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Natural Radionuclides in Groundwater (NORM) (WMS)

Considering water as the primary resource necessary for social life, agriculture, industry, and wealth, the importance of groundwater investigation is clear. Apart from many other pollutants, this work focusses on geogenic uranium (U) and radium (Ra), which both stand for natural radionuclides (NORM) that need to be considered frame of groundwater exploration and monitoring programmes due to their specific mobility and chemo-/radiotoxicity. As investigation of U and – to a lesser extent - Ra is done by an increasing number of scientific working groups, the global dataset is improving continuously. In order to give a summarized overview on available and recent literature, scientific papers, reports, and governmental documents have been reviewed for U-238 mass concentrations and Ra-226 and Ra-228 activity concentrations and collected in tables and global maps. Further natural isotopes of U and Ra have been rarely subject of investigation. The collected data were evaluated and interpreted in frame of an associated scientific publication (see citation). From the available data it can be concluded that high geogenic U occur mainly under oxidizing conditions and carbonate rich groundwater, which might be seen as indicator for elevated U concentrations. Certain geological formations, as for example sedimentary, granitic, and volcanic host rocks, promote high U concentrations in groundwater. For geogenic Ra, the search for definite indications proved difficult, since less clear correlation is given for any observed factor. In a global perspective, the most promising evidence for elevated Ra are highly reducing redox conditions, as well as the occurrence of Fe/Mn mineral phases. Furthermore, barite represents a sink for Ra due to its ability to incorporate Ra isotopes. Dissolution of those mineral phases eventually results in co-dissolution of Ra, when Ra is found in host rocks of investigated aquifers, or downstream of such groundwater reservoirs. Furthermore, cation exchange might enhance Ra mobility process, especially in case of sedimentary aquifers with low sorption capacity and/or aquifers with high salinity. Given those chemical requirements for the occurrence of U and Ra, a negative correlation between mother and daughter nuclide can be established. When knowledge on present geological and geochemical constraints is available, elevated U and Ra concentrations might be predictable, as long as anthropogenic influence is excluded.

Biogenic and fossil carbon in sewage sludge and digester gas determined by isotope investigation

The aim of the study was to conduct an initial analytical survey of a small number of samples analyze the proportion of fossil carbon in sewage sludge and digester gas and to correlate it with other data collected in a sewage treatment plant. A conservative but representative standard value of 80% biogenic carbon could be derived for sewage treatment plants if they receive less than half of the load from commercial sources – despite continued significant fluctuations. This value, which corresponds to a value derived from Article 31 (1 c) MRR can be used as a standard value for sewage sludge and digester gas from sewage treatment plants with predominantly municipal wastewater. Veröffentlicht in Texte | 150/2022.

Stable carbon isotope ratios of tree-ring cellulose from the site network of the EU-Project ‘ISONET’

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Parabens in 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

Moos, Rebecca K.; Koch, Holger M.; Angerer, Jürgen; Apel, Petra; Schröter-Kermani, Christa; Brüning, Thomas; Kolossa-Gehring, Marike International Journal of Hygiene and Environmental Health 218 (2015), 7, 666-674 Parabens are widely used as antimicrobial preservatives in personal care and consumer products, food and pharmaceuticals. Due to their ubiquity, humans are constantly exposed to these chemicals. We assessed exposure to nine parabens (methyl-, ethyl-, n- and iso-propyl-, n- and iso-butyl-, benzyl-, pentyl- and heptyl paraben) in the German population from 1995 to 2012 based on 660 24 h urine samples from the German Environmental Specimen Bank (ESB) using on-line HPLC coupled to isotope dilution tandem mass spectrometry. The limit of quantification (LOQ) was 0.5 μg/L for all parabens. We detected methyl-, ethyl- and n-propyl paraben in 79–99% of samples, followed by n-butyl paraben in 40% of samples. We infrequently detected iso-butyl-, iso-propyl- and benzyl paraben in 24%, 4% and 1.4% of samples, respectively. Urinary concentrations were highest for methyl paraben (median 39.8 μg/L; 95th percentile 319 μg/L) followed by n-propyl paraben (4.8 μg/L; 95th percentile 74.0 μg/L) and ethyl paraben (2.1 μg/L; 95th percentile 39.1 μg/L). Women had significantly higher urinary levels for all parabens than men, except for benzyl paraben. Samples from the ESB revealed that over the investigation period of nearly 20 years urinary paraben levels remained surprisingly constant; only methyl paraben had a significant increase, for both men and women. We found strong correlations between methyl- and n-propyl paraben and between n- and iso-butyl paraben. These results indicate that parabens are used in combination and arise from common sources of exposure. Urinary excretion factors are needed to extrapolate from individual urinary concentrations to actual doses. doi:10.1016/j.ijheh.2015.07.005 Verwandte Publikation: Daily intake and hazard index of parabens based upon 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

Stable oxygen isotope ratios of tree-ring cellulose from the site network of the EU-Project ‘ISONET’

Abstract

Metabolites of the alkyl pyrrolidone solvents NMP and NEP in 24-h urine samples of the German Environmental Specimen Bank from 1991 to 2014

