Abstract:Total diet study (TDS) is designed to collect concentration data of chemicals in foods analysed as consumed by the population living in a country and, if possible and where relevant, population subgroups. The WHO strongly recommends the member countries to carry out TDS and the TDS data are used to assess the chronic dietary exposure as the most economic, reliable and effective tool. China has put TDS as groundwork for the risk assessment and standard setup action plan. The comment briefly introduces the TDS background, evolution from start, development and maturity in the past 30 years. And also, it comments TDS in the position of exposure science in food safety.

Abstract:Food safety is not only the most concerned topic for consumers, but also an important basis for the development of the country. With the rapid development of China's food industry, all kinds of new type, take-away and other convenient foods are closely connected with people's lives. Lots of food safety related problems, such as additives, pesticides and veterinary drug residues, food packaging material and inspection, food production, normative operation, expired food recycling, emerge endlessly. Although traditional food safety management system cannot effectively resolve the current complex food safety issues, there still much room to improve, hazard analysis and critical control point (HACCP) system can empower production enterprises to identify potential hazards and regulate them at an early stage, so as to avoid harm and loss in consumer's health and social welfare. HACCP system could ensure the quality and safety of food products, which is welcomed and applicated in international food industry. However, the relevant food safety and registration laws do not make mandatory provisions on the application of HACCP system in small and medium-sized food enterprises. Most enterprises don't apply HACCP system actively because of theenterprise cost, talent training and management issues. This paper summarizes the development and application of HACCP in food enterprises in China, hoping it could promote the application of HACCP in food enterprises, and reduce the probability of food safety problems.

Abstract:The Chinese Journal of Food Hygiene was founded in 1989 by DAI Yin, former director of Institute of Food Hygiene Supervision and Inspection, the Ministry of Health. It is currently under the supervision of the National Health Commission. Chinese Journal of Food Hygiene is an academic journal jointly sponsored by the Chinese Preventive Medicine Association and the Chinese Medical Information and big data Association. With the dedication of four editors-in-chief (DAI Yin, LI Xiaofang, HE Laiying and WU Yongning), the chairman of the editorial board (CHEN Chunming, WANG Maoqi, YAN Weixing and LU Jiang) and the editors, the Chinese Journal of Food Hygiene has become an authoritative academic journal in the field of food hygiene in China. It is a Chinese core journal, a science and technology core journal of China, an outstanding science and technology journal of China, and a core database journal of China Science Citation Database. Its impact factor ranks in the top six in the field of preventive medicine for many years. It has been rated as the excellent journal of Chinese Preventive Medicine Association for many times. Since the journal was founded, more than 5 100 papers have been published. The journal has played a positive role in exchanging work experience, displaying scientific research results, publishing progress at home and abroad, promoting mutual cooperation and achieving the goal of healthy China.

Abstract:Objective To study the short-term oral toxicity and the effect of zinc oxide nanoparticles on intestinal immune in rats. Methods Weaning rats were randomly divided into 4 groups:control group, low, medium and high-dose groups (10 male and famale rats in each group). Zinc oxide nanoparticles were intragastrically administered at doses of 87.5,5 and 350 mg/kg BW for 28 days, respectively. Blood samples were collected on day 29 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. Flow cytometric analysis of lymphocyte subsets of Peyer's patch and the level of secretory immunoglobulin A (SIgA) in intestinal fluid were detected. Results There were no toxicologically significant changes in clinical signs, body weight, food consumption, necropsy findings and organ weights, hematological and clinical biochemical values. Histopathological examination showed an increased incidence of focal epithelial cell exfoliation in gastric mucosa, inflammatory cell infiltration and edema in gastric submucosa, and villous epithelial cell exfoliation in small intestine. Compared with the control group, the number of lesions in the high dose group increased significantly. Lymphocytes phenotyping analysis showed a significant increase in percentage of T lymphocytes and decrease in percentage of natural killer(NK)cell in Peyer's patch. The concentration of SIgA had no significant difference between dose groups(P＞0.05). Conclusion The ingestion of zinc oxide nanoparticles can cause gastrointestinal mucosal damage and can affect the intestinal immune index in rats, at 350 mg/kg BW dose.

