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81.
This study was designed to investigate how and to what extent PCDD/Fs and PCBs are transmitted from exposure sources to porcine muscle and other tissues derived from pigs. The experimental approach involved two longitudinal studies in which indoor and outdoor pigs were reared to market readiness using typical animal husbandry practices; closely matched samples of soil, feed, bedding, meat, etc. were collected and analysed for PCDD/Fs and PCBs. The total PCDD/F?+?PCB WHO-TEQs in pig liver were much higher than in meat and kidney samples from the same animals and exceeded the current relevant European Union maximum limits (6?ng PCDD/F-TEQ?kg?1?fat). Liver samples were also characterised by much lower PCB contributions to the total TEQ than for the corresponding meat and kidney samples, and by a predominance of many of the hepta- and octa-substituted PCDD/Fs. At ages approaching market readiness, TEQ values in meat samples from outdoor pigs tended to be slightly higher than those from comparable ages in the indoor programme, possibly due to additional intake from soil. Biotransfer factors (BTFs) were derived for each of the 39 PCDD/F and PCB congeners measured. Interpretation of the findings focused particularly on trends in four selected congeners, namely: 2,3,7,8-TCDD, 2,3,4,7,8-PeCDF, PCB 153 and PCB 169. Increases in the BTF for PCB 169 in the pig-rearing programmes were noticed when the diet changed from being dominated by sow's milk to feed. Much higher transfer factors for many of the more heavily chlorinated PCDD/Fs (e.g. 2,3,4,7,8-PeCDF) were found in liver compared with meat or kidney samples from the same animals. Soil consistently accounted for at least 30% of input for many hexa- or higher chlorinated PCDD/Fs, while it rarely representing more than 10% of the total intake.  相似文献   
82.
The European Union approach to assessing exposure to chemical migrants from plastic food-contact materials has been to assume an intake of 1 kg of food in contact with a particular material, per 60 kg person per day, which equates to 16.7 g kg?1 body weight. A food packaging surface area–food mass ratio of 6 dm2/1 kg is assumed, equivalent to 0.1 dm2 kg?1 of body weight. Children might be at increased risk to exposure from migrants as they have higher intakes of food per kg body weight compared with adults. In addition, much of the food marketed for/to children is in small portions and therefore the food-contact material area–food mass ratio is relatively high. To determine if, and how, the European Union model might be modified to ensure specific protection against chemical migration into food marketed for children, data on 4-day food intakes of 297 children aged 0–6 years were collected including information on pack size, pack type and food-contact material area–food mass ratio. The 297 children consumed a total of 1646 kg of food and drink (including tap water), of which 978 kg (59%) was packaged with 67% of this packaged in plastics. Mean intakes of food packaged in plastic ranged from 27 g kg?1 body weight (for the infants under 1 year) to 51 g kg?1 body weight (for the 1–4-year-olds). This was higher than the 16.7 g kg?1 body weight derived from the European Union convention. The mean area of packaging in contact with the food consumed daily per kg body weight were 0.65 dm2 kg?1 for the infants under 1 year, 0.81 dm2 kg?1 for the 1–4-year-olds, and 0.66 dm2 kg?1 for the 4–6-year-olds. All 297 children had intakes that exceeded 0.1 dm2 of packaging per kg of body weight assumption.  相似文献   
83.
