PubMed Health⌕ Search

Biomedical subjects

M Krachler

Publications and source records attributed to M Krachler.

At least 19 recordsLinked to original sources

Critical assessment of the performance of electronic moisture analyzers for small amounts of environmental samples and biological reference materials.

Two electronic moisture analyzers were critically evaluated with regard to their suitability for determining moisture in small amounts (< or = 200 mg) of various environmental matrices such as leaves, needles, soil, peat, sediments, and sewage sludge, as well as various biological reference materials. To this end, several homogeneous bulk materials were prepared which were subsequently employed for the development and optimization of all analytical procedures. The key features of the moisture analyzers included a halogen or ceramic heater and an integrated balance with a resolution of 0.1 mg, which is an essential prerequisite for obtaining precise results. Oven drying of the bulk materials in a conventional oven at 105 degrees C until constant mass served as reference method. A heating temperature of 65degrees C was found to provide accurate and precise results for almost all matrices investigated. To further improve the accuracy and precision, other critical parameters such as handling of sample pans, standby temperature, and measurement delay were optimized. Because of its ponderous heating behavior, the performance of the ceramic radiator was inferior to that of the halogen heater, which produced moisture results comparable to those obtained by oven drying. The developed drying procedures were successfully applied to the fast moisture analysis (1.4-6.3 min) of certified biological reference materials of similar provenance to the investigated the bulk materials. Moisture results for 200 mg aliquots ranged from 1.4 to 7.8% and good agreement was obtained between the recommended drying procedure for the reference materials and the electronic moisture analyzers with absolute uncertainties amounting to 0.1% and 0.2-0.3%, respectively.

Adsorption↗

Clinical laboratory parameters in osteoarthritic knee-joint effusions correlated to trace element concentrations.

Interactions of clinical laboratory parameters with trace elements in knee-joint effusions might turn out to be potential diagnostic tool, increasing our pathophysiological understanding and knowledge on knee-joint effusions. Thus, the 11 clinical laboratory parameters, total protein, albumin, glucose, lactate dehydrogenase, uric acid, pH, rheumatoid factor, antistreptolysin, C-reactive protein, leukocyte, and erythrocyte counts were determined in 39 osteoarthritic knee-joint effusions and in corresponding sera. Additionally, concentrations of the 17 trace elements barium, beryllium, calcium, cadmium, cesium, copper, lanthanum, lithium, magnesium, molybdenum, lead, rubidium, antimony, tin, strontium, thallium, and zinc in both effusions and corresponding sera were quantified by inductively coupled plasma-mass spectrometry. Concentrations of most laboratory parameters in synovial fluid were within the normal ranges for serum. However, concentrations of total protein and albumin in effusions were distinctly lower than in sera of healthy adults. Results for rheumatoid factor, antistreptolysin, and C-reactive protein in the effusions were below their corresponding threshold values for serum. An indicator for inflammation, the leukocyte count had a median < 6.3 G/L. The erythrocyte count (median: < 0.06 T/L) revealed a very low presence of red blood cells in the effusions. Total protein concentrations and lactate dehydrogenase activity in the effusions correlated positively with effusion copper (r = 0.61 and 0.66) and effusion zinc (r = 0.71 and 0.49). For cesium, a negative correlation in both sera (r = -0.44) and effusions (r = -0.44) with LDH activity could be established. Concentrations of rubidium, strontium, and cesium responded to albumin concentrations in sera and in effusions, establishing an inverse correlation. All other trace elements showed no or only weak associations with the clinical laboratory parameters determined. Although distinct relationships between trace element concentrations and clinical laboratory parameters in knee-joint effusions exist, the clinical relevance of these findings needs to be further elucidated.

Adult↗

Extraction of antimony and arsenic from fresh and freeze-dried plant samples as determined by HG-AAS.