Abstract:Objective Prevalence of Salmonella in retail raw chicken cuts were collected from Yangling and its surrounding districts, characterizations including antibiotic susceptibility, serotype and genotype based on pulse field gel electrophoresis (PFGE) of Salmonella isolates in these samples were investigated to support basic data for foodborne Salmonella outbreaks prediction. Methods Salmonella was isolated and identified according to procedures of the National Food Safety Standard of Food Microbiological Examination:Salmonella (GB 4789.4-2010), the serotype was determined via serum agglutination method, the genotype was determined via protocol of PFGE, and DNA profiles were clustered by BioNumerics software. Results Thirty-four (18.1%) of 188 retail raw chicken cut samples were positive for Salmonella, the detection rate of Salmonella in farmer's market (24.6%,29/118) was higher than that in supermarket (7.1%,5/70); the detection rates of Salmonella in chicken leg, chicken feet, chicken neck, chicken liver were higher than those in chicken intestine and gizzard. Ten serotypes were identified from 34 Salmonella isolates, and the most commonly detected serotype was S.Corvallis, which was significantly (P<0.05) more prevalent than other serotypes including S.Typhimurium, S.Derby, and so on. All isolates resisted to sulfamethoxazole, chloramphenicol, ceftiofur and ciprofloxacin; the rates of isolates resisted to trimethoprim-sulfamethoxazole, nalidixic acid, tetracycline, streptomycin, ampicillin, and amoxicillin-clavulanic were above 50%. PFGE profiles of 34 Salmonella isolates could be grouped into 11 clusters, the isolates with the same serotype were commonly grouped into the same cluster. PFGE profiles of isolates with the same serotype and recovered from different samples in same sampling time and marketplace were similar or highly similar, which indicated the retail chickens might be cross-contaminated by Salmonella during processing and/or sale. Genotype of Salmonella isolates from farmer's market was more diversed than those from supermarkets. Conclusion The retail raw chicken cuts in Yangling and its surrounding districts were contaminated by Salmonella, which not only exhibited diverse serotypes and genotypes, but high frequency of antibiotic resistance.

Abstract:Objective The virulence genes and the antibiotic resistance of Bacillus cereus isolates from commercially available foods in Chengdu from 2014 to 2016 were investigated in this study. Methods From 2014 to 2016,0 food samples were collected from farmers' market in Chengdu and roadside food stalls. Suspected strains were isolated according to the GB 4789.14-2014. The house-keeping genes detection and 16S rDNA were sequenced to further identify B.cereus isolates. The specific virulence genes and resistance to antibiotics of B.cereus were also detected. Results From 2014 to 2016, the total isolation rate of B.cereus was 17.6% (58/330); the B.cereus detection rates in different food types was significantly different (χ²=29.683,P<0.01). The B.cereus isolation rates in different years was not significantly different (χ²=5.835,P>0.05). Rice noodles, ready-to-eat salads and marinated products were the main contaminated foods for B.cereus. From 2014 to 2016, the detection rates of diarrhea-type toxin genes (hbl, nhe, bceT, cytK, entFM) were much higher than that of vomiting toxin genes (ces and cer). The resistance rates of the isolated strains to tetracycline (TCY), erythromycin (ERY) and clindamycin (CLI) were 29.3% (17/58), 24.1% (14/58) and 22.4% (13/58), respectively. Conclusion The result of this study indicated that the virulence genes of B.cereus isolated from the commercially available foods in Chengdu were diverse, and the resistance rate of B.cereus to TCY, ERY and CLI was relatively high, which posed a potential threat to food safety.

Abstract:Objective To establish a method for the simultaneous determination of fipronil and its metabolites in eggs by QuEChERS-gas chromatography-tandem mass spectrometry. Methods 3 ml water was added into egg samples (5.0 g), extracted with 10 ml acetonitrile, and purified in an EMR-Lipids tube. The analytes were performed on DB-5MS column (30 m×0.25 mm, 0.25 μm), detected under multiple reaction monitoring (MRM) mode, and was quantified by external standard method with matrix matching curve. Results The fipronil and its metabolites had a good linear in the range of 0-60 μg/L with the correlation coefficient r≥0.999 0. The detection limits (S/N=3) were 0.5-0.8 μg/kg, and the limits of quantification (S/N=10) were 1.7-2.7 μg/kg. The recoveries were 92.0%-115.5%, and the relative standard deviation (RSD) were 3.6%-6.8% (n=6). Conclusion The method has the characteristics of simple pretreatment, high sensitivity and high recoveries, and it is suitable for the accurate determination of fipronil and its metabolites in eggs.

