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1.
Atomic fluorescence spectrophotometry was used to determine the selenium (Se) concentration in 30 rice products of different species from Southern China. The Se level ranged from 0.015 to 0.046 µg g?1. Considering the average daily individual consumption of rice products in Southern China, the average dietary intake of Se supplied by this source is only 6–18 µg day?1 for an adult. This low Se intake from rice products is mainly responsible for the low total Se intake of inhabitants in Southern China. Foliar spraying of Se‐enriched fertiliser or sodium selenite with 14–18 g Se ha?1 in the heading stage of rice growth increased the Se content to 0.178–0.421 µg g?1 in rice products. The concentration and amount of Se‐enriched fertiliser can be varied to achieve an optimum concentration of Se in rice products. The authors suggest that these Se‐enriched rice products can contribute an increase in Se intake of 50–100 µg day?1 on average if their Se concentration is controlled in the region of 0.15–0.50 µg g?1. © 2002 Society of Chemical Industry  相似文献   

2.
The total selenium content of about 800 food products purchased in Belgium was determined and combined with food records to determine the nutritional selenium status of Belgian people. The largest selenium concentrations (>1?mg?kg?1) were found in Brazil nuts and offal, of which the consumption is limited. Usually consumed food groups with the highest selenium concentrations were fish and shellfish (0.2–0.9?mg?kg?1), eggs, poultry meat, cheese, mushrooms and pasta (approximately 0.2?mg?kg?1). The mean dietary selenium intake was calculated to be 60?µg?day?1, which is at the lower end but within the range recommended by the Superior Health Council in Belgium (60–70?µg?day?1), and adequate according to the 55?µg?day?1 recommended by the Scientific Committee on Food (SCF) of the European Commission. The major sources of selenium intake are meat and meat products (31%), fish and shellfish (20%), pasta and rice (12%), and bread and breakfast cereals (11%).  相似文献   

3.
BACKGROUND: The aim of this study was to evaluate the intake of selenium, total and inorganic arsenic and the bioaccessibility of arsenic in diets of Mexican schoolchildren using an in vitro method. RESULTS: Total and inorganic arsenic concentrations in the diets ranged from 0.05 to 1.15 mg kg?1 dry weight (DW) and from 0.023 to 0.088 mg kg?1 DW respectively, while selenium levels were between 0.08 and 0.20 mg kg?1 DW. Daily intake of total and inorganic arsenic ranged from 0.15 to 10.49 µg day?1 kg?1 body weight (BW) and from 0.06 to 1.11 µg day?1 kg?1 BW respectively, while that of selenium varied from 0.29 to 2.63 µg day?1 kg?1 BW. Bioaccessibility of total and inorganic arsenic ranged from 4 to 97% (mean 44 ± 21.5%) and from 33 to 97% (mean 71 ± 22.5%) respectively. CONCLUSION: Inorganic arsenic levels in the diets were low. Therefore there appears to be a low risk of adverse effects resulting from excess inorganic arsenic intake from these diets. Copyright © 2011 Society of Chemical Industry  相似文献   

4.
The selenium concentration of representative bread‐making wheat (Triticum aestivum L) samples was measured in national grain surveys collected in 1982 (n (number of samples) = 180), 1992 (n = 187) and 1998 (n = 85) from major wheat‐growing regions around the UK. The means and distributions of selenium concentrations over the three years were similar, with mean grain concentrations of 0.025, 0.033 and 0.025 mg kg?1 dry weight respectively and inter‐quartile ranges varying from 0.015 mg kg?1 in 1982 to 0.019 mg kg?1 in 1992 samples. No long‐term changes in the distribution of wheat selenium concentrations were found over the 17 year period. Geographical mapping of the concentrations identified an area of eastern England as having high grain concentrations compared with other UK regions. There were no significant correlations between grain selenium and grain sulphur concentrations for the national survey samples. However, at an individual field experimental site, increasing the rate of sulphur addition was found to decrease grain selenium concentration significantly. The daily UK dietary contribution of selenium from wheat‐based products was estimated and the daily intake was calculated to be 6.4 µg selenium, around one‐tenth of the UK recommended intake values for men and women. © 2002 Society of Chemical Industry  相似文献   

