Abstract:Food microbiological risk assessment has always been the hot spot of the international food safety research. Foodborne pathogenic bacteria caused by food safety risk is a global problem, and the situation of the developing countries face more serious, the Chinese government attaches great importance to food safety work, constantly strengthen capacity building of the risk analysis system. Since 2010, the national food safety survey data suggest pathogenic microorganisms causing food poisoning, and report number has been higher than the damage chemical hazard and poisonous plants and animals. Therefore strengthen the microbiological quantitative risk assessment in order to reduce the gap with developed countries, from the national level is imperative.

Abstract:To analyze the effectof age and gender on egg allergens, and to explore the main epitopes of OM in chinese population.Methods 21 patients diagnosed as egg allergy were included, patients were divided into 3 groups:younger than 1-year-old (group A, 6 subjects), 2 to 3-years-old (group B, 7 subjects), and elder than 3-years-old (group C, 8 subjects). The serum of patients, the specific IgE of ovomuciod, ovalbumin, ovotransferrin and epitopes of ovomuciod were detected by immunodot-blots. Epitopes of ovomuciod were predicted by DNAStar. Results Immunodot-blots analysis showed that the numbers of serum samples which could react with ovomuciod were 2 in group A, 7 in group B and 5 in group C, respectively. All patients samples showed positive to ovalbumin. 3 patients IgE in group A could binding to ovotransferrin,as well as 6 samples in group B and 5 samples in group C.Conclusion Ovomuciod sIgE reactivity to egg allergens differed according to children's age. The DNAStar biological software was used to predict the epitopes of the egg type mucin which was low in Tianyin.

Abstract:Study the anti-androgenic effect of diethylhexyl phthalate (DEHP) and dibutyl phthalate (DBP).Methods According to Hershberger bioassay form OECD guideline, 6 weeks old male castrated SD rats were randomly divided into 16 groups, DEHP (35,0, 150,0, 500,1 000 mg/kg BW) and DBP (70,0, 250,0, 750,1 000 mg/kg BW ) were given by oral gavage, respectively. Meanwhile, corn oil was given by oral gavage as a negative control, and 3.0 mg/kg BW flutamide was given by oral gavage as a positive control for 10 consecutive days. In addition, 0.2 mg/kg BW testosterone propionate was given to each group by subcutaneously inject before gavage. In the end of test, animals were anesthetized, weight of glans penis, ventral prostate, seminal vesicles, levatorani-bulbocavernosus muscles, Cowper's glands were measured, testosterone and luteinizing hormone levels were measured. The dose-response were analyzed by benchmark does software. Results In comparison with negative control, weight of ventral prostate, levatorani-bulbocavernosus muscles and Cowper's glands were significantly decreased in the group of 250,0 and 1 000 mg/kg BW DEHP (P<0.05) , and weight of levatorani-bulbocavernosus muscles and Cowper's glands were significantly decreased in the group of 500,0 and 1 000 mg/kg BW DBP (P<0.05). Benchmark does of DEHP and DBP was 150.38 and 276.78 mg/kg BW.Conclusion DEHP and DBP had anti-androgenic effects in vivo and weight of levatorani-bulbocavernosus muscles and Cowper's glands are sensitive indexes.

Abstract:To assess the influence of rhLF expressed by mammary gland bioreactor of transgenic cows on immune function of rat offsprings.Methods According to the extended one-generation reproductive toxicity study protocol (OECD443), the experiment was divided into two groups, including control group and rhLF group. Diets containing 20% casein or recombinant human lactoferrin (rhLF) were fed to parental rats for 14 days prior mating and throughout pregnancy and lactation. Offsprings were randomly selected from each group and fed with corresponding diets from weaning to execution. Immune function of offsprings was assessed on PND0, PND21 and PND56. Results No significant differences were observed on hematology and percentage of lymphocyte subsets between various groups. PFC, the lymphocyte proliferative response and NK cell activity had no statistical difference(P＞0.05).Conclusion The results suggested that recombinant human lactoferrin exerts no adverse effect on the immune system of rat offsprings.

