMDL） value was 0.013 mg/L.Conclusion This study successfully established a model of liver fat signal intensity to identify the hepatotoxicity of phthalates in zebrafish larvae， and preliminarily clarified the PPAR target gene CD36 involved in hepatotoxicity， and further provided a scientific basis for the risk assessment of phthalates combined with the BMD.

Abstract:Objective To obtain basic safety data， the systematic toxicology of Scutellaria baicalensis Georgi leaf was studied.Methods The extract of Scutellaria baicalensis Georgi leaf as test substance， the systematic toxicology safety of Scutellaria baicalensis Georgi leaf was evaluated by the national food safety standards of acute oral toxicity， bacterial reverse mutation assay， micronuclear test of mammalian， chromosome aberration test of spermatocyte in mice and 90 day oral toxicity test.Results The LD₅₀ of acute oral toxicity on Scutellaria baicalensis Georgi leaf extract was greater than 20.0 g/kg?BW in male and female mice， simultaneously the LD₅₀ was greater than 15.0 g/kg?BW in male and female rats， which meant actual non-toxic. The detection results of bacterial reverse mutation assay， micronuclear test of mammalian and chromosom aberration test of spermatocyte in mice were negative. The 90 d oral toxicity test showed that compared with the control group， there were no significant differences in the body weight， food intake， food utilization rate， hematology and blood biochemistry in the test groups of 2.0， 4.0， 8.0 g/kg?BW.Conclusion Under the conditions of this experiment， toxic effects of Scutellaria baicalensis Georgi leaf extract on experimental animals were not found. After conversion， the NOAEL value of Scutellaria baicalensis Georgi leaf was 24.0 g/kg?BW.

Abstract:Objective While reviewing the notification of sanitary and phytosanitary （SPS） measures in China in the past 10 years and carrying out relevant research on the notification of SPS measures in China， the shortages in the implementation of SPS notification transparency work were analyzed， and suggestions were put forward for further improving the SPS transparency work， which can provide reference for further strengthening the notification of SPS measures in China and better fulfilling the obligation of transparency.Methods China’s SPS notification from 2012 to 2021 was obtained from the SPS Information Management System developed by the WTO Secretariat. This paper made a statistical analysis on the number of SPS notifications， different types of SPS notifications and notification measures from 2012 to 2021 in China by further collation， summary and translation. And the notification of SPS measures of China’s major trading partners was obtained through the system.Results From 2012 to 2021， China notified the WTO/SPS secretariat of 743 SPS measures， including 736 regular notifications， 5 emergency notifications and 2 supplement notifications. In terms of areas involved， 443 items were notified of SPS national standards on National Food Safety Standards related to food additives.Conclusion China has fulfilled the WTO/SPS transparency obligation， while there are still some problems such as the subsequent changes were not notified in a timely manner. The transparency of WTO/SPS should be further strengthened and improved in the future.

Abstract:Objective A droplet digital polymerase chain reaction （ddPCR） method was developed for the rapid quantitative detection of Listeria monocytogenes in food.Methods Specific primers and probes for Listeria monocytogenes were screened. The constant value effect of ddPCR method and plate counting method was compared through the detection of pure bacterial solution and artificially contaminated samples. The specificity， sensitivity and repeatability of ddPCR method were analyzed.Results The ddPCR had the characteristics of excellent specificity， sensitivity and repeatability in Listeria monocytogenes detection. The limit of detection （LOD） and the limit of quantification （LOQ） in pure bacterial solution were 136 CFU/mL. The LOQ in squid ring and sausage samples was 240 CFU/g and 155 CFU/g. The coefficient of variation of ddPCR was less than 25% at each gradient level， and the relative deviation of the logarithm of ddPCR and plate counting was less than 30%.Conclusion The established ddPCR method is rapid， accurate， sensitive and specific for the quantitative detection of Listeria monocytogenes in food.

Abstract:Objective A rapid method for determination of histamine and tyramine in milk was designed and studied by azo dye-spectroscopy.Methods Histamine and tyramine in samples were extracted by hydrochloric acid solution， and dyed reaction was acted with azo reagent. Spectral method was used for detection within 10-15 min. External standard method was used for qualitative and quantitative analysis.Results The limits of quantification of histamine and tyramine were both 10 mg/kg， which met the minimum limit requirement of 50 mg/kg specified in the current domestic and foreign standards for histamine. The recovery rate was about 90% and the relative standard deviation was about 10%. The results met the relevant requirements of food physical and chemical analysis.Conclusion The detection method is fast， efficient， stable， reliable and cost saving. It is suitable for the rapid detection of histamine and tyramine in milk.

