Abstract:Nutritional toxicology is a new discipline formed by the cross-integration of science of nutrition and toxicology, which mainly investigates the following aspects:adverse effects of excessive nutrients on human body and establishment of tolerable upper intake levels for nutrients, effects of nutrients against toxic effects and toxicokinetics of toxicants, effects of dietary-source toxic substances on nutrients and their metabolism and nutrient processes, risk-benefit assessment of nutrients/food (components), and on these basis, proposing corresponding preventive and control measures. After more than 30 years of development, discipline system of nutritional toxicology has improved gradually, and it will play a more important role in safeguarding food safety and promoting human health.

Abstract:Objective In the present work, the chronic toxic effects of the transgenic rice T2A-1 carrying cry2A* gene was evaluated on Sprague-Dwaley rats through a 52-week feeding study. Methods One hundred and forty-four rats were randomly divided into 3 groups according to body weight. Transgenic rice T2A-1 and parent rice were formulated into diets at high levels of 60.75% during the growth period and 66.75% during the maintenance period, respectively. AIN-93 diet was used as a nutritional control. Animals were fed with the corresponding feed for 52 weeks. Cage-side observation, animal body weight, food intake, food utilization, hematology, serum biochemistry and urine analysis were carried out routinely. At the end of the administration, all survived animals were anatomized and histopathological examination were conducted. Results The main nutrient contents of the transgenic rice were similar to the parent rice. Throughout the experimental period, the trends in body weight, food intake and food utilization rate were similar in all groups. Although statistical significance was observed in some indexes of hematology, serum biochemistry and urine analysis of the transgenic rice groups as compared with the parent rice group, they were not considered as treatment-related. Histopathological examination showed some spontaneous lesions in all groups with no significant difference among them. Conclusion The result of the current 52-weeks chronic toxicity study of transgenic rice T2A-1 exerted no unintended adverse effects on rats.

Abstract:Objective This study was conducted to investigate the effects and mechanism of Moringa spp. polysaccharide extract on the occurrence and development of nonalcoholic fatty liver disease (NAFLD). Methods Fifty male rats were randomly divided into five groups (10 in each group):negative control group, model control group, low, medium and high dose group. From week 1, the negative control group and the model control group were given 10 ml/kg BW pure water by gavage once a day; each intervention group was given 10 ml/kg BW aqueous solution of Moringa spp. polysaccharide extract by gavage once a day until the 90th day. Blood samples were taken from the abdominal aorta and liver tissues after sacrifice. The total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), alanine aminotransferase (ALT), aspartate aminotransferase (ASL), superoxide dismutase (SOD) and malondialdehyde (MDA) of the serum were tested with the automatic biochemical analyzer. Serum interleukin 6 (IL-6), interleukin 1 (IL-1) and necrosis factor-α (TNF-α) were determined. Paraffin sections of liver tissue samples were stained with hematoxylin eosin. Results At the end of the experiment, there were statistically significant differences in body weight between the intervention group and the model control group(P<0.05). With the increase of dose, the serum index content(lipids, antioxidants, anti-inflammatory) in the intervention group was significantly different from that in the model control group (P<0.05), and tended to be the same as that in the negative control group. There also were statistically significant differences in LDL content between the high-dose group and the model control group (P<0.05). Microscopically, the model control group shown a variety of intrahepatic lesions, with deep lesions, severe hepatocyte steatosis. Although the hepatocytes in each intervention group were damaged to a certain degree, the types of lesion was less and less severe than that in the model control group. Conclusion The result of this study showed that Moringa spp. polysaccharide extract could significantly improve the lipid metabolism disorder in NAFLD, reduce the blood lipid level in rats, fight against the attack of oxygen free radicals, improve the inflammatory response and protect the liver. This protective effect may be achieved through antioxidant and anti-inflammatory pathways.

