Facile synthesis of hydroxylated triazine-based magnetic microporous organic network for ultrahigh adsorption of phenylurea herbicides: An experimental and density-functional theory study.

Microporous organic networks (MONs) are highly porous materials that are particularly useful in analytical chemistry. However, the use of these materials is often limited by the functional groups available on their surface. Here, we described the polymerization of a sea urchin-like structure material at ambient temperature, that was functionalized with hydroxyl, carboxyl, and triazine groups and denoted as OH-COOH-MON-TEPT. A substantial proportion of OH-COOH-MON-TEPT was intricately decorated EDA-Fe3O4, creating a well-designed configuration (EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC) for superior adsorption of the target analytes phenylurea herbicides (PUHs) via magnetic solid-phase extraction (MSPE). The proposed method showed remarkably low limits of detection ranging from 0.03 to 0.22 ng·L-1. Experimental investigations and theoretical analyses unveiled the adsorption mode between EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC and PUHs. These findings establish a robust foundation for potential applications of EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC in the analysis of various polar contaminants.

Curcumin-mediated photodynamic treatment extends the shelf life of salmon (Salmo salar) sashimi during chilled storage: Comparisons of preservation effects with five natural preservatives.

The impact of curcumin-mediated photodynamic treatment (PDT) on the microbiological, physicochemical and sensory qualities of salmon sashimi has not been explored. Herein, this study aimed to evaluate the effects of PDT on the shelf-life quality of ready-to-eat salmon fillets during chilled storage (4 °C) in comparison with five widely investigated natural extracts, including cinnamic aldehyde, rosmarinic acid, chlorogenic acid, dihydromyricetin and nisin. From a microbial perspective, PDT exhibited outstanding bacterial inhibition, the results of total viable counts, total coliform bacteria, psychrotrophic bacteria, Pseudomonas spp., Enterobacteriaceae family, and H2S-producing bacteria were notably inactivated (p < 0.05) to meet the acceptable limits by PDT in comparison with those of the control group and natural origin groups, which could extend the shelf-life of salmon fillets from<6 days to 10 days. In the alteration of physicochemical indicators, PDT and natural extracts were able to maintain the pH value and retard lipid oxidation in salmon fillets, while apparently slowing the accumulation (p < 0.05) of total volatile basic nitrogen and biogenic amines, especially the allergen histamine, which contrary to with the variation trend of spoilage microbiota. In parallel, PDT worked effectively (p < 0.05) on the breakdown of adenosine triphosphate and adenosine diphosphate to maintain salmon fillet freshness. Additionally, the physical indicators of texture profile and color did not have obvious changes (p < 0.05) after treated by PDT during the shelf life. Besides, the sensory scores of salmon samples were also significantly improved. In general, PDT not only has a positive effect on organoleptic indicators but is also a potential antimicrobial strategy for improving the quality of salmon sashimi.

Estimating the burden of foodborne gastroenteritis due to nontyphoidal Salmonella enterica, Shigella and Vibrio parahaemolyticus in China.

To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 [95% confidence interval (CI) 2,320-5,663], and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.

Cationic covalent organic nanosheets for rapid and effective detection of phenoxy carboxylic acid herbicides residue emitted from water and rice samples.

Development of efficient and sensitive adsorbent for capturing phenoxy carboxylic acids (PCAs) from environmental and food samples is necessary because PCAs could threaten human health. Designing nanoparticle with multiple functional groups is beneficial to achieve the strong adsorption interaction and the specific recognition for target compound. In this paper, TpTGCl as an ionic covalent organic framework (ICOF), that could offer plenty of positive charges and hydrogen-bonding sites, was fabricated. TpTGCl achieved quicker, more sensitive enrichment for anionic PCAs. The analysis of binding affinity by density functional theory (DFT) demonstrated that PCAs bonded to TpTGCl primarily via electrostatic attraction, N  H···O and O  H···O, and C  H···π interaction. The quantitative approach indicated low limits of detection (0.016-0.036 ng·g-1 for rice and 0.43-0.78 ng·L-1 for water). Furthermore, successfully determining PCAs emitted from real samples indicated the applicability of TpTGCl.

