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1.
Food Chem Toxicol ; 190: 114832, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38908816

RESUMEN

Rare Earth Elements (REEs) have been implicated in potential health effects. However, the health risk of REE exposure among tea drinkers in China remains poorly understood. This study aimed to characterize the concentration of REEs in different tea categories and evaluate the associated health risks for tea consumers in China. By analyzing the content of 16 REEs in 4326 tea samples from China, the exposure level of REEs to the general population was estimated. The content of these 16 REEs was similar across six types of tea, with oolong tea exhibiting the highest levels. The concentration of light rare earth elements (LREEs) in six types of tea was higher than that of heavy rare earth elements (HREEs). The daily mean and 95th percentile (P95) exposure to REEs from tea for the general population in China were 0.0328 µg/kg BW and 0.1283 µg/kg BW, respectively, which are significantly lower than the temporary acceptable daily dose (tADI). Our findings suggest that REEs from tea do not pose a known health risk to Chinese consumers.


Asunto(s)
Metales de Tierras Raras , , Té/química , Metales de Tierras Raras/análisis , China , Medición de Riesgo , Humanos , Contaminación de Alimentos/análisis , Exposición Dietética
2.
Artículo en Inglés | MEDLINE | ID: mdl-38805241

RESUMEN

This study presents a method based on acid transesterification and the purification by solid-phase extraction (SPE) coupled with gas chromatography-tandem mass spectrometry for quantifying 3- and 2-monochloropropanediol esters (3-MCPDE, 2-MCPDE) and glycidyl esters (GE) in nutritional foods. The fat was extracted by liquid-liquid extraction with petroleum ether and diethyl ether after the sample was hydrolysed with ammonia. Then the extract was purified by a SPE cartridge filled with the aminopropyl sorbents. It was demonstrated that the optimal elution volume for 3-MCPDE, 2-MCPDE and GE greatly depended on the sample matrix and varied from 6 to 12 mL for four different kinds of food matrices. All three analytes in the sample solution could be fully collected in the first 10-12 mL of eluate. By this way, monoacylglycerols commonly present in the samples were fully removed. Therefore, the overestimation of GE quantification was effectively eliminated. The modified analytical procedure was fully validated in a single laboratory and has been recommended as a Chinese Food Safety National Standard. In addition, two derivatisation agents, heptafluorobutyrylimidazole and phenylboronic acid, were proved to be equivalent in method accuracy and precision for the quantification of three analytes.


Asunto(s)
Ésteres , Análisis de los Alimentos , Contaminación de Alimentos , Cromatografía de Gases y Espectrometría de Masas , Propanoles , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Ésteres/análisis , Hidrólisis , Contaminación de Alimentos/análisis , Propanoles/análisis , Propanoles/química , Compuestos Epoxi/análisis , Compuestos Epoxi/química , alfa-Clorhidrina/análisis , Ácidos/análisis , Ácidos/química
3.
Foods ; 13(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38472866

RESUMEN

Nicarbazin (NICA) and triazine anticoccidial drugs (diclazuril (DIZ) and toltrazuril (TOZ)) are the primary strategy for preventing and treating coccidiosis. To prevent the development of drug resistance and mitigate the potential chronic toxicity to humans resulting from prolonged exposure, a liquid chromatography-tandem mass spectrometry method with high reliability and sensitivity was developed to determine NICA, DIZ, TOZ, and its two metabolites in chicken muscle and eggs. Upon establishing the extraction conditions involving 10 mL of acetonitrile and 10 min of sonication, in-syringe dispersive solid-phase extraction with silica was performed in combination with n-hexane clean-up. The selection of isotope peaks of precursor ions and low-mass range scanning allowed the two transitions for the quantification of all compounds. The limits of detection for DIZ and NICA were both 0.1 µg/kg, and for TOZ and metabolites, they were 0.3 µg/kg; the limits of quantitation were 0.3 and 1 µg/kg, respectively. The linear range was 0.25-50 ng/mL with a correlation coefficient r > 0.999. The average recoveries at three spiking levels in muscle and eggs were 90.1-105.2% and 94.0-103.7% with the relative standard deviations of 3.0-8.1% and 3.1-14.4%, respectively. The precision, accuracy, and stability were evaluated by three quality control samples.