Abstract:Objective The aim was to study the genomic characteristics, virulence islands and genetic diversity of foodborne Listeria monocytogenes strains in Zhaoqing. Methods The whole-genome sequencing was carried out on 13 foodborne Listeria monocytogenes strains in Zhaoqing, and the assembled contings/Scaffolds were uploaded to the online analysis platforms Center for Genomic Epidemiology, Rast and VFanalyzer for genome annotation and virulence factor gene identification, while the genetic evolution of 25 domestic and foreign foodborne Listeria monocytogenes isolated strains obtained from National Center for Biotechnology Information(NCBI) were analyzed by whole genome-based single-nucleotide polymorphisms (wg-SNPs) method. Results The genome sizes of 13 foodborne Listeria monocytogenes strains ranged from 2.82-3.04 Mb, and the CG content ranged from 37.9%-38.1%. The isolates could be divided into 6 ST types (ST1, ST3, ST8, ST59, ST87, ST101), corresponding to 6 clonal complex groups (CC1, CC3, CC8, CC59, CC87, CC101). Among them, all the ST3 strains carried LIPI-3 virulence island gene, and all the ST87 strains carried complete LIPI-4 virulence island gene. The genetic evolution analysis of wg-SNPs showed that these 13 foodborne Listeria monocytogenes strains could be divided into two evolutionary branches, among which ST3 strains were located at the root of the evolutionary tree, differing from other ST strains in evolution. Conclusion The predominant foodborne Listeria monocytogenes strains in Zhaoqing were ST87 and ST3 strains with high virulence, which were the same as those in other parts of China. It was found that a ST87 strain carrying both LIPI-1 and LIPI-4 virulence island genes. The risk that the two ST-type virulent strains might cause infectious outbreaks in local area called for alarm and intensified monitoring.

Abstract:Objective A method was developed for the simultaneous determination of 11 organophosphate ester plasticizers in beverage by ultra high performance liquid chromatography-triple duadrupole tandem mass spectrometry (UPLC-MS/MS). Methods The sample was liquid-liquid extracted with acetonitrile, and purified by matrix solid dispersion using primary secondary amine (PSA). The compounds were separated on a C18 chromatographic column(2.1 mm×100 mm,2.5 μm)with the gradient elution of 0.1% formic acid aqueous solution and methanol as mobile phase. The analytes were detected by electrospray ionization source in the positive ion mode and multiple reactions monitoring mode. Results The result showed that the limits of quantification were in the range of 2.5-50 μg/L, the average spiked recoveries were in the range of 82.4%-113.0%, and the relative standard deviations (RSD) were in the range of 3.8%-17.6%. Conclusion This method was simple, rapid, sensitive, accurate, and could be used for the monitoring and supervision of organophosphates in beverage.

Abstract:Objective To establish a method for the simultaneous determination of 43 compounds of semi-volatile organic compounds (SVOCs) in drinking water by gas chromatography-mass spectrometry with automatic bulk solid phase extraction(SPE-GC-MS). Methods SVOCs in 1.0 L drinking water sample were enriched and purified by HLB solid phase extraction column, eluted by 2 ml ethyl acetate and 4 ml dichloromethane, purged and concentrated to 0.5 ml and volumed to 1.0 ml by ethyl acetate, separated by HP-5 ms ultra-inert capillary column(30 m×250 μm,0.25 μm), and then analyzed by selective ion scanning mode (SIM) coupled with GC-MS. Qualitative analysis was performed by retention time and characteristic ions, and quantitative analysis was performed by the internal standard method. Results Forty-three compounds of SVOCs were effectively separated and showed good linear relationship (r²≥0.995). The detection limits and quantitative limits of the method were 0.000 13-0.008 2 μg/L and 0.000 42-0.027 μg/L. The recoveries and precisions were 70.0%-138% and 0.3%-12.1%. Sixteen samples of different water were determined by the method, and ten compounds of SVOCs such as hexachlorobenzene, pentachloronitrobenzene and naphthalene were detected. Conclusion The method was sensitive and efficient, it was suitable for simultaneous detection of SVOCs in drinking water and provide a basis for public health emergencies.

Abstract:Objective To establish a duplex real-time polymerase chain reaction (PCR) method for simultaneous detection of the Ruvettus pretiosus and Lepidocybium flavobrunneum. Methods The specific primers and probes were designed base on cytochrome C oxidase subunitⅠ gene of Ruvettus pretiosus and Lepidocybium flavobrunneum, respectively. The perfromance of method was assessed, including sensitivity, specitivity and repeatability. The method was applied to detect the Ruvettus pretiosus and Lepidocybium flavobrunneum from fish products. Results The result indicated that duplex real-time PCR method was specific to Ruvettus pretiosus and Lepidocybium flavobrunneum. The method showed good linear relationship between Ct value and sample copies in 8.4×10⁵-8.4×10⁰ copies/μl, and the linear regression equation were y=-3.18x+41.0(R²=0.998 8) and y=-3.37x+44.5(R²=0.998 6) for Ruvettus pretiosus and Lepidocybium flavobrunneum, respectively. The limit of quantification (LOQ) was 16.8 copies. The relative standard deviation (RSD) of this duplex real-time PCR was 0.29%-0.84%, the RSD was 0.29%-0.84% and 0.29%-0.62% for Ruvettus pretiosus and Lepidocybium flavobrunneum, respectively. The Ruvettus pretiosus were identified using this method from 50 codfish products. Conclusion This duplex real-time PCR was a sensitive, sepecific and stable method. It would be useful for dete-ction of the Ruvettus pretiosus and Lepidocybium flavobrunneum.