The human health burden of non-typhoidal Salmonella enterica and Vibrio parahaemolyticus foodborne gastroenteritis in Shanghai, east China.

Information on the burden of disease due to foodborne pathogens in China is quite limited. To understand the incidence of foodborne gastroenteritis due to non-typhoidal Salmonella enterica and Vibrio parahaemolyticus, population survey and sentinel hospital surveillance were conducted during July 2010 to June 2011 in Shanghai, east China, and a model for calculating disease burden was established. The multiplier for gastroenteritis caused by these pathogens was estimated at 59 [95% confidence interval (CI) 30-102]. Annual incidence per 100,000 population in Shanghai was estimated as 48 (95% CI 24-83) and 183 (95% CI 93-317) cases for foodborne non-typhoidal salmonellosis and V. parahaemolyticus gastroenteritis, respectively, illustrating that bacterial gastroenteritis due to these two pathogens poses a substantial health burden. There is a significant difference between our simulated incidence and the data actually reported for foodborne diseases, indicating significant underreporting and underdiagnosis of non-typhoidal S. enterica and V. parahaemolyticus gastroenteritis in the surveillance area. The present research demonstrates basic situation of the health burden caused by major foodborne pathogens in the surveillance area. Enhanced laboratory-based sentinel hospital surveillance is one of the effective ways to monitor food safety in east China.

Determination of 107 Pesticide Residues in Wolfberry with Acetate-buffered Salt Extraction and Sin-QuEChERS Nano Column Purification Coupled with Ultra Performance Liquid Chromatography Tandem Mass Spectrometry.

A multi-residue method for the determination of 107 pesticide residues in wolfberry has been developed and validated. Similar pretreatment approaches were compared, and the linearity, matrix effect, analysis limits, precision, stability and accuracy were validated, which verifies the satisfactory performance of this new method. The LODs and LOQs were in the range of 0.14-1.91 µg/kg and 0.46-6.37 µg/kg, respectively. The recovery of analytes at three fortification levels (10 µg/kg, 50 µg/kg, 100 µg/kg) ranged from 63.3-123.0%, 72.0-118.6% and 67.0-118.3%, respectively, with relative standard deviations (RSDs) below 15.0%. The proposed method was applied to the analysis of fifty wolfberry samples collected from supermarkets, pharmacies and farmers' markets in different cities of Shandong Province. One hundred percent of the samples analyzed included at least one pesticide, and a total of 26 pesticide residues was detected in fifty samples, which mainly were insecticides and bactericide. Several pesticides with higher detection rates were 96% for acetamiprid, 82% for imidacloprid, 54% for thiophanate-methyl, 50% for blasticidin-S, 42% for carbendazim, 42% for tebuconazole and 36% for difenoconazole in wolfberry samples. This study proved the adaptability of the developed method to the detection of multiple pesticide residues in wolfberry and provided basis for the research on the risks to wolfberry health.

Studies on mechanism of free Nε-(carboxymethyl)lysine-induced toxic injury in mice.

Nε-(carboxymethyl)lysine (CML), which is a compound produced when food is processed, has aroused concern in recent years because of its potentially dangerous effects. This study aimed to investigate the mechanism of free CML-induced toxic injury in mice. The inflammatory cytokine tumor necrosis factor-α, transforming growth factor-ß, vascular cell adhesion molecule-1 mRNA expression levels of CML-infected mice liver and kidney tissues significantly increased. While CML receptor-receptor for advanced glycation end products (RAGE) protein expression in male mice liver tissue had a more significant change than the control group, there was no significant difference in other dose groups compared with the control group. In conclusion, the foodborne free CML can be induced by oxidative stress and immune response to liver and kidney tissue injury in mice. Additionally, the free CML may also bind to RAGE, which activates the downstream inflammatory pathway.

