Determination of Polycyclic Aromatic Hydrocarbons in Traditional Chinese Medicine Raw Material, Extracts, and Health Food Products.

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.

[Sodium nitrite in cooked meat during 2012-2015 in China].

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.

Estimated assessment of cumulative dietary exposure to organophosphorus residues from tea infusion in China.

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.

Simultaneous determination of 11 fluorescent whitening agents in food-contact paper and board by ion-pairing high-performance liquid chromatography with fluorescence detection.

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.

[Dietary intake and risk assessment of diethylhexyl phthalate in Chinese populations].

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.

Simultaneous Analysis of Nicarbazin, Diclazuril, Toltrazuril, and Its Two Metabolites in Chicken Muscle and Eggs by In-Syringe Dispersive Solid-Phase Filter Clean-Up Followed by Liquid Chromatography-Tandem Mass Spectrometry.

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.

Determination of chloropropanol esters and glycidyl esters in nutritional foods by gas chromatography-tandem mass spectrometry based on acid hydrolysis and solid-phase extraction.

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.

Concentration and health risk assessment of 16 rare earth elements in six types of tea in China.

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.

[Comparison and anylisis on national quality control examination results of pesticides residues in food in 2009 and 2011].

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.

[Simultaneous determination of aspartame and alitame in jellies and preserved fruits by HPLC].

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.

[Overview and analysis of food chemical contaminant monitoring in 2000-2009 in China].

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.

Occurrence and Risk Assessment of Fluoroquinolone Residues in Chicken and Pork in China.

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.

Screening and Identification of Croton Fruit Poisoning in Food Using GC-MS and HPLC-MS/MS.

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.

Application of the maximum cumulative ratio (MCR) as a screening tool for the evaluation of multiple metal mixtures in shellfish in Chinese population.

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.

The contamination and estimation of dietary intake for perchlorate and chlorate in infant formulas in China.

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.

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. 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.

[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. 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.

Dietary cadmium exposure assessment among the Chinese population.

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.

[Survey on the cadmium levels in fish, crustaceans and bivalve mollusks in China of 2002].

A survey on the cadmium content of fresh water, marine fish bivalve mollusks and crustaceans in China was carried out by the National Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention in 2002. The fish from fresh water (n = 193), marine (n = 367), crustaceans (n = 318) and bivalve mollusks (n = 512) were collected from 14 provinces and cities and analyzed by AAS. It was found that the samples with mean concentration between 0.06-0.53 mg/kg. However, some of samples were up to 8 mg/kg, indicating that the cadmium content of some fishes exceeded the maximum level of national standards.

[Study on the determination of chloramphenicol residues in muscles and viscera of the livestock and poultry and in the shrimp].

OBJECTIVE: A rapid, simple and sensitive high performance liquid chromatographic method for the determination of chloramphenicol residues in muscles and viscera of the livestock and poultry and in the shrimp has been established. METHODS: The chloramphenicol in animal tissues is extracted three times by ethyl acetate in ultrasonic. The extract is dehydrated with Na2SO4 and concentrated. The residues are cleaned up by 0.5 mol/L HClO4 and n-hexane. The purified solution is detected at UV 278 nm by HPLC. RESULTS: The detection limit of this method is 1.6 micrograms/kg in muscles and 3.2 micrograms/kg in viscera, the recovery is from 82.1% to 96.6%, RSD is 5.3%-6.4%. CONCLUSION: This method can be widely applied to animal-foods, and its recovery is high, and its detection limit is low, and it is easily popularized in countryside.