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Bernd Seifert

Publications and source records attributed to Bernd Seifert.

5 recordsLinked to original sources

GerES IV pilot study: assessment of the exposure of German children to organophosphorus and pyrethroid pesticides.

Organophosphorus pesticides and pyrethroids are widely used in German agriculture and residential settings. Their occurrence in human biological samples can be used as an indicator for the exposure of children to these compounds. Using multivariate evaluation the routes of exposure can be identified. In the pilot study of GerES IV, metabolites of pyrethroids and organophosporus pesticides were analysed in urine of children aged 2-17 years (n = 396 and 363). The 95th percentiles for the metabolites of the pyrethroids in urine were: cis-DCCA 0.74 microg/l, trans-DCCA 1.7 microg/l, DBCA 0.52 microg/l, F-PBA < 0.1 microg/l, and 3-PBA 2.4 microg/l. 3-PBA was detected in 90% of the samples. The 95th percentiles for the organophosphorus metabolites in urine were: DMP 118 microg/l, DEP 20 microg/l, DMTP 124 microg/l, DETP 11 microg/l, DMDTP 11 microg/l, DEDTP < 1.0microg/l. DMTP was the metabolite most frequently detected in the samples (90%). Based on the metabolites analysed in urine the exposure to organophosphorus pesticides is mainly influenced by age, consumption of fresh fruits and fruit juice, living in an urban area, and season. A rough estimation revealed that the ADI values for organophosphorus pesticides might be exceeded. However, these results require further exploration. The exposure to pyrethroids is influenced by age, sampling location, consumption of boiled vegetables, and the use of biocides indoors at home. In addition, a significant correlation between permethrin in house dust and the metabolite concentrations in urine could be observed. Thus it seems likely that ingestion of house dust contributes to children's exposure.

Adolescent↗

DEHP metabolites in urine of children and DEHP in house dust.

Urine samples from the 2001/2002 pilot study for the German Environmental Survey on children (GerES IV) were analysed for concentrations of the primary DEHP metabolite MEHP (mono(2-ethylhexyl)phthalate) and two secondary DEHP metabolites SOH-MEHP (2-ethyl-5-hydroxy-hexylphthalate) and 5oxo-MEHP (2-ethyl-5-oxo-hexylphthalate). Urine samples had been taken from 254 children aged 3 to 14. In addition, DEHP was analysed in house dust samples. These samples had been collected with vacuum cleaners in the homes of the children. The geometric mean (GM) was 7.9 microg/l for MEHP in urine, and the GMs for the secondary metabolites 5OH-MEHP and 5oxo-MEHP were 52.1 microg/l and 39.9 microg/l. 5OH-MEHP and 5oxo-MEHP concentrations were highly correlated (r = 0.98). The correlations of 5OH-MEHP and 5oxo-MEHP with MEHP were also high (r = 0.72 and r = 0.70). The concentrations of 5OH-MEHP and 5oxo-MEHP were 8.0-fold and 6.2-fold higher than the concentrations of MEHP. The ratios 5OH-MEHP/Soxo-MEHP and 5oxo-MEHP/MEHP decreased with increasing age. Boys showed higher concentrations than girls for all three metabolites of DEHP in urine. Children aged 13-14 had the lowest mean concentrations of the secondary metabolites in urine. The house dust analyses revealed DEHP contamination of all samples. The GM was 508 mg/kg dust. No correlation could be observed between the levels of any of the urinary DEHP metabolites and those of DEHP in house dust.

Adolescent↗

German Environmental Survey 1998 (GerES III): environmental pollutants in the urine of the German population.

The German Environmental Survey (GerES) is a cross-sectional probability study to determine the exposure of the general population to environmental contaminants. The study was repeated for the third time in 1998 (GerES III). Again, a stratified random procedure was used to select the study population taking into account the parameters gender, age, community size and place of residence (West- or East-Germany). A total of 4822 persons between 18 and 69 years of age from 120 localities participated in GerES III. Human biomonitoring comprised the determination of arsenic, cadmium, mercury, metabolites of polycyclic aromatic hydrocarbons (PAH), pentachlorophenol (PCP), other chlorophenols, precious metals (gold, platinum, iridium), nicotine, and cotinine in urine.

Adolescent↗

German Environmental Survey 1998 (GerES III): environmental pollutants in blood of the German population.

The German Environmental Survey was conducted for the third time in 1998 (GerES III). The probability sample of about 4800 subjects was selected to be representative for the German population with regard to region (East-/West-Germany), community size, age (18 to 69 years) and gender. Blood samples were taken from each study participant and questionnaires were used to get exposure-related information. Cadmium, lead, mercury, hexachlorobenzene (HCB), hexachlorocyclohexane (alpha-HCH, beta-HCH, gamma-HCH), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p, p'-DDE) and polychlorinated biphenyls (PCB-138, PCB-153, PCB-180) were analysed in whole blood to document the extent, distribution, and determinants of exposure of the general population to these substances. The geometric means of Cd, Pb, and Hg in blood amounted to 0.44, 31, and 0.58 microgram/l, respectively. Smokers showed a Cadmium level of 1.1 micrograms/l and non-smokers a level of 0.28 microgram/l. The geometric mean of lead was higher in the blood of males than of females (36 micrograms/l vs. 26 micrograms/l). The concentration of mercury in blood depends on fish consumption and the number of teeth with amalgam fillings. The mean concentrations of HCB and p, p'-DDE in blood were 0.44 microgram/l and 1.6 micrograms/l, respectively. In East-Germany (the former GDR) the DDE concentration in blood was more than twice as high as in West-Germany. Geometric means for PCB were 0.42, 0.68 and 0.44 microgram/l for PCB-138, PCB-153, and PCB-180, respectively. A marked increase of HCB, DDE and PCB levels with age could be observed. alpha-HCH and gamma-HCH could be detected in 1.7% and 5.2% of the samples only. beta-HCH was quantified in 34% of the samples with a 95th percentile of 0.5 microgram/l.

Adolescent↗