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Summary
Extensive use of coffee, by one-third of world's population, entails the evaluation of trace element contents in it. Instrumental neutron activation analysis (INAA) was successfully employed to determine the concentration of 20 trace elements (essential, toxic and nonessential) in four samples of coffee beans of various origins and two instant coffee brands most commonly consumed in Pakistan. This study provides the base-line values of certain toxic and essential elements in coffee. The daily intake of essential and toxic elements through coffee was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits.
Abstract
The soil-to-grass transfer factors and grass-to-milk transfer coefficients were determined for 137Cs and stable Cs in soil, grass and milk samples collected in Aomori Prefecture, Japan. The concentrations of 137Cs in the soil and grass samples collected from 25 sampling sites were 13±12 Bq.kg-1 and 2.0±2.1 Bq.kg-1 dry wt., respectively. The geometric mean of soil-to-grass transfer factor of 137Cs was 0.13 and its 95% confidence interval was 0.017-0.98. The transfer factor of 137Cs was higher than that of stable Cs, and they had a positive correlation. The concentration of K in the soil affected both transfer factors. The concentration of 137Cs in milk samples collected from 16 sites was 76±43 mBq.kg-1 fresh wt. and had a good correlation with that of stable Cs. The geometric mean of grass-to-milk transfer coefficient of 137Cs was 0.0027, assuming that a cow's total daily intake was 20 kg of dry grass. The transfer coefficient of 137Cs was positively correlated with that of stable Cs.
Abstract
Concentrations of 15 elements were determined simultaneously in duplicateportion diets of two university student groups from S
o Paulo Universityconsisting of nine women (20–23 years) and ten men (20–24 years).Thediet samples were prepared by either freeze-drying or drying in a ventilatedoven. About 100–200 mg of diets were irradiated for 2 minutes and 8hours in the IEA-R1m research reactor and Br, Ca, Cl, Co, Cr, Cs, K, Fe, Mn,Mg, Mo, Na, Rb, Se, and Zn were determined by instrumental neutron activationanalysis (INAA). The average daily intakes found in the women and men groupswere: 2.1 and 4.3 mg of Br, 501 and 707 mg of Ca; 3.1 and 6.0 g of Cl; 12and 25 mg of Co; 15 and 36 µg of Cs; 53 and 63 µg of Cr; 5.1 and10.8 mg of Fe; 1.3 and 2.8 g of K; 134 and 306 mg of Mg; 1.3 and 4.1 mg ofMn; 134 and 302 mg of Mo, 2.0 and 4.1 g of Na; 2.4 and 4.6 mg of Rb; 29 and41 µg of Se; 6.2 and 10.6 mg of Zn, respectively. The daily intakesof Ca, Se and Zn in both groups and Fe in the women groups appeared to bebelow the U.S. RDA recommendations. For the elements Na and Cl the daily intakeswere higher than the recommended values by RDA.
Abstract
Tea has been one of the most popular simulating beverages which is both heavily produced and consumed in Taiwan. The determination of minor or trace elements in drinking tea and tea leaves is therefore important for estimating the daily intake of Taiwanese considered as a safety indicator. In order to accurately and precisely determine the concentrations of trace elements in samples, several analytical methods such as AAS, NAA and ICP-AES are suggested. This paper attempts to utilize all three methods to determine the concentrations of minor or trace elements in different types of tea leaves and the extracts percolated from them. The influence of fermentation processes on the concentration levels of minor or trace elements in tea samples is investigated. Because only free metal ions are bioavailable for the human body, it is necessary to determine their concentrations in drinking tea. The dissolution of trace elements in drinking tea is therefore studied by simulating the common Chinese style of tea percolation. Concentrations of thirteen elements including Zn, Mn, Ca, Cu, Ni, Al, K, Mg, Cd, Pb, Na, Co and Sc are determined.
Abstract
The concentration of certain toxic and essential elements in various raw materials of Chinese herbs and 
scientific Chinese medicine
were determined by atomic absorption spectrometry (AAS) and instrumental neutron activation analysis (INAA). Correlation of these elements as they exist in the raw materials and in the prescription of medicine were investigated and the approximate intake of elements by patients were estimated. Values of elements determined both by ASS and INAA presented excellent agreement. The ranges of elemental concentrations were found to vary from 104 to 10–1 mg/kg in different kinds of herbs. All herbs exhibit extraordinary enrichment capabilities from the environment for elements such as Mn, Zn, Ca, K, Mg, Cd, Cu, Pb and As. Higher contents of Cd, Pb and As in herbs may be attributed to the uptake of these elements from polluted soil due to industrial and antropogenic activities. It was found that commercial scientific Chinese medicine, SCDBT, contains more elemental concentrations than that of herbs used in the prescription, which may indicate that possible contamination could be caused by unknown ingredients added in the process. A much higher toxic elemental content, such as Pb, Cd and As, has been found in CFH and the daily intake of these elements by the patient will exceed the PTDI values.
