Integral assessment of estrogenic potentials of sediment-associated samples

GOAL, SCOPE AND BACKGROUND: Exogenic endocrine-active substances are also called 'Endocrine Disrupting Chemicals' (EDC). They imitate or hinder the function of natural endogenic hormones or disturb the synthesis or the metabolism of hormones or of hormone receptors. The Enzyme-Linked Receptor Assay (ELRA) can detect estrogenic and anti-estrogenic effects at the level of receptor binding and is a useful tool for the integrative detection of contaminant effects. Although the test system has been used repeatedly in sediment assessments, the questions have remained concerning how it responds to variations in the physico-chemical matrix. For some bioassays, the salinity of the sample is a critical factor. This is especially relevant when testing wastewater samples or when sediment-associated samples in the tidal reaches of rivers are tested. Sediments in the tidal reaches of rivers change their salinity several times a day. Against this background, it would be beneficial to have a test procedure of known salinity tolerance. On account of this, the salinity tolerance of the ELRA was tested, assessed with reference substances at several salinity levels, and compared with the E-Screen method and a Yeast Estrogen Screen (YES), which are also frequently applied in environmental testing. The aim of this paper was to explore when the salinity limits within these test procedures are applicable. The trials should reveal the working range to be expected, characterize the salinity-dependent variations in sensitivity of the test, and provide options for methodological adjustments to improve the stability against increased salinity. METHODS: The ELRA was carried out with the human Estrogen Receptor alpha. (ER) using the same principle like a competitive immunoassay based on ligand-protein interaction. However, an essential difference is the use of a physiologically relevant receptor instead of an antibody as a linking protein. The ELRA measures the competition of sample estrogens and anti-estrogens against estradiol supplied as a BSA-coating conjugate for the binding site of dissolved ER. Estradiol or xeno-estrogen binding is quantified by a biotynilated anti-ER antibody and the subsequent measurement of peroxidase activity by a streptavidin-POD-biotin complex. The E-Screen was performed with the human breast cancer cell line MCF-7, which expresses the estrogen receptor constitutively. Cell proliferation depends on binding of estrogens or xeno-estrogens with the receptor. After incubation, estrogen-dependent cell growth was measured by sulforhodamin B staining. The YES was performed with a recombinant yeast strain, transfected with a receptor and a reporter plasmid bearing the estrogen receptor and a vitellogenin gene fused with the reporter gene lacZ. Estrogen or xeno-estrogen-dependent gene induction was measured indirectly by LacZ activity. The salinity levels were simulated in varying concentrations with NaCl from 0 to 40 per thousand or Artificial Sea Water (ASW) from 0 to 32 per thousand. RESULTS: The study characterized the factor 'salinity' for the prospective application fields of the ELRA. With reference substances such as 17-beta-estradiol, the ELRA showed classical sigmoidal concentration-effect relations in a range from 0.05 to 100 microg/l under physiological conditions. After a methodological adjustment to compensate decreasing receptor-binding affinity of estrogens and xeno-estrogens at higher salinity levels, the ELRA became applicable under salinity conditions up to concentrations of 20.5 per thousand. In tests, the ELRA reached under the influence of salinity a mean limit of detection of 0.062 microg/l 17-beta-estradiol. The mean relative inter-test error was around 11%. Above concentrations of 20.5 per thousand there is a risk of false negative assessment. Compared with the E-Screen method using the MCF7 cell line and the yeast estrogen test system (YES), the ELRA shows a lower sensitivity to 17-beta-estradiol. In the E-Screen, the cell proliferation was strongly reduced by sodium chloride induced cytotoxicity. In comparison with the E-Screen, the salinity tolerance of the YES and YAS methods is significantly higher. DISCUSSION: Despite adaption, total salinity tolerance could not be achieved with the ELRA. Freshwater samples were generally appraisable. Higher salinity levels above 20.5 per thousand would tend towards false negative results. The low inter-test error of 11% makes the ELRA suitable for the detection of estrogenic and anti-estrogenic potentials of single substances, substance mixtures, and of environmental samples. CONCLUSIONS: The ELRA is very fast and reproducible, it can be used for high-throughput screening in a microplate format at low cost, it is robust to microbial contamination, and is less susceptible to cytotoxic interferences than cell culture methods. RECOMMENDATIONS AND PERSPECTIVES: In their established form, the YES and the E-Screen methods are not applicable for liquid phase testing at higher salinity conditions. The salinity-adapted test version of the ELRA described here shows a broader working range for samples. Native water samples of more or less brackish origin or high-salinity effluent samples are testable. Results of tests with sediment associated samples of different salinity will be subject of a forthcoming publication.     