5.
The selenium concentration in foods was analysed in order to identify principal sources of this trace element in Switzerland. Selenium intake estimations based on three different approaches were carried out. From the relationship between intake and serum/plasma concentration, the selenium intake was estimated to 66 µg day?1. The second approach based on measured food groups combined with consumption statistics; and the third approach consisted of duplicate meal samples. With the last two methods, over 75% of the serum/plasma based intake was confirmed. Swiss pasta made of North American durum wheat was the food with the highest contribution to the dietary intake, followed by meat. The strong decrease in imports of selenium-rich North American wheat of the last years was not reflected in the present intake estimations. It appears that this intake loss was compensated by a consumption increase of other foods. Compared with former intake estimations, selenium intake seems to be in Switzerland nearly constant for the last 25 years.  相似文献   

6.
Arsenic contamination of rice plants by arsenic-polluted irrigation groundwater could result in high arsenic concentrations in cooked rice. The main objective of the study was to estimate the total and inorganic arsenic intakes in a rural population of West Bengal, India, through both drinking water and cooked rice. Simulated cooking of rice with different levels of arsenic species in the cooking water was carried out. The presence of arsenic in the cooking water was provided by four arsenic species (arsenite, arsenate, methylarsonate or dimethylarsinate) and at three total arsenic concentrations (50,?250 or 500?µg?l?1). The results show that the arsenic concentration in cooked rice is always higher than that in raw rice and range from 227 to 1642?µg?kg?1. The cooking process did not change the arsenic speciation in rice. Cooked rice contributed a mean of 41% to the daily intake of inorganic arsenic. The daily inorganic arsenic intakes for water plus rice were 229, 1024 and 2000?µg?day?1 for initial arsenic concentrations in the cooking water of 50, 250 and 500?µg?arsenic?l?1, respectively, compared with the tolerable daily intake which is 150?µg?day?1.  相似文献   

7.
Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part of regulatory processes. The assessment of exposure to mercury shown in this paper has been performed by means of a study on the whole diet. Total mercury (Hg) levels were determined by cold vapour atomic absorption spectrometry (AAS) in 420 samples of regularly consumed food and drink. The total Hg concentrations measured in the different groups of food ranged from non-detectable to 119 µg kg?1 w/w. The fish group had the highest concentrations of total Hg. All groups of food with regulated Hg content showed levels that were lower than the legally set values. The food consumption data used in the analysis were taken from the latest nutritional survey made in the Canary Islands, Spain. The estimated total Hg intake of local population (5.7 µg/person day?1) did not exceed the provisional tolerable weekly intake (PTWI) limit of 0.3 mg week?1 of total mercury (43 µg/person day?1) fixed by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives. Fishery products contributed 96% of the total Hg intake. The mean Hg intake for each island in this archipelago, formed by seven, has also been calculated. Fuerteventura, Lanzarote and El Hierro are the islands with the highest level of Hg intake (7.0, 7,0 and 6.1 µg/person day?1, respectively). La Palma Island, due to its low fish consumption, had the lowest level of Hg intake (4.5 µg/person day?1), followed by La Gomera (5.4 µg/person day?1), Tenerife (5.5 µg/person day?1) and Gran Canaria (5.6 µg/person day?1). A comparison has been made of the results obtained in this study with those found for other national and international communities.  相似文献   

8.
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   

9.
This paper reports an estimate of the dietary intake of lead by children and adults from the Jinhu area in South-eastern China. A duplicate diet approach was used to collect food samples in November and December 2007. The lead content was measured by furnace atomic absorption spectrometry. Median lead intakes for different groups were as follows: children: 1.65 µg(kgbw)?1 day?1; and adults: 1.10 µg(kgbw)?1 day?1. No exposure exceeded the provisional tolerable weekly intake (PTWI) of 25 µg(kgbw)?1 week?1 proposed by the World Health Organization (WHO). However, median and maximum exposure for the children group amounted to 60.8% and 97.2% of the PTWI, respectively, which were higher than those for adults, which were 40.5% and 86.4%, respectively. It was concluded that health risks due to dietary lead intake seem to be high in Jinhu.  相似文献   

