Publications (52)76.22 Total impact
- [Show abstract] [Hide abstract] ABSTRACT: Veröffentlicht in der Reihe Analytische Methoden zur Prüfung gesundheitsschädlicher Arbeitsstoffe: Analysen in biologischem Material, 14. Lieferung, Ausgabe 2000Der Artikel enthält folgende Kapitel:Grundlage des VerfahrensGeräte, Chemikalien und LösungenGeräteChemikalienLösungenVergleichsstandardsProbenahme und ProbenaufbereitungInstrumentelle ArbeitsbedingungenFlüssigchromatographische ArbeitsbedingungenFließinjektionssystem-ArbeitsbedingungenAtomabsorptionsspektrometrische ArbeitsbedingungenPrinzip des HPLC-VerfahrensAnalytische BestimmungKalibrierungBerechnung der AnalysenergebnisseStandardisierung der Messergebnisse und QualitätssicherungBeurteilung des VerfahrensPräzisionRichtigkeitNachweisgrenzenStöreinflüsseDiskussion der MethodeKeywords:Bestimmung im Urin;Flüssigchromatographie;Hydrid-AAS;Analyse in biologischem Material;Biomarker;Metabolite;Analysenmethoden
- [Show abstract] [Hide abstract] ABSTRACT: Nickel is one of the most prevalent causes of contact allergy in the general population. This study focuses on human exposure to airborne nickel and its potential to induce allergic sensitization. The study group consisted of 309 children at school-starter age living in the West of Germany in the vicinity of two industrial sources and in a rural town without nearby point sources of nickel. An exposure assessment of nickel in ambient air was available for children in the Ruhr district using routinely monitored ambient air quality data and dispersion modelling. Internal nickel exposure was assessed by nickel concentrations in morning urine samples of the children. The observed nickel sensitization prevalence rates varied between 12.6% and 30.7%. Statistically significant associations were showed between exposure to nickel in ambient air and urinary nickel concentration as well as between urinary nickel concentration and nickel sensitization. Furthermore, an elevated prevalence of nickel sensitization was associated with exposure to increased nickel concentrations in ambient air. The observed associations support the assumption that inhaled nickel in ambient air might be a risk factor for nickel sensitization; further studies in larger collectives are necessary.
- [Show abstract] [Hide abstract] ABSTRACT: Warum Elementspeziesanalytik?Anwendungsgebiete der ElementspeziesanalytikStrategien der ElementspeziesanalytikProbennahme, Probenlagerung, Probenvorbereitung und VerbundverfahrenBewertung, Validierung und Interpretation von ESA-Daten
- [Show abstract] [Hide abstract] ABSTRACT: Definition der KopplungstechnikenTrennmodulDetektormodulInterfaceQuantitative AuswertungFlüssigkeitschromatographische Trennmethoden (LC)Gaschromatographische Trennmethoden und Chromatographie mit überkritischen FluidenElektrophoretische TrennmethodenSonstige KopplungstechnikenBewertung der Analysendaten
- [Show abstract] [Hide abstract] ABSTRACT: Aluminium (Al)Arsen (As)Cadmium (Cd)Chrom (Cr)Kupfer (Cu)Eisen (Fe)Quecksilber (Hg)Nickel (Ni)Blei (Pb)Selen (Se)Zinn (Sn)Zink (Zn)Sonstige Metalle
- [Show abstract] [Hide abstract] ABSTRACT: Kopplungstechniken;Elementspeziesanalytik;Kombination Trenn- und Detektionsmethoden
- [Show abstract] [Hide abstract] ABSTRACT: Mehrdimensionale TrenntechnikenNachweisstarke MultielementmethodenDetektion von Bindungspartnern und GesamtspeziesProbennahme und ProbenvorbereitungQuantifizierung von Daten aus KopplungstechnikenNeue Fragestellungen
- [Show abstract] [Hide abstract] ABSTRACT: Cadmium (Cd) and lead (Pb) exposure of children and their mothers living in the vicinity of industrial sources (metal refining) was assessed by a cross-sectional study performed in 2000. Study areas were the highly industrialized city of Duisburg and a rural area of North Rhine Westphalia, Germany. Exposure to ambient air concentrations of Cd and Pb was calculated from a Lagrange dispersion model using data sets from ambient air quality measurements. Cd in blood and urine and Pb in blood were measured by AAS. Mean age (years) was 6.4 (range 5.5-7.7) for children (n = 238) and 