Abstract:Objective To infer the relationship between bisphenol A （BPA） exposure and adverse health effects in humans， the human epidemiological data of BPA was evaluated by the weight of evidence approach.Methods Based on the weight of evidence approach， the human epidemiological research articles on BPA published between 2013 and 2020 were systematically searched， screened and classified. The selected articles were evaluated following the guidelines of evaluating the relevance and reliability of toxicological data developed by the China National Center for Food Safety Risk Assessment. The hazard assessment was performed based on different endpoints.Results A total of 188 papers were obtained screening from 134 897 records， of which 68 papers were evaluated as “A/B” or “B” in terms of relevance， and the rest were evaluated as “C”. Only the studies with the relevance evaluation grade of “A/B” or “B” were evaluated for reliability， of which 6 studies were evaluated as “high” reliability and 62 studies were evaluated as “medium” reliability. The endpoints of toxicological effects should include metabolic， reproductive and developmental， neurological， immunological and cardiovascular effects. However， the effect indicators across studies lacked consistency due to study population， exposure duration and indicator design.Conclusion Based on the available evidence of human epidemiological data， the relationship between BPA exposure and adverse health effects in humans is not yet clear.

Abstract:Objective To support the probabilistic assessment of food contact materials with consumption parameters and methodology， the establishment of consumption data based on food contact area with different types of alcoholic beverages and different food contact materials was studied.Methods Based on probability distribution， food contact surface area/volume ratio （S/V） data and alcoholic beverages consumption data were regarded as two independent distribution populations. Monte Carlo simulation was used to calculate the distribution of the food contact area based on consumption data. One thousand rounds of random sampling were conducted in the two populations to quantify the uncertainty.Results Categorized by alcoholic beverages-food contact material， beer-glass had the highest average food contact area based on consumption， with an average of 5.500 dm²/d and a 95%CI of 5.302-5.705 dm²/d. Categorized by food contact material， alcoholic beverages with aluminum coating had the highest average food contact area based on consumption， with an average of 5.213 dm²/d and a 95%CI of 4.929-5.532 dm²/d.Conclusion The food contact area based on consumption data of alcoholic beverages can be the basic parameter for the probabilistic assessment of food contact materials of alcoholic beverages in China， which can be used for the accurate dietary exposure assessment.

Abstract:Objective Through the 6^th Chinese Total Diet Study （TDS）， the contents of marker polychlorinated biphenyls （mPCBs） in representative Chinese dietary samples were obtained， and the dietary exposure assessment and temporal trend analysis of mPCBs were carried out.Methods Istope dilution dilution-high resolution gas chromatography-high resolution mass spectrometry （HRGC-HRMS） was used to determine mPCBs in food composite samples， and the intakes of mPCBs of Chinese residents represented by the standard man were evaluated by deterministic approach.Results The mPCBs were detected in all composite samples. The contents of mPCBs in varied dietary samples were different， and the animal diet were significantly higher than that of plant diet with the lowest in cereals and the highest in aquatic foods. The dietary intake of mPCBs of Chinese residents was 0.25［0.11， 0.62］ ng/kg?BW?d （geometric mean ± geometric mean standard deviation）. Compared with the results of the 4^th TDS and 5^th TDS， the dietary exposure level of Chinese residents decreased significantly （P<0.05）.Conclusion Although mPCBs were detected in all composite samples from 6^th TDS， the dietary exposure level of Chinese residents continued to decline compared with 4^th and 5^th TDS. Compared with the relevant research results from European and American countries， the dietary exposure level of Chinese residents is relatively low.

Abstract:Objective To understand the contamination of Staphylococcus aureus in raw chicken sold in Ji’nan and the carrying of enterotoxin genes in isolated strains， and assess the health risks of raw chicken products to consumers.Methods From March 2021 to November 2021， samples were collected from e-commerce platforms and circulation links such as large supermarkets， farmers’ markets， and meat retail stores in the main densely populated areas of Ji’nan city. The samples were tested according to GB 4789.10—2016 “Food Microbiology Testing Staphylococcus Aureus Test” to identify and detect 5 enterotoxin genes （sea， seb， sec， sed， see） of isolates through polymerase chain reaction （PCR）. The risk assessment software of risk ranger was used to assess the impact of Staphylococcus aureus in raw chicken sold in Ji’nan on consumer health.Results Among the 180 samples collected， a total of 55 samples detected Staphylococcus aureus， including 16 frozen chicken products from large supermarkets and e-commerce platforms （16/61）， 30 frozen chicken products from farmers’ markets and meat retail stores （30/60）， and 9 fresh whole chickens （9/55）. A total of 9 of the 55 isolates carried at least one classical enterotoxin gene. The semi-quantitative risk assessment results suggested that the risk level of Staphylococcus aureus caused by food poisoning in raw chicken sold in Ji’nan was high risk level， of which the risk value of frozen chicken products from farmers’ markets and meat product retail stores was 53， the risk value of fresh whole chicken was 52， and the risk value of frozen chicken products from large supermarkets and e-commerce platforms was 49.Conclusion The pollution level of Staphylococcus aureus in raw chicken sold in Ji’nan is relatively serious. Based on the risk assessment results， it is recommended that relevant departments strengthen supervision， standardize the transportation and storage conditions of frozen meat products on the market， reduce the risk of bacterial contamination of frozen chicken products， and protect the health of consumers.