10.
This paper reports levels of 3-monochloropropan-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) in a wide range of food items and estimates their dietary exposure for secondary school students in Hong Kong. Dietary exposure to chloropropanols was estimated using local food consumption data obtained from secondary school students in 2000 and the concentrations of 3-MCPD and 1,3-DCP in food samples taken from the local market. The dietary exposure to 3-MCPD for an average secondary school student consumer was estimated to be 0.063–0.150 µg kg?1 body weight (bw) day?1, whilst that for the high consumer was 0.152–0.300 µg kg?1 bw day?1. Both estimates fell below the provisional maximum tolerable daily intake of 2 µg kg?1 bw established by the Joint Expert Committee on Food Additives (JECFA) and amounted to less than 20% of this safety reference value. The dietary exposure to 1,3-DCP for an average secondary school student consumer was estimated to be 0.003–0.019 µg kg?1 bw day?1, whilst that for the high consumer was 0.009–0.040 µg kg?1 bw day?1. The resulting margins of exposures were of low concern for human health. It could be concluded that both the average and high secondary school student consumers were unlikely to experience major toxicological effects of 3-MCPD and 1,3-DCP.  相似文献   

11.
The aim of this study was to investigate the presence of tetracycline residues in pasteurised cow’s milk using high-performance liquid chromatography coupled with UV/VIS detection to determine the exposure of Brazilian’s population to antibiotic residues. One hundred samples collected from the State of Paraná, Brazil, were analysed. Three of these samples were contaminated at the following concentrations: 121.8 µg·kg?1 for oxytetracycline, 93.5 µg·kg?1 for tetracycline and 134.6 µg·kg?1 for chlortetracycline (61.6 µg·kg?1) and doxycycline (73.0 µg·kg?1). The median tetracycline residue concentration found in the samples was 42.3 µg·kg?1, and the estimated daily intake (EDI) was 0.05 µg Kg?1 bw day?1 in Brazil. These results demonstrate that the occurrence of tetracycline in Brazilian milk was low (3%) and only for 2% above the maximum residue limit, so the risk to the population from the presence of these residues in milk was low (<1% of the acceptable daily intake).  相似文献   

12.
Potato crisps are one of the food commodities that contribute most to overall dietary human exposure of acrylamide. This investigation has estimated the dietary exposure to acrylamide form potato crisps in the Spanish population. Sampling of potato crisps (n = 36) from 16 different producers were carried out in March 2008. An average level of 740 µg kg?1 (ranging from 81 to 2622 µg kg?1; minimum to maximum) and a median of 592 µg kg?1 were obtained. Acrylamide levels in marketed potato crisps have been significantly reduced (nearly to 50%) compared with a previous sampling performed 4 years earlier. The observed signal value (90th percentile) was 1377 µg kg?1 with 86% of the samples with acrylamide levels lower than 1000 µg kg?1. Dietary exposure to acrylamide from potato crisp consumption in the total Spanish population was estimated to be 0.042 µg kg?1 body weight day?1 by using a deterministic approach based on the National consumption database. In a second study, dietary exposure (based on a 3-day food record) was determined to be 0.053 µg kg?1 body weight day?1 for the adult population (17–60 years) and 0.142 µg kg?1 body weight day?1 for children (7–12 years). The contribution of potato crisps to the estimated dietary acrylamide exposure of the Spanish population is moderate as compared with other European Member States.  相似文献   