Six extraction media (acetic acid, EDTA, tetrabutylammonium hydroxide, NaOH, MeOH/H2O, acetonitrile/H2O) were tested for their ability to extract antimony (Sb) and arsenic (As) from freeze-dried poplar leaves, pine shoots and spruce shoots, as well as from a peat matrix. Additionally, the extraction efficiency of Sb and As in fresh and freeze-dried elder leaves and poplar leaves was compared. Total concentrations of Sb and As of aliquots (approximately 220 mg) of the freeze-dried samples were analysed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) after open vessel digestion with adequate mixtures of nitric, sulfuric, hydrochloric, and perchloric acid. Three reference materials GBW 07602 Bush Branches and Leaves, GBW 07604 Poplar Leaves, and SRM 1575 Pine Needles were analysed with every batch of samples to ensure the accuracy and precision of the applied analytical procedures. The use of hydrofluoric acid in the digestion mixture leads to distinctly lower As values (down to 40%) than actual concentrations in the investigated plant materials. Extraction efficiencies were generally low and lower for Sb than for As. Solutions of 0.66 mol L(-1) NaOH liberated highest amounts of Sb with approximately 10% for poplar leaves, and approximately 19% each for pine shoots and spruce shoots. Distinctly higher concentrations of As in NaOH extracts of poplar leaves (22%), pine shoots (32%), and spruce shoots (36%) were quantified. Extraction experiments resulted in yields of 7-9% from fresh elder and poplar leaves, respectively, and 8-13% for freeze-dried samples for Sb. The corresponding values for As were 10-35% for the fresh material and 7-37% for the freeze-dried samples.

Antimony↗

Maternal selenium status in Slovenia and its impact on the selenium concentration of umbilical cord serum and colostrum.

OBJECTIVE: The aim of this study was to assess serum selenium (Se) level of Slovenian mothers at birth and to elucidate its impact on the Se content of umbilical cord serum of their newborns and of that of colostrum. SUBJECTS AND METHODS: In sera of 20 Slovenian mothers at delivery and in the corresponding umbilical cord sera of their newborns Se concentrations were determined by hydride generation atomic absorption spectrometry (HG-AAS). In addition Se levels in 10 healthy female blood donors were determined. Colostrum samples of 18 mothers collected on the second and third day post partum were also investigated for their Se content. RESULTS: Serum Se concentrations of mothers showed to be 62+/-15 microg/l. Umbilical cord sera had 34+/-7 microg/l, which amounts to 55% of the maternal content. Concentrations of Se in colostrum ranged from 17 to 48 microg/l with a mean of 29+/-10 microg/l. In the sera of female blood donors the mean was 66+/-15 microg/l. A significant correlation (P<0.002) between the Se content of maternal and umbilical sera could be established. No significant correlation was found between maternal serum Se concentration and that of colostrum. CONCLUSIONS: Our data show that dietary Se intake for pregnant women in Slovenia is borderline.

Adult↗

Reference values for chromium, nickel and vanadium in urine of youngsters from the urban area of Rome.

In the assessment of human health risk, the obtainment of reference values in biological tissues and/or fluids is crucial to estimate the type and magnitude of occupational and environmental exposure. In this context, urine is the major excretion route for many noxious substances that have entered the organism and can be viewed as one of the most useful materials for biomonitoring campaigns. In this study, reference concentration ranges for Cr, Ni and V in urine were achieved in a sub-population of 131 youngsters, aged 6-10, attending primary schools in the urban area of Rome. Subjects under drug therapy or affected by any pathological diseases were not included in this investigation. Strict precautions against contamination or loss of the analytes of interest were adopted for all steps. Determinations were performed by means of high resolution inductively coupled plasma mass spectrometry. In general, the natural log-transformed concentration data for the three elements investigated conformed to a satisfactorily normal distribution. The estimated reference ranges were as follows (microg g(-1) creatinine): Cr, 0.07-0.76; Ni, 0.20-1.23; V, 0.02-0.22. The sex of the youngsters was tentatively treated as a statistical explanatory variable using the Fischer F-test on variance.

Child↗

Investigation of the transport of trace elements across barriers in humans: studies of placental and mammary transfer.