Potential efficacy of processing technologies for mitigating crustacean allergenicity.

Crustacean allergy has become a growing food safety concern at a global scale. In the past decades, various food processing approaches have been employed to develop food products with reduced allergenic potential. Thermal treatment can dramatically influence the allergenicity of crustaceans by either reducing or enhancing their allergenic potential. Maillard reaction, enzymatic and acid treatments have shown to be promising in mitigating crustacean allergenicity. Recently, novel processing technologies, namely high-pressure processing, high-intensity ultrasound, irradiation, pulsed ultraviolet light and hurdle technology have attracted special attention from the researchers and the food industry professionals owing to their benefits over the conventional methods. In this context, this review paper provides an updated overview of the current knowledge on how different food processing methods induce structural changes of crustacean allergens and, subsequently, influence their allergenic potential. Data on prevalence and clinical relevance of crustacean allergy are presented, as well as, the molecular characterization of crustacean allergens and the main analytical methods for their detection in processed foods.

Food Safety Knowledge, Attitudes and Behavior among Dairy Plant Workers in Beijing, Northern China.

The safety of milk and dairy products has always been one of the focuses of consumers, the food industry and regulatory agencies. The purpose of this study was to gain insight into the food safety knowledge, attitudes and behavior of dairy plant workers. A cross-sectional survey was performed between May and August 2015 in three dairy plants in Beijing, northern China. A total of 194 dairy plant workers were interviewed to collect information on food safety knowledge, attitudes and self-reported behavior. The 194 dairy plant workers interviewed showed a sufficient level of knowledge (mean score 34 on a scale from 0-58), perfect attitudes (mean score 17 on a scale from 0-18), and perfect behavior (mean score 38 on a scale from 8-40). Only 39% of workers correctly determined specific pathogens or diseases that could be conveyed through milk and dairy products. 24% of workers knew the correct method of washing hands. A significant positive association was observed between attitudes and knowledge (p < 0.001) as well as behavior (p < 0.01). Education level was positively and significantly associated with food safety knowledge, attitudes, and behavior (p < 0.05). Workers in dairy enterprises in northern China have relatively low levels of knowledge, yet satisfactory attitudes and behavior. The knowledge of microbial food hazards and hand hygiene remains an issue that needs to be emphasized in future training programs. Education level is a determinant of attitudes and behavior with regard to the proper handling of milk and dairy products.

Surveillance for foodborne disease outbreaks in China, 2003 to 2008.

Knowledge of implicated food vehicles and contributing factors derived from foodborne disease outbreak (FBDO) investigations allows consumers to be educated on decreasing high-risk behavior to reduce the risk of being affected by foodborne diseases. Food safety regulatory authorities also need summary of outbreak data, as these data indicate where the existing food supply system should be improved. To obtain information on epidemiology of FBDOs in China, FBDOs reported to the China National Foodborne Diseases Surveillance Network by 12 surveillance provinces that include 43% of the Chinese population was summarized. Between 2003 and 2008, 2795 FBDOs were reported, resulting in 62559 illnesses, 31261 hospitalizations, and 330 deaths. Outbreak size ranged from 2 to 464 cases, with a median of 14 cases. The outbreak rate had decreased from 1.37 per 1 million population in 2003 to 0.46 per 1 million population in 2008. Of the 2176 outbreaks with a single known etiology, bacteria (1051 outbreaks, 48%), man-made chemical hazards (550 outbreaks, 25%), and animal and plant toxins (536 outbreaks, 25%) were the main courses. Only one outbreak was caused by virus. Of the 1930 outbreaks with a single commodity, plant-based foods were the most common reported (930 outbreaks, 48%), followed by animal-based foods (590 outbreaks, 31%). Outbreaks most frequently occurred in private residences (32%), workplace cafeterias (21%), and restaurants (17%). The most common factor reported in the 2190 outbreaks with known contributing factors were improper cooking (510 outbreaks, 23%), contaminated ingredient (503 outbreaks, 23%), cross contamination (475 outbreaks, 22%) and improper storage (295 outbreaks, 13%). It is considered that FBDOs continue to be an important public health problem in China.