Abstract:The study aimed to explore the effect of developmental histomorphology of rat hippocampus after early stage yttrium exposure.Methods Rats were dietary exposed to yttrium nitrate under one of four doses (0,2,8,2 mg/kg BW, calculated based on Y³⁺) from GD0 to PND70, based on the developmental neurotoxicity. Six offsprings'(half male and half female)hippocampi per group were selected for histomorphology observation by the method of DAPI stain. Nerve special dyeing and HE staining was applied and subcellular structure was observed by transmission electron microscope.Results The amount of hippocampus glial cell apoptosis was significantly increased in 32 mg/kg BW group as compared with the control. No obviously visible change of nerve fiber and neuronal Nissl body in hippocampus was found. However, the impaired integrality of blood-brain barrier, swelling mitochondria and deposit sediment of dense particulate matter were found in 32 mg/kg BW group.Conclusion Rats exposed to yttrium of 32 mg/kg BW from GD0 to PND70 caused apoptosis of hippocampus glial cell, the impaired integrality of blood-brain barrier and the oxidative damage of mitochondria.

Abstract:To explore the sIgG antibody levels in 90 food and the correlation between common food sIgE in serum in patients with allergic respiratory diseases.Methods 178 patients with allergic respiratory diseases were detected 90 food sIgG and common food sIgE in the first affiliated hospital of Guangzhou Medical University from 2011.06-2014.10. Analyses were performed by using SPSS 19.0. Results The three leading positive food were milk and dairy products(42.63%), crustaceans (24.72%), meats and eggs (22.58%), the lowest were fruits (5.7%) and cereals (5.93%). The highest positive rate in food was eggs (70.79%), followed by white soft cheese (69.10%) and cow's milk (66.85%). The positive rate of sIgG antibodies in different age groups was varied in different categories and kinds of food. In 0-3 years old group, the highest positive rate of food item was milk and dairy products, and the positive rate gradually reduced as the age growing. On the contrary, the positive rate of crustacean showed rising trend after the age of 4. In the following categories of food , the positive rate of sIgG in male was higher than female:fruits, milk and dairy products in age group 0-3 years; cereals, fruits, meats and eggs in age group 4-6 years; crustacean in age group 7-16 years; legumes, vegetables, milk and dairy products, fishes, crustacean in age group ≥17 years. In the following categories of food, the positive rate of sIgG in female was higher than male:the other food in age group 4-6 years; milk and dairy products in age group 7-16 years. The above differences had statistical significance. A lot of food sIgG antibody levels were highly associated, mainly in milk and dairy products, fruits and vegetables. There were correlation between egg sIgG and albumen sIgE, milk and egg sIgG and sIgE(r_s=0.518,0.438,0.392,P<0.05).Conclusion There was certain distribution characteristics of food sIgG antibodies positive rate in different age and gender, food sIgG detection could be a supplement to food sIgE. Clinical diagnosis should be combined with gender, dietary habits and other factors to make guidance more reasonable for patients' diet adjustment.

Abstract:Using pulsed field gel electrophoresis for the separation of food poisoning strain for homology analysis, and providing a basis to find out the cause and traceability.Methods Samples from patients, food processing and leftovers were collected, isolated, identified and PFGE and antibiotic resistance analysis was performed.Results Four Salmonella Newport strains were detected in 13 samples, which were from the patient, the cooker, the remaining beef, and remaining duck. The PFGE patterns of the 4 strains were identical with the homology of 100%. 4 isolates had to the same resistance spectrum.Conclusion The food poisoning was caused by Salmonella Newport. PFGE typing techniques revealed epidemiological link between the strains, providing evidence for molecular epidemiological analysis and traceability of events.