13.
In order to assess aluminium intake via drinking water by children, approximately 400 households in urban, peripheral, and rural areas were investigated. The study comprised about 200 children (5–7 years old) in the period between 2000 and 2001. The samples of drinking water were collected by a double sampling method (morning and evening). Aluminium was measured by graphite furnace-atomic absorption spectroscopy (GF-AAS). Geometric means (µg l?1, confidence interval) were for evening samples: urban 72.5 (13.2–398), peripheral 6.3 (0.5–86.7), and rural 16.6 (0.5–593). For most households the aluminium concentration in the morning samples was lowered by about 40% due to deposition of aluminium-containing compounds during standing overnight. These deposits can be later taken up into the water. The European Commission aluminium limit of 200 µg l?1 for drinking water was exceeded for 7.7, 0 and 13.2% of households from urban, peripheral, and rural areas, respectively. The predicted contribution of drinking water to aluminium intake by 6-year-old children was 3.81 µg day?1 kg body weight?1 or 2.7% of the provisional tolerable weakly intake (PTWI. 1 mg kg?1 body weight) for urban sites and less for the others. For those cases exceeding the aluminium limit, the predicted aluminium intake via water consumption was 18.4–42.1 µg day?1 kg body weight?1 and contributed 12.8–29.5% of the provisional tolerable weakly intake. In urban areas the aluminium concentration was enhanced due to water treatment; while in rural sites it was due to contamination from cement-made wells. The high prevalence of cement wells in rural areas suggests that drinking water from individual sources should be included in a safety control system. The quality of materials for the construction of wells and containers for drinking water storage should be also improved. In order to limit aluminium intake from drinking water, this study also supports the suggestion of discarding overnight standing water before it is taken for consumption, especially for use by children.  相似文献   

14.
The occurrence of deoxynivalenol (DON) was investigated in 514 cereal-based products (corn-based, n = 125; barley-based, n = 96; wheat-based, n = 94; rice-based, n = 199) marketed in Korea during 2007?2008, and estimates of DON intake were determined. Samples were analysed by high-performance liquid chromatography (HPLC) with ultraviolet light (UV) detection after immunoaffinity clean-up. The limits of detection (LOD) and limits of quantification (LOQ) were 2.2 and 5.6 µg kg–1, respectively. Recoveries and repeatability expressed as coefficients of variation (CV) were 82.3–100% and 2.4–15.3% in beer, bread and dried corn. The incidences and mean levels of DON were 56% and 68.9 µg kg?1 for corn-based products, 49% and 24.1 µg kg?1 for wheat-based products, 43% and 7.5 µg kg?1 for barley-based products, and 16% and 3.4 µg kg?1 for rice-based products, respectively. The estimated daily intake of DON from the consumption of rice-based, wheat-based, barley-based and corn-based products were 0.0038 µg kg?1 bw day?1, 0.0032 µg kg?1 bw day?1, 0.0015 µg kg?1 bw day?1 and 0.0002 µg kg?1 bw day?1, respectively. These values represent 0.38%, 0.32%, 0.25% and 0.01% of the provisional maximum tolerable daily intake (PMTDI) of 1 µg kg?1 bw day?1. These results indicate that rice-based products are major contributors to DON exposure in Korea, even though the current exposure level is unlikely to cause adverse health effects.  相似文献   

15.
The paper’s main purpose is to estimate the dietary exposure to lead for the inhabitants of Jiangsu province, China. Lead concentration data were obtained from the national food contamination monitoring programme during 2007–10. Food samples (n = 2077) were collected from 23 food categories in Jiangsu province. Consumption data were derived from Chinese national nutrition and health survey in 2002, which included 3938 inhabitants from 1451 households in Jiangsu province. Concentration data were combined with consumption data to estimate the dietary intake for the inhabitants of 2–6, 7–17 and 18–80 years, respectively. The β-binomial–normal (BBN) model was used to estimate the long-term intake for the population in Jiangsu province. The distribution of individual margin of exposure (IMoE) was introduced to assess the health effect. Uncertainty of IMoE was quantified by Monte Carlo and bootstrap methods. The mean levels of dietary exposure to lead were estimated at 3.019 µg kg?1 bw day?1 for children aged 2–6 years, 2.104 µg kg?1 bw day?1 for teenagers aged 7–17 years, and 1.601 µg kg?1 bw day?1 for adults aged 18–80 years. The mean intakes for the urban and rural populations were 1.494 and 1.822 µg kg?1 bw day?1, respectively. From the 25th to 99.9th percentiles, IMoE was 0.125–2.057 for 2–6 years and 0.473–7.998 for 18–80 years, respectively. The distribution of IMoE could indicate a public health concern on lead for the Chinese population in Jiangsu. Control measures should be taken to reduce lead exposure in Jiangsu province.  相似文献   

16.
The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0–26.4 µg kg?1 (mean: 7.1 ± 7.2 µg kg?1). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l?1 (mean: 0.104 ± 0.138 µg l?1). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l?1) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5–153.3 µg kg?1 (mean: 57.6 ± 48.7 µg kg?1). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l?1. Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.  相似文献   

