Content of strontium, lithium and calcium in selected milk products and in some marine smoked fish.

The strontium, lithium and calcium contents have been determined in 87 samples of five kinds of milk-fermented products, as well as in 93 samples of ten kinds of marine smoked fish. The samples were purchased on the local market. The representative samples were dry ashed in quartz crucibles and the ash was treated with suitable amounts of conc. HCl and a few drops of conc. HNO3. The obtained sample solution was then used for the determination of Sr, Li and Ca by the flame atomic absorption spectrometry (AAS) method. Ca and Li were determined using the air-acetylene flame and Sr with nitrous oxide-acetylene flame, according to the manufacturer's recommendations. The contents of Sr in the fermented milk products ranged from 0.21 to 0.79 (mean 0.44 +/- 0.07) and in the marine smoked fish from 0.02 to 4.63 (mean 1.16 +/- 0.24) mg/kg of the edible form of both products. Li contents in the milk products ranged from 0.01 to 0.50 (mean 0.07 +/- 0.04) and in the smoked fish from 0.00 to 0.58 (mean 0.11 +/- 0.08) mg/kg. The calcium was highest in the milk products and ranged from 1,010 to 2,020.0 (mean 1,377 +/- 143) mg/kg. In the smoked fish calcium varied strongly and ranged from 40 to 1,052 (mean 303 +/- 53) mg/kg of the edible form. The calculated average ratio of strontium to calcium (mg Sr/1 g Ca) in the milk beverages and yogurts amounted 0.32 and in the smoked fish was 12 times as high and amounted 3.84. The main purpose of this work was to present Ca, Sr and Li together. This is justified because Sr and to some extent also Li are able to modulate Ca metabolism and vice versa.

[Amounts of selected minerals in green and black teas]. / Zawartosc wybranych skladników mineralnych w herbatach zielonych i czarnych.

The paper contains the results of 19 minerals (Ca, K, P, Na, Mg, Zn, Fe, Mn, Cu, F, Ni, Co, Cr, Li, Sr, Al, Cd, Hg, Pb) determined in green and black species of market teas. The examined minerals (except phosphorus, fluoride and mercury) were determined by ASA-method using air-acetylene flame (aluminium was determined in the nitrous oxide-acetylene flame). Mercury was determined by cold vapour method. The phosphorus and fluoride was determined by spectrophotometry methods (phosphorus in the form of phosphomolybdate blue and fluoride by use microdiffusion procedure where alizarin-fluoride complex was formed). It has been found that the examined teas are important source of potassium and low source of sodium, assuming a daily intake of 4 glasses of tea infusions. Tea drinking may be advantageous for hypertensive persons. The investigated teas are also important source of other examined minerals especially some microelements. The intake of the toxic metals with tea (Cd, Hg, Pb, Al) is low, from a centesimal to a few percent of the PTWI dose accepted by the FAO/WHO Experts. This paper presents also the first findings of the lithium and stronthium contents of examined tea species--whose physiological role still remains unknown.

Mercury and other trace metals (Ag, Cr, Co, and Ni) in soft tissue and byssus of Mytilus edulis from the east coast of Kyushu Island, Japan.

Concentrations of Hg and other metals such as Ag, Cr, Co and Ni in soft tissues and byssi of the blue mussel (Mytilus edulis) from three sites along the east coast of Kyushu Island, Japan, were determined by a cold-vapor technique. Large inter-regional differences in metal concentrations in both soft tissues and byssi were observed. The tissue concentrations of Hg were significantly greater in M. edulis from the most contaminated locations (Saganoseki) compared to those from a non-industrialized area (Urashiro). It is evident that, compared to the soft tissue, byssus is a more sensitive biomonitor for Hg, Cr, Co and Ni. From the data obtained in the present study evidently results that the soft tissue and especially byssi of M. edulis appear to be good bioindicators for identification of coastal areas exposed to Hg contaminants.

Distribution and relationships of selected trace metals in molluscs and associated sediments from the Gulf of Aden, Yemen.