4.
Antibiotics (Basel) ; 11(10)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36289951

RESUMEN

Antibiotics, especially fluoroquinolones, have been exhaustively used in animal husbandry. However, very limited information on the occurrence and exposure assessment of fluoroquinolone residues in chicken and pork in China is available to date. Thus, a total of 1754 chicken samples and 1712 pork samples were collected from 25 provinces in China and tested by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for residual determination of six common fluoroquinolones. The results revealed that the detection frequencies of fluoroquinolone residues were 3.99% and 1.69% in chicken and pork samples. The overall violation frequencies were 0.68% and 0.41% for chicken and pork. Enrofloxacin and its metabolite ciprofloxacin were found to be the most predominant fluoroquinolones. The occurrence of these antibiotics in different sampling regions and market types was analyzed. The %ADI values of enrofloxacin and ciprofloxacin were far less than 100, indicating the health risk associated with the exposure to these aforementioned fluoroquinolone residues via chicken and pork for Chinese children, adolescents, and adults was acceptable. The results provided useful references for Chinese consumers, and helped to appropriately use these antibiotics in poultry and livestock industry.

5.
Molecules ; 27(6)2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35335172

RESUMEN

The four polycyclic aromatic hydrocarbon markers (PAH4) of benzo[a]anthracene (BaA), chrysene (Chr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP) are indicators showing polycyclic aromatic hydrocarbon (PAH) contamination levels in Chinese medicine raw materials (CMRMs), extracts and health food products; Samples of herbal medicine, herbal extracts, and food supplements were extracted with n-hexane, then cleaned up sequentially on Florisil and EUPAH solid-phase extraction (SPE) columns. A gas chromatography-mass spectrometry method for the determination of four polycyclic aromatic hydrocarbon markers in Chinese medicine raw material, extracts, and health food products was established; In spiked-recovery experiments, the average recovery was about 78.6-107.6% with a precision of 2.3-10.5%. The limit of quantification (LOQ) and limit of detection (LOD) of the PAH4 markers in this method were 2.0 µg/kg and 0.7 µg/kg, respectively. When the developed method was utilized to determine PAH4 contents in 12 locally available health food products, 3 samples contained over 10.0 µg/kg BaP, and 5 samples contained over 50.0 µg/kg PAH4. The European Union (EU) limits for BaP and PAH4 are 10 and 50.0 µg/kg, respectively; therefore, more attention must be drawn to the exposure risk of BaP and PAH4 in CMRMs, their extracts, and health food products. According to the risk assessment based on the Margin of Exposure (MOE) method, it is recognized that the products mentioned in this study pose a low risk.


Asunto(s)
Alimentos Especializados , Hidrocarburos Policíclicos Aromáticos , Contaminación de Alimentos/análisis , Alimentos Especializados/análisis , Medicina Tradicional China , Extractos Vegetales , Hidrocarburos Policíclicos Aromáticos/análisis
6.
Artículo en Inglés | MEDLINE | ID: mdl-35286232

RESUMEN

The objective of this study was to investigate the potential effects from exposure to multiple metals, including cadmium (Cd), chromium (Cr), arsenic (As), mercury (Hg), nickel (Ni) and lead (Pb) that exist in shellfish in Chinese populations, and evaluate the impacts of cumulative exposures among individuals. A total 15,469 individual shellfish samples were analyzed following a protocol for elemental analysis. A total of 25,669 respondents were selected through stratified multi-stage cluster sampling from  31 survey sites in China. Individual shellfish consumption data and body weight were collected and analyzed with a 24-hour dietary recall method on three non-consecutive days. The consumers were divided into two groups: aged 2-12 years group and aged ≥13 years. Exposure levels were estimated based using a semi-probabilistic risk assessment method and cumulative exposures among individual persons using the maximum cumulative ratio (MCR) method. The mean, median and 95th percentile of all metals exposure for age 2-12 years group were higher than age ≥13 years group, but none exceeded the respective reference doses of the metals. The mean hazard indices (HI) of each metal in shellfish for both age groups were less than 1. The MCR values calculated among 1283 consumers ranged from 1.28 to 3.25 with the average MCR value was 2.22. There were 51 (3.98%) consumers in group I, 1186 (92.44%) consumers in group II, 26(2.03%) consumers in group III A, and 20 (1.56%) consumers in group III B. And cadmium (Cd) and lead (Pb) produced the HQMax that trigged cumulative exposures. It was concluded that heavy metals did not present a potential health risk to people solely through shellfish. The cumulative risks indicated that 7.56% of the surveyed consumers were of concern because of high HI of metals exposure, and Cd, Pb, and Ni made significant contributions to the potential risk.