Ulrich, Nadin; Bury, Daniel; Koch, Holger M.; Rüther, Maria; Weber, Till; Käfferlein, Heiko-Udo; Weiss, Tobias; Brüning, Thomas; Kolossa-Gehring, Marike Int Arch Occup Environ Health (2018); online 22. August 2018 The aim of this study was to get a first overview of the exposure to the solvents and reproductive toxicants N-methyl-2-pyrrolidone (NMP) and N-ethyl-2-pyrrolidone (NEP) in Germany. NMP and NEP metabolite concentrations were determined in 540 24-h urine samples of the German Environmental Specimen Bank collected from 1991 to 2014. With these data we were able to investigate NMP/NEP exposures over time and to evaluate associated risks. NMP metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) and NEP metabolites 5-hydroxy-N-ethyl-2-pyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI) were determined by stable isotope dilution analysis using solid phase extraction followed by derivatization (silylation) and GC-EI-MS/MS. We were able to quantify 5-HNMP and 2-HMSI in 98.0 and 99.6% and 5-HNEP and 2-HESI in 34.8 and 75.7% of the samples. Metabolite concentrations were rather steady over the timeframe investigated, even for NEP which has been introduced as an NMP substitute only in the last decade. Calculated median daily intakes in 2014 were 2.7 µg/kg bw/day for NMP and 1.1 µg/kg bw/day for NEP. For the combined risk assessment of NMP and NEP exposure, the hazard index based on the human biomonitoring assessment I values (HBM I values) was less than 0.1. Based on the investigated subpopulation of the German population, individual and combined NMP and NEP exposures were within acceptable ranges in the investigated timeframe. Sources of NEP exposure in the 90s and 00s remain elusive. doi:10.1007/s00420-018-1347-y

Chemical and Isotopic Composition of Gas in Salt Beds of a Potash Mine

Abstract

Entering markets and bodies: increasing levels of the novel plasticizer Hexamoll® DINCH® in 24 hr urine samples from the German Environmental Specimen Bank

Schütze, André; Kolossa-Gehring, Marike; Apel, Petra; Brüning, Thomas; Koch, Holger M. International Journal of Hygiene and Environmental Health (2013), online 16. August 2013 DINCH (diisononylcyclohexane-1,2-dicarboxylate) was introduced into the world market in 2002 as a non-aromatic plasticizer and phthalate substitute. We analyzed 300 urine samples (24 h voids) of the German Environmental Specimen Bank (ESB for Human tissues, ESB Hum) for specific DINCH metabolites by on-line HPLC-MS/MS with isotope dilution quantification. Urine samples of the ESB Hum were from the years 1999, 2003, 2006, 2009 and 2012, chosen to investigate the appearance and a possible trend of DINCH exposure since its market introduction. No DINCH metabolites were detected in the 1999 and 2003 samples. From 2006 on, the percentage of samples with DINCH metabolites above the LOQ increased significantly over the years (7% in 2006, 43% in 2009 and 98% in 2012). The cyclohexane-1,2-dicarboxylic acid-mono(hydroxy-isononyl) ester (OH-MINCH) was the predominant metabolite. Median (and 95th percentile) concentrations (in μg/L) increased from <LOQ (0.09) in 2006, to <LOQ (1.02) in 2009 to 0.39 (2.09) in 2012. All oxidized DINCH metabolites (OH-MINCH, cx-MINCH, oxo-MINCH) correlated strongly among each other (ρ>0.75, p < 0.001). The median (95th percentile) DINCH intake in 2012 was calculated to be 0.14 (1.07) μg/kg body weight/day which is considerably below daily intakes currently deemed tolerable. DINCH is regarded to have a preferred toxicological profile over certain anti-androgenic phthalates. The continuation of DINCH measurements in the ESB Hum and other human biomonitoring studies like the German Environmental Survey (GerES) allows tracking the development of DINCH body burdens, the distribution of exposure levels and daily intakes, providing basic data for future toxicological assessment and further epidemiological studies. doi:10.1016/j.ijheh.2013.08.004

Stable water isotopes in precipitation in the Mekong Delta, Vietnam

Abstract

Bisphenol A in 24 h urine and plasma samples of the German Environmental Specimen Bank from 1995 to 2009: A retrospective exposure evaluation

Koch, Holger M.; Kolossa-Gehring, Marike; Schröter-Kermani, Christa; Angerer, Jürgen; Büring, Thomas Journal of Exposure Science and Environmental Epidemiology 22 (2012), November/December, 610-616 Human exposure to Bisphenol A (BPA) is omnipresent. Both the extent of the exposure and its toxicological relevance are controversially discussed. We aim to reliably determine and evaluate the extent of BPA body burden in the German population from 1995 to 2009 based on 600 24 h urine samples and corresponding plasma samples from the Environmental Specimen Bank. We determined total and unconjugated BPA in urine and plasma using on-line solid-phase extraction high-performance liquid chromatography coupled to isotope dilution tandem mass spectrometry with a limit of quantification (LOQ) of 0.1 μg/l. In the stored urines, total BPA was quantifiable in >96% (median: 1.49 μg/l; 95th percentile: 7.37 μg/l), whereas unconjugated BPA was quantifiable only in <15% of the samples. Total BPA concentrations decreased over time, but 24 h urine volumes increased. Therefore, daily intakes calculated from the 24 h urines remained rather constant at a median of 0.037 and a 95th percentile of 0.171 μg BPA/kg body weight/day. In 60 corresponding plasma samples, total BPA levels were generally below the LOQ of 0.1 μg/l and, if quantifiable, most BPA was unconjugated, thus hinting to external contamination. We see total BPA in urine as the most appropriate and robust marker for BPA exposure assessment (if controlled for BPA contamination). Unconjugated BPA in urine and unconjugated or total BPA in plasma where contamination or breakdown of the glucuronide cannot be ruled out are of no value for human exposure assessment. doi:10.1038/jes.2012.39

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