Evidence for life history changes in high-altitude populations of three perennial forbs

Relatively little is known about how the life histories of perennial forb species, and especially their lifetime patterns of growth, vary across environmental gradients. We used a post hoc approach (herb-chronology) to determine plant age and previous growth (width of successive annual rings in roots) in three species of perennial forb (two long-lived species [Penstemon venustus, Lupinus laxiflorus] and one short-lived [Rudbeckia occidentalis]) along a 1000-m altitudinal gradient in the Wallowa Mountains (northeast Oregon, USA). Plants from the highest altitude tended to be considerably older and produced up to five times as many flowering shoots as lowland plants. In addition, mean ring widths of high-altitude plants were about half those of lowland plants. In plants from low and intermediate altitudes, ring width either decreased linearly or varied inconsistently during the life of the plant. In contrast, ring widths of high-altitude plants increased at first and later decreased, resulting in curvilinear growth trajectories that were highly consistent among species. Together, these data for three ecologically distinct forb species provide evidence of a consistent shift toward more conservative and strongly constrained life histories at higher altitudes. More generally, the results indicate the possible importance of changes in selection pressures across strong environmental gradients on life history strategies within a single species.     

Polycyclic aromatic hydrocarbon (PAH) contamination of surface sediments and oysters from the inter-tidal areas of Dar es Salaam, Tanzania

Surface sediment and oyster samples from the inter-tidal areas of Dar es Salaam were analyzed for 23 polycyclic aromatic hydrocarbons (PAHs) including the 16 compounds prioritized by US-EPA using GC/MS. The total concentration of PAHs in the sediment ranged from 78 to 25,000 ng/g dry weight, while oyster concentrations ranged from 170 to 650 ng/g dry weight. Hazards due to sediment contamination were assessed using Equilibrium Partitioning Sediment Benchmarks and Threshold Effect Levels. Diagnostic indices and principle component analysis were used to identify possible sources. Interestingly, no correlation between sediment and oyster concentrations at the same sites was found. This is supported by completely different contamination patterns, suggesting different sources for both matrices. Hazard assessment revealed possible effects at six out of eight sites on the benthic communities and oyster populations. The contribution of PAH intake via oyster consumption to carcinogenic risks in humans seems to be low.     

Reduced analytical availability of polychlorinated biphenyls (PCB's) in colored surface water

It has been generally accepted, during the last few decades, that the dissolved natural organic matter in water [DNOM] appearing as yellow brownish color, has become more and more "polluted" by inorganic and organic micro-pollutants. Due to the complexing properties of NOM, lipophilic organic micro-pollutants, such as, PCBs will be mobilized into water together with the DNOM. A mixture of eight PCBs, with Cl-content from tri-Cl to hepta-Cl, was added to solutions of ten different DNOMs. The DNOMs were aqua's solutions of RO-(reverse osmosis)-isolated material, having approximately the same concentration of carbon. After a contact time of three days, standard analytical PCB-method was used to determine the recovery of the added PCBs. The results show that the analytical availability of the added PCB was significantly reduced in the presence DNOM, compared to distilled water. The percentage loss in recovery of PCB increased with the content of Cl, in mean, from 3%/mg C for tri-Cl to 9%/mg C for hepta-Cl. The results also suggest that the analytical recovery of PCB was affected by the quality and the nature of the organic matter. For example the longer the DNOMs had been in the aquatic phase, the less efficient they are attached to the PCBs.     

Origin of middle rare earth element enrichment in acid mine drainage-impacted areas

The commonly observed enrichment of middle rare earth elements (MREE) in water sampled in acid mine drainage (AMD)-impacted areas was found to be the result of preferential release from the widespread mineral pyrite (FeS₂). Three different mining-impacted sites in Europe were sampled for water, and various pyrite samples were used in batch experiments with diluted sulphuric acid simulating AMD-impacted water with high sulphate concentration and high acidity. All water samples independent on their origin from groundwater, creek water or lake water as well as on the surrounding rock types showed MREE enrichment. Also the pyrite samples showed MREE enrichment in the respective acidic leachate but not always in their total contents indicating a process-controlled release. It is discussed that most probably complexation to sulphite (SO₃ ^2?) or another intermediate S-species during pyrite oxidation is the reason for the MREE enrichment in the normalized REE patterns.     