Abstract:Objective To study the pulsed field gel electrophoresis(PFGE)type and antimicrobial resistance of Salmonella Typhimurium (S. Typhimurium) isolated from duck and swine, so as to provide support for source-tracking of S.Typhimurium strains in Sichuan Province. Methods A Total of 47 S. Typhimurium strains isolated from pigs and ducks were analyzed by PFGE and tested for antimicrobial resistance for 9 antibiotics by minimal inhibitory concentration (MIC) method. Results S. Typhimurium strains isolated from pigs and ducks differed in PFGE type and antimicrobial resistance. The strains isolated from ducks were clustered in cluster I and the pig source strains clustered in cluster II. The resistance rate of strains from pigs to the 6 kinds of antibiotics including ampicillin, ciprofloxacin, chloramphenicol, gentamycin, tetracycline and sulfamethoxazole compound trimethoprim were significantly higher than that of strains from ducks. S.Typhimurium with different PFGE types were different in the isolation areas and antimicrobial resistance. SCSTm-10 strains were located in MY region, and SCSTm-11 were mainly isolated in ZY region. The resistant rates of SCSTm-10 on sulfamethoxazole/trimethoprim and ciprofloxacin were higher than SCSTm-11. Conclusion PFGE typing could obtain the clustering information of isolated source, isolation location and antimicrobial resistance of S.Typhimurium in Sichuan Province, and provide support for the epidemiological investigation of S. Typhimurium infections.

Abstract:Objective To investigate the pathogenic types and distribution of diarrheogenic Escherichia coli (DEC) from foodborne diseases in Henan Province, and provide reference data for the prevention and control of foodborne diseases. Methods Fecal specimens from patients with foodborne diseases in sentinel hospitals were examined for DEC to determine pathogenic and virulent genes. Results 215 of 4 137 stool specimens were positive, and the positive rate was 5.2%. Four of them were mixed DEC infection of different types. 219 strains of DEC were isolated, including 156 strains of enteroaggregative Escherichia coli (EAEC), 28 strains of enterotoxigenic Escherichia coli (ETEC), 28 strains of enteropathogenic Escherichia coli (EPEC), 2 strains of enterohemorrhagic Escherichia coli (EHEC), and 5 strains of enteroinvasive Escherichia coli (EIEC). 95 cases of patients were between 0 and 5 years old, with the proportion of 44.2%. DEC cases had a peak in June and October, but was found all year round. In terms of suspicious food exposure, 34 cases were caused by meat and meat products, 31 cases by milk and dairy products, accounting for 17.3% (34/196) and 15.8% (31/196) respectively. Conclusion The genotype of DEC in foodborne diseases in Henan was mainly EAEC. Infection was mainly in children under 5 years old. It occurs frequently in summer and autumn. Meat and meat products, milk and dairy products caused more cases.

Abstract:Objective To understand the status and characteristics of Salmonella contamination in food in Guangxi, and to provide scientific basis for reducing contamination and preventing and controlling foodborne diseases. Methods A total of 60 174 Salmonella samples were collected from 14 cities in Guangxi from 2012 to 2017. Salmonella was detected in accordance with the national standards (GB 4789.4-2010). Results The detection rates of Salmonella in fresh foods were 10.3%(399/3 883) for raw meat and products, 6.2%(50/806) for raw aquatic products, 0.5%(2/440) for frozen rice noodles and 0.0%(0/583) for fresh eggs, respectively. The detection rates of Salmonella in ready-to-eat food were 0.6%(58/10 175) for cooked meat products, 0.3%(39/14 721) for catering food, 1.0%(5/489) for raw vegetables and products, respectively. The detection rates of baked and fried foods, beverages, fruits and products were 0.1%, and that of cooked eggs, soybean products, frozen drinks, condiments were not detected. A total of 51 serotypes were detected in raw meat and raw meat products. Salmonella Derby was the dominant serotype (16.2%,70/432), mainly in raw pork. 32 serotypes were detected in ready-to-eat foods. Salmonella Derby was the dominant serotype (14.5%,11/76), mainly in cooked meat products. Conclusion The main source of Salmonella was livestock and poultry meat, while cold dishes were at high risk among ready-to-eat food. Prevention and control from farm to table should be strengthened to reduce the occurrence of foodborne diseases.