Health risks posed to infants in rural China by exposure to short- and medium-chain chlorinated paraffins in breast milk.

Chlorinated paraffins (CPs) are complex mixtures of synthetic chemicals found widely in environmental matrices. Short-chain CPs (SCCPs) are candidate persistent organic pollutants under the Stockholm Convention. There should be great concern about human exposure to SCCPs. Data on CP concentrations in human breast milk is scarce. This is the first study in which background SCCP and medium-chain CP (MCCP) body burdens in the general rural population of China have been estimated and health risks posed to nursing infants by CPs in breast milk assessed. The concentrations of 48 SCCP and MCCP formula congeners were determined in 24 pooled human milk samples produced from 1412 individual samples from eight provinces in 2007 and 16 provinces in 2011. The samples were analyzed by comprehensive two-dimensional gas chromatography electron capture negative ionization high-resolution time-of-flight mass spectrometry. The median SCCP and MCCP concentrations were 303 and 35.7ngg-1 lipid weight, respectively, for the 2007 samples and 360 and 45.4ngg-1 lipid weight, respectively, for the 2011 samples. The C10 and C14 homologs were the dominant CP carbon-chain-length groups, contributing 51% and 82% of the total SCCP and MCCP concentrations, respectively. There are probably multiple CP sources to the general Chinese population and numerous exposure pathways. The median estimated daily SCCP and MCCP intakes for nursing infants were 1310 and 152ngkg-1d-1, respectively, in 2007 and 1520 and 212ngkg-1d-1, respectively, in 2011. SCCPs do not currently pose significant risks to infants in China. However, it is necessary to continuously monitor CP concentrations and health risks because CP concentrations in Chinese human breast milk are increasing.

Associations between Urinary Excretion of Cadmium and Renal Biomarkers in Nonsmoking Females: A Cross-Sectional Study in Rural Areas of South China.

OBJECTIVES: The aim of this study was to systematically evaluate the relationship between urinary excretion of cadmium (U-Cd) and biomarkers of renal dysfunction. METHODS: One hundred eighty five non-smoking female farmers (aged from 44 to 71 years) were recruited from two rural areas with different cadmium levels of exposure in southern China. Morning spot urine samples were collected for detecting U-Cd, urinary creatinine (U-cre), ß2-microglobulin (ß2-MG), α1-microglobulin (α1-MG), metallothionein (MT), retinol binding protein (RBP), albumin (AB), N-acetyl-ß-D-glucosaminidase (NAG), alkaline phosphatase (ALP), γ-glutamyl transpeptidase (GGT) and kidney injury molecule-1 (KIM-1). Spearman's rank correlation was carried out to assess pairwise bivariate associations between continuous variables. Three different models of multiple linear regression (the cre-corrected, un-corrected and cre-adjusted model) were used to model the dose-response relationships between U-Cd and nine urine markers. RESULTS: Spearman's rank correlation showed that NAG, ALP, RBP, ß2-MG and MT were significantly associated with U-Cd for both cre-corrected and observed data. Generally, NAG correlated best with U-Cd among the nine biomarkers studied, followed by ALP and MT. In the un-corrected model and cre-adjusted model, the regression coefficients and R² of nine biomarkers were larger than the corresponding values in the cre-corrected model, indicating that the use of observed data was better for investigating the relationship between biomarkers and U-Cd than cre-corrected data. CONCLUSIONS: Our results suggest that NAG, MT and ALP in urine were better biomarkers for long-term environmental cadmium exposure assessment among the nine biomarkers studied. Further, data without normalization with creatinine show better relationships between cadmium exposure and renal dysfunction.