Concentrations of Cd, Pb, Zn, Cu, Ni, Co, Cr, Mn and Fe in the soft tissue of Turbo coronatus, Acanthopleura haddoni, Ostrea cucullata and Pitar sp., as well as in associated surface sediments (bulk and bioavailable metal concentrations) from the Gulf of Aden, Yemen, were determined by atomic absorption spectrophotometry method. Large differences between size-classes of molluscs in metal concentrations were recorded. Significant spatial differences in metal concentrations in both the soft tissue of the molluscs and associated sediments studied were mostly identified. Statistically significant correlations (p<0.01) between concentrations of selected metals were observed. A slope of the linear regression is significantly higher than unity for Fe (9.91) and Cd (3.45) in A. haddoni and for Ni (4.15) in T. coronatus, suggesting that the bioavailability of these metals is disproportionally increased with a degree of enrichment of the sediments in Fe, Cd and Ni, respectively. A slope constant approximating to unity (1.14) for Cu in A. haddoni relative to its concentration in sediment extract implies that bioavailability of this metal proportionally increased with growing concentrations of its labile forms in the associated sediment. The degree of contamination of Gulf of Aden waters by the metals studied is discussed and the potential ability of molluscs, especially A. haddoni and T. coronatus, as biomonitors of metallic pollutants is postulated.

Aluminium determination in foods by using spectrophotometric oxine and flame AAS methods.

Results of aluminium determinations obtained by employment of N2O-C2H2 flame AAS method and spectrophotometric oxine (SO) method in teas, fresh leaves of celery and some other food samples were compared. The samples were digested for few hours in teflon beakers with use of a mixture of concentrated acids (H2SO4 + HNO3 + HCIO4), and then transported for final destruction into platinum dishes for ashing. The obtained stock sample solutions were used for examination by both methods. The accuracy was checked with recovery test of aluminium added to the samples before decomposition. With employment of AAS-method 83.3% to 100% (mean 94.2 +/- 8.1%) of added aluminium was recovered, and in the SO method from 86.4 to 109.3% (mean 98.6 +/- 5.2%). Great care is necessary for preparation of the blank. Food products containing higher levels of aluminium (i.e. teas and herbs) can be determined directly by the employed AAS-method using 1-2 g of samples for decomposition, while foods containing low levels of aluminium need use of larger samples for decomposition (i.e. 5-10 g or even more than 50 g in the case of strawberry or fresh leaves of celery) and the obtained ash should be dissolved to as low as possible of final volume of stock sample solution. The SO method is about 7 to 10 times more sensitive than the nitrous-oxide flame AAS method and enable to determined about 2.5 micrograms of Al per sample in form of oxine complex extracted into a 5 ml chloroformic phase. In the case of AAS-method the lowest determined level of aluminium amounted about 6 micrograms/ml of the examined sample solution. The results of both methods are strong correlated, as it is showed by the correlation coefficient (r = 0.97) at the level of significance alpha = 0.05.

[Composition of nutrients and minerals in some goat milk products]. / Zawartosc skladników pokarmowych w niektórych przetworach mleka koziego.

The paper contains results of determinations of protein, fat, carbohydrates, water and minerals (Ca, P, Fe, Mn, Cu, Zn, Na, K) in 12 goat milk products. The nutrient components were determined by general approved analytical methods. Minerals like Ca, Fe, Mn, Cu, Zn, Na and K were determined by the flame ASA method. Phosphorus was determined as phosphates by colorimetric method with ammonium molybdate. Mean percentage content of protein, fat, carbohydrates and water were: 9.7-25.7; 1.4-33.5; 2.2-70.2; and 3.0-77.4 respectively. The content of minerals according to the products of goat milk were as follow: 86-1113 mg% Ca; 96-846 mg% P; 0.2-2.4 mg% Fe; 6-148 mg% Mg; 0.002-0.284 mg% Mn; 0.071-0.754 mg% Cu; 1.1-3.9 mg% Zn; 63-1281 mg% K and 27-407 mg% Na. The levels of nutrients and mineral composition of the examined goat milk products were similar to that of the cows milk products.

[Evaluation of the health aspects of goat milk]. / Ocena jakosci zdrowotnej mleka koziego.

The work contains results of determinations of protein, fat, lactose, vitamin C and minerals: Ca, P, Fe, Mn, Cu, Zn, Na, K, Cl as well as toxic metals like Hg, Cd and Pb in goat milk. The nonmineral components were determined by general approved analytical methods. Minerals like Ca, P, Fe, Mn, Cu, Zn, Na, K, Cd and Pb were determined by the flame ASA method and mercury by "cold vapour" technique. Chloride were determined by Mohr method and phosphorus as phosphates by colorimetric method with ammonium molybdate. Mean percentage content of protein, fat, lactose and ash were: 3.2 (range 2.7-3.7); 3.9 (3.2-6.5); 4.1 (3.9-4.9); 0.87 (0.84-1.00) respectively. Mean content of ascorbic acid amounted 0.53 mg/100 g (range 0.19-1.42), and the content of minerals were as follows: Ca 130 (range 102-150); P 127 (115-151); Mg 14.1 (12.6-16.3); Mn 0.026 (0.019-0.037); Cu 0.04 (0.02-0.08); Zn 0.54 (0.40-1.25); Fe 0.047 (0.020-0.097); Na 42.4 (20.8-59.5); K 163 (138-190); Cl 168 (128-180). The levels of toxic metals were mostly below the allowable limits, mercury from 3.8 to 14.5 micrograms/kg, cadmium < 0.01 micrograms/kg. In the case of lead a 40% of investigated samples were above the allowable limits.