Abstract:The establishment and improvement of mandatory food recall system is the realistic need and inevitable requirement to improve the government's governance and build the last stand for food safety. Based on the practical problems of mandatory food recall in China, this paper analyzes the legislative background, legal basis and recall procedures of the Food and Drug Administration (FDA) mandatory food recall system, then summarizes the main features of the FDA mandatory food recall, and finally clarifies its implementation. On the basis of the result, the specific proposals for improving China's mandatory food recall system are put forward, which have certain practical significance.

Abstract:Objective To investigate and assess the dietary nutrition status of puerperal women in urban areas of Xiamen. Methods 24 h dietary recall method was used to obtain the dietary status of puerperal women at postpartum 2nd,7th,30th and 90th days(n=200).The mean nutrients intakes were calculated by Chinese Food Composition(2004) and compared with DRIs. Results The intakes of animal foods(except milk) were too high, and the intake of beans, root and tubers, vegetables was too low; the energy intakes of the puerperal women at postpartum 2nd,7th,30th and 90th days were 2 146.7, 2 261.2,2 304.7,2 252.9 kcal, the protein intakes were 113.5,9.1,6.3,2.5 g, the energy from fat was 32.7%, 35.4%, 36.9%, 41.1% of the total energy, the energy from carbohydrates was 45.4%,41.7%,40.9%,38.7% of the total energy; the mean intakes of dietary fiber, calcium, iodine, vitamin A, vitamin C and vitamin B₁ were significantly lower than recommended nutrient intake. Conclusion The dietary pattern of puerperium women in Xiamen City was unreasonable with insufficient intake of some nutrients. No obvious differences were found on the nutrient intakes among them at four times points, and the dietary structure should be adjusted to ensure the nutritional balance of the puerperal women.

Abstract:Objective To establish the database of the ratio of food contact surface area/volume ratios (S/V) of different types of food contact material in beverage. Methods Different kinds of beverage consumed by Chinese population was collected, food contact surface area was calculated by direct measurement or 3D area measuring instrument. The ratio of S/V was obtained by combining contact area with food packaging volume. Results A total of 214 kinds of beverage were collected in this study. 72.0%(154/214)of food contact material(FCM) in contact with beverage was made of single material, the remaining 28.0%(60/214)was made of composite materials, mainly coated paper and coated tinplate. The mean S/V of FCM in contact with beverage was 11.29 dm²/kg, ranging from 4.26 to 64.32 dm²/kg. Further analysis found that 85.0%(182/214) of the S/V was greater than 6 dm²/kg, 73.4%(157/214) was between ≥6-12 dm²/kg. Conclusion The majority of S/V in contact with beverage was higher than 6 dm²/kg, a parameter used by European Food Safety Authority. Food contact S/V constructed by this investigation could decrease uncertainty in food contact material risk assessment.

Abstract:Objective To investigate the status of nutritional fortification labeling of pre-packaged foods, and to provide reference for the revision of food standard. Methods Cross-sectional survey method was conducted in 11 categories of food which were allowed to fortified in National Food Safety Standard for the use of food nutritional fortifier in foods(GB 14880-2012). A total of 3 760 label samples were collected during April to October in 2016, the number of fortified nutrients in each category food and its frequency were statistically analyzed. Results A total of 489 out of 3 760 samples were fortified with different nutrients, the total fortified frequency was 13.0% and there was a big difference between different categories of foods. Milk and dairy products, beverage products, grain and grain products had higher fortification proportion, which were 39.7%(160/403), 15.0%(151/1 006) and 14.0%(76/542), and prepared milk powder (110 samples) was all fortified, much higher than other types of food. A total of 411 samples in frozen drinks, fruit paste, soy milk, gum-based candy, rice products, cereal powder and its products were not fortified. The frequencies of fortified nutrients, vitamin A, D, E, B, calcium, iron and zinc were higher whereas phosphorus, γ-linolenic acid, lactoferrin, casein phosphopeptides was lower. Conclusion The overall fortification status of pre-packaged food was not optimistic. It was suggested that in the revision of GB 14880-2012, a systematic assessment should be made to decide which kind of food was suitable for food nutrition fortification carrier and which nutrient was suitable to be added, so as to improve the micronutrient intake of residents, and improve market variety and promote industrial innovation.