The Benefit Risk Assessment of Consumption of Marine Species Based on Benefit-Risk Analysis for Foods (BRAFO)-tiered Approach.

OBJECTIVE: To assess the net health effect caused by the consumption of specific marine species based on Benefit-Risk Analysis for Foods (BRAFO)-tiered approach. METHODS: Twenty species were collected from the Zhoushan Archipelago, China. Concentrations of n-3 long-chain polyunsaturated fatty acids, methyl mercury (MeHg), and dioxin-like compounds (DLCs) in the samples were analyzed for benefit risk assessment based on BRAFO-tiered approach. RESULTS: Based on the BRAFO-tiered approach, reference scenario (no intake) and alternative scenario (intake of specific species of 200 g/week) were determined. The exposure to MeHg/DLCs via alternative scenario of all studied species did not exceed provisional tolerable weekly/monthly intake. However, the adult population with high DLCs exposure in China would significantly exceed the upper limit of DLCs via an additional alternative scenario of some species such as Auxis thazard. The results of deterministic computation showed that alternative scenario of all studied species generated clear net beneficial effects on death prevention and child IQ gain. CONCLUSION: The alternative scenario of all studied species could be recommended to population with average DLCs exposure, and the reference scenario of species with relatively high DLCs concentration could be recommended to population exposed to high DLCs.

An evaluation of genotoxicity and cytotoxicity of melamine in combination with cyanuric acid at three mass ratios.

Melamine in combination with cyanuric acid has been considered to be more toxic than either melamine or cyanuric acid alone. The objective of this study was designed to evaluate the combined genotoxicity and cytotoxicity of melamine (M) and cyanuric acid (C) at three mass ratios (1:1, 1:2, 2:1). MC (1:1), MC (1:2), and MC (2:1) were evaluated for their potential genotoxic risk, at gene level by Ames test, and at chromosomal level by micronucleus test. In order to evaluate cytotoxicity in HEK-293 cells, the MTT assay was included. Western blot was also employed to investigate the renal injury molecule-1 (Kim-1) expression in HEK-293 cells exposed to MC. Neither genotoxicity at gene level nor at chromosomal level was observed for MC (1:1), MC (1:2), and MC (2:1). Based on MTT assay, three ratios of MC at 82.5 and 165 µg/mL slightly inhibited viability of HEK-293 cells (P<0.05). MC (1:1) at 41.25 and 82.50 µg/mL could elevate the Kim-1 expression in HEK-293 cells.

Exposure assessment to ochratoxin A in Chinese wine.

A rapid, sensitive, reproducible, and inexpensive method of high-performance liquid chromatography with fluorescence detection after an anion-exchange solid-phase extraction cleanup step for the analysis of ochratoxin A (OTA) in Chinese wine was developed. The average recovery rate and the average RSD of recovery were 97.47% and about 4%. The relative standard deviations of both the interday and intraday precision were 6.7 and 12.6%, respectively. The limits of detection and quantitation were determined to be 0.01 and 0.03 µg/L, respectively. A total of 223 samples from the major wine-producing areas of China were analyzed for OTA. OTA was detected at levels of 0.01-0.98 µg/L. The mean was 0.15 µg/L. Then, participants as representative inhabitants were invited to answer the designed questionnaire about the quantity and frequency of wine consumption. All data were simulated by the point evaluation for the risk assessment of OTA contamination from wine. Those results indicated that daily intake (DI) of OTA for the average adult consumer varies between 0.86 and 1.08 ng/kg bw per week, which was lower than all the reference standards. However, the DI value (4.38-5.54 ng/kg bw per week) in the high percentile (97.5) was slightly above 5% PTWI (100 ng kg(-1) week(-1)) of the JECFA. In conclusion, OTA exposure from Chinese wine has no risk of harm. This research will provide the scientific basis for determining the maximum limit of OTA content in Chinese wine.