UNLABELLED: The barrier function of the human mammary gland for selected trace elements was evaluated by analysing 27 maternal sera and corresponding colostrum samples for 14 trace elements. To investigate the impact of the human placenta at the end of gestation on the transfer of 17 trace elements from the mother to the baby, 29 maternal and corresponding umbilical cord sera (UCS) were studied. The uptake of trace elements from the UCS by the fetus was investigated in nine pairs of arterial and venous UCS. In colostrum, the concentration of Cu was 19%, of Se 47%, of Co 80%, of Mg 146%, of Ca 222%, of Sn 228%, of Mn 275%, of Mo 814%, and of Zn 1470% of that of the maternal sera. For Cd and Pb the corresponding values were 200% and 325%, respectively. These data show that the mammary gland can exert an activating as well as an inhibiting effect on the trace element transfer. A concentration gradient mode of action for the transfer of Li, Mo and Sr could be found. In UCS the concentration of Cu was 20%, of Se 55%, of Co 60%, of Sn 85%, of Mo 100%, of Mg 105%, of Ca 120%, of Zn 148%, and of Mn 150% of that of the maternal sera. The corresponding values for Cd were 66% and for Pb 50%. CONCLUSIONS: These findings indicate that the placenta can exhibit an activation or inhibition on transfer as well as a gradient mode of action as for Mo, Cs, Li and Sr. The uptake of essential trace elements from venous UCS by the unborn ranged from 2.5% for Ca to 16.7% for Mo. Both the placenta and the mammary gland can exert an activating, inhibiting or gradient mode of action for selected trace elements, the biological impact of which needs to be further elucidated.

Adult↗

Concentrations of trace elements in extensively hydrolysed infant formulae and their estimated daily intakes.

The 18 trace elements Ba, Be, Bi, Cd, Co, Cs, Cu, La, Li, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn were determined in three extensively hydrolysed formulae by inductively coupled plasma mass spectrometry. Two formulae were whey hydrolysates, whereas one was based on soy-bovine collagen hydrolysate. Two skim milk powder reference materials, analyzed to ensure the analytical precision and accuracy of the applied procedure, showed good agreement with the certified values. Most of the elemental concentrations in this three formulae were comparable to each other. However, concentrations of Cs in one formula were approximately 20 times higher than in the other two formulae. Another formulae had much higher concentrations of La and Mn compared to the other two formulae. As regards Rb, all three formulae had distinctly lower concentrations than the four pre- and nine follow-up formulae investigated in a previous study. For the essential trace element Sn, much higher concentrations were found in the three extensively hydrolysed formulae ( approximately 8 microg/kg) when compared to pre- and follow-up formulae (most of them <0.44 microg/kg). The concentrations of the toxic trace elements Cd, Pb, Sb, and Tl in extensively hydrolysed formulae did not exceed the concentrations in cow-milk-based formulae. Daily intakes provided by the investigated formulae differ by a factor of 1.6 for Co, of 3.2 for Cu, of 8.7 for Mn, of 4.8 for Mo, and of 1.5 for Zn. Adequate daily intakes for Cu, Mo, and Zn are guaranteed by the use of most formulae, whereas only one hydrolysed formula fulfilled these requirements for manganese. Two hydrolysed formulae provide only approximately 50% of the recommended intakes for Mo.

Animals↗

Long-term changes of plasma trace element concentrations in chronic hemodialysis patients.

BACKGROUND: Hemodialysis (HD) patients are at risk of developing trace element imbalances. METHODS: The 12 trace elements Cd, Co, Cs, Cu, La, Mg, Mo, Pb, Rb, Sr, Tl and Zn were determined in the plasma (n = 52) of 6 chronic HD patients before and after HD sessions by inductively coupled plasma mass spectrometry. Plasma trace element concentrations were monitored for 6 months. Baseline data have been compared to the concentrations at the end of the observation period to identify a potential reduction or accumulation of trace elements in HD patients. RESULTS: Plasma Cd, Co and Pb levels were about 10 times higher than in healthy adults. Concentrations of Co and Pb increased during HD sessions, whereas plasma Co and Cd increased during the study period of 6 months. Plasma Cs, Mg, Mo and Rb continuously decreased in all patients. For plasma Cu and Zn, a statistically significant rise of their plasma concentrations during HD and during the period of 6 months could be established. Concentrations of La and Tl did not change distinctly. CONCLUSION: This study revealed that plasma trace element concentrations in HD patients are distinctly different compared to that of healthy adults. Elements such as Cs, Mg, Mo and Rb are reduced and Cd, Co and Pb are accumulated in HD patients. Further studies are needed to elucidate the clinical impact of these trace element imbalances.

Adult↗

Concentrations of trace elements in osteoarthritic knee-joint effusions.