Abstract:Objective To construct disease models of dietary inorganic arsenic-induced cancer and cardiovascular disease in China.Methods The different health hazard endpoints due to dietary inorganic arsenic should be identified. Based on the epidemiological data of related diseases in the Chinese population， the risk assessment method and counterfactual analysis method were used to calculate the attributable morbidity and mortality of cancer and cardiovascular disease caused by dietary inorganic arsenic exposure. Combined with disability weight and disease course characteristics， a disease model of cancer and cardiovascular disease caused by dietary inorganic arsenic exposure was established.Results Lifetime persistent dietary exposure to 1.41 μg/（kg?d） of inorganic arsenic in the population resulted in 0.135%， 0.010% and 0.034% of skin， bladder， and lung cancer incidence with 0.015%， 0.004% and 0.138% of mortality， respectively. The incidence and mortality of cardiovascular diseases caused by 1 μg/（kg?d） of dietary inorganic arsenic exposure were 0.082% and 0.025%， respectively.Conclusion The disease model can be used to calculate the burden of disease caused by food contaminants and quantify the health hazards caused by food contaminants.

Abstract:Objective To investigate the contamination status and dietary exposure risk of 3 perfluorinated substances and 2 chlorine substituted perfluoroalkyl ether sulfonate acids in fresh vegetables planted in the vicinity of typical fluorine chemical industry parks located in Guangdong province.Methods Ninety six vegetables were collected from the vicinity of 3 typical fluorine chemical industry parks and local markets in 2019. The concentrations of 3 perfluorinated substances ［perfluorooctane sulfonate acid （PFOS）， perfluorooctanoic acid （PFOA）， perfluorohexanesulfonic acid （PFHxS）］ and 2 chlorine substituted perfluoroalkyl ether sulfonate acids （6：2 Cl-PFESA and 8：2 Cl-PFESA） in fresh vegetables were detected using isotope dilution method by UPLC-QqQ-MS， and the point estimate was employed to estimate the levels of dietary exposure from fresh vegetables.Results PFOS and PFOA were detected in all samples， while chlorine substituted perfluoroalkyl ether sulfonates were detected in 2 leafy vegetable samples. The sum of average concentration of PFASs and Cl-PFESAs in vegetable samples was 0.792 ng/g fw （fresh weight， fw）， and it was two-fold higher compared the samples around the fluorine chemical industrial with the samples from local markets. The average concentration of 5 chemicals （1.11 ng/g fw） was the highest in leafy vegetables. The results of dietary exposure assessment indicated that the exposure levels of 3 perfluorinated compounds by consumption of fresh vegetables which planted surrounding fluorine chemical industry parks were 0.185-2.35 ng/kg·BW. The hazard indexes （HI） of PFOS and PFOA were greater than 1. The exposure level of chlorine substituted perfluoroalkyl ether sulfonate acids were lower.Conclusion The exposures of PFOS and PFOA of local general population exceeded the established thresholds for the adult residents. The risks of 2 chlorine substituted perfluoroalkyl ether sulfonate acids exposure from vegetables were low， which still need to be concerned.

Abstract:Objective To investigate the contamination and drug-resistant distribution of Salmonella in poultry meat in Shanghai and conduct a quantitative risk assessment.Methods According to the method of microbiological risk assessment， the risk assessment of Salmonella in poultry meat was carried out by four steps： hazard identification， hazard characterization， exposure assessment and risk characterization. The data for hazard identification and hazard characterization were derived from published scientific literatures and reports. Combining quantitative data of Salmonella with residents’ consumption data of poultry meat， a Beta-Poisson dose-response model and Monte Carlo simulation method were applied to analyze the health risk.Results The contamination rate of Salmonella in poultry meat was 13.0% （68/522） in Shanghai and about 78.2% （43/55） of the isolates showed antimicrobial resistance. The resistance rate to ampicillin， tetracycline and ampicillin/sulbactam was over 30%. The multiple drug resistance rate was 43.6% （24/55）. Estimated probability of infectious illness was 8.32×10^-5. That indicated the number of illnesses might reach 25 339 cases every year， of which 19 815 were infected by drug-resistant strains and 11 048 were infected by multi-drug-resistant strains. Sensitivity analysis showed that the initial contamination concentration， consumption per serving and two cross-contamination parameters had greater impact.Conclusion A high level antimicrobial resistance was found among Salmonella isolates from poultry meat in Shanghai， so was the multi-drug resistance condition. The risk of Salmonella in poultry meat is relatively high for Shanghai population， and cross-contamination is one of the main factors.

