Regioselective -Trideuteromethylation of Tautomeric Polyaza Heterocycles.

Methods for regioselective -trideuteromethylation of tautomeric polyaza heterocycles are highly sought-after. Disclosed herein is an -trideuterated methylation reaction of imidazoles and pyrazoles with high regioselectivity and deuterium purity using easily available CFSOCD as the -CD source. This method enables the easy synthesis of important deuterium-labeled azoles, including dimetridazole-, ipronidazole-, hydroxy dimetridazole-, and ronidazole-.

Assessment of dietary exposure of young Chinese children to aluminium residues.

The aim of this study was to assess the Al dietary exposure of young Chinese children aged 0-3 years via formulae, complementary foods and wheat-based foods. Al residue data were obtained from the national food contamination monitoring programme from 2013 to 2016, encompassing 13,833 samples of 12 food items with a detection rate of 76.0%.

Risk assessment of dietary exposure to aluminium in the Chinese population.

In order to address the issue of excessive intake of aluminium (Al) from Al-containing food additives in the Chinese diet, this study conducted a dietary exposure assessment of Al in the general population based on the national surveillance data of Al content in foods and national food consumption data. It was found that the mean dietary exposure of the whole Chinese population to Al from Al-containing food additives was 1.795 mg kg bw week, not exceeding the PTWI, while high dietary exposures (e.

Dietary Exposure to Benzyl Butyl Phthalate in China.

Objective: Benzyl butyl phthalate (BBP) is a plasticizer used in food contact materials. Dietary exposure to BBP might lead to reproduction and developmental damages to human. The present paper was aimed to assess the health risk of BBP dietary exposure in Chinese population.

The Survey of Cronobacter spp. (formerly Enterbacter sakazakii) in Infant and Follow-up Powdered Formula in China in 2012.

Objective: To determine Cronobacter spp. contamination in infant and follow-up powdered formula in China.

Methods: All of 2282 samples were collected from the retail markets in China from January 2012 to December 2012, and analyzed for Cronobacter spp.

Concentration of di(2-ethylhexyl) phthalate (DEHP) in foods and its dietary exposure in China.

Di(2-ethylhexyl) phthalate (DEHP) is a common plasticizer used in food contact materials that has been reported as an endocrine disruptor. In the present study, DEHP concentrations were analyzed in foods in order to determine dietary exposure among the Chinese population, including the general population (aged 2-100) and four age group, that is children aged 2-6, adolescent aged 7-12, young people aged 13-17 and adults aged 18 years old and above. 1704 food samples were collected during 2011-2012 and categorized into 12 food groups which covered major foods in China.

[Development of a model diets for consumers with high exposure to food chemicals].

Objective: To develop and verify a model diet for consumers with high exposure to food chemicals.

Methods: Based on the assumption that a person might consume average amounts of several different foods but only two or three at high levels, a model diet were put forward to calculate the high exposures to certain food chemical.Important parameters of this model were selected by comparing the outputs of this model with those of a reference model-semi-probabilistic model that is based on individual data.

Simultaneous determination of 17 phthalate esters in edible vegetable oils by GC-MS with silica/PSA-mixed solid-phase extraction.

A quantified method for the determination of 17 phthalate esters (PAEs) in edible vegetable oil by GC-MS with the pretreatment of acetonitrile extraction and silica/N-(n-Propyl)ethylenediamine-mixed SPE column was established. By the quantification of internal standard of D(4)-di(2-ethylhexyl) phthalate, a good linearity range of related 17 PAEs was observed. The correlation coefficient was ranged at 0.

[The determination of phthalic acid esters in edible vegetable oils by gas chromatography-mass spectrometry].

Objective: We aimed to establish a quantified method for the 17 phthalate acid esters (PAE) in edible vegetable oil by gas chromatography-mass spectrometry (GC-MS) with the pretreatment of acetonitrile extraction and silica/N-(n-propyl)ethylenediamine (silica/PSA) mixed solid phase extraction column and evaluated the PAE of 25 edible oil samples from supermarkets in Hangzhou city.

Methods: The internal standard solution (D4-DEHP) was added in edible vegetable oil sample. The analytes were extracted by acetonitrile with 1 min vortex, and centrifuged at 3050×g for 5 min.

A survey of 16 rare Earth elements in the major foods in China.

Objective: The aim of this survey was to investigate the level of contamination of the most consumed foods in China with 16 rare earth elements (REEs), and to provide the basic data for establishing and revising food safety standards for REEs.

Methods: Sixteen REEs in foods were measured by inductively coupled plasma-mass spectrometry (ICP-MS) in the labs of the Centers for Disease Control and Prevention of four provinces and two municipalities, during 2009-2010.

Results: 1 231 samples were analyzed and 19 121 concentration data of 16 REEs were collected.

[Survey and analysis of ethyl carbamate in commercial fermented foods in Hangzhou in 2010].

Objective: To observe the ethyl carbamate concentrations in different commercial fermented foods in Hangzhou in 2010.

Methods: In 2010, 237 commercial fermented food samples of eight categories, including yellow wine, white spirit, wine, beer, cooking wine, sauce, vinegar and fermented bean curd, were purchased from 3 different size markets respectively in Hangzhou. The ethyl carbamate was measured by gas chromatography-mass spectrometry in selection ion mode, after the samples were coupled with D5-ethyl carbamate, and purified by diatomite solid phase extraction column.

Study on migration of melamine from food packaging materials on markets.

Objectives: To study the migration of melamine into foods from plastic food packaging materials and dairy product containers commonly used in China.

Methods: 37 samples were collected from the market. The EU migration testing conditions were adopted with distilled water, 3% acetic acid, n-hexane and 15% ethanol being chosen as the simulating solutions.

Simultaneous determination of nonnutritive sweeteners in foods by HPLC/ESI-MS.

Nonnutritive sweeteners are the low calorie substances used to replace sugar and other caloric ones. Determination of these sweeteners in foods is important to ensure consistency in product quality. In this study, seven artificial (aspartame, saccharin, acesulfame-K, neotame, sucralose, cyclamate, and alitame) and one natural sweetener (stevioside) were simultaneously determined in different foods using high performance liquid chromatography (HPLC) coupled with electrospray ionization mass spectrometric detection (ESI-MS).

[A new method for safety monitoring of natural dietary supplements--quality profile].

Objective: A new method for safety monitoring of natural dietary supplements--quality profile was proposed. It would convert passive monitoring of synthetic drug to active, and guarantee the security of natural dietary supplements. Preliminary research on quality profile was completed by high performance liquid chromatography (HPLC) and mass spectrometry (MS).

[National continuous monitoring on the content of lead in preserved eggs from 2000 to 2006].

Objective: To investigate the pollution level and development trend of lead in the preserved egg in our country.

Methods: By the national food contamination monitoring system and under the strict analysis quality control, the content of lead in the preserved eggs was analyzed according to the national standard method (GB/T 5009.12-2003) in fourteen provinces from 2000 to 2006.