Abstract:Objective The epidemiological characteristics of foodborne diseases in Shanxi Province in 2017 were analyzed, and the spatial aggregation of foodborne diseases was explored in order to provide basis for scientific prevention and control measures. Methods The epidemiological characteristics of foodborne diseases in Shanxi Province were analyzed by geographic information system technology and descriptive epidemiological method, and the spatial aggregation of foodborne diseases was studied by spatial autocorrelation method. Results In 2017,7 727 cases of foodborne diseases were reported in Shanxi Province, with a reported incidence of 7.5/10 000.Male cases were more common than female cases, and the sex ratio was 1.02∶1. The 20-39 age group reported the most cases(27.6%,7 661/27 727). Farmers(40.6%,11 266/27 727) and younger students(13.2%,3 652/27 727) had more cases. The top three suspicious foods were:fruits and products(26.0%,7 207/27 719), cereals and products(17.9%,4 963/27 719), and meats and products(11.6%,3 207/27 719). Households were the most common eating places(73.2%,23 429/31 988). The overall distribution of the disease reported by the three-dimensional trend analysis was:gradually rising from north to south and decreasing from west to east, consistent with the result presented in the reported incidence map. The incidence of foodborne diseases reported a spatial positive correlation, and the high-high gathering areas were Fushan County, Xi County, Daning County, Yonghe County, Gu County and Ji County. Conclusion The incidence of foodborne diseases in Shanxi Province had obvious spatial aggregation.

Abstract:Objective To investigate Salmonella contamination in food in Wenzhou, and to analyze the serotype distribution, drug resistance, and pulsed-field gel electophroresis(PFGE)patterns. Methods According to GB 4789.4-2016, the Salmonella strains were isolated, identified and serotyped. The broth microdilution method was used for drug sensitivity test. All strains were subtyped by PFGE. Results Six categories of 2 039 food samples were collected. 37 Salmonella strains were isolated with a positive isolation rate of 1.8%. Raw poultry meat and raw livestock meat got the highest detection rates with 6.9%(20/290) and 3.4%(10/290), respectively. The 37 Salmonella isolates belonged to 16 serotypes,including S. Typhimurium, S. Derby and S. Enteritidis as the dominant serotypes. 81.1%(30/37) of the strains showed different resistance levels to 17 kinds of antibiotics, and displayed 24 kinds of multiple drug resistant spectrums. The multiple antibiotic resistance rate reached 56.8%(21/37). The 37 isolates were divided into 31 PFGE patterns which showed polymorphism. Conclusion Food was contaminated to some degree by Salmonella in Wenzhou, and the antibiotic resistance was severe. The aggregation of PFGE patterns was related to the serotype of Salmonella, but had no obvious relation to the resistant spectrum.

Abstract:Objective To investigate the status of microbial contamination in the production process of stewed meat products in a food factory in Nanjing. Methods Totally 396 samples of 120 food products (60 raw materials, 28 intermediate products, 24 finished products, and 8 final finished products), as well as 204 environmental samples, 58 aerosol samples and 14 water samples in the production process of stewed meat products were collected from a food factory in Nanjing from 2016 to 2017. Hygienic indicator bacteria and main foodborne pathogens were detected according to GB 4789 food microbiological test series standard and GB/T 16294-2010 Test Method for Setting Microbe Bacteria in Clean Room of the Pharmaceutical Industry and serological identification of Salmonella was determined. Results Twenty-four strains of Listeria were detected in food samples and environmental samples (7.4%,24/324), 5 strains of Staphylococcus aureus were detected (2.6%,5/196) and 6 strains of Salmonella were detected (1.9%,6/324). There were two strains belongs to Listeria monocytogenes, other Listeria species were mainly Listeria grayi and Listeria ivanovii. Four serotypes of Salmonella, were identified as 2 strains of Salmonella Enteritis, 2 strains of Salmonella Typhimurium, 1 strain of Salmonella Isangi and 1 strain of Salmonella Arizona. Pathogenic bacteria had been isolated in raw materials, intermediate products, environment, food processors, instruments and cleaning tools samples, but no pathogenic bacteria were detected in the finished products and final finished products. Conclusion There were certain kinds of pathogenic bacteria contamination in raw materials and environment samples during the process of sauced meat products.

Abstract:Objective To assess of the exposure risk and the potential health hazards of four heavy metals in aquatic products in Chinese residents. Methods Based on the concentration data of arsenic, cadmium, mercury and lead collected in 2013-2017 and the food consumption data in China, the dietary exposures of the four heavy metals were estimated by semi-probabilistic model. The health guidance value or bench mark dose (BMD) was adopted to assess the potential health risks of the heavy metals. Results The exposures of Cd and CH₃Hg in the general population were lower than the corresponding health guidance value,except for the average cadmium exposure in women over 66 years of age. The Cd and CH₃Hg average exposure was more than 5% of the corresponding health guidance value, and the high-end exposure (P95) was more than 20% of that. Meanwhile the margin of exposure (MOE) for Pb and iAs were higher than 1. The average consumer exposure and high exposure (P95) of the four heavy metals in 2-6 years old group were the highest among all age groups in the whole population except the exposure to iAs. Sea crab and fish were the main sources of the dietary exposure contribution of the four heavy metals in aquatic products. Conclusion The exposures to lead, cadmium, mercury and arsenic through aquatic products were at a relatively safe level, but it reached the level of management through the establishment of limit standards. Fish and sea crab were the main sources of the dietary exposure contribution of the four heavy metals in aquatic products.The heavy metal exposure of high-consuming population needs to be paid attention to. It was suggested that further studies on cumulative exposure assessment of heavy metals be carried out to clarify the cumulative exposure risk of heavy metals in aquatic products.