Abstract:To investigate the contamination and health risks of heavy metals in edible marine shellfishes from China.Methods Statistical characteristics of the concentrations of six metals, i.e., Cu, Pb, Cd, Cr, As and Hg, in the edible shellfishes from China offshore waters were investigated, and their health risks were assessed using the target hazard quotient model recommended by US EPA, based on the available information regarding the metal concentrations reported in published literatures. Results The Kolmogorov-Smirnov test indicated that all the six metals had skewed concentration distributions. The average contents of Pb, Cd, Cr, As and Hg did not exceed the food standards. In this study, several independent samples tests showed that the concentrations of As, Cu and Cd were significantly different (P>0.05) among oyster, short necked clam, razor clam and mussel. In these four shellfishes, oyster had the highest levels of Cu and Cd, and razor clam had the highest level of As. No significant differences were observed for other three metals. In the Pearl River Estuary, Fujian coastal waters, the Yangtze River estuary-Zhejiang coastal waters, Shandong coastal waters and Bohai Bay, the non-carcinogenic risk levels from exposure to individual shellfish metal (including Cu, Pb, Cr, and Hg) were separately acceptable. However, the health risks from exposure to Cd in some shellfishes from Fujian coastal waters, Shandong coastal waters and Bohai Bay, and from exposure to As in some shellfishes from Fujian coastal waters, exceeded the acceptable levels. Although the health risk levels from exposure to multiple metals in shellfishes from Fujian coastal waters, Shandong coastal waters and Bohai Bay were unacceptable for children, the non-carcinogenic risks from six metals in other waters were within the safe level. The findings suggested that Cd and As were the key contributors to health risk from exposure to shellfish metals.Conclusion In China coastal waters, the concentrations of Cu, Cd and Cr in some shellfishes exceeded the food standard. The health risks from Cd and As were unacceptable in some shellfishes in some area, respectively. In this study, no serious heavy metal pollutions were found in the edible marine shellfishes, but the risk of multiple metals exposure in the shellfishes should be of concern.

Abstract:Guided by sectoral innovation system framework, the paper analyzed the current development of foods for special medical purpose (FSMP) in China by foreign-funded and domestic enterprises, along with the development of local research institutions and policies. After analysis, the paper pointed out that FSMP was still at the preliminary development stage in China. In addition, it argued that it was necessary to make greater efforts on construct sectoral innovation system to accelerate FSMP development in China.

Abstract:To compare the different effects of lentinan, pachymaran, tremella polysaccharide and their complex on cellular immunity of immuno-suppressed mice.Methods The function of T cells was detected by delayed type hypersensitivity (DTH) test, and the quantity of cytokines such as IL-2 and IL-6 in serum were detected using Luminex liquid protein microarray analysis system. The ratio and subtype of cells were detected by flow cytometry (FCM), and the proliferation of T cells was determined by using a colorimetric method with MTT. Results The ear swelling tends to be normal compared with the model group (P<0.05), and the lentinan group and polysaccharides complex group had the most significant difference (P<0.05). The tremella polysaccharide and polysaccharide complex could upregulated the level of IL-6 in serum of immuno-suppressed mice (P<0.05). All the polysaccharides had the tendency of enhancing the ratio of regulatory T cells (Tregs) in blood, the difference in tremella polysaccharide and polysaccharide complex had statistical significance comparing with model group(P<0.05). All test samples had function of restoring the ratio of Th1/Th2 cells in peripheral blood in immuno-suppressed mice (P<0.05), the function of polysaccharide complex was the most significant among them. All four polysaccharides had the tendency of restoring the ratio of splenic T and B cells in immuno-suppressive mice, the most obvious trend of which was polysaccharide complex. All the four polysaccharides had the tendency of promoting proliferation of splenic T cells, the difference of lentinan and polysaccharide complex was statistically significant comparing to the model group (P<0.05).Conclusion Lentinan, pachymaran, tremella polysaccharide and their complex could restore the cellular immunity in immuno-suppressed mice, and the complex was the best.

Abstract:A ultra performance liquid chromatography-hybrid triple quadrupole linear ion-mass spectrometric method(UPLC-QqQLIT) was established for determination of 8 penicilins ( penicillin G, ampicillin, penicillin V, amoxicillin, nafcillin, cloxacillin, oxacillin and dicloxacillin ) and their penicilloic acids (penicilloic acid G , ampicilloic acid, penicilloic acid V, amoxicilloic acid, nafcilloic acid, cloxacilloic acid, oxacilloic acid and dicloxacillioic acid) in milk products. The 8 penicilins and there penicilloic acids in milk products were surveyed.Methods The 8 penicilins and penicilloic acids in milk products were extracted by water in super-sonic instrument, proteins were precipitated by acetonitrile and degreased fat by n-hexane with liquid-liquid extraction, then the purified solution was concentrated by nitrogen, dissolved with acetonitrile-water (10∶90, V/V) and cleaned by 0.22 μm millipore filter. The filtrate was detected by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), identified by electrospray ionization (ESI) in positive mode using multiple reaction monitoring, and quantified with external standards. Information dependent acquisition scan function (IDA) combined with enhanced production scan (EPI) was used to confirm the 8 penicilins and their penicilloic acids. Results The calibration curves of 8 penicilins and penicilloic acids showed good linearity in the range of 1.0-200 μg/L with correlation coefficients of 0.999 1-0.999 9. The detection limits of the method were 0.01-0.05 μg/kg for milk powder and 0.002-0.010 μg/kg for liquid milk. The recoveries of three spiking levels ranged from 80.0% to 110.0%, and the relative standard deviations (RSD) were 0.16%-7.06%.Conclusion The method for determination of 8 penicilins and penicilloic acids in milk products by UPLC-QqQLIT was of operation convenience, less interference from impurities and good accuracy, which could meet the requirements for the determination of 8 penicilins and penicilloic acids residues in milk products.