Asunto(s)
Mercurio , Metales Pesados , Cadmio/análisis , Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Humanos , Plomo/análisis , Mercurio/análisis , Metales Pesados/análisis , Medición de Riesgo , Alimentos Marinos/análisis , Mariscos/análisis
7.
J Chromatogr Sci ; 61(1): 1-6, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35253058

RESUMEN

Croton fruit poisoning was successfully identified through a series of chromatographic technologies. A suspected compound named 2-methyl-butenoic acid was screened out using gas chromatography-mass spectrometry, and the hydrolysate of isoguanosine in soup sample was further detected by high performance liquid chromatography-tandem mass spectrometry. The identification of croton fruit poisoning was confirmed basing on these laboratory tests together with the clinical symptoms of the patients. Especially, the false-negative result and the interferences were successfully excluded through simulation test, spectral analysis and chromatographic separation technique. Such study is significant for croton poisoning identification and provides beneficial references for disposing untargeted food poisoning incident.


Asunto(s)
Croton , Espectrometría de Masas en Tándem , Humanos , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión , Frutas/química
8.
Artículo en Inglés | MEDLINE | ID: mdl-34506721

RESUMEN

The contents of perchlorate and chlorate were determined in a total of 278 samples of infant formulas marketed in China. The associated health risk via infant and young child formulas consumption for 0-36 month old children in China was also assessed. The contents of perchlorate and chlorate were measured by a validated method with LC-MS and the limit of detection (LOD) was 1.5 µg kg-1 and 3.0 µg kg-1 for perchlorate and chlorate, respectively. Perchlorate and chlorate were detected in about 85.8% (median 6.92 µg kg-1, maximum 74.20 µg kg-1) and 99.3% (median 52.80 µg kg-1, maximum 2780 µg/kg) of the samples. The exposures of infant and young children to perchlorate from formulas were lower than the provisional maximum tolerable daily intake (PMTDI, 0.7 µg/kg bw/day), which was established by U.S. Environmental Protection Agency (EPA). The European Food Safety Authority (EFSA) in 2015 also proposed a tolerable daily intake (TDI) of 3 µg/kg bw/day for chlorate based on the mean and average concentrations. Only for infants 0-6 month at the 95th percentile did exposures exceed the TDI of 3 µg/day for chlorate. Therefore, the safety of infant and young child formulas is excellent. To our knowledge, this is the first report to assess the exposure of infant and young child formulas in China to perchlorate and chlorate.


Asunto(s)
Cloratos/análisis , Exposición a Riesgos Ambientales/análisis , Análisis de los Alimentos , Contaminación de Alimentos/análisis , Fórmulas Infantiles/química , Percloratos/análisis , Preescolar , China , Cromatografía Liquida , Ingestión de Alimentos , Humanos , Lactante , Recién Nacido , Espectrometría de Masas , Nivel sin Efectos Adversos Observados
9.
Wei Sheng Yan Jiu ; 49(2): 238-241, 2020 Mar.
Artículo en Chino | MEDLINE | ID: mdl-32290939

RESUMEN

OBJECTIVE: To investigate the contamination levels of sodium nitrite in cooked meat from parts of China during 2012-2015. METHODS: The samples were detected in accordance with the national standardization method, and were determined by the GB 2760-2014. RESULTS: The average sodium nitrite in cooked meat was 9. 7 mg/kg with the content range from not detected to 85. 3 mg/kg, and its exceeding standard rate was 4. 8%(922/19360). The average sodium nitrite in visceral products was 16. 6 mg/kg, which was the highest in all kinds of cooked meat. The exceeding standard rate of farmers' market was significantly higher than that of other sampling links. The exceeding standard rate of bulk samples was 5. 8 times of the stereotyped packaging. The exceeding standard rate was downgrade year by year. The main problem was the bulk sauce-stewed meat product in the farm product market which the exceeding standard rate was 9. 5%(327/3461). CONCLUSION: A four-year successive observation shows that the quality of cooked meat with sodium nitrite is improved. But the problem is focused on the bulk. The risk of nitrite in cooked meat is lower.