Concentrations of the 18 elements, barium (Ba), beryllium (Be), bismuth (Bi), calcium (Ca), cadmium (Cd), cesium (Cs), copper (Cu), lanthanum (La), lithium (Li), magnesium (Mg), molybdenum (Mo), lead (Pb), rubidium (Rb), antimony (Sb), tin (Sn), strontium (Sr), thallium (Tl), and zinc (Zn), were determined in the synovial fluids of osteoarthritic knee joints and in the corresponding sera of 16 patients by inductively coupled plasma-mass spectrometry. Knee-joint effusions have lower elemental concentrations than their corresponding sera. For the essential elements Ca, Cu, Mg, and Zn and for the nonessential and toxic elements Ba, Be, Bi, La, and Sb, this difference was highly significant. Strong positive correlations between concentrations in effusions and sera for the essential elements Cu and Mg and for the nonessential elements Cs, Li, Rb, and Sr could be established. The grade of localized hyperperfusion of the knee region in the blood pool phase of 99mTc HDP bone scan indicating inflammation did not correlate with any elemental concentration determined.

Adult↗

Concentrations of selected trace elements in human milk and in infant formulas determined by magnetic sector field inductively coupled plasma-mass spectrometry.

Magnetic sector field inductively coupled plasma-mass spectrometry (ICP-MS) was applied to the reliable determination of the 8 essential trace elements cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), selenium (Se), and vanadium (V) as well as the 7 nonessential and toxic elements silver (Ag), aluminum (Al), arsenic (As), gold (Au), platinum (Pt), scandium (Sc), and titanum (Ti) in 27 transitory and mature human milk samples and in 4 selected infant formulas. This advanced instrumentation can separate spectral overlaps from the analyte signal hampering significantly the determination of many trace elements by conventional ICP-MS. Moreover, superior detection limits in the picogram per liter range can be obtained with such magnetic sector field instruments. Therefore, this is the first study to report, the concentrations of the elements Ag, Au, Pt, Sc, Ti, and V in human milk and in infant formulas. Concentrations of Ag (median: 0.41 microg/L; range: < 0.13-42 microg/L) and Au (median: 0.29 microg/L; range 0.10-2.06 microg/L) showed large variations in human milk that might be associated with dental fillings and jewelry. Pt concentrations were very low with most of the samples below the method detection limit of 0.01 microg/L. Human milk concentrations of Co (median: 0.19 microg/L), Fe (380 microg/L), Mn (6.3 microg/L), Ni (0.79 microg/L), and Se (17 microg/L) were at the low end of the corresponding reference ranges. Concentrations of Cr (24.3 microg/L) in human milk were five times higher than the high end of the reference range. For Al (67 microg/L), As (6.7 microg/L), and V (0.18 microg/L), most of the samples had concentrations well within the reference ranges. All elemental concentrations in infant formulas (except for Cr) were approximately one order of magnitude higher than in human milk.

Adult↗

Pleural effusions and sera from patients with benign or malignant diseases.

In pleural effusions and sera from 66 patients copper and zinc were quantified by inductively coupled argon plasma-mass spectrometry after mineralizations in a closed-pressurized microwave unit with a mixture of concentrated nitric acid and 30% hydrogen peroxide. Total protein, pH, leukocyte count, lactate dehydrogenase, glucose, C-reactive protein, ceruloplasmin, and alpha1-antitrypsin were determined in many of the effusions. All but four effusions had concentrations of copper (range 58-1720 microg/kg) and zinc (range 27-1001 microg/kg) that were lower than the concentrations in the corresponding sera. Very high concentrations of zinc (1930-6470 microg/kg) were characteristic for thoracic empyemata. In the scatterplots of serum copper versus effusion copper, serum zinc versus effusion zinc, and serum copper/effusion copper versus serum zinc/effusion zinc no clearly delineated regions were noticeably useful for identifying malignant effusions. Similar plots of the concentrations of copper or zinc versus the eight clinical laboratory parameters or plots of clinical parameter versus clinical parameter failed to be of diagnostic value. Statistically highly significant correlations (p < or = 0.05, n > 45, r2 > 0.25) were observed for 9 of 28 pairs of the clinical parameters, for total protein and copper in the effusions and zinc in the effusions and for ceruloplasmin and copper in the effusions. Among the patients suffering from benign or malignant effusions, 52% had zinc concentrations in the sera below the low limit of the normal range (600 microg/kg). Supplementation of such patients with zinc should be considered.

Adolescent↗

Concentrations of copper, zinc, manganese, rubidium, and magnesium in thoracic empyemata and corresponding sera.