Organochlorine pesticides and pyrethroids in Chinese tea by screening and confirmatory detection using GC-NCI-MS and GC-MS/MS.

One hundred and one tea samples including green tea, dark tea, scented tea, black tea, and oolong tea were screened and confirmed for the contamination of 31 organochlorine pesticides (OCPs) and 19 pyrethroids (PYs) by gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). 50 pesticides, 3 deuterium-labeled PYs, and 24 (13)C-labeled OCPs were separated well with the limits of detection (LODs) ranging from 0.02 to 4.5 µg/kg for GC-NCI-MS, and the positive samples were verified by GC-MS/MS with LODs of 0.1-5.0 µg/kg. High detection rates for some PYs, such as 63.4% for bifenthrin (not detected (ND)-3.848 mg/kg), 55.4% for λ-cyhalothrin (ND-3.244 mg/kg), 46.5% for cypermethrin (ND-0.499 mg/kg), and 24.8% for fenvalerate (ND-0.217 mg/kg), were found in the 101 tea samples. Endosulfan, DDTs, HCHs, and heptachlor, the persistent OCPs, were frequently detected with rates of 63.4% (ND-1.802 mg/kg), 56.4% (ND-0.411 mg/kg), 24.8% (ND-0.377 mg/kg), and 15.8% (ND-0.100 mg/kg), respectively.

Application of gas chromatography-mass spectrometry in analyzing pharmacokinetics and distribution of deltamethrin in miniature pig tissues.

OBJECTIVE: To characterize the pharmacokinetics and distribution profiles of deltamethrin in miniature pig tissues by gas chromatography-mass spectrometry (GC-MS). METHODS: Pharmacokinetics and distribution of deltamethrin in blood and tissues of 30 miniature pigs were studied by GC-MS after oral administration of deltamethrin (5 mg/kg bw). Data were processed by 3P97 software. RESULTS: The serum deltamethrin level was significantly lower in tissues than in blood of miniature pigs. The AUC0-72 h, Cmax, of deltamethrin were 555.330 ± 316.987 ng h/mL and 17.861 ± 11.129 ng/mL, respectively. The Tmax, of deltamethrin was 6.004 ± 3.131 h. CONCLUSION: The metabolism of deltamethrin in miniature pigs is fit for a one-compartment model with a weighting function of 1/C2. Deltamethrin is rapidly hydrolyzed and accumulated in miniature pig tissues.

Antioxidant and antigenotoxic activity of bioactive extracts from corn tassel.

This study is designed to evaluate antioxidant and antigenotoxic activities of corn tassel extracts (CTTs). The major bioactive components of CTTs include flavonoid, saponin and polysaccharide. The antioxidant properties of the three bioactive components of CTTs were investigated by Ferric Reducing Antioxidant Property (FRAP) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assays. The activities of the extracts were determined by assessing the inhibition of mutagenicity of the direct-acting mutagen fenaminosulf, sodium azide, and indirect-acting mutagen 2-aminofluorene using the Ames test (strains TA98 and TA100). The results showed that the extraction rates of flavonoid, saponin, and polysaccharide from the dried corn tassels were 1.67%, 2.41% and 4.76% respectively. DPPH and FRAP assay strongly demonstrated that CTTs had antioxidant properties. CTTs at doses of 625, 1250 and 2500 µg per plate reduced 2-aminofluorene mutagenicity by 12.52%, 28.76% and 36.49% in Salmonella typhimurium TA98 strain assay respectively and by 10.98%, 25.27% and 37.83%, at the same doses in Salmonella typhimurium TA100 assay system, respectively. 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay showed that the different concentrations of CTTs inhibited the proliferation of MGC80-3 cells in a dose-dependent manner (P<0.01). It is concluded that these integrated approaches to antioxidant and antigenotoxicity assessment may be useful to study corn tassel as a natural herbal material.