Asunto(s)
Productos de la Carne/análisis , Nitrito de Sodio , China , Culinaria , Carne/análisis
10.
Environ Health Prev Med ; 23(1): 7, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29444637

RESUMEN

BACKGROUND: China has the world's largest tea plantation area in the world. To sustain high yields of the tea, multiple pesticides are used on tea crops to control pests. Organophosphorus (OP) pesticides are among the most widely used types of agricultural pesticides in China. As tea is a significant potential source of exposure to pesticide residues, the public concern has increased in relation to pesticide residues found in tea in China. The aim of the study was to estimate cumulative dietary exposure to OP residues from tea infusion for Chinese tea consumers to determine whether exposure to OP residues from tea infusion is a cause of health concern for tea consumers in China. METHODS: OP residue data were obtained from the China National Monitoring Program on Food Safety (2013-2014), encompassing 1687 tea samples from 12 provinces. Tea consumption data were obtained from the China National Nutrient and Health Survey (2002), comprising 506 tea consumers aged 15-82 years. The transfer rates of residues from tea leaves into tea infusions were obtained from the literature. The relative potency factor (RPF) approach was used to estimate acute cumulative exposure to 20 OP residues from tea infusion using methamidophos as the index compound. Dietary exposure was calculated in a probabilistic way. RESULTS: For tea consumers, the mean and the 99.9th percentile (P99.9) of cumulative dietary exposure to OP residues from tea infusion equalled 0.08 and 1.08 µg/kg bw/d. When compared with the acute reference dose (ARfD), 10 µg/kg bw/d for methamidophos, this accounts for 0.8 and 10.8% of the ARfD. CONCLUSIONS: Even when considering OP residues from vegetables, fruits and other foods, there are no health concerns based on acute dietary exposure to OP residues from tea infusion. However, it is necessary to strengthen the management of the OP pesticides used on tea in China to reduce the risk of chronic dietary exposure to OPs from tea infusion.


Asunto(s)
Exposición Dietética/análisis , Compuestos Organofosforados/análisis , Residuos de Plaguicidas/análisis , Té/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo/métodos , Adulto Joven
11.
PLoS One ; 12(5): e0177978, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28542445

RESUMEN

Cadmium, a toxic heavy metal, is widely present in food. It has been reported that chronic cadmium exposure is associated with kidney disease, osteoporosis, cardiovascular disease and cancer. The aim of this study was to assess the dietary cadmium exposure and potential health risk in different age-sex groups of the Chinese population (children aged 4-11 years, young people aged 12-17 years and adults aged over 18 years), and in the southern and northern population using a semi-probabilistic method. Cadmium was detected in 228,687 food samples from 32 food categrories by graphite furnace atomic absorption spectrometry. The dietary cadmium exposures were estimated by combining the cadmium concentration data with food consumption data derived from the China National Nutrient and Health Survey 2002, and evaluated against the Provisional Tolerable Monthly Intake (PTMI) of 25 µg/kg BW/month established by the Joint FAO/WHO expert committee on food additives (JECFA). The mean dietary cadmium exposure of the general Chinese population (15.3 µg/kg BW/month) was below the PTMI. The high consumer exposures (95th percentile, P95) for the general population and different sub-groups were higher than the PTMI. The dietary cadmium exposure of the southern population was apparently higher than that of the northern population. Rice was the most important contributor to cadmium exposure for Chinese people, especially those living in the southern areas of China. These findings indicated that the health risk from dietary cadmium exposure of the general Chinese people was low, but the health risk of cadmium exposure of certain sub-groups should be of concern.