In this study, a number of selected trace elements and clinically relevant parameters were compared between thoracic empyemata and the corresponding sera for a better understanding of the trace element distribution between these two compartments. Serumempyema pairs were obtained from 13 patients and quantified for selected and essential trace elements, namely copper (Cu), zinc (Zn), manganese (Mn), rubidium (Rb), and magnesium (Mg), by inductively coupled plasma-mass spectrometry (ICP-MS). In addition, the concentrations of the following clinical laboratory parameters were analyzed by standard methods: total protein, leukocyte count, lactate dehydrogenase, glucose, pH, and the C-reactive protein. Individual concentrations of the elements determined in the empyemata were frequently higher than in pleural effusions of any other benign or malignant condition except for Cu. Serum Cu exceeded the normal range (600-1400 microg/kg) in 6 out of 13 patients (median 1410 microg/kg). In the empyemata, Zn concentrations (median 2000 microg/kg) were characteristically higher than in the sera (median 450 microg/kg) and exceeded the upper limit for serum (1200 microg/kg) in 8 of the 13 patients. Manganese concentrations in the empyemata (median 2.7 microg/kg) were also higher compared to corresponding sera, although they stayed within the limits considered normal for serum of healthy adults (upper limit 2.9 microg/kg). Rubidium was also moderately higher in most empyemata (median 290 microg/kg) and exceeded the upper limit for serum (560 microg/kg) in two patients. The median concentration of the essential element magnesium was higher in the empyemata (23 mg/kg) than in the sera (21 mg/kg). However, all serum Mg concentrations except three remained within the normal range (17-22 mg/kg). Removal of large amounts of empyematous fluid may deprive the body of trace elements and can cause suboptimal or deficient trace element status and homeostasis. Recuperation will be accelerated by compensatory supplementation of trace elements. Therefore, selective medication with adequate trace element compounds in patients with thoracic empyema can be generally recommended for zinc. The other elements need not necessarily be monitored or substituted, because of their stable concentrations in the serum. Rb may have a biological impact, but deficiency symptoms in man are not clearly defined.

Aged↗

Kinetics of the metal cations magnesium, calcium, copper, zinc, strontium, barium, and lead in chronic hemodialysis patients.

BACKGROUND: Dialysis patients are at risk of developing trace element imbalances. To further elucidate the origin of these potential trace element imbalances, plasma and dialysis fluids concentrations of the elements barium (Ba), calcium (Ca), copper (Cu), lead (Pb), magnesium (Mg), strontium (Sr) and zinc (Zn) of seven maintenance dialysis patients were investigated. PATIENTS AND METHODS: In each hemodialysis session 10 to 15 samples of each, whole blood and dialysis liquid before and after passing the artificial kidney were collected. Concentrations of elements were determined by inductively coupled plasma mass spectrometry following strict quality control schemes to guarantee the accuracy and precision of the results. RESULTS: Plasma concentrations of Cu and Zn continuously increased during hemodialysis. Plasma Cu remained within the reference range for healthy adults, whereas plasma Zn was always at or below the reference range in our patients. The behavior of Ca and Sr exhibited extraordinarily strong similarities both in plasma and dialysis liquids, although concentrations of Sr are approximately 2000 times lower. Plasma Ca and Sr were at or above the upper level of the reference range. Plasma Mg concentrations decreased during clinical treatment, but were at the end of dialysis still more than 50% higher than the high end of the reference range. Although concentrations of Ba in dialysis fluids were approximately 10 times lower than in plasma, plasma Ba concentrations (approximately 23 microg/l) were significantly elevated compared to plasma Ba of healthy adults. Initial concentrations of Pb in plasma (0.74 microg/l) were increased by approximately 15% during the clinical treatment and were always higher than the high limit of the reference range. Dialysis liquids had approximately the same Pb concentrations (0.5 to 1.3 microg/l) as found in the plasma of our patients but with higher concentrations at the inlet of the dialyzer. CONCLUSION: This study could give an insight into the kinetics of trace element concentrations during dialysis, the clinical relevance of which needs to be further elucidated.

Adult↗

Concentrations of trace elements in sera of newborns, young infants, and adults.