Abstract:To evaluate the PetrifilmTM Salmonella express system of 3MTM company following the standards and specifications.Methods The inclusiveness and exclusivity of the PetrifilmTM Salmonella express plate were evaluated using 64 Salmonella strains of 53 serotypes and 30 non-Salmonella strains. Different Salmonella detection systems were compared and evaluated by parallel tests of a wide range of food samples inoculated with Salmonella with the GB method. Results The growth rates of 64 Salmonella strains on four selective media were significantly different (P<0.05), and the growth rate of 30 non-Salmonella also showed difference. Using different Salmonella selective enrichment broth-selective agar combination, the detection rate showed significant difference at 10-1 cfu/25 g level (P<0.05),and the highest detection rate was found by using RV(R10)-3M express plate. The using of two different selective enrichment broths and two selective agars (such as the GB method) could significantly improve the detection rate at 10-¹cfu/25 g level in food samples (P<0.05).Conclusion The PetrifilmTM Salmonella express system of 3MTM company was a rapid,convenient Salmonella detection kit and should be promoted in food microbiogy testing labs since it showed the same level of accuracy with the GB method in a wide range of food samples.

Abstract:To establish a novel analytical method to analyze 15 glucocorticoids residues in pork by high performance liquid chromatography-Q-time of fight mass spectrometry.Methods The analytes were extracted from the samples with acetonitrile and water. After cleaned up with C₁₈ SPE column, samples were analyzed by HPLC-Q-TOF-MS with an electrospray interface in positive ionisation mode. The validation of the method consisted of limit of detection (LOD), limit of quantification (LOQ), precision and recovery. The accurate mass database was established and the accurate mass of characteristic fragments indicated the structures of the fragments. Results The LODs for 15 validated compounds were 0.1-1 μg/kg, and the average recoveries were in the range of 47.1%-110.3% with the relative standard deviations (RSD) <20% (n=6).Conclusion The results indicated that this method was simple, rapid, sensitive and suitable for the determination of glucocorticoids in pork.

Abstract:To establish a method for determination of 11 bactericides and fipronil residues in fruits by liquid chromatography tandem mass spectrometry.Methods The samples were extracted by acetonitrile and then homogenized. The supernatants were separated after centrifuge and nearly dried with rotary evaporation. After the solid phase extraction of amino cartridge, the eluent was dried-up by the rotary evaporation. The analytes were dissolved by the mobile phase and determined by liquid chromatography tandem mass spectrometry. The conditions of separation and mass spectrometry were optioned. Results The relative standard deviations of detection were 4.7%-9.4%, the spiked sample recoveries were 78.6%-107.4%. The limits of quantification and detection were 0.002-2.2 and 0.000 4-0.66 μg/kg.Conclusion The method is simple, accurate, sensitive and could meet the determination requirements of pesticide residues in foods.

Abstract:To extract tetrodotoxin with immunoaffinity cartridge, develop an ultra fast liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS) method for determination of tetrodotoxin in fish muscle and liver, and provide proof for detection TTX in aquatic products.Methods Tetrodotoxin was extracted by 1% acetic acid methanol, supernatant added with PBS buffer was loaded on immunoaffinity cartridge, the eluent was blow-dried by nitrogen and dissolved in constant volume. Then the sample was separated on a Zic-Hilic column with 10 mmol/L ammonium formate-0.1% formic acid and acetonitrile as mobile phase by gradient elution. Detection was carried out by multiple reaction monitoring. Results Tetrodotoxin had a good linear result in the range of 1.0-1 000.0 ng/ml with detection limit of 0.3 μg/kg in muscle and 0.2 μg/kg in liver respectively. The recovery was 52.4%-72.6%.Conclusion This method has excellent specificity, good effect of extraction and without matrix inhibition effect. The assay is suitable for trace detection of tetrodotoxin in fish muscle and liver.