Abstract:Objective To analyze the contamination of 11 organophosphorus pesticides in fresh vegetables from Yunnan Province and to assess the cumulative risk after chronic exposure. Methods Eleven organophosphorus pesticides content in fresh vegetables in Yunnan Province from 2012 to 2017 were analyzed, combined with the fresh vegetables consumption of National Nutrition and Health Survey in 2012, and hazard index method was used to assess the cumulative risk of organophosphate pesticides in Yunnan Province. Results The total detection rate of 11 organophosphorus pesticides in 2 150 samples was 14.1%(303/2 150),the exceeding standard rate was 4.3%(93/2 150).The result showed that the average hazard index of residents in Yunnan Province was 0.382 5 by hazard index method, the average hazard index of urban male (0.526 7) and urban low-income (0.489 0) were relatively high, but both less than 1. The chronic cumulative exposure contribution rate of omethoate was the highest(48.3%). Conclusion There was organophosphorus pesticide pollution of fresh vegetables in Yunnan Province, the risk of chronic accumulated exposure was low. Strengthening supervision of pesticide production and application still could not be ignored in order to control illegal use and abuse.

Abstract:Objective Preliminary establish the administration and management protocol for plant material novel food standards. Methods The announcements for plant novel food (the original new resource food) approved in 2008-2017 by national health and family planning commission were analyzed. The Chinese name, Latin name, source of plant species, edible parts, cultivation method, range of application, consumption recommendation, unsuitable population and quality specification requirements were compared and analyzed. The current problems during the practice were summarize, and the solution was put forward. Results The current plant novel food announcement had some practical issues, such as the consistancy of format and description language, the intelligibility on the food safety indicators, the applicability, and etc. Conclusion This paper advises the government to improve the content of plant novel food announcement and put forward some suggestions on the standards procedures, methods and technical contents. To improve the technical indicators for the plant novel food material, standard review system is needed.

Abstract:Objective To analyze the current provincial food safety standards to make suggestions for the management. Methods Two hundred and forty-four provincial food safety standards released by provincial health administration departments were collected in this investigation. The classification, scope of the provincial food safety standards and the relationship with national food safety standards were analyzed. Results The main problems existing in the current provincial food safety standards include the unclear concept of “local characteristic food” and the inconsistency with the content and scope of the national food safety standards. Conclusion The management of provincial food safety standards should focus on clearing up the current provincial food safety standards, clarifying the concept of local characteristic food, and speeding up the construction of food safety standards system.

Abstract:Objective To investigate and analyze the epidemiological characteristics of suspected milk poisoning, identify the causes of food poisoning incident, and provide the reference for similar food poisoning emergencies. Methods According to the field epidemiological investigation, the samples were tested by high performance liquid chromatography, and the causes of food poisoning were determined by comprehensive analysis. Results Twenty eight people were poisoned, sodium dehydroacetate was detected in the milk samples tested, the content was 1.70 and 1.71 g/kg, and no other toxic substances were found. Conclusion The poisoning was caused by the illegal addition of high concentration sodium dehydroacetate in milk.

Abstract:Objective To investigate the wild mushroom species causing a food poisoning in Changxing County, Zhejiang Province, analyze the causes of the incident and summarize the experience of investigation,purposed to provide references for prevention and proper treatment. Methods The epidemiological investigation, morphological identification and phylogenetic identification were used to analyze the poisoning event. Results Epidemiological investigation found that three patients were poisoned due to mushrooms picked by themselves, among which 1 case was severe and 2 cases were mild, and the attack rate was 100%. The main clinical manifestations were nausea, vomiting and diarrhea. One patient developed severe rhabdomyolysis poisoning after a short pseudo-recovery period. The highest level of serum creatine kinase (CK) was 318 200 U/L. The mushroom samples were identified as Russula subnigricans by morphological identification and phylogenetic identification. Conclusion This incident was a case of mushroom poisoning caused by accidental ingestion of Russula subnigricans. The key to prevent poisonous mushroom poisoning is to carry out publicity and education, enhance people's awareness of prevention and improve the ability of medical institutions to diagnose and treat poisonous mushrooms.