Concentrations of trace elements in newborns, infants, and adults may be significantly different from each other. Serum trace element reference ranges for different age groups are of value for diagnostic purposes. Inductively coupled plasma-mass spectrometry was applied to the determination of the 21 trace elements Ba, Be, Bi, Ca, Cd, Co, Cs, Cu, La, Li, Hg, Mg, Mn, Mo, Pb, Rb, Sb, Sn, Sr, TI, and Zn in a total of 117 sera of individuals representing different age groups. After microwave-assisted acid digestion with high-purity reagents, 20 umbilical cord sera, 5 sera of fully breast-fed infants, 6 sera of formula-fed infants, 66 sera of patients suffering internal diseases, and 20 sera of healthy blood donors were analyzed for trace elements. One serum and two whole-blood reference materials were analyzed for quality control. Experimental concentrations were in good agreement with certified values. Umbilical cord serum concentrations of the essential elements Ca, Co, Cu, and Mg and of the nonessential and toxic elements Ba, Be, Li, Pb, and Sb were elevated compared to the elemental concentrations in the sera of infants and adults. Serum levels of Ba, Ca, Co, Mn, Pb, and Sb of infants were much higher and serum Cu was significantly lower than in adults. Serum Cu increased significantly with age (newborns: 353 microg/L; infants: 755 microg/L; healthy adults: 810 microg/L), whereas for other trace elements no age-dependence could be established.

Adult↗

The potential of inductively coupled plasma mass spectrometry (ICP-MS) for the simultaneous determination of trace elements in whole blood, plasma and serum.

The advantages accruing to biochemical and clinical investigations from a method that allows the simultaneous quantification (RSD < or = 10%) of many elements in blood, plasma, and serum at concentrations equal to one-hundredth of the lower limits of the normal ranges are undeniable. The suitability of inductively coupled argon plasma low-resolution quadrupole mass spectrometry (ICP-MS), a simultaneous method with low detection limits, is evaluated for the quantification of inorganic constituents in whole blood, plasma, and serum with consideration of the dilution associated with the mineralization of the samples, of isobaric and polyatomic interferences and of normal ranges. Of the 3 bulk elements, the 3 major electrolytes, the 15 essential elements, the 8 toxic elements, the 4 therapeutic elements, and the 14 elements of potential interest (total of 47 elements) only 7 elements (Ca, Cu, K, Mg, Rb, Sr, Zn) can be simultaneously quantified under these rigorous conditions in serum and only 8 elements (additional element Pb) in whole blood. Quantification of elements in the Seronorm Standards "Whole Blood" and "Serum" showed, that this list of simultaneously determinable elements in these matrices is reasonable. Although this list is disappointingly short, the number of elements determinable simultaneously by ICP-MS is still larger than that by ICP-AES or GFAAS. Improved detectors, more efficient nebulizers, avoidance of interferences, better instrument design, and high-resolution mass spectrometers promise to increase the number of elements that can be determined simultaneously.

Humans↗

Trace element transfer from the mother to the newborn--investigations on triplets of colostrum, maternal and umbilical cord sera.

OBJECTIVE: To investigate the trace element transfer from the mother to the newborn. DESIGN: The concentrations of the eight essential elements calcium (Ca), cobalt (Co), copper (Cu), magnesium (Mg), manganese (Mn), molybdenum (Mo), tin (Sn), and zinc (Zn), and of the non-essential and toxic elements barium (Ba), beryllium (Be), bismuth (Bi), cadmium (Cd), cesium (Cs), lanthanum (La), lithium (Li), lead (Pb), rubidium (Rb), antimony (Sb), strontium (Sr), and thallium (Tl) were determined in umbilical cord (n = 29) and corresponding maternal sera (n = 29) as well as in colostrum (n = 27). RESULTS: Umbilical cord serum concentrations of Ca, Mn, and Zn were 120%, 150%, and 148% of the maternal value, respectively. Maternal sera had twice the Cu concentrations found in healthy adults and five-times higher Cu than umbilical cord sera. Concentration ratios colostrum/maternal serum and colostrum/umbilical cord serum were approximately one for Co, 1.4 for Mg, two for Ca, Mn, and Sn, five for Cu (maternal serum), eight for Mo, and ten for Zn. Concentrations of the toxic elements Cd and Pb decreased in the order colostrum (Pb 2.6 microg/L; Cd 0.6 microg/L), maternal sera (0.8 microg/L; 0.3 microg/L), umbilical cord sera (0.4 microg/L; 0.2 microg/L). Maternal serum Ba and Rb was 182% and 66% of the umbilical cord value. For Sr and Li, an almost perfect correlation between umbilical cord and maternal sera was found. For Ba, Co, Cu, Mn, Zn none, and for Ca, Cs, Mn, Mo, Rb only weak positive correlations between these two compartments could be established. CONCLUSIONS: The results of this study indicate that an active transport mechanism for the transport of Ca, Mn, Rb, and Zn from the mother to the newborn exists, whereas Cs, Li, and Sr follow concentration gradients. As regards Cu, the placenta showed to have a blocking effect on the transfer from the mother to the baby.