Abstract:A method for determination of choline in infant formula by HPLC-ELSD was optimized.Methods The separation was operated on an analtical Agilent ZORBAX 300 SCX column(4.6 mm×250 mm,5 μm)with water (containing 30 mmol/L triethylamine):acetonitrile (80∶20, V/V) as mobile phase.Results The limit of detection was 4 μg/ml. The calibration curve was linear (r=0.998 1). The relative recoveries were 94.98%-100.9%, and relative standard deviations of intra-day and inter-day precision were 2.75% and 3.12%, respectively.Conclusion The method was simple and fast. Compared to the traditional method, analysis time was shorter, and the peak shape of choline is more narrow and symmetrical.

Abstract:This paper reports an ultra performance liquid chromatography (UPLC) method for determination of 4 kinds of phytosterols (brassicasterol, stigmasterol, campesterol and β-sitosterol) in edible vegetable oil.Methods Edible vegetable oil samples were completely saponificated by glacial acetic acid, pH was adjusted to 6.0-7.5, then used ethanol to constant volume and freezing centrifuged to harvest supernatant. The analytical separation was performed on an Endoavorsil C₁₈ (100 mm×2.1 mm, 1.8 μm) chromatographic column with the isocratic elution using methyl alcohol and detected by photo-diode array detector at 205 nm. Results The linearity ranges were 20-200 μg/ml for β-sitosterol, stigmasterol and brassicasterol and 10-100 μg/ml for campesterol. The limits of detection were 23.2 μg/g for brassicasterol, 18.8 μg/g for stigmasterol, 18.6 μg/g for campesterol, and 23.8 μg/g for β-sitosterol. The quantitation limits were 77.5 μg/g for brassicasterol, 62.8 μg/g for stigmasterol, 62.2 μg/g for campesterol, and 79.4 μg/g for β-sitosterol. The average recoveries of spiked samples were 84.7%-100.7% and the RSD of method (n=6) was less than 3%.Conclusion The method was steady, simple, accurate and sensitive. It could be used to simultaneous detect 4 kinds of phytosterols in edible vegetable oil.

Abstract:To investigate the chromium contamination of sea worm jelly in Xiamen market and to propose the preventive measures against chromium contamination of sea worm jelly based on analysis of the source. Methods A total of 81 samples of sea worm jelly and 9 samples of polypide were collected in Xiamen market from 2012-2014 and 6 samples of Phascolosoma esculenta, silt and seawater were collected from Ningde. The concentrations of Cr in the samples were determined by graphite furnace atomic absorption spectrometry according to GB/T 5009.123-2003. Results The chromium content of 81 samples were 0.024-17.6 mg/kg, the average content was 2.17 mg/kg,and the median was 1.33 mg/kg. The qualified rate was 58.0%. The concentration of Cr in sea worm jelly was changed from 1.33 to 5.35 mg/kg after adding gelatin. The contents of Cr in the Phascolosoma esculenta, silt and seawater from Ningde area were 2.67-2.70,8.5-77.9,0.038-0.046 mg/kg, respectively. Conclusion The chromium contamination in the sea worm jelly was severely in Xiamen. Supervision and monitoring on the raw materials, production, sales of the sea worm jelly should be strengthened to ensure food safety.

Abstract:As a supplement of the national food safety standards, 159 provincial food safety standards has been released since 2009 by the local health administrative departments in China. Through the investigation and research of all the provincial food safety standards, this paper analyzes the main existing problems and puts forward related suggestions on the management of the provincial food safety standards.