Abstract:Objective To investigate the radioactivity levels of tea-leaves in Lincang, Yunnan Province, estimate their influence on public health and accumulate base-line data of radioactivity levels of tea-leaves. Methods Radioactivity levels of 28 ripe tea-leaves and 15 fresh ones were measured in 2014 and 2015 with γ spectrometry method for analyzing radionuclides in biological samples. Results Natural (²³²Th, ²²⁶Ra, ⁴⁰K) and man-made (¹³⁷Cs) radioactive nuclides of the Pu'er tea held the lowest radioactivity levels[(0.95±0.99), (1.17±0.78), (571.33±9.10), <0.001 Bq/kg(fresh weight)]. Radioactivity levels of fresh tea-leaves presented seasonal characteristics and were higher in autumn [(0.72±0.12), (1.07±0.22), (161.16±13.35), (0.12±0.06) Bq/kg (fresh weight)]than spring[(0.52±0.11), (0.73±0.17), (133.35±30.74), (0.09±0.05) Bq/kg (fresh weight)]. Conclusion Radioactivity levels of ²³⁸U in ripe and fresh tea-leaves were below the limit of detection. Radioactivity levels of natural (²³²Th, ²²⁶Ra, ⁴⁰K) and man-made (¹³⁷Cs) radioactive nuclides in the tea-leaves were lower than the relevant national limits.

Abstract:Objective To investigate the contamination, virulence-associated genes and molecular typing of Vibrio vulnificus and Vibrio fluvibrio in aquatic products of Guangzhou City. Methods Vibrio vulnificus and Vibrio fluvibrio suspected isolates were further identified by VITEK-2 system and polymerase chain reaction (PCR). The virulence-associated genes of the Vibrio isolates were determined, and genotyping analysis was performed by enterobacterial repetitive intergenic consensus-polymerase chain reaction (Eric-PCR). Results The positive rates were 10.4% (31/298) and 5.0% (15/298) for Vibrio vulnificus and Vibrio fluvibrio. Three genotypes of Vibrio vulnificus were detected, including CB, EA and CA. The virulence-associated genes vfh and toxR of Vibrio fluvibrio were all positive, the detection rate of hupO was 60.0% (9/15) and vfp was 80.0% (12/15). Eric-PCR amplified 8-14 bands between 100-2 000 bp, and 15 Vibrio fluvibrio strains were divided into 5 groups and 11 types with a similarity coefficient of 0.8. Conclusion The contamination of Vibrio vulnificus and Vibrio fluvibrio in aquatic products in Guangzhou was serious, and most virulence-associated genes were present. Eric-PCR result showed that 15 Vibrio vulnificus strains were related to each other in genetic relationship, so prevention and control should be strengthened.

Abstract:Objective To understand Vibrio parahaemolyticus and Vibrio vulnificus contamination in raw ready-to-eat (RTE) aquatic products. Methods Using the principle of random sampling, 2 980 samples of raw RTE aquatic products were collected from restaurants, retail stores and wholesale markets in 13 regions of China, to monitor the contamination status of Vibrio parahaemolyticus and Vibrio vulnificus. Results The detection rate of Vibrio parahaemolyticus was 14.7%(437/2 980), the proportion of samples with >100 MPN/g was 2.9%(83/2 909), and the detection rate of Vibrio vulnificus was 3.5%(104/2 980). The detection rate of Vibrio parahaemolyticus, the proportion of samples >100 MPN/g and the detection rate of Vibrio vulnificus in samples from wholesale markets were higher than those from restaurants and retail stores. The detection rate of Vibrio parahaemolyticus, the proportion of samples with >100 MPN/g, and the detection rate of Vibrio vulnificus were the highest in the third quarter. The main causes of contamination included pollution in source areas, improper storage conditions and cross-contamination during processing. Conclusion There were Vibrio parahaemolyticus and Vibrio vulnificus contamination in raw RTE aquatic products, and its risk to health deserved enough attentions.