36 (range 23-48) for mothers (n = 213). A total of 49% of the children were males. Factors suspected to influence metal levels in blood or urine were obtained by questionnaire. Individual ambient Cd and Pb levels according to the home address ranged from 0.5 ng/m3 (Cd) and 0.03 microg/m3 (Pb) (rural area) up to 31.2 ng/m3 (Cd) and 0.73 microg/m3 (Pb) (industrialized area). Cd levels (geometric mean) in blood (0.13 and 0.10 microg/L) and urine (both areas 0.09 microg/L) of children did not differ between the two areas. Cd levels in blood and urine of mothers from the industrialized area were higher (blood 0.39 microg/L, urine 0.28 microg/L) than in those from the rural area (blood 0.25 microg/L, urine 0.25 microg/L). Pb levels in the blood of children from the industrialized area were higher (31 microg/L) than in those from the rural area (21 microg/L). Pb levels in the blood of mothers did not differ between the two areas (both 24 microg/L). Pb levels in blood showed a significant association between child and mother (n = 192; r = 0.26, p < 0.001). This did not apply for Cd in blood or urine. Regression analysis clearly revealed that Pb levels in ambient air were associated with Pb in the blood of children. Minor associations were also found between Cd in air and Cd in the blood of mothers and between Cd in air and urine of mothers.
- [Show abstract] [Hide abstract] ABSTRACT: Platinum (Pt) is a well-known constituent of particles emitted by catalytic converters during car operation. To evaluate Pt as a potential marker for traffic related particle exposure, we investigated Pt content along with metals vanadium (V) and chromium (Cr) in coarse and fine particulate matter (PM), sampled in four areas with different traffic density, as well as in the nasal lavage (NAL) of 67 children (average age: 6 years) living in these areas. The different sites were characterised by significant differences in air pollutants including PM, NO, NO(2), CO and Cr, but differences in V or Pt were absent. No significant differences in neutrophil and epithelial cell counts or concentrations of the neutrophil chemoattractant interleukin-8 (IL-8) were found in the NAL of children living in the different areas. In addition, the concentrations of V, Cr and Pt, which were detectable in 64%, 73% and 93% of the individuals, respectively, did not differ between the different locations. However, in the NAL of the children, a significant correlation between Pt and the number of neutrophils/ml (r=0.40, p<0.001) as well as of epithelial cells/ml (r=0.41, p<0.001) was found. No relation was present between nasal inflammation and nasal Cr levels, whereas a relatively weak association was observed between V and epithelial cells counts (r=0.30, p=0.018). In conclusion, our data suggests a role for nasal lavage Pt as a candidate biomarker for traffic-related PM, which is able to induce inflammation in the upper respiratory tract.
- [Show abstract] [Hide abstract] ABSTRACT: The dietary intake of platinum and gold by 84 small children, 42 boys and 42 girls at the age of 14 to 83 months, with different food consumption behaviour living in urban and rural areas of Germany was measured by the duplicate method with a seven day sampling period from May to September 1998. The levels in the food duplicates were in the range of < 0.01 to 450 ng Pt/kg (dry weight) (median: 22) and < 0.14 to 28 microg Au/kg (dry weight) (median: 0.645). Related to the body weight, Pt was in the range of < 0.81 to 32 ng/(kg (body weight) x week) (median: 2.3) and Au was < 0.015 to 2.6 microg/(kg (body weight) x week) (median: 0.068). Children consuming exclusively products from the super market showed slightly higher Pt concentrations in the food duplicates and a higher dietary intake per body weight than children with food consumption including products from the family owned vegetable gardens or the surrounding area and/or products from domestic animals of the surrounding area. No influence of the food consumption behaviour was found for the concentrations in the food duplicates or the dietary intake of Au.