Abstract:The aim of this study was to evaluate the identification accuracy and to acquire a preliminary analysis for antimicrobial resistance of Pseudomonas aeruginosa isolated from bottled water in 21 provinces of China in 2013.Methods PCR method based on eta2 and oprI genes was used in the rapid verification for Pseudomonas aeruginosa isolates, and biochemical method with Vitek GN cards was used as reference method. Broth microdilution method was used to obtain minimal inhibitory concentrations (MICs) of all 531 strains to 12 antibiotics belonging to 8 categories. Results eta2 and oprI genes were validated by target bands and eta2 was more specific. The results of biochemical test showed that the identification accuracy of all provinces was 100%. PCR method using two genes could achieve an accuracy over 95% with few false negative results. Among 531 Pseudomonas aeruginosa strains from 21 provinces in China, there were 62 (11.68%) drug resistanta isolates in all, and these strains showed the highest resistance to polymyxin B (5.27%), followed by aztreonam (4.14%) and meropenem (3.01%). 230 (43.31%) and 135 (25.42%) of the strains tested were intermediate to ticarcillin-clavulanate and ticarcillin respectively.Conclusion The accuracy of Pseudomonas aeruginosa identification in all provinces was qualified, and PCR test could be a rapid and accurate screening method for detecting Pseudomonas aeruginosa in combination with traditional biochemical methods. Compared with clinical isolates, Pseudomonas aeruginosa isolated from bottled water remained at low drug resistance level, but there was a potential tendency that strains may become more resistant to ticarcillin-clavulanate and ticarcillin to some degree, so regular monitoring was necessary to recognize antimicrobial resistance characteristics and tendency of Pseudomonas aeruginosa isolated from bottled water.

Abstract:The aim of this study was to measure the contents of lead, cadmium, mercury and arsenic in six kinds of foods, evaluate its contamination condition in Shaanxi Province, and to provide evidence not only for the evaluation of foods safety but also for the effective measures to control heavy metal contamination.Methods Inductively coupled plasma mass spectrometer was employed to measure lead and cadmium contents, hydride generation-atomic fluorescence spectrometry was used to measure arsenic contents, and mercury vapourmeter was used to measure mercury contents. One factor contamination index and comprehensive pollution indices were employed to evaluate the metal contamination of different kinds of foods. Moreover, the health risk of heavy metals exposure from foods was described. Results In six kinds of foods in Shaanxi, the lead and mercury contents in meat were the highest at 0.049 0 and 0.003 3 mg/kg respectively. The contents of cadmium and arsenic in grain crop were the highest at 0.025 0 mg/kg. The contents of lead, cadmium, mercury and arsenic measured by single contamination index and comprehensive contamination index were safe and clean, and the margins of safety of lead, cadmium, mercury and arsenic in six kinds of foods were below one.Conclusion Six kinds of foods were contaminated by lead, cadmium, mercury and arsenic, but the content were low. The risks of these heavy metals are acceptable, and the foods are all safe to eat.

Abstract:To explore the ethyl carbamate level in the spirits and assess the health risk of ethyl carbamate exposure among Chinese population.Methods The @Risk software was introduced and probabilistic assessment method was adopted to assess the risk of ethyl carbamate exposure from spirits consumption. The ethyl carbamate concentration data was derived from national food safety risk surveillance system between 2010 and 2011, and the spirits consumption data of population aged 18 and above was collected in Chinese nutrition and health survey 2002.Results The mean value of ethyl carbamate in spirits were 0.072 mg/kg. The average intake of ethyl carbamate and the margin of exposure (MOE) value among people aged 18 and above were 8.09 ng/kg BW per day and 37 083 respectively. However, the average intake of spirits consumers was 159.99 ng/kg BW per day and the margin of exposure value was 1 875. The probability of individual margin of exposure exceeding the level of public health concern was 0.052 and 0.455 for the whole population aged 18 and above and spirits consumers respectively.Conclusion For the people aged 18 and above, the health risk of ethyl carbamate exposure from spirits was of low concern, however, there was a quite high health risk caused by ethyl carbamate intake among spirits consumers.

Abstract:To study the rare earth elements (REEs) concentration level in brick tea, and evaluate REEs dietary intake level and potential health risks in brick tea in Chinese adults.Methods The concentrations of REEs in brick tea samples were detected by inductively coupled plasma mass spectrometry (ICP-MS). The consumption of brick tea in Chinese adults was investigated in 2014-2015 by 24 hour dietary retrospective method. Based on the deterministic assessment model, the dietary intake of REEs in brick tea by Chinese adults was calculated.Results The violation rate of REEs in brick tea was 74%, the range of concentration was 0.10-10.35 mg/kg, the average was 3.41 mg/kg, and the median was 3.10 mg/kg. The average concentrations of Ce, La, Y, and Nd (0.74,0.43,0.35, and 0.30 mg/kg, respectively) were higher than the other 13 REEs. In brick tea consumption population, average exposure of REEs was 0.668 μg/kg BW, only accounting for 1.13% of ADI. The high consumption (P95) exposure of REEs was 2.302 μg/kg BW per day, accounting for 3.90% of the ADI. The average exposure of Ce, La, Y and Nd (0.178,0.104,0.082 and 0.073 μg/kg BW, respectively) was higher than the other 13 REEs, almost accounting for 65% of the total REEs exposure.Conclusion The exposure of REEs in brick tea by Chinese adults was considerably below the ADI and any health risk that would be expected to occur at this exposure level was negligible.