Abstract:Objective To provide reference for rational rice consumption and government safety supervision in China， the potential health risk in different populations was evaluated based on the investigation results of Cadmium （Cd） exposure from rice.Methods Cd of 6 249 rice samples was determined by inductively coupled plasma mass spectrometry （ICP-MS）， the Cd pollution level and distribution characteristic in rice were analyzed. Monte-Carlo simulations were employed to estimate the cumulative distribution function of Hazard quotients （HQ） and Cancer-risk index （CR） of Cd exposure from rice to assess the potential health risks of rice consumption.Results The average Cd content in rice samples from four regions， weighted by regional yield， was 0.1661 mg/kg， 25.99% of the overall rice samples and 56.64% of the rice samples from Central China exceeded the national limit. Analysis showed that Cd exposure level from rice in Northeast China was low and there was no carcinogenic or non-carcinogenic health risk. In other regions， the probability range of non-carcinogenic health risk level of HQ>1 was 0.06%~7.12% for adults and 0.15%~11.44% for children， respectively. The probability range of carcinogenic risk level of CR>10^-4 was 0.16%~72.55% for adults and 0.26%~77.93% for children， respectively. The potential health risk caused by Cd exposure from rice was highest in Central China.Conclusion There are high health risks of Cd exposure from rice in part of China， especially in Central China. The exposure risk of Cd from rice to children was higher than that of adults. It’s suggested that more attention should be paid to Cd exposure from rice for the critical areas and children.

Abstract:According to the requirements of the “Food Safety Law”， China has implemented the standard follow-up evaluation， and continuously improved the working machanism. Through this system， the regulators can collect comments on current effective standards， understand the implementation of the standards， find out the problems and analyze the reasons. It plays a key role in continuously improving the standards， and ensuring the scientificity， rationality and practicality of the standards. This paper reviews the development process of follow-up evaluation on national food safety standards in China since the establishment of National Food Safety Risk Assessment Center 10 years ago， and analyzes the advantages and disadvantages. It can provide reference for the next step to better implement the requirements of "the most stringent standard" and optimize the follow-up evaluation on national food safety standards in China.

Abstract:This paper takes the establishment of the national food safety standard system for food contact materials （FCM） as the mainline， combined with the role of FCM risk monitoring， risk assessment and related basic research， to demonstrate the achievements of China National Center for Food Safety Risk Assessment in the safety management of FCM in the past ten years since its establishment. The current shortcomings for the safety management of FCM are analyzed， and the follow-up work directions are proposed.

Abstract:Objective To provide basis for effective prevention and control of foodborne disease outbreaks caused by cross contamination of raw and cooked food in China’s Mainland， the reletive epidemiological characteristics was studied from 2010 to 2020.Methods The outbreaks of foodborne diseases caused by cross-contamination of raw and cooked food in the food processing link reported by the national foodborne disease outbreak monitoring system from 2010 to 2020 was collected， and a descriptive analysis of its epidemiological characteristics was conducted.Results From 2010 to 2020， the national foodborne disease outbreak monitoring system reported 667 （1.85%） foodborne disease outbreaks caused by cross-contamination of raw and cooked foods， including 11 766 cases of illness and 4 deaths. The high incidence seasons were the second and third quarters. The high incidence area was the southern area. The occurrence places were mainly catering service places （66.4%， 443/667） and collective canteens （22.6%， 151/667）. Causal food （excluding unknown food， multiple food and mixed food） mainly included meat （26.2%，175/667） and aquatic food （14.1%， 94/667）. Pathogenic microorganisms and toxins were the main pathogenic factors. The top three were Vibrio parahaemolyticus， Salmonella， Staphylococcus aureus and their enterotoxins. The high risk foods for Vibrio parahaemolyticus were aquatic products （55.1%， 75/136） and meat （37.5%， 51/136）. The high risk food for Salmonella was meat （62.2%， 46/74）. There were regional differences in major pathogenic factors， among which Vibrio parahaemolyticus （χ²=26.3， P<0.001） and Salmonella （χ²=18.3， P<0.001） contamination were different in eastern， southern and southwestern China.Conclusion Cross-contamination of raw and cooked is an important food safety problem that can not be ignored. In high temperature seasons and southern regions， especially in catering services and collective canteens， it is necessary to strengthen the health management of animal food preparation， the operation specifications of food practitioners， and the cognitive training of microbial foodborne diseases.