A survey was conducted to determine the occurrence of fumonisin B1, B2 and B3 during 2007 in 186 samples of organic and conventional locally available corn products. Samples included baby food (n = 62), corn flour (11), cornflakes (23), pasta (14), cookies (17) and other corn products (59) were obtained from popular markets of Valencia (Spain) and Perugia (Italy). The analytical method used pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyser. Of the 104 Spanish samples, 22% contained levels in the range of 2–449 µg kg?1, 2–229 µg kg?1 and 6–105 µg kg?1 for FB1, FB2 and FB3, respectively, while 19 (23%) of the 82 Italian samples were positive with quantifiable levels between 2–235 µg kg?1, 3–187 µg kg?1, and 4–40 µg kg?1 for fumonisins B1, B2 and B3, respectively. Overall, none of the Italian samples and only one organic baby food sample from a Spanish market was above the maximum permitted levels established by European legislation. Fumonisins were found mostly in corn flour followed by cookies and cornflakes. Eleven samples from Spain and nine samples from Italy were organic products, being contaminated the 72% and 77% of the samples, respectively. Analysis of the results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of fumonisin intake through corn products was demonstrated by the calculation of the estimated daily intake of both populations considering organic and conventional products separately, which ranged from 1.7 × 10?3 to 0.72 µg kg?1 bw day?1 and comparing them with the provisional maximum total daily intake (PMTDI) of 2 µg kg?1 bw day?1 established by the European Union.  相似文献   
84.
ABSTRACT

The aim of the study was to assess the dietary intake of caramel colours and their by-products 4-methylimidazole (4-MEI) and 2-acetyl-4-tetrahydroxybutylimidazole (THI) for the Chinese population. Based on the typical and maximum reported use levels of caramel colours in 15 food categories, the dietary intakes of combined and single-class caramel colours of Classes I, III and IV were estimated with the food consumption data from the China National Nutrient and Health Survey. Using the mean values of 4-MEI and THI contents in Class III and Class IV Caramel colour samples, the exposures to 4-MEI and THI from dietary caramel colours were derived. The results showed that the combined and individual average dietary caramel colour intakes for the Chinese population of different age groups were estimated to be 232–60.3 mg kg?1 bw day?1 for combined caramels, 5.9–29.2 mg kg?1 bw day?1 for Class I, 7.7–29.6 mg kg?1 bw day?1 for Class III, 21.2–54.3 mg kg?1 bw day?1 for Class IV, which were far below the group acceptable daily intake (ADI) and respective ADIs. The combined intake of 4-MEI from Class III and IV caramel colours was estimated to be 3.8–5.2 μg kg?1 bw day?1 on average, and 12.9–27.1 μg kg?1 bw day?1 at 95th-97.5th percentile for the general population. The anticipated exposure to THI from Class III caramel colours was estimated to be 0.1–0.3 μg kg?1 bw day?1 on average and 0.5–1.7 μg kg?1 bw day?1 at 95th–97.5th percentile for the general population. The dietary caramel colours intakes and the exposures to 4-MEI and THI from dietary caramel colour for the Chinese population were considered to be of low health concern based on the present toxicological data. Soy sauce, vinegar and compound seasonings were found to be the main contributors to the dietary intake of caramel colours.  相似文献   
85.
ABSTRACT

The aim of this study was to determine levels of 11 mycotoxins, 10 trace elements, and 6 phthalates in rice samples from Serbian and Chinese market. Mycotoxins were not detected in any of the analysed rice samples. Results revealed similar median levels for following elements: Mn, 17.5 and 15.7 mg kg?1; Fe, 2.47 and 2.12 mg kg?1; Cu, 1.95 and 1.59 mg kg?1 in marketed samples from Serbia and China, respectively. Median concentration of Ni in Serbian marketed samples was 1.9 times higher than in Chinese ones. The median levels (µg kg?1) of phthalates ranged from 1.2 (benzylbutyl phthalate [BBP]) – 566 (di(2-ethyl-hexyl) phthalate [DEHP]) and 1.7 (BBP) – 348 (DEHP) in Serbian and Chinese marketed samples, respectively. The results were used to assess daily exposure of Serbian and Chinese adult consumers. The calculated target hazard quotients indicated that the potential risk attributable to the analysed contaminants in rice samples should not be of concern neither for the Serbian nor the Chinese consumers.  相似文献   
86.