- [Show abstract] [Hide abstract] ABSTRACT: Eine neuartige Kopplungstechnik für die Bestimmung von Hintergrundkonzentrationen an Trimethylarsinoxid (TMAO) und anderen Metaboliten des Arsens im menschlichen Urin wurde entwickelt. Die Ergebnisse liefern neue Einblicke in den Arsen-Metabolismus im menschlichen Organismus bei umweltbedingter Arsen-Exposition. A novel coupling technique for the determination of trimethylarsine oxide (TMAO) and other arsenic metabolites has been developed and validated in order to determine background levels of TMAO in human urine. The results provide new insights in metabolic pathways in man at environmental exposure levels.
- [Show abstract] [Hide abstract] ABSTRACT: To determine the induction of 8-hydroxy-2'-deoxyguanosine (8-OHdG) by fine (<2.5 microm) and coarse (10-2.5 microm) particulate matter (PM) sampled over time at one sampling location, and to relate the observed effects to the hydroxyl radical (*OH) generating activities and transition metal content of these samples, and to meteorological parameters. Weekly samples of coarse and fine PM were analysed for H(2)O(2) dependent *OH formation using electron spin resonance (ESR) and formation of 8-OHdG in calf thymus DNA using an immuno-dotblot assay. Immunocytochemistry was used to determine 8-OHdG formation in A549 human epithelial lung cells. To determine temporal effects, samples from six weeks in summer and six weeks in autumn/winter were compared using ESR and the dotblot assay. Concentrations of leachable V, Cr, Fe, Ni, and Cu were determined by inductively coupled plasma mass spectrometry. Both PM fractions elicited *OH generation as well as 8-OHdG formation in calf thymus DNA and in A549 cells. 8-OHdG formation in the naked DNA was significantly related to *OH generation, but not to metal concentrations except for copper. A significantly higher *OH generation was observed for coarse PM, but not fine PM collected during the autumn/winter season; this was not due to differences in sampled mass or metal content. Specific weather conditions under which increased *OH formation in the coarse mode was observed suggest that other, as yet unknown, anthropogenic components might affect the radical generating capacity of PM. Both coarse and fine PM are able to generate *OH, and induce formation of 8-OHdG. When considered at equal mass, *OH formation shows considerable variability with regard to the fraction of PM, as well as the sampling season. The toxicological implications of this heterogeneity in *OH formation by PM, as can be easily determined by ESR, need further investigation.
- [Show abstract] [Hide abstract] ABSTRACT: A field study was performed to assess the internal exposure of 149 five- to seven-year old children to traffic-related pollutants. The study was carried out in areas with high and low traffic density located in Western Germany (Essen/Ruhr, Borken, Northrhine-Westphalia) and Eastern Germany (Halle/Saale, Osterburg, Saxony-Anhalt). The benzene, toluene, o-,m-,p-xylene (BTX) concentrations in blood and the platinum excretion in urine served as markers for a traffic-related exposure. The parents were asked to answer a questionaire, which asked for such information as traffic density in the vicinity of the dwelling, redecoration activities inside the rooms, exposure to solvent containing household products, passive smoking, etc. The results of this study show, that emissions from traffic have a significant influence on the internal BTX burden of children. The internal benzene exposure is mainly a result of the benzene concentration in outdoor air, which as a result of the absence of indoor sources is reflected in indoor air. Regarding toluene and xylene indoor air concentrations were generally higher than those outdoors indicating that several relevant indoor sources exist. The urinary platinum (Pt) excretion of the children from both high traffic areas (Essen/Ruhr, Halle/Saale) tended to higher values when compared with the Pt excretion of those children from the low-traffic areas. However, this differences were statistically not significant. The results of this study do not definitively prove whether emissions from automobile catalysts are responsible for the slightly higher Pt exposure of these children.