Abstract:Objective To describe the epidemiology of foodborne disease outbreaks in schools in China’s Mainland and to identify where preventive measures could be targeted.Methods Data on foodborne disease outbreaks in schools reported between 2010 and 2020 were extracted from Chinese National Foodborne Disease Outbreak Surveillance Network and analyzed.Results From 2010 to 2020， 2 101 outbreaks of foodborne disease in schools were reported in China’s Mainland and involved 44 510 cases， 15 193 hospitalizations and 6 deaths. The median number of cases per event was 21. The etiology of 50.9% （1 069/2 101） of the outbreaks was not determined， and suspected food of 21.2% （446/2 101） of the outbreaks was not determined. Microbial pathogens were the most common cause of the outbreaks with a known etiology （65.7%， 678/1 032） and 83.3% （5/6） of the deaths were chemical agents-related outbreaks. Staphylococcus aureus and its enterotoxins and Bacillus cereus were the most commonly identified pathogens， accounting for 14% （145/1 032） and 13% （135/1 032） of outbreak reports with a known etiology. The most common foods were meat products （9.2%， 194/2 101）， accidental ingestion of poisonous plants （8.8%， 184/2 101） and rice products （8.1%， 171/2 101）. September was a high month for foodborne disease outbreaks （20.2%， 425/2 101）. The main reasons for food contamination in outbreaks were insufficient heating or cooking time during food preparation， or accidental ingestion and misuse of poisonous plants and chemicals， and improper food storage.Conclusion Schools and relevant departments of food safety management should strengthen food safety guidance， supervision and management， regularly train canteen employees， carry out food safety education for primary and secondary school students， and strengthen cooperation among various departments and field hygiene investigations.

Abstract:Objective To understand the distribution characteristics of trigger factors of foodborne disease outbreaks caused by Staphylococcus aureus and its enterotoxin in China.Methods The data from the national foodborne disease outbreak monitoring system and literature from 2010 to 2020 were collected and sorted out， and the data of Staphylococcus aureus and its enterotoxin was analyzed.Results A total of 703 outbreaks from 2010 to 2020 were included （694 in the monitoring system and 9 in the literature）. Single latitude attribution analysis found that meat accounted for 28.3% （199/703） of the causal foods， improper storage accounted for 15.2% （107/703） during the whole process， and catering service places accounted for 85.2% （599/703） of the occouring places. The results of multi-dimensional analysis showed that the number of events in each season was the largest in Eastern China. In addition to meat， pastry food and rice flour food were the main cause in eastern and southern China， which were mostly caused by improper storage. Among the outbreaks that occurred in catering service places， meat and flour rice food were mainly caused by improper processing， while pastry food was mainly caused by improper storage.Conclusion The incidence of foodborne diseases caused by Staphylococcus aureus and its enterotoxin is high in meat products. It is necessary to strengthen the supervision of catering service places， food processing， storage and other sectors to reduce the risk of morbidity.

Abstract:Objective To study the research and application of foodborne disease risk prevention.Methods Taking the knowledge graph as the carrier， through knowledge extraction and relationship mining on the technical guide for epidemiological investigation of food safety accidents and internet data， the association between the pathogenic factors of common foodborne diseases and clinical manifestations， incubation period， susceptible population and food sources was deeply explored and obtained.Results The knowledge graph of foodborne diseases was constructed， including 390 nodes and 1 375 edges. On this basis， a knowledge question answering system was constructed to realize the automatic acquisition of answers to the clinical manifestations， susceptible populations， possible food sources and biological sample collection requirements of designated foodborne disease pathogenic factors.Conclusion This research innovatively proposed the design of foodborne disease risk prevention system based on knowledge graph technology. Meanwhile， the constructed foodborne disease knowledge graph can effectively solve unclear definition of key information and serious data islands in the related detection of pathogenic factors. The question answering system built on this basis was of great practical importance to improve the public’s knowledge of foodborne disease risks and to correct the food safety knowledge and operational behaviors of health care professionals related to foodborne diseases.

Abstract:Objective To provide the bases to build up the prevention and control measures， the epidemiology and changes of foodborne disease caused by plant and animal toxicants in China’s Mainland was studied.Methods The data reported from 2010 to 2020 was collected. The times， places， etiologic agents and causing factors were analyzed.Results A total of 5 244 outbreaks， which resulted in 37 610 illnesses and 271 deaths， were reported in this period. 35.37% （1 855/5 244） of the total outbreaks occurred in the second quarter and resulted in 31.18% （11 727/37 610） illnesses. Plant toxicants were reported for 4 794 outbreaks， resulting in 34 482 related illnesses and 222 deaths. Animal toxicants were reported for 450 outbreaks， resulting in 3 128 related illnesses and 49 deaths. Undercooked phaseolus were the most common cause of outbreaks （37.49%， 1 966/5 244）， followed by aconitine （8.28%， 434/5 244） and tung oil or seed （6.24%， 327/5 244）. Household and canteen were the most common locations of outbreaks. Mistaking and undercooked were the main causes.Conclusion Foodborne disease caused by plant and animal toxicants occurred in all seasons， and the second quarter is the peak. Undercooked phaseolus and improper prepared aconite were the main cause of poisoning. In view of the above epidemic characteristics， we should focus on the targeted publicity and education for families， so as to reduce the occurrence of the outbreaks.