Adult↗

Optimized procedure for the determination of antimony in lipid-rich environmental matrices by flow injection hydride generation atomic absorption spectrometry.

An analytical procedure for the reliable determination of Sb in digests of lipid-rich environmental matrices in the low ng l-1-range based on flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) has been developed. Prior to HG-AAS, aliquots (250 to 320 mg) of dry samples were mineralized with 3 ml nitric acid and 0.5 ml of each sulfuric and perchloric acids in open digestion vessels made of glassy carbon in a heating block. Procedure detection and quantification limits of a previously developed procedure for the determination of Sb in plant materials by FI-HG-AAS were decreased with respect to the lower Sb concentrations in animal tissues, the sensitivity of the instrumental response was increased, and the composition of the acid digestion mixture was re-optimized for lipid-rich samples. The accuracy and precision of the developed procedure was evaluated by the analysis of the two reference materials Bovine Liver 1577a and Pig Kidney CRM 186. These reference materials have been additionally spiked with appropriate amounts of Sb to obtain recovery data. The solution detection limit (3 sigma) in digested samples was 0.021 microgram l-1, the detection limit for the whole procedure based on the dry powders was 7 pg g-1, the method quantification limit for a reliable determination of Sb was 23 pg g-1. The reproducibility of repetitive measurements was 6.0% at 0.1 microgram Sb l-1 and 2.2% at 0.5 microgram Sb l-1. Calibration curves were linear from 0.05 to 3 micrograms Sb l-1. To demonstrate the suitability of the developed method, concentrations of Sb have been determined in pigeon eggs (approximately 2 ng Sb g-1), as well as in bream livers (approximately 4 ng g-1) and in deer livers (approximately 5 to 8 ng g-1) from animals living in remote and urban-industrialized areas of Germany, respectively.

Animals↗

Biomonitoring of antimony in environmental matrices from terrestrial and limnic ecosystems.

Elder and poplar leaves from various sampling sites were studied with respect to their antimony content. Moreover, a retrospective determination of Sb was performed in representative limnic and terrestrial samples of the Federal Environmental Specimen Bank of Germany which have been collected over 14 years. The analytical procedure is based on an open vessel acid digestion of freeze-dried biological samples and the subsequent quantification of Sb in the digests by flow injection hydride generation atomic absorption spectrometry. Strict quality control schemes were applied to the entire procedure to guarantee accurate and precise results. No long-term changes of the Sb concentrations were found in spruce shoots or poplar leaves from different sampling sites. However, spruce shoots from a semi-natural region showed concentrations of Sb (approximately 22 ng g-1; range: 17-29 ng g-1) that were approximately four times lower than in corresponding samples from an urban-industrialized area. The analysis of virgin and washed elder leaves revealed that approximately 20-30% of the Sb is present on the leaf surface. Sb levels in elder leaves ranged from 5.2 +/- 0.3 ng g-1 in samples from Argentina to 589 +/- 30 ng g-1 in leaves collected directly beside a motorway in Germany. Similarly, poplar leaves from Argentina and Chile showed about 4 ng Sb g-1, whereas 150 ng Sb g-1 was found in poplar leaves from Germany. The lowest concentrations of Sb were determined in digests of pigeon eggs (approximately 2 ng g-1), bream liver (approximately 4 ng g-1) and deer liver (approximately 6 ng g-1). A similar pattern of Sb concentrations in spruce shoots, leaves or liver samples from an industrialized area and an agrarian ecosystem in Germany was established. Concentrations of Sb in elder leaves were closely associated with car traffic, giving maximum concentrations of 589 ng g-1 directly beside a motorway, 207 ng g-1 50 m from the motorway and 153 ng g-1 in a close residential area.

Agriculture↗