- [Show abstract] [Hide abstract] ABSTRACT: Lead contents in hair, whole blood and saliva were determined for 245 healthy children (121 male, 124 female, age: 8-10 years) from three residential areas of Düsseldorf (North-Rhine-Westphalia, Germany) with different traffic densities. The geometric mean for the lead content in hair was found to be 0.87 microg/g (range: 0.2-9.9 microg/g) for the entire test group. While the levels of lead in hair in the suburban population were significantly lower than in the two city centre populations, no significant difference concerning the lead content in hair could be detected in the latter. The geometric mean for lead concentration in whole blood amounted to 25.0 microg/l (range: 8.0-154 microg/l). There was no significant difference between the sub-groups. The lead concentrations found in saliva were rather low (range: < 1.5-47.0 microg/l). Of the values, 89% were below the detection limit of 1.5 microg/l. Due to reduced levels of lead in fuel, the present study exposes that the amount of lead in the children examined has further decreased compared to preceding surveys. The correlation between the lead content in hair and the road traffic density was not corroborated by the findings with regard to amounts of lead found in blood, indicating that residual lead from fuel does not result in a substantial burden of lead found in the whole body. In contrast to levels of lead found in blood, levels of lead found in hair may be influenced more by environmental conditions. Saliva is not a suitable material for biological monitoring with respect to lead exposure in children.
- [Show abstract] [Hide abstract] ABSTRACT: We adapted our mouse model of allergic contact hypersensitivity to nickel for the study of tolerance. Sensitization in this model is achieved by the administration of nickel ions with H(2)O(2); nickel ions alone are unable to prime naive T cells, but can restimulate primed ones. A 4-wk course of oral or i.p. administration of 10 mM NiCl(2) to naive mice induced tolerance, preventing the induction of hypersensitivity for at least 20 wk; long term desensitization of nickel-sensitized mice, however, required continuous NiCl(2) administration. When splenic T cells of orally tolerized donors, even after a treatment-free interval of 20 wk, were transferred to naive recipients, as with lymph node cells (LNC), they specifically prevented sensitization of the recipients. The LNC of such donors were anergic, because upon in vivo sensitization with NiCl(2) in H(2)O(2) and in vitro restimulation with NiCl(2), they failed to show the enhanced proliferation and IL-2 production as seen with LNC of mice not tolerized before sensitization. As few as 10(2) bulk T cells, consisting of both CD4(+) and CD8(+) cells, were able to specifically transfer tolerance to nickel. A hypothesis is provided to account for this extraordinarily high frequency of nickel-reactive, suppressive T cells; it takes into account that nickel ions fail to act as classical haptens, but form versatile, unstable metal-protein and metal-peptide complexes. Furthermore, a powerful amplification mechanism, such as infectious tolerance, must operate which allows but a few donor T cells to tolerize the recipient.
- [Show abstract] [Hide abstract] ABSTRACT: Urinary levels of hydride-forming arsenic species were measured in 367 school-children living in the surrounding of Augsburg, Germany. Additionally, all urine samples with a concentration of hydride-forming arsenic species above 15 μg/l were analysed for arsenobetaine to look for a possible consumption of fish. In 350 of 367 urine samples (95%) the concentration of hydride-forming arsenic species was found to be below 15 μg/l. The concentrations ranged between 1.0 and 32.8 μg/l with a geometric mean of 6.0 μg/l. In those17 urine samples with levels of hydride forming species above 15 μg/l the arsenobetaine concentrations ranged between < 0.5 μg/l to 1750 μg/l. In 8 out of these 17 samples arsenobetaine was found in detectable concentrations. In these cases the elevated levels of toxic arsenic species are caused by seafood consumption. In the remaining 9 cases an environmental exposure to inorganic arsenic cannot be excluded.