ABSTRACT

A total of 576 samples marketed in China, including maize, maize flour, maize grits and maize meal, was determined for the simultaneous presence of 12 mycotoxins (FB1, FB2, FB3, DON, 3-DON, 15-DON, ZEN, AFB1, AFB2, AFG1, AFG2 and OTA) using a validated UPLC-MS/MS for multi-mycotoxin method. DON were the most widespread mycotoxins (63%), followed by FB1 (57%) and ZEN (46%). 78% of the samples was contaminated with at least one of these mycotoxins. Risk assessment indicated that maize and maize-derived food intake does not pose a potential risk for general adult population with respect to individual mycotoxin. However, two or more mycotoxins were detected in 60% of all samples, and a combination of up to seven different mycotoxins was found. A particular attention should be paid to the combined exposure of mycotoxins, in this cases the estimated daily intake might increase greatly due to the high frequency of co-occurrence.  相似文献   
87.
88.
The content of nitrate in leafy vegetables, culinary herbs, and cucumber was determined during the years 2006–2008. All samples of Estonian origin, except white cabbage, were grown under cover. Seasonal differences in nitrate concentrations were observed in lettuce and spinach. Nitrate concentrations in lettuce were 22% and those in spinach were 24% higher in winter crops compared with samples collected in summer. The mean nitrate level was 3023 mg kg–1 for fresh lettuce and 2337 mg kg–1 for spinach. On average, 11.6% of fresh lettuce and spinach samples nitrate concentration exceeded the maximum level specified in European Commission Regulation No. 1881/2006. The mean levels were 999 mg kg–1 for imported iceberg lettuce and 1287 mg kg–1 for frozen spinach, which are below the maximum European Commission limits. Parsley, dill, basil, thyme, and rucola contained high concentrations of nitrate from mean levels of 2134 mg kg–1 for parsley up to 8150 mg kg–1 for rucola. Mean nitrate concentrations ranged from 382 to 1115 mg kg–1 for white cabbage and Chinese cabbage, respectively. The per capita mean daily intake of nitrates related to the consumption of leafy vegetables, culinary herbs, and cucumber for the whole Estonian population was 31.3 mg day–1, which comprised 14.2% of the acceptable daily intake (ADI).  相似文献   
89.
The aim of this study was to estimate the dietary intake of arsenic (As) by children and adults from Jinhu area of China. A duplicate diet approach was used to collect diet samples in November and December 2007. The As content was measured by hydride generation atomic fluorescence spectrometry. The As intakes (median) for different group were: children: 0.6 µg kg?1 bw day?1 or 6.7 µg kg?1 bw week?1; adults: 0.5 µg kg ?1 bw day?1 or 3.8 µg kg ?1 bw week?1, none of which exceeded the provisional tolerable weekly intake (PTWI) of 15 µg kg ?1 bw week?1 for As proposed by the World Health Organization (WHO). The median and maximum of the children group amounted to 44.7% and 125.3% of the PTWI; the values for adults were 25.3% and 118.7%, respectively. There were 3.3% of children whose weekly As intake exceeded the PTWI, and there were 6.7% of adults whose weekly As intake exceeded the PTWI. It is concluded that dietary As intake was safe for most people in Jinhu area, but the high dietary As intake for a minority of people in this area deserves attention.  相似文献   
90.
A study was undertaken to determine levels of aflatoxins in rice. A total of 261 rice samples were analyzed by HPLC using a method was based on the extraction of 50?g of finely ground rice plus 5?g?NaCl with 200?ml of 80% methanol. After filtration and immunoaffinity clean-up, 20?µl was injected onto the HPLC. HPLC analysis was carried out using a Genesis RP C18 column (250?×?4.6, 4?µm I.D.) and a mobile phase with a linear gradient of water/methanol/acetonitrile (6?:?2?:?2?v/v) over 16?min. Aflatoxins were determined after post-column derivatisation with iodine by fluorescence detection at excitation and emission wavelengths of 365 and 445?nm, respectively. It was found that 68.9% of the rice samples contained aflatoxin B1 at levels greater than 0.2?ng?g?1.  相似文献   
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