Abstract:To apply the threshold of toxicological concern (TTC) approach to the risk assessment of dimethyl 1,2-benzenedicarboxylate (DMP) and 1,2-benzenedicarboxylic acid diethyl ester (DEP).Methods Cramer schematic diagram and Toxtree software were used to classify DMP and DEP into Cramer systems. DMP and DEP exposure in general population as well as in different age groups was estimated by using data from the Chinese National Nutrition and Health Survey in 2002 and data of DMP and DEP contents in 24 kinds of foods. TTC decision tree approach was used for risk assessment and the exposure was compared with the corresponding TTC value. Results DMP and DEP belongs to class I Cramer and its TTC value was 30 μg/kg BW. The maximum dietary exposures of general population and four age groups were 2.43 and 1.72 μg/kg BW respectively, which are 8.10% and 5.72% of their TTC value. Among 8 age groups, the maximum dietary exposures of DMP and DEP are 2.01 and 1.44 μg/kg BW. These exposure values accounted for 6.71% and 4.79% of TTC values.Conclusion The dietary exposure of DMP and DEP in Chinese population was low and no health concern was required.

Abstract:To identify the cause of poisoning, take effective intervention promptly and to provide scientific evidence to prevent and control similar epidemic diseases in the future.Methods Cases were screened by verifying diagnosis, interviewing and searching in the company. Exposure patterns and factors were identified by applying descriptive epidemiology. The corelation between the factors and diseases was analyzed through retrospective cohort study. Samples of feces, vomitus and food remains were detected.Results Retrospective cohort study indicated fried squid with green peppers and tofu roll salad for lunch on 18^th were suspicious for the 37 cases. Vibrio parahaemolyticus were found in both feces and food remains.Conclusion The outbreak was caused by squid contaminated by Vibrio parahaemolyticus and cross contamincation occured in the process of making tofu without adequate sterilization treatment.

Abstract:Rare earth is heavy metal element, with broad-spectrum biological toxicity and low dose accumulation poison effect. The quality issue of rare earth in agricultural products has received much attention, lately. There is a lot of discussions and controversies on the high content of rare earth in tea. Basing on the results of published literature, this paper mainly focuses on the following issues:(1)The effect of constant rare earth intake from tea on human health and its accumulation in human body. (2) It is necessary to set standard on the use of rare earth in agricultural products, that is' limit on the use of rare earth in plant food (GB 13107-1991). This is not only the need of international liability, but also the request to guarantee the safely of agricultural products. (3)The main reason of high rare earth content in tea is the use of rare earth fertilizer, especially rare earth leaf fertilizer. Tee tree can highly selectively absorb rare earth and convert it to its own component due to its special biological characteristics. This may account for the high content of rare earth in tea and soil. The content of rare earth in tea is the combination of the innate and exogenous rare earth in the soil. Secondly, there is a huge difference between rare earth products and plant growth regulator. It is a big mistake to use rare earth products on agricultural products. (4) The key to solve the high content of rare earth in tea is to completely eradicate the use of rare earth fertilizer in tea production. It is good for both the soil and tee tree to cut off the source of rare earth.

Abstract:In the past few years, the whole genome sequencing (WGS) analysis has shown its great value and potentials in the field of microbial heredity and variation characteristics, evolution and source tracking. This paper reviews the basic principles of WGS and introduces two main methods to interpret and analyze the WGS sequencing data by wgSNP and wgMLST. Then, the main characteristics of WGS such as discriminatory ability and sensitivity were compared with the other common molecular typing methods of PFGE and MLST. Also, it's illustrated that the current state-of-art of the WGS applied to the foodborne disease surveillance, identification of outbreaks and source tracking. Finally, the advantages of the WGS and the prospective of its future application in the foodborne disease surveillance and identification of outbreaks were briefly expounded.