Asunto(s)
Cadmio/análisis , Dieta , Contaminación de Alimentos/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Preescolar , China , Femenino , Contaminación de Alimentos/análisis , Humanos , Masculino , Persona de Mediana Edad , Espectrofotometría Atómica , Adulto Joven
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 49(3): 218-22, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26268864

RESUMEN

OBJECTIVE: To assess dietary exposure of diethylhexyl phthalate(DEHP) among Chinese population, including general population, children aged 2-6 years, adolescent aged 7-12, young people aged 13-17, adults aged 18-59 years old as well as older people aged 60 and above and its health risk. METHODS: A total of 6 650 food samples were collected during 2011 to 2013 from 140 local markets of 14 provinces in China, which covered major foods in China. Samples were detected by GC-MS and categorized into 22 food groups. Food consumption data were taken from China National Nutrition and Health Survey performed in 2002 including 68 959 subjects. Mean concentrations of DEHP in food were combined with individual food consumption data to estimate dietary exposure, and food contributors to dietary DEHP intake were also calculated. Then, the exposure was compared with the tolerable daily intake (TDI, 50 µg·kg(-1)-d(-1)) of DEHP. RESULTS: DEHP level in foods (n = 6 650) was in the range of not detected to 43.80 mg/kg. Mean dietary intakes of DEHP in general population was 2.07 (95% CI: 0.06-4.09) µg·kg(-1)·d(-1), accounting for 4.14 percent of TDI (50 µg·kg(-1)·d(-1)). Mean dietary intake for population aged 2-6, 7-12, 13-17, 18-59 as well as elderly aged 60 and above were 3.92 (95% CI: 0.83-7.01), 3.02 (95% CI: 0.69-5.36), 2.17 (95% CI: 0.54-3.81), 1.83 (95% CI: 0.46-3.21) and 1.66 (95% CI: 0.38-2.94) µg·kg(-1)·d(-1) respectively. The 97.5 percentile intakes in the general populations was 4.73 µg·kg(-1)·d(-1), accounting for 9.46% of TDI. Main food sources of DEHP were rice (28.4% (0.59/2.07)), melon solanaceous vegetables (14.7% (0.30/2.07)) and flour (13.2% (0.27/2.07)) for the general population. CONCLUSION: The results suggested that dietary exposure to DEHP among Chinese population was lower than tolerable daily intake of DEHP and there were no health concerns based on generally accepted exposure limits. Rice, melon solanaceous vegetables and flour were main food contributors of DEHP dietary intake for Chinese populations.


Asunto(s)
Encuestas sobre Dietas , Dietilhexil Ftalato , Harina , Contaminación de Alimentos , Oryza , Medición de Riesgo , Verduras , Adolescente , Adulto , Anciano , Pueblo Asiatico , Niño , Preescolar , China , Dieta , Alimentos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Persona de Mediana Edad
13.
J Sep Sci ; 38(4): 605-11, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25492053

RESUMEN

4,4'-Diaminostilbene-2,2'-disulfonic acid based fluorescent whitening agents (DSD-FWAs) are prohibited in food-contact paper and board in many countries. In this work, a reliable high-performance liquid chromatography method was developed for the simultaneous determination of 11 common DSD-FWAs in paper material. Sample preparation and extraction as well as chromatographic separation of multicomponent DSD-FWAs were successfully optimized. DSD-FWAs in prepared samples were ultrasonically extracted with acetonitrile/water/triethylamine (40:60:1, v/v/v), separated on the C(18) column with the mobile phase containing tetrabutylammonium bromide, and then detected by a fluorescence detector. The limits of detection were 0.12-0.24 mg/kg, and the calibration curves showed the linear correlation (R(2) ≥ 0.9994) within the range of 8.0-100 ng/mL, which was equivalent to the range of 0.80-10 mg/kg in the sample. The average recoveries and the RSDs were 81-106% and 2-9% at two fortification levels (1.0 and 5.0 mg/kg) in paper bowls, respectively. The successful determination of 11 DSD-FWAs in food-contact paper and board obtained from local markets indicated that the newly developed method was rapid, accurate, and highly selective.