17.
A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, ipronidazole and there hydroxy metabolites hydroxymetronidazole, 2-hydroxymethyl-1-methyl-5-nitroimidazole, and hydroxyipronidazole. The method can also analyse for carnidazole, ornidazole, ternidazole, tinidazole, and chloramphenicol. A recommended level of 3 µg l?1/µg kg?1 for methods for metronidazole, dimetridazole, and ronidazole has been recommended by the Community Reference Laboratory (CRL) responsible for this substance group, and this method can easily detect all nitroimidazoles at this level. A minimum required performance level of 0.3 µg l?1/µg kg?1 is in place for chloramphenicol which the method can also easily detect. For nitroimidazoles, the decision limits (CCα) and detection capabilities (CCβ) ranged from 0.41 to 1.55 µg l?1 and from 0.70 to 2.64 µg l?1, respectively, in milk; and from 0.38 to 1.16 µg kg?1 and from 0.66 to 1.98 µg kg?1, respectively, in honey. For chloramphenicol, the values are 0.07 and 0.11 µg l?1 in milk and 0.08 and 0.13 µg kg?1 in honey. Validation criteria of accuracy, precision, repeatability, and reproducibility along with measurement uncertainty were calculated for all analytes in both matrices.  相似文献   

18.
The selenium concentration of potato tubers (cv. Mira) obtained from Shuan He, Enshi, Hubei, China is 0.16 mg kg?1 by fresh weight (0.64 mg kg?1 dry weight), but it is as high as 20–40 mg kg?1 on dry basis in various concentrates of potato protein. The experimental results indicated a linear relationship between the amount of the protein precipitated and that of selenium coprecipitated from potato juice. Selenium concentrations in ultrafiltration, ferric chloride and citric phosphate buffer concentrates are 5.12, 5.92 and 8.08 times higher than those in potato powder when their protein contents are concentrated 6.10, 6.65 and 7.08 times, respectively. These results are important relating to the production of valuable dietary supplements, e.g. pills, capsules or foods with Se‐level being accurately controlled applicable to selenium‐deficient areas. Recovery of selenium by precipitating proteins from potato juice is a time‐ and energy‐saving method may be applied to the establishment of a large‐scale processing plant.  相似文献   

19.
 Data about selenium (Se) concentrations in the environment and its daily dietary intake in Croatia are scarce. The aim of this study was to estimate daily dietary Se intake in a group of female subjects from the Zagreb area using three different approaches: direct measurement of Se in collected daily duplicate portions, daily dietary records and the indirect method of Se analysis in serum. The results were 33.2±8.82, 30.9±7.40 and 37.8±5.45 μg day–1 (arithmetic mean ±SD) by duplicate portion, daily dietary records and the serum Se method, respectively. The results of dietary Se intake estimation showed that Se intake for the observed group of female subjects from Zagreb area is lower than in the majority of European countries, and lower than the value recommended by the World Health Organisation. Received: 17 May 1999  相似文献   

20.
BACKGROUND: Folic acid (FA) is essential for healthy people (reference daily intake 400 µg day?1) and pregnant women (600 µg day?1). Insufficient intake of FA will increase the risk of neural tube defects in newborns. In this study an indirect enzyme‐linked immunosorbent assay was developed for rapid and convenient detection of FA in vitamin‐fortified foods. RESULTS: A carbodiimide‐modified active ester method was used to synthesise the immunogen (FA–bovine serum albumin (BSA) conjugate) to raise polyclonal antibodies for FA. The coupling ratio of FA with BSA was determined to be 14:1 (molar ratio). The detection limit of the immunoassay was 3.0 ng mL?1 in buffer, 3.52 ng mL?1 in energy drink, 11.91 ng mL?1 in milk and 16.50 ng mL?1 in milk powder. Intra‐ and inter‐assay variability ranged from 6.6 to 15.1%. Analytical recoveries of FA‐spiked samples were 88.3–108.9%. CONCLUSION: The immunoassay developed in this study can be used as a simple, rapid and accurate method for fast semi‐quantitative and quantitative on‐site analysis of FA in food products. Copyright © 2012 Society of Chemical Industry  相似文献   

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