Aluminium and fluoride in hospital daily diets and in teas.

The levels of aluminium and fluoride have been determined in hospital daily diets including breakfast, dinner and supper, as well as in black teas and herbal teas purchased from the local market. In tea, aluminium was determined directly in a sample solution by atomic absorption spectroscopy using nitrous oxide and an acetylene flame. For analysis of the hospital diet, samples containing lower levels of aluminium were analysed using a spectrophotometric method which measured aluminium in the form of a 8-hydroxyquinoline complex. Decomposition of the samples was achieved using a mixture of concentrated acids [nitric (HNO3), perchloric (HClO4) and sulphuric (H2SO4)] in platinum dishes. Fluoride was assayed by spectrophotometry using a microdiffusion procedure with a mixture of concentrated HClO4 and silver sulphate, trace amounts of the released fluoride [as hydrogen fluoride (HF)] were trapped on the alkaline surface of a Petri dish and then determined in the form of an alizarin-fluoride complex. The mean level of aluminium found in hospital daily diets amounted to 21.3 +/- 12.3 mg and the mean level of fluoride was 1.38 +/- 1.12 mg per adult person. In the 16 samples of commerically available brands of black teas, the levels of aluminium and fluoride ranged from 445 to 1552 ppm (mean = 897 +/- 264 ppm) and from 30 to 340 ppm (mean 141 +/- 85 ppm), respectively. In six herbal teas, the mean levels of aluminium and fluoride were lower, and amounted to 218.9 +/- 150.7 ppm and 6.0 +/- 6.9 ppm, respectively. This study has shown that concern about a high intake of aluminium and fluoride from these foods is unfounded.

[Occurrence of aluminum in some foodstuffs]. / Wystepowanie glinu w niektórych srodkach spozywczych.

Results of aluminium determinations in breads and biscuits as well as in fish preserves, vegetables, strawberries and teas including fruit-herb teas are presented. Also the percent of extraction of aluminium of various kind of tea leaves into the infusions was determined. The commercially available sample of foods was used for investigation. Aluminium was determined by using two methods: a spectrophotometric extraction method with-hydroxyquinoline and less sensitive AAS method with nitrous oxide-acethylene flame on PU 9100X Philips Spectrometer could with IBM compatible Computer (Hundai) provided with 9178/9X Flame Program Unicam Limited--1991. The sample was at first digested with mixture of concentrated acids (H2SO4 + HNO3 + HClO4) in teflon vessels and then finished in platinum dishes. Solutions of the destroyed samples was kept in polethylene bottles. The methods was checked by recovery tests. In the 8-hydroxyguinoline-extraction-method about 88.5% to 106.5% of the added aluminium was determined and in the AAS method it was of 75% to 100%. The highest level of aluminium was found in the eas: from 445 to 1522 mg/kg (mean 879 mg/kg) and then in herb-fruit teas (consisting of dried herbs and fruits of sloe plum, briar-rose juneberry Aronia etc.) from 45 to 379 mg Al/kg of dry matter. About 29% of the metal was extracted from teas into the infusion. Lower levels was found in breads (0.0-92.0 mg mean 29.95 mg/kg) and in the fish preserves (0.0-57.0 mg mean 18.1 mg AL/kg). Similar levels were also found in 7 kinds of popular vegetables (0.0-100 mg mean 33.3 mg Al/kg). The lowest levels was found in strawberries (0.50-3.0 mg Al/kg). It was calculated that drinking three glasses of tea daily may supply about 2.6 to 3.7% of the provisional tolerable weekly intake dose set by the Joint FAO/WHO Expert Committee. It is concluded that the obtained results are similar to those published by other authors and represents a levels normally encountered in foods, and do not create any risk for human consumption.

[The content of nitrates and nitrites in fruits, vegetables and other foodstuffs]. / Zawartosc azotanów i azotynów w owocach i warzywach oraz w niektórych innych srodkach spozywczych.