14.
Int J Hyg Environ Health ; 217(6): 695-701, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24680371

RESUMEN

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. Food consumption data were taken from China National Nutrient and Health Survey which was performed in 2002 and includes data from 68,959 subjects. Mean concentrations of DEHP were combined with individual food consumption data to estimate dietary exposure. It was found that DEHP levels in foods ranged from not detected to 3.41 mg/kg, with highest mean values in meat (0.23 mg/kg) and vegetable oils (0.21 mg/kg). Mean dietary intakes of DEHP in the general population, children, and adults were 2.34, 4.51, 2.03 µg/kg bw per day, respectively. The 97.5% intakes in these populations were 5.22, 8.43, 3.64 µg/kg bw per day, respectively. The main food sources of DEHP dietary intake were cereals (39.44%), drinking water (16.94%) and meat (15.81%) in children, and cereals (44.57%), meat (15.70%) and drinking water (12.28%) for adults. These findings suggested that dietary exposure to DEHP among Chinese population was lower than tolerable daily intake of DEHP and there are no health concerns based on generally accepted exposure limits.


Asunto(s)
Dieta , Dietilhexil Ftalato/análisis , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Contaminación de Alimentos/análisis , Plastificantes/análisis , Adolescente , Adulto , Anciano , Niño , Preescolar , China , Humanos , Persona de Mediana Edad , Adulto Joven
15.
Wei Sheng Yan Jiu ; 42(5): 800-4, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24218888

RESUMEN

OBJECTIVE: To find out and compare the professionals proficiency of monitoring and inspection agencies on pesticide residue in food, and identify the main factors affecting the quality of result to provide references for improving the quality of the monitoring and inspection results. METHODS: Compare the national quality control examination results of pesticides residues in food of 2009 with 2011. RESULTS: The submission rates of examination results in 2011 were much higher than in 2009. They were respectively 100% and 83.6%. With the exception of few pesticides, the qualitative qualification rate and quantitative satisfaction rate of other pesticides were also relatively higher, and the qualitative qualification rate and quantitative satisfaction rate in 2011 were all higher than the same examination pesticides in 2009. For instance, the qualitative qualification rate of chlorpyrifos were respectively 99.4% and 96.8% in 2011 and 2009. The qualitative qualification rate of triazophos were respectively 100% and 97.1% in 2011 and 2009. The quantitative satisfaction rate of chlorpyrifos were respectively 93.8% and 90.2% in 2011 and 2009. The quantitative satisfaction rate of triazophos were respectively 91.9% and 87.2% in 2011 and 2009. CONCLUSION: The general testing levels of monitoring and inspection agencies on pesticide residue in food were sufficient, and their testing proficiency increased year by year, but some institutions still need to improve the testing proficiency.


Asunto(s)
Análisis de los Alimentos/normas , Contaminación de Alimentos/estadística & datos numéricos , Residuos de Plaguicidas/análisis , China , Contaminación de Alimentos/análisis , Humanos , Control de Calidad , Medición de Riesgo
16.
PLoS One ; 8(7): e68186, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23874534

RESUMEN

Three Gorges Reservoir (TGR) is one of the largest man-made lakes in the world. Since the impoundment in 2003, however, algal blooms have been often observed in the tributary embayments. To control the algal blooms, a thorough understanding of the hydrodynamics (e.g., flow regime, velocity gradient, and velocity magnitude and direction) in the tributary embayments is particularly important. Using a calibrated three-dimensional hydrodynamic model, we carried out a hydrodynamic analysis of a typical tributary embayment (i.e., Xiangxi Bay) with emphasis on the longitudinal patterns. The results show distinct longitudinal gradients of hydrodynamics in the study area, which can be generally characterized as four zones: riverine, intermediate, lacustrine, and mainstream influenced zones. Compared with the typical longitudinal zonation for a pure reservoir, there is an additional mainstream influenced zone near the mouth due to the strong effects of TGR mainstream. The blooms are prone to occur in the intermediate and lacustrine zones; however, the hydrodynamic conditions of riverine and mainstream influence zones are not propitious for the formation of algal blooms. This finding helps to diagnose the sensitive areas for algal bloom occurrence.