Abstract:Objective To provide scientific basis for preventing foodborne outbreaks and carrying out targeted prevention and control measures， the seasonal characteristics of foodborne diarrheagenic Escherichia coli outbreaks in China’s Mainland from 2010 to 2020 was analyzed.Methods Circular distribution method was used to analyze the data about diarrheagenic Escherichia coli outbreaks which was collected by Foodborne Disease Outbreaks Surveillance System from 2010 to 2020.Results From 2010 to 2020， a total of 349 foodborne diarrheagenic Escherichia coli outbreaks were reported in China’s Mainland. Generally， the peak of Escherichia coli outbreaks was from May to September （74.50%， 260/349）， and there was a significant centralized trend in event distribution， with the peak day on July 10. The epidemic peak period was from April 24 to September 25.Conclusion There is an obvious seasonal trend in foodborne diarrheagenic Escherichia coli outbreaks in China’s Mainland， and the peak period is in summer and autumn. Effective prevention and control measures should be taken in time before the peak period.

Abstract:Objective To provide scientific evidence for the prevention and control of listeriosis， the incidence of listeriosis in Beijing from 2017 to 2019 was estimated.Methods Based on the sentinel listeriosis surveillance in Beijing from 2017 to 2019， the number of hospital admissions and listeriosis cases reported from 10 secondary or above comprehensive hospitals and 7 maternity hospitals in 8 districts were collected in from 2017 to 2019. The incidence rate of listeriosis in Beijing among the whole population and pregnant women were estimated by Bayesian method.Results The incidence rate of listeriosis in Beijing from 2017 to 2019 among the whole population estimated by Bayesian method was 0.25/100 000 （95% CI： 0.17-0.33）， with 53 （95% CI： 38-71） cases annually. The incidence rate among pregnant women was 12.89/100 000（95% CI： 9.03-17.39）， which was about 52 times of the whole population. The annual number of pregnancy-associated cases was 31 （95% CI： 20-43） ， accounting for 58% of the cases among whole population.Conclusion From 2017 to 2019， the incidence rate of listeriosis among the whole population in Beijing was close to other countries， indicating that more attention should be paid to the health education and disease surveillance. Listeriosis among pregnancy in Beijing had a higher incidence than the world average， suggesting that further analysis of the causes should be carried out and comprehensive intervention strategies targeted to pregnant populations are urgently needed.

Abstract:Objective To explore the effective prevention of wild mushroom poisoning， the years of life lost （YLLs） from wild mushroom poisoning in Yunnan Province from 2017 to 2021 was calculated .Methods The death data of wild mushroom poisoning in Yunnan Province were collated according to gender， age and year. The YLLs was calculated based on the World Health Organization excel calculation template， and the YLLs was compared among different age， gender and year groups. The indirect economic loss was estimated using human capital approach.Results The YLLs due to wild mushroom poisoning was 2 760 person-years （5.70 person years per 100 000 population）. People aged from 30 to 59 years old were a risk group for wild mushroom poisoning with YLLs of 1 602 person-years. Children aged <5 years old were also at high risk for wild mushroom poisoning （9.10 person-years/100 000 population）. The intensity of YLLs and YLLs in male was higher than that in female. The total indirect economic burden of 139 deaths from wild mushroom poisoning in Yunnan province was 70.794 2 million yuan， 509 300 yuan per capita.Conclusion The wild mushroom poisoning is one of the important causes of foodborne diseases death in Yunnan province. It is necessary to strengthen education and supervision of food safety， and improve the ability of medical treatment and epidemiological investigation of wild mushroom poisoning at the primary health care facility.

Abstract:Objective To conduct the pathogenic bacteria detection， the carriage of virulence genes and the source tracing analysis in a foodborne disease outbreak event.Methods The samples collected from the event were rapid screened by FilmArray multiplex polymerase chain reacion（PCR） system， and were conducted to bacteria culture， isolation and identification simultaneously. Real-time PCR was performed for virulence genes of isolated strains. Homologous analysis of the strains was studied using 16S rRNA gene sequence analysis and pulsed field gel electrophoresis（PFGE） molecular genotyping.Results Campylobacter jejuni strains were detected from anal swabs of 2 patients and 4 canteen workers. All of the 6 Campylobacter jejuni strains carried flaA， cadF， imaA， cdtA， cdtB and cdtC virulence genes. All the strains were closely associated with Campylobacter jejuni via 16S rRNA gene sequence analysis， but the phylogenetic distance between one strain and the other 5 strains was slightly further. The results of PFGE showed that 6 strains of Campylobacter jejuni could be divided into 3 PFGE patterns， 3 strains and other 2 strains belonged to the same PFGE pattern respectively， with similarity of 52.2%. The rest belonged to a different PFGE pattern， with similarity of 26.7% compared to others.Conclusion Laboratory analysis indicated that different clones of Campylobacter jejuni infection was the cause of this foodborne disease outbreak.