There are presented the results of the investigation of many popular fresh and frozen vegetables as well as in fresh and frozen fruits, such as different kind of apples, strawberries, currants, raspberries and many other tender fruits mainly from market and few from own allotment-cottages performed in the year 1989-1992. The nitrate and nitrite was determined according to the Griess reaction. High levels of nitrate was encountered in lettuce, frozen spinach, fennel, radishes, parsley. Many of this samples contained more than 1000 mg of KNO3/kg of fresh product, but the highest level, over the 3500 mg/kg was found in lettuce. The remaining vegetables like carrots, celery, leeks and frozen French bean contained from several dozen to more than 800 mg KNO3/kg. The level of nitrite in all samples of the investigated vegetables and fruits was very low from zero to decimal part of milligram per kg. Very low level of nitrate was found in 7 species of investigated apples (from 1.3 to 9.7 mg KNO3/kg). A little higher level of this compound was ascertained in currants, gooseberries, raspberries, cherries (from 0.0 to 36.0 mg KNO3/kg product). The highest levels of nitrate occurred in samples of strawberries (maximum to 322.3 mg KNO3/kg) but mean level amounted 58.7 mg KNO3/kg. The encountered levels of nitrate in frozen vegetables and fruits as well as in jams and stewed fruits was only little less than in fresh products. Very high level (from 355.30 to 584.53 mg KNO3/kg) was ascertained in the fruit-vegetable juice named "Rinberen" and "Malberen" to which red beet extract was used for their production. It should be pointed out that when the containers of these juice was opened and stored at the room temperature (+20 degrees C) during 30 days, no changes was observed in the level of nitrate and nitrite. In the juice prepared from blanched carrot, the rate of the reduction of nitrate to nitrite has not been lowered, when this product was storage of this juice at room temperature, the mean level of nitrite increased significantly (from 0.14 to 82.89 mg NaNO2/kg) and the level of nitrate lowered from 261.0 to 46.4 mg KNO3/kg. It should be strongly recommended for consumption the juices from carrot only fresh prepared. There are also presented the results of investigation of nitrate in fermented cheeses.(ABSTRACT TRUNCATED AT 400 WORDS)

[New look at problems of assessment and tolerance of certain carcinogens in food in view of the literature]. / Nowe spojrzenie na problem oceny i tolerancji zwiazków rakotwórczych w zywnosci w swietle pismiennictwa.

The present approach to the assessment of carcinogens in food is described in the light of a literature review. In accordance with Delaney clause, these compounds should not be found in food. The advances in analytical methods have shown, however, that it is not possible to avoid the presence of trace amounts of carcinogens, natural as well as synthetic. On the basis of the maximal tolerated dose (MTD) established in animal studies the power of cancerogenic activity of many compounds was determined as expressed by the dose producing cancer development in 50% of the experimental animals. This dose has the symbol TD50, analogously to the LD50 symbol used in toxicology. On the basis of these doses a trial is presented of ranking carcinogenicity++ using a new index HERP which expressed the per cent of the amount of a compound taken with food in relation to TD50. Trials are mentioned also of estimating health risk on the basis of evaluation of the risk of malignancy development due to intake of a compound with food, according to the "de minimis" doctrine.

[Comparison of results for evaluating calcium and phosphorus content in children's daily diets obtained by analytical methods and calculations]. / Porównanie wyników oznaczania zawartosci wapnia i fosforu w calodziennych dietach dzieci metodami analityczna i obliczeniowa.

The results of two methods for the estimation of calcium and phosphorus in daily rations of children aged up to 1 year were compared by simple statistical tests. Ca and P contents were determined by the analytical method; moreover, the theoretical Ca and P contents were calculated from the bills of fare menus and food composition tables. The analytical procedure was accepted as reference method. Ca and P contents determined by the analytical method accounted, on the average, for ca. 90% of those obtained by the calculation method. The coefficients of correlation between the results obtained by both methods (x and y) amounted to: rCa = 0.456 and rP = 0.786. There were significant differences between Ca and P contents obtained by both methods at significance level alpha = 0.05.

[Problem with the presence of carcinogenic substances formed spontaneously or during technologic processing in food]. / Problem obecnosci w zywnosci powstajacych naturalnie oraz tworzacych sie w czasie procesów technologicznych zwiazków rakotwórczych.