Is there a Relation Between Ecological Practices and Spirituality? The Case of Benedictine Monasteries

For decades there has been a controversial debate over how far religious faith communities are specifically engaged in ecological practices (EP). Therefore we studied four Austrian and two German Benedictine monasteries religious ethics and spirituality as a means of a driving force for initiating EP. We draw upon theories of organizational learning processes and capacity-building of sustainability to interpret our empirical findings. The majority of monasteries are highly engaged in EP, initiated either as an outcome of individual activities or through a specific mostly informally acting group, but rarely an organizationally or systematically integrated goal of the monasteries, or a focus of capacity building. Monasteries follow a technical and economic decision-making process in implementing EP. Spirituality plays a limited role in the initiation of EP. The environment of monasteries–acceptance or critique against ecological practices–influences the monasteries decisions. Institutionalization of ecological practices into the monasteries organizational structure is rare.     

A performance-based tabular approach for joint systematic improvement of risk control and resilience applied to telecommunication grid,gas network,and ultrasound localization system

Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales....     

Project house water: a novel interdisciplinary framework to assess the environmental and socioeconomic consequences of flood-related impacts

Protecting our water resources in terms of quality and quantity is considered one of the big challenges of the twenty-first century, which requires global and multidisciplinary solutions. A specific threat to water resources, in particular, is the increased occurrence and frequency of flood events due to climate change which has significant environmental and socioeconomic impacts. In addition to climate change, flooding (or subsequent erosion and run-off) may be exacerbated by, or result from, land use activities, obstruction of waterways, or urbanization of floodplains, as well as mining and other anthropogenic activities that alter natural flow regimes. Climate change and other anthropogenic induced flood events threaten the quantity of water as well as the quality of ecosystems and associated aquatic life. The quality of water can be significantly reduced through the unintentional distribution of pollutants, damage of infrastructure, and distribution of sediments and suspended materials during flood events. To understand and predict how flood events and associated distribution of pollutants may impact ecosystem and human health, as well as infrastructure, large-scale interdisciplinary collaborative efforts are required, which involve ecotoxicologists, hydrologists, chemists, geoscientists, water engineers, and socioeconomists. The research network “project house water” consists of a number of experts from a wide range of disciplines and was established to improve our current understanding of flood events and associated societal and environmental impacts. The concept of project house and similar seed fund and boost fund projects was established by the RWTH Aachen University within the framework of the German excellence initiative with support of the German research foundation (DFG) to promote and fund interdisciplinary research projects and provide a platform for scientists to collaborate on innovative, challenging research. Project house water consists of six proof-of-concept studies in very diverse and interdisciplinary areas of research (ecotoxicology, water, and chemical process engineering, geography, sociology, economy). The goal is to promote and foster high-quality research in the areas of water research and flood-risk assessments that combine and build off-laboratory experiments with modeling, monitoring, and surveys, as well as the use of applied methods and techniques across a variety of disciplines.     

Multi-component analysis of polar water pollutants using sequential solid-phase extraction followed by LC-ESI-MS

A multi-component screening analysis method for polar to medium-polar water pollutants was developed. Sample clean-up and group separation are performed by sequential solid-phase extraction (SSPE) using automated SPE with C18 and polymeric sorbent materials. Analyses are performed by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) using a single-quadrupole instrument. More than 90 priority compounds of environmental interest--comprising the most important chemical and substance classes: phenols, carboxylic acids, aromatic sulfonates, aromatic amines, pharmaceuticals, surfactants, dyes, and pesticides--have been chosen for the experiments. The compounds are divided by the SSPE procedure into 3 different polarity classes. The extraction recoveries were determined in the 3 fractions for every single substance, and were for most of the analytes in the range of 50-100%. A mixture of hexane-dichloromethane was used for the elution of nonpolar compounds like alkylphenols from C18. Methanol and acetone are well suited for the elution of more polar substances. The limits of detection (LODs) were determined for all compounds. Effluents from municipal and industrial wastewater treatment plants (WWTPs) treating waste water from textile industries; and the corresponding receiving waters (rivers and lakes) have been analysed with the developed method. Urban and industrial pollution was observed in rivers and streams in the area north of Milan, Italy. In the water samples different phenols (nitrophenols, bisphenol A, nonylphenol), alkylphenol ethoxylate surfactants, their metabolites with endocrine disrupting potential, aromatic sulfonates, linear alkylbenzenesulfonate surfactants, dyes, pesticides, pharmaceuticals, and a dichlorobenzidine compound were identified.