Abstract:Objective To provide scientific basis for improving the nutrition and health status of Chinese students， the status of main food intake and its influencing factors of primary school students in a poverty-alleviation county in central China were analyzed.Methods A total of 674 students from grade two to grade four were randomly selected from 2 primary schools in urban and rural areas of a poverty-alleviation county in central China. The frequency of major food intake， family and personal status of 674 students were collected by student questionnaire.Results Only 12.9% of the students in poverty-alleviation county ate meat more than once per day， 18.5% of the students consumed more than one egg per day， 8.2% of the students consumed 1 package or more of dairy products per day， 9.8% of the students consumed soy products once or more per day， 13.4% of the students ate more than 1 time of fruit per day， and 22.8% of the students ate more than 3 kinds of vegetables per day. The intake frequencies of eggs and fruits were significantly different among different education levels of their mothers（P<0.05）. The intake frequencies of dairy products， soy products， fruits and vegetables were significantly different between urban and rural areas （P<0.05）. The results of multivariate analysis showed that urban students were more likely to eat meat 4 or more times per week （OR=2.618， 95%CI： 1.364~5.027， P<0.05）， and students whose mothers had a high school education or above were more likely to eat eggs 4 or more times per week （OR=2.508， 95%CI： 1.314~4.784， P<0.05）.Conclusion The intake of meat， eggs and milk was insufficient for primary school students in a poverty-alleviation county in China， especially in rural areas， and the intake frequency were related to the education level of mothers. Measures should be taken to provide guidance on proper diet for primary school students and their mothers.

Abstract:Objective To investigate the influencing factors of hyperuricemia （HUA） among children and adolescents， and provide evidences for early intervention.Methods From 2016 to 2017， a multi-stage stratified random sampling method was used to select three urban and rural sites in Chongqing， and some students aged 7~17 years were selected to conduct questionnaires， physical measurements and laboratory tests. Factor analysis was used to analyze dietary patterns. Regression and classification tree models were used to explore the influencing factors of HUA.Results A total of 1 544 students were enrolled in the study. The prevalence rate of HUA was 19.49% which was higher among male and elder students. Four common dietary patterns including meat and vegetable/fruit， snacks， cereal/potato/bean/nut and staple were included in the factor analysis， and the contribution rate to total variance was 42.641%. Scores of each pattern were divided into four ranking （Q1~Q4） from low to high. The results of univariate regression showed that participants with the fourth quartile （Q4） score of meat and vegetable/ fruit pattern had a higher risk of HUA （OR=1.687） compared to those with the first quartile （Q1） score， while the odds ratio was 1.764 in staple pattern； participants with the Q4 score of bean/nut pattern had a lower risk of HUA （OR=0.588） compared to those with Q1 score. After adjusting for confounding factors of monitoring area， gender， age， waist circumference， BMI， blood lipids， blood sugar and physical activity， participants with Q4 score had a lower risk of HUA （OR=0.638）compared to those with Q1 score in cereal/potato and bean/nut pattern. Classification tree model showed that age， gender and BMI level were the main influencing factors of HUA among this group.Conclusion The prevalence of HUA in children and adolescents aged 7~17 years in Chongqing was high. Strong attention should be paid to the incidence of HUA among boys， especially aged 12 years and above， overweight and obese， and the dietary pattern of cereal/potato and bean/nut pattern should be encouraged.

Abstract:Objective To investigate the microbial contamination of liquid milk in some municipalities in Hubei Province in 2021.Methods A total of 101 raw milk， pasteurized milk and sterilized milk from production， wholesale and retail were collected. The total number of bacterial colonies， aerobic Bacillus and thermophilic aerobic Bacillus， alkaline phosphatase of the samples were detected.Results The overall exceeding rates of raw milk， pasteurized milk and sterilized milk （any one of the four indicators exceeded the standard） were 52.94%， 8.70% and 1.64%， respectively. The detection rates of aerobic Bacillus were 52.94%， 4.35% and 1.64%， respectively. The value of alkaline phosphatase in one retail whole fat pasteurized milk sample was 409 mU/L. The shelf days of pasteurized milk had no correlation with the value of alkaline phosphatase （r=0.10， P=0.65）. The detection rates of samples exceeding the standard in production and processing sector and circulation were 52.94% and 3.57%， respectively， with statistically significant differences （χ²=32.92， P<0.001）. There was no significant difference in the exceeding rate of samples between convenience stores/whole sale markets and shopping mall/supermarkets （P>0.05）.Conclusion The pollution of aerobic Bacillus in raw milk was common in Hubei Province. Pasteurized milk and sterilized milk had the problem of microbial contamination which violated the standard. It is recommended to further investigate the causes， analyze the sources of contamination， provide the basis for targeted measures， and strengthen the monitoring of the total number of aerobic Bacillus， alkaline phosphatase and other indicators in liquid milk， which can provid baseline data for establishing appropriate limit standards.