Abstract:Objective To determine the occurrence of polycyclic aromatic hydrocarbons(PAHs)in frying oils and to assess the health risk for the whole population. Methods 158 frying oils samples were collected during 2015 and 2017 from food safety risk monitoring program and 8 PAHs were analyzed. 14 PAHs were analyzed in 76 out of 158 samples. The health risk assessment in the whole population was estimated by margin of exposure(MOE)method. Results The detection rates of PAHs in frying oils were from 0.0%-100.0%, which 83.5%(132/158)for benzo(a)pyrene. The highest mean concentration of PAHs was 3.33 μg/kg for dibenz(a,h)anthracene, followed by benzo(a)anthracene (2.25 μg/kg) and chrysene (2.21 μg/kg) and benzo(a)pyrene (1.91 μg/kg). Chrysene was the predominant PAHs congener in 76 frying oils, consisting 18.6% of all 14 PAHs. The average dietary exposure to benzo(a)pyrene, benzo(a)pyrene+chrysene, benzo(a)pyrene+chrysene+ benzo(a)anthracene+benzo(b)fluoranthene, benzo(a)pyrene+chrysene+benzo(a)anthracene+benzo(b)fluoranthene+ benzo(k)fluoranthene+benzo(g,h,i)perylene+dibenz(a,h)antracene+indeno(1,2,3-cd)pyrene via frying oils for the whole population were 0.99,2.13,4.36 and 7.90 ng/kg BW, respectively. The corresponding MOEs were 70 707,9 812,7 982,2 025, which were much higher than 10 000. Conclusion MOEs due to ingestion of frying oils indicated a low concern for the whole population health at the mean and high level estimated dietary exposures, even in an extreme exposure scenario.

Abstract:Objective To collect and analyze the suggestions in re-evaluation for national food safety standard for food additives(GB 2760-2014), and provide suggestion to the revision of the standard. Methods The comments and suggestions for GB 2760-2014 were collected through the national food safety standard track and re-evaluation platform and the rationality and feasibility of the comments and suggestions were analyzed. The suggestions for the revision of GB 2760-2014 were put forward based on the comments and suggestions. Results About 574 comments and suggestions for GB 2760-2014 from 521 agencies or personal were collected from 2016 to 2018. All of the comments and suggestions were classified into different groups according to the content of GB 2760-2014. The result showed that most of the comments and suggestions focused on the appendix A, the provisions for useage of food additives and appendix E, food category system. The rationality and feasibility of the comments and suggestions were analyzed. Conclusion The national food safety standard for food additives were under revising, the scientific and rational comments and suggestions should be considered in the process of revision.

Abstract:Objective To analyze the epidemiological characteristics of mushroom poisoning in Jiangxi Province from 2012 to 2017,and provide scientific evidence for the control and prevention strategy. Methods The descriptive analysis was conducted on the incidence data of mushroom poisoning events in Jiangxi Province reported through foodborne disease outbreak reporting system from 2012 to 2017. Results A total of 120 mushroom poisoning events were reported with 463 poisoning cases and 19 deaths in Jiangxi Province from 2012 to 2017.The case fatality was 4.1%. The year with the most incidence was 2015, accounting for 33.3%(40/120) of the total. The majority of the mushroom poisoning events occurred during May to August. More mushroom poisoning events were reported in Jiujiang, Yingtan, Ji’an and Fuzhou Districts. The most of the mushroom poisonings occurred in the home sittings,accounting for 92.5%(111/120) of total number of mushroom poisoning,and the prevalence rate of the poisoning events caused by the mushroom in rural areas was higher than urban areas. The main cause of mushroom poisoning was eating by mistake. Poisonous mushroom were Amanita fuliginea and Chlorophyllum. Conclusion Poisonous mushroom poisoning was the main cause of death from foodborne illness in Jiangxi Province.

Abstract:Polyethylene terephthalate(PET)is widely used in the beverage packaging industry due to its superior performance and safety. The widespread use of PET has produced a large amount of waste PET. The recycling of PET can not only reduce health risk, but also reduce environment pollution and save resources. Recycled PET requires a systematic risk assessment before it can be authorized to be used as food contact material. The United States, the European Union, France and other countries and international organizations have established relevant safety assessment systems for recycled PET materials. This paper reviews the main method and differences of risk assessment of recycled PET materials for food contact in different countries or international organizations so as to provide reference for relevant work in China.

Abstract:Patulin (PAT), a toxic metabolite produced by molds is frequently found in numerous fruits and their products. Patulin poses serious threats to health of human beings by the enrichment in the food chain. Herein, the latest progresses on removing and detoxifying techniques of patulin including physical, chemical and biological strategies have been reviewed. Moreover, the degradation products of patulin and their safety after detoxification are discussed.