Abstract
The intake and tissue distribution of thorium (2 3 2Th) was studied in an urban (Bombay) population in India. From the analysis of 16 whole diet samples, the average daily intake through food was found to be 2 
g (range 0.8–4.3 g·d–1). The estimated intake through drinking water and inhalation comes out to be 0.03 and 0.02 g per day. From the analysis of human autopsy tissue samples it is observed that the concentration ranges in lungs and bone are 1.5–16 g/kg and 0.2–9.0 g/kg fresh weight respectively. The average urinary concentration is 12 ng/1 (range 7–22 ng/l for 10 samples). Among the different body tissues, pulmonary lymph nodes were found to contain the highest concentration (geometric mean 53.4 g/kg, range 31.4–85.5 g/kg for 6 samples). Analysis of the samples was done by the neutron activation technique. 311.8 keV gamma photons of2 3 3Pa which is the activation product of2 3 2Th, were counted after chemical separation. A 54 cm3 intrinsic Ge detector coupled to 1024-channel analyser was used. Using the average lung content and the daily average intake values of thorium through inhalation, the clearance half-time from lung was estimated.
Abstract
Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. However, very few surveys of radioactivity in food have been conducted in Ghana. The natural radionuclides 226Ra, 228Ra, 228Th and 40K were measured in the foodstuffs using gamma ray spectrometry. All samples were found to contain high 40K content in the range 87.77–368.50 Bq kg−1. The maximum concentration of 228Th and 40K were found in cassava to be 14.93 ± 3.86 and 368.50 ± 19.20 Bq kg−1, respectively. The total annual committed effective dose was estimated to be 4.64 mSv. The daily intake of radionuclides from food consumption reveals that cassava and plantain are the highest contributors, while millet is the lowest. The daily radionuclide intake from the foodstuffs consumed by the general public was 411.32 Bq and the daily internal dose resulting from ingestion of the radionuclides in the foodstuffs was 0.01 mSv. The radionuclide concentrations were comparable with those reported from other countries.
Abstract
In the under developed countries, the people of far-flung rural areas still depend to a large extent upon herbal medicines. At the foundation of usage of herbal medicine is the experience of thousands of years. The present paper deals with the characterisation of exotic fruits for essential and toxic elements. The samples include Morus nigra, Morus alba, Salvadora persica and Carissa opaca (from low and high altitude). Two standardizations of neutron activation analysis, that is, semi-absolute k 0-instrumental neutron activation analysis (k 0-INAA) and epithermal neutron activation analysis (ENAA) were employed for the quantification of elements. The analysis methodologies were validated by analyzing the IAEA-336 (lichen) and NIST-SRM-1572 (citrus leaves). Sixteen elements including Br, Ca, Cl, Co, Cr, Fe, I, K, Mg, Mn, Na, Rb, Sb, Sc Sr, and Zn were determined in all samples. Daily intakes of various elements from the samples were measured and compared with the dietary reference intakes. Additionally, principal component analysis was performed to extract information regarding samples and elements.
Abstract
Mineral contents of strawberry, collected from different farms of Islamabad were analysed by semi-absolute k 0-instrumental neutron activation analysis and atomic absorption spectrophotometry. The samples were irradiated at two research reactors located in Pakistan Institute of Nuclear Science & Technology (PINSTECH), Islamabad. The analytical methodologies were validated by analysing reference materials, IAEA-336 (lichen) and IAEA-V-10 (hay powder). In all the samples, a total of 26 elements were quantified, among them 16 elements (Ca, Cd, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Pb, Ru, Sc, Sr and Zn) were found in all the samples. The determined elemental concentrations in strawberry were compared with the reported values from other countries. In comparison with the mineral contents of other fruits, strawberry stands best source of Mn and the second most important source of K after banana. Intake of trace metals through this source was calculated and it was found that strawberry provides Mn (1.95–3.68 mg/kg), Cr (19.2–46.3 × 10−3 mg/kg), Fe (3.45–8.72 mg/kg), K (1,520–1,670 mg/kg) and Mg (100–220 mg/kg), which forms 26, 19, 14, 7 and 7% of the recommended dietary allowances for the respective metals. The daily intake of Cd and Pb were compared with the provisional tolerable weekly intake defined by FAO/WHO.
Abstract
Excessive consumption of salt causes many diseases, including high blood pressure and cardiovascular system disease. In most countries, salt intake is above the WHO guideline daily intake. In Hungary, the average salt intake is more than double the recommended value. Based on these, significant changes are needed in food technology and recipes. To avoid excessive salt intake Hungary has joined the European Union's community program for salt reduction.
The aim of this study was to compare the salt content in different areas of Mangalitsa ham during the dry salting, and compare the average salt content with the regulations of the Codex Alimentarius Hungaricus. The ham was dry salted with 10% by weight of the meat and placed in a controlled atmosphere storage room. The curing took 21 days. The NaCl uptake was measured with Mohr method. The ham was cut at 3 points Cushion (C), Fore Cushion (FC) and Butt End (BE). The salt content of BE was generally higher than the other two areas (C, FC). The differences can be explained by the difference in the thickness of the pieces of meat and fat. The average salt content of the different areas did not exceed the threshold limit in the Codex Alimentarius Hungaricus. At the beginning of the experiment, the salt content of each meat layer was very different, the absorbed salt was concentrated in the surface layer. Over time, as the ham lost a lot of water and due to the lack of outer salt, a significant increase in salt content began in the meat centrum. By day 80, the salt content of the meat centrum exceeded the salt content of both the fat and the surface layer.