Abstract:Objective To provide the scientific basis for prevention of such incidents， a foodborne disease outbreak in school caused by Salmonella enteritidis was investigated and the risk factors was traced.Methods Descriptive epidemiological methods were used to analyze the characteristics of the incident. Case-control studies were used to investigate the suspected food. Environmental hygiene investigations were used to trace the process of food contamination， and pathogen isolation， serotyping analysis， and pulsed-field gel electrophoresis （PFGE） were used to detect and analyze the Salmonella enteritidis isolated from the patients， food and environmental samples.Results A total of 71 patients were reported in this outbreak， and the epidemic curves were consistent with a sustained homologous outbreak pattern. The case-control study， environmental health survey and etiology study suggested that sandwiches sold in the school supermarket were the etiological food for this incident （OR=302.09， 95%CI=75.18~1 213.97）. Salmonella isolates from 8 samples （12.70%， 8/63） collected from patients， food and environmental were detected， and their PFGE profile were identical， confirming that the salad dressing used in the cause-food sandwich was contaminated with Salmonella during the preparation process， which led to this foodborne illness outbreak.Conclusion This outbreak was caused by sandwiches contaminated by Salmonella enteritidis， and the sandwiches were contaminated by homemade salad dressing. It is suggested that all foods containing raw egg ingredients that have not been adequately heat-treated should be banned from schools， and that the relevant administrative departments should strengthen sanitary supervision of such foods.

Abstract:Objective To provide a basis for formulating applicable prevention and control strategies for toadstool poisoning， the epidemiological characteristics of toadstool poisoning events in Enshi Tujia & Miao Autonomous Prefecture（Enshi）， Hubei Province from 2015 to 2021 was analyzed.Methods The descriptive analysis was conducted on poisoning incidents reported by Hubei Food Safety Standards， Monitoring and Evaluation Platform.Results From 2015 to 2021， a total of 558 cases and 804 patients of toadstool poisoning were reported in Enshi. The main cause of toadstool poisoning was accidental taking and eating. There were 45 foodborne outbreaks caused by toadstool poisoning， with 152 cases and 7 deaths， and the fatality rate was 4.61%. From the second quarter to the fourth quarter， toadstool poisoning occurred frequently in rural households. The prevention and control strategies mainly included monitoring， publicity， risk analysis and assessment， timely treatment and other common measures.Conclusion According to the retrospective analysis results of poisoning poisoning events in Enshi from 2015 to 2021， it is needed to establish effective risk warning system and strengthen the publicity and education to prevent or reduce the occurrence of poisoning according to the key seasons， regions， places and population.

Abstract:Objective To investigate the microbial contamination of prepared beverage in China.Methods According to the principle of random sampling， 3 583 samples of prepared beverage and edible ice were collected from representative restaurants， beverage shops， fast food restaurants and collective school canteenagers in municipalities and autonomous regions of China. The total number of bacteria， coliform bacteria， Staphylococcus aureus and Salmonella were detected by the national standard method.Results Total colonies of 8.42% of the product were greater than 10⁵ CFU/mL， coliforms of 19.32% of the products were greater than 10² MPN/mL. The detection rates of S. aureus and Salmonella were 2.56% and 0.09%， respectively， which were lower than 10² MPN/mL. The contamination in protein drinks was the most serious， the ratios of total colonies over 10⁵ CFU/mL and coliforms over 10² MPN/mL were 21.35% and 32.97%， respectively. From March to May， the sanitary condition of prepared beverages was the worst， and the ratio of total number of colonies greater than 10⁵ CFU/mL was 14.80%. The highest detection rate of S. aureus was 5.24% in restaurants and hotels.Conclusion The food safety status of current prepared beverage is generally good， but related departments should also strengthen the supervision and inspection of the processing place.

Abstract:There are many kinds of chemical hazards in food， and their contents are generally at trace and ultra trace levels. Because the food matrix is complex， it is very important to select appropriate sample preparation techniques to obtain reliable detection results at low concentration level. According to the detection needs of different types of compounds and the characteristics and analysis purposes of different food matrices， this paper discusses the selection of sample preparation technique based on the experience in the development of sample preparation methods for food chemical hazards in the recent 10 years. A practical sample preparation method selection strategy based on "food matrix" and "target analyte" is proposed. And the progress of cutting-edge technique is reviewed. In addition， on the basis of application examples， suggestions on the development of sample preparation methods are put forward to provide references for grassroots technicians to select reliable sample preparation methods.

Abstract:As widely used synthetic chemicals， perfluorooctane sulfonic acid （PFOS） and perfluorooctanic acid （PFOA） are ubiquitous in the environment and the human body. Due to the extensive toxic effects and bioaccumulation of PFOS/PFOA，their impact on human health has attracted more and more attention. The absorption， distribution， metabolism， excretion and toxic effects of PFOS/PFOA in mammals are systematically summarized in this paper. Moreover，the safety limits of PFOS/PFOA are summarizes herein as well as the internal exposure levels of PFOS/PFOA in Chinese general population based on published literature in order to provide a scientific basis for PFOS/PFOA risk assessment and risk management.