- [Show abstract] [Hide abstract] ABSTRACT: Six aromatic hydrocarbons (benzene, toluene, ethylbenzene and the three isomeric xylenes) were monitored in the indoor and outdoor air of 115 private non-smoker homes (∼380 rooms), about half of which were located in two city streets in Hannover (Northern Germany) with high traffic density, the other half in rural areas with hardly any traffic at all. This environmental monitoring was complemented by human biomonitoring (i.e. the determination of aromatic hydrocarbons in blood and exhaled air). Particular attention was paid to benzene as a result of its carcinogenicity. In the city streets with high traffic density, an average benzene concentration of 3.1 μg m−3 and in the rural areas of 1.8 μg m−3 was found in these non-smoker homes (all data=geometric means), which reflects the influence of the traffic (automobile exhaust) on the benzene level found indoors. Source identification is also possible by determining the indoor/outdoor (I/O) concentration ratio. For the rooms facing the city street, this I/O ratio is close to 1 for all aromatic hydrocarbons studied with the exception of toluene (I/O=3.5), while in the rural areas I/O ratios for the individual compounds ranging in 6–9 were determined, with the exception of benzene where the I/O ratio is only 1.5. These I/O ratios in the city street with high traffic density indicate that an equilibrium between indoor and outdoor air is almost reached. Indoor sources prevail only in the case of toluene. In contrast, in the rural area, indoor sources dominate for all aromatic hydrocarbons except benzene, the indoor level of which is mainly influenced by the outdoor air even in areas of very low traffic density. However, weak indoor sources must exist also for this compound even in non-smoker homes. The internal exposure of the non-smoking inhabitants of these homes to benzene is very low. Depending on the living area, mean values of 61–67 ng l−1 benzene in blood and 0.9–1.2 μg m−3 in the exhaled air were found.
- [Show abstract] [Hide abstract] ABSTRACT: Methods for the determination of 3,4-dichloroaniline (3,4-DCA) and 3,5-dichloroaniline (3,5-DCA) as common markers of eight non-persistent pesticides in human urine are presented. 3,5-DCA is a marker for the exposure to the fungicides vinclozolin, procymidone, iprodione, and chlozolinate. Furthermore the herbicides diuron, linuron, neburon, and propanil are covered using their common marker 3,4-DCA. The urine samples were treated by basic hydrolysis to degrade all pesticides, metabolites, and their conjugates containing the intact moieties completely to the corresponding dichloroanilines. After addition of the internal standard 4-chloro-2-methylaniline, simultaneous steam distillation extraction (SDE) followed by liquid-liquid extraction (LLE) was carried out to produce, concentrate and purify the dichloroaniline moieties. Gas chromatography (GC) with mass spectrometric (MS) and tandem mass spectrometric (MS-MS) detection and also detection with an electron-capture detector (ECD) after derivatisation with heptafluorobutyric anhydride (HFBA) were employed for separation, detection, and identification. Limit of detection of the GC-MS-MS and the GC-ECD methods was 0.03 and 0.05 microg/l, respectively. Absolute recoveries obtained from a urine sample spiked with the internal standard, 3,5-, and 3,4-DCA, ranged from 93 to 103% with 9-18% coefficient of variation. The three detection techniques were compared concerning their performance, expenditure and suitability for their application in human biomonitoring studies. The described procedure has been successfully applied for the determination of 3,4- and 3,5-DCA in the urine of nonoccupationally exposed volunteers. The 3,4-DCA levels in these urine samples ranged between 0.13 and 0.34 microg/g creatinine or 0.11 and 0.56 microg/l, while those for 3,5-DCA were between 0.39 and 3.33 microg/g creatinine or 0.17 and 1.17 microg/l.
Düsseldorf, North Rhine-Westphalia, Germany
- Institute of Environmental Health Research at the HHU
Robert Schumann Hochschule DüsseldorfDüsseldorf, North Rhine-Westphalia, Germany