Asunto(s)
Eutrofización , Lagos , Monitoreo del Ambiente , Hidrodinámica , Modelos Teóricos
17.
Wei Sheng Yan Jiu ; 41(3): 467-70, 475, 2012 May.
Artículo en Chino | MEDLINE | ID: mdl-23050451

RESUMEN

OBJECTIVE: To establish a determination method for aspartame and alitame in jellies and preserved fruits. METHODS: Aspartame and alitame in jellies were extracted with 80% methanol at 70 degrees C. Preserved fruits were homogenized with water and then were extracted with 50% methanol. A chromatographic column Zorbax SB-C18 was used; the mobile phase was methanol/water (40 + 60, volume ratio), and a diode array detector was used for the detection at wavelength 200 nm. RESULTS: The limits of quantification of aspartame and alitame were both 8 mg/kg for jellies and both 20 mg/kg for preserved fruits; the calibration curves were linear in the range of tested concentration. The correlation coefficients were better than 0.9996. The average recovery rates were in the range of 98.1% -101.2%, the relative standard deviations were 2.21% - 4.10%. CONCLUSION: The method is simple, practical, accurate, reliable and successful in the determination of aspartame and alitame in jellies and preserved fruits from various brands on markets.


Asunto(s)
Aspartame/análisis , Dipéptidos/análisis , Frutas/química , Cromatografía Líquida de Alta Presión , Alimentos en Conserva
18.
Wei Sheng Yan Jiu ; 41(2): 204-8, 2012 Mar.
Artículo en Chino | MEDLINE | ID: mdl-22611926

RESUMEN

OBJECTIVE: To know about food safety situation and provide scientific data for the development of food safety policies and laws. METHOD: Monitoring task was carried out in some areas of China by some measures and steps such as formulating plan, compiling SOP, holding technical training, having quality controls, data collection, checking and statistics of food chemical contaminant monitoring. RESULTS: 14 categories of foods and 129 chemicals were cumulatively surveyed in 16 provincial areas for ten years. A database with more than 1.05 million monitoring data was established. Monitoring results showed that food safety situation in China was generally stable and gradually good, but also problems of some food safety were found. Monitoring data had been used for alerts, supervision, risk assessment and standard setting of food safety. CONCLUSION: The monitoring for 10 years knew about the contamination levels and dynamic trend of contaminants in food, provided scientific data for the development of food safety policies and laws, and laid the foundation for national food contamination monitoring.


Asunto(s)
Aditivos Alimentarios/análisis , Análisis de los Alimentos/estadística & datos numéricos , Contaminación de Alimentos/análisis , Residuos de Plaguicidas/análisis , China , Inocuidad de los Alimentos , Humanos , Micotoxinas/análisis
19.
Biomed Environ Sci ; 22(2): 104-8, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19618686

RESUMEN

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. The HPLC method was used to detect melamine. RESULTS: No melamine was detected in 15 dairy product containers. Among the 22 plastic samples, 16 of polypropylene, and polycarbonate types had no detectable amount melamine while a low level of melamine was found in 3 of the 6 melamine resin containers. CONCLUSION: Migration of melamine from food packaging materials in China market is in line with the requirements of EU.


Asunto(s)
Embalaje de Alimentos , Triazinas/química , Animales , Bovinos , China , Productos Lácteos , Difusión , Análisis de los Alimentos , Contaminación de Alimentos , Leche , Plásticos/química , Espectrofotometría Ultravioleta
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 42(5): 304-6, 2008 May.
Artículo en Chino | MEDLINE | ID: mdl-18844076

RESUMEN

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. RESULTS: All 1358 data on contents of lead in the preserved eggs were obtained during seven years, the total average was 1.782 mg/kg, the maximum was 334.0 mg/kg, P90 was 3.50 mg/kg, P95 was 7.397 mg/kg and P97.5 was 12.01 mg/kg, all exceeded 2 mg/kg of the national limit standard, and the rate of violated samples exceeded 10.0%. Analyzing from time, contents of lead in the preserved eggs were depressive from 2.994 mg/kg to 1.138 mg/kg year after year. CONCLUSION: The lead contamination in preserved eggs was serious in whole country. It shows that the continuous work of monitoring and forewarning should be carried out to make the contamination of lead in preserved eggs to reduce year by year.


Asunto(s)
Huevos/análisis , Contaminación de Alimentos/análisis , Plomo/análisis , China , Manipulación de Alimentos/métodos , Inspección de Alimentos/métodos
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