The current opinion on the spontaneously occurring or evoked by certain culinary and technological processes muta-, cancero- and teratogenic compounds are reviewed on the basis of the world literature. It was noted that these substances may form in food products of vegetal origin. Formation of carcinogenic compounds is more intensive in plants attacked by various diseases, insects or parasites. The importance of this problem should be stressed together with the need of improving knowledge in this field. The compounds under discussion are the most serious risk factor in the incidence of neoplasms in humans.

[Presence of nitrates and nitrites in baker's products and in certain other flour products]. / Wystepowanie azotanów i azotynów w pieczywie oraz niektórych innych przetworach z maki.

The results of the study demonstrated that the content of nitrates and nitrites in various baker's products varied from 0.96 (in wheat rolls and baguettes) to 44.07 mg KO3/kg in pumpernickel bread. In wholemeal bread, village bread, tourist bread, rye brown bread and Graham bread the content of these compounds was from 1.46 to 27.10 mg KNO3/kg. The mean content of nitrites in these bread sorts was 1.76 mg NaNo2/kg, range 0.10-4.40 mg NaNo2/kg. In white wheat flours (Wroclaw flour, cake flour and Poznan flour) the content of nitrates ranged from 1.10 to 19.08 mg KNO3/kg, and in the dishes produced from them in household was from 0.50 to 16.33 mg KNO3/kg. The content of nitrites in these flours was in the range from 0.00 to 4.16 mg NaNo2/kg, and in the products prepared from them it was from 0.00 to 1.60 mg NaNO2/kg. Eleven types were tested also of popular biscuits, wafers, gingerbread and hard cakes in which the content of nitrates was from 3.66 to 17.72 mg/kg, and that of nitrites was from 0.00 to 8.80 mg NaNo2/kg. Considering the average consumption of these products per one person in the seashore region and the mean values of nitrates and nitrites it was calculated that they provided daily about 3.9 mg KNO3 and 0.4 NaNo2, that is about 1.8% of nitrates and 7.7% of nitrites consumed by adults in daily food ration.

[Occurrence of nitrates and nitrites in certain frozen fruits, jams, stewed fruit and fruit-vegetable juices for children and in certain types of bee honey]. / Wystepowanie azotanów i azotynów w wybranych mrozonkach owocowych, dzemach, kompotach i sokach owocowo-warzywnych dla dzieci oraz w niektórych miodach pszczelich.

Nitrates and nitrites were evaluated spectrophotometrically by the method of Griess reaction, with previous reduction of nitrates to nitrites in a column filled with cadmium dust. The content of nitrates in frozen fruit (strawberries, black and red currant and plums) ranged from 2.50 to 57.38 mg KNO3/kg, with the highest content in garden strawberries. In cherry, strawberry, black and red currant jams the concentrations were from 6.30 to 97.38 mg KNO3/kg, the highest content was in cherry jam. In plum jam nitrates were found in low amounts from 11.65 to 12.09 mg/kg. In "Bobofrut" juices the nitrate content was higher than in the above products, ranging from 26.37 to 182.75 mg KNO3/kg. Nitrite content in all these groups of products was low, not exceeding 1 mg NaNO2/kg, with the exception of plum jam where the maximal value was found 1.65 mg NaNO2/kg. In stewed fruit and herb syrups and in honey nitrates ranged from 1.0 to 94.5 mg KNO3/kg. Nitrite content ranged from 0.17 to 1.92 mg/kg in herb syrups, from 0.0 to 1.20 mg/kg in stewed fruit, and from 0.0 to 0.40 mg NaNO2/kg in honey. The study showed that higher levels of nitrates were present as a rule in vegetable juices. However, the found concentrations were not harmful to the health of children, although this is possible in the case of carrot juice, especially when kept at room temperature for 24 hours.

[Changes in the levels of nitrates and nitrites in vegetables and vegetable products and vitamin C in white sauerkraut]. / Zmiany zawartosci azotanów i azotynow w warzywach i przetworach warzywnych oraz witaminy C w bialej kapuscie kiszonej.

The authors demonstrated that during souring nitrates disappear from the white sauerkraut as a mean rate of 42% after 7 days and 23% after 30 days (souring in spring 1987) and by 29% and 77% of the initial level after 7, 30 and 90 days (souring in winter-spring period 1988). After 7 days the level of l-ascorbic acid rose from a mean value of 52 mg/kg to 300 mg/kg, and after 90 days this level fell to one-half of the initial value. No significant changes were noted in the content of nitrites. A decrease of nitrates and increase of nitrite content was found in freshly obtained carrot juice (with a juice extractor). The effect of time and temperature of juice storage on the concent of nitrates and nitrites was studied.