BETR global--a geographically-explicit global-scale multimedia contaminant fate model

We present two new software implementations of the BETR Global multimedia contaminant fate model. The model uses steady-state or non-steady-state mass-balance calculations to describe the fate and transport of persistent organic pollutants using a desktop computer. The global environment is described using a database of long-term average monthly conditions on a 15° × 15° grid. We demonstrate BETR Global by modeling the global sources, transport, and removal of decamethylcyclopentasiloxane (D5).     

Monitoring of heavy metal concentrations in home outdoor air using moss bags

One monitoring station is insufficient to characterize the high spatial variation of traffic-related heavy metals within cities. We tested moss bags (Hylocomium splendens), deployed in a dense network, for the monitoring of metals in outdoor air and characterized metals’ long-term spatial distribution and its determinants in Girona, Spain. Mosses were exposed outside 23 homes for two months; NO₂ was monitored for comparison. Metals were not highly correlated with NO₂ and showed higher spatial variation than NO₂. Regression models explained 61-85% of Cu, Cr, Mo, Pb, Sb, Sn, and Zn and 72% of NO₂ variability. Metals were strongly associated with the number of bus lines in the nearest street. Heavy metals are an alternative traffic-marker to NO₂ given their toxicological relevance, stronger association with local traffic and higher spatial variability. Monitoring heavy metals with mosses is appealing, particularly for long-term exposure assessment, as mosses can remain on site many months without maintenance.     

X-ray absorption and photoelectron spectroscopy investigation of selenite reduction by FeII-bearing minerals

The long-lived radionuclide 79Se is one of the elements of concern for the safe storage of high-level nuclear waste, since clay minerals in engineered barriers and natural aquifer sediments strongly adsorb cationic species, but to lesser extent anions like selenate (SeVIO4(2-)) and selenite (SeIVO3(2-)). Previous investigations have demonstrated, however, that SeIV and SeVI are reduced by surface-associated FeII, thereby forming insoluble Se0 and Fe selenides. Here we show that the mixed FeII/III (hydr)oxides green rust and magnetite, and the FeII sulfide mackinawite reduce selenite rapidly (< 1 day) to FeSe, while the slightly slower reduction by the FeII carbonate siderite produces elemental Se. In the case of mackinawite, both S(-II) and FeII surface atoms are oxidized at a ratio of one to four by producing a defective mackinawite surface. Comparison of these spectroscopic results with thermodynamic equilibrium modeling provides evidence that the nature of reduction end product in these FeII systems is controlled by the concentration of HSe(-); Se0 forms only at lower HSe(-) concentrations related to slower HSeO3(-) reduction kinetics. Even under thermodynamically unstable conditions, the initially formed Se solid phases may remain stable for longer periods since their low solubility prevents the dissolution required for a phase transformation into more stable solids. The reduction by Fe2+-montmorillonite is generally much slower and restricted to a pH range, where selenite is adsorbed (pH < 7), stressing the importance of a heterogeneous, surface-enhanced electron transfer reaction. Although the solids precipitated by the redox reaction are nanocrystalline, their solubility remains below 6.3 x 10(-8) M. No evidence for aqueous metal selenide colloids nor for Se sorption to colloidal phases was found. Since FeII phases like the ones investigated here should be ubiquitous in the near field of nuclear waste disposals as well as in the surrounding aquifers, mobility of the fission product 79Se may be much lower than previously assumed.     

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.     

Micropollutants in three tributaries of Lake Constance, Argen, Schussen and Seefelder Aach: a literature review

A literature review made evident that in three tributaries of Lake Constance, Argen, Schussen and Seefelder Aach 82 micropollutants (including 3 metabolites of pesticides) were detected in at least one of the streams. Quality standards according to the EU Water Frame Directive (which however comprises only 16 of the detected chemicals) are not exceeded in any of the streams. The comparison of maximal values with existing threshold values and effect concentrations obtained in ecotoxicological analyses and biomarker studies revealed 35 substances to be of relevance in at least one of the three waters. These were 5 chemicals in the Argen, 31 chemicals in the Schussen, and 17 chemicals in the Seefelder Aach, for which effects on mortality, development, health or reproduction in aquatic organisms cannot be excluded.     

Polychlorinated biphenyls (PCBs) in indoor air originating from sealants in contaminated and uncontaminated apartments within the same housing estate

Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate. The PCB_tot levels in the air of the contaminated section were 168-3843 ng m⁻³ (mean: 1030 ng m⁻³), while the mean levels in the reference apartments were 6.03 ng m⁻³. The sum of the 24 measured PCB congeners in sealants from the contaminated section was 187-221 680 mg kg⁻¹. Principal component analysis revealed four groups among the sealant samples with different congener compositions, only two of which were clearly similar to known PCB mixtures, while two were not. Significant correlations and intercorrelations were observed between the lower chlorinated congeners in air and sealant, e.g. for PCB 28_air and 28_seal (p = 0.04) and for PCB 28_air and 52_air, 52_seal. However, no correlation was observed between the lower chlorinated congeners and the sums of PCB (∑PCB₆ or ∑PCB₂₄) or the higher chlorinated congeners. Analysis of air concentrations in relation to questionnaire data indicated that the indoor air levels could be reduced by increased cleaning and airing frequencies.     

Variations in occupant response with seat belt slack and anchor location during moderate frontal impacts

Both seat belt slack and anchor location are known to affect occupant excursion during high-speed frontal collisions, but their effects have not been studied at moderate collision severities. The goal of this study was to quantify how seat belt slack and anchor location affect occupant kinematics and kinetics in moderate severity frontal collisions. A Hybrid III 50th percentile male dummy was seated on a programmable sled and exposed to frontal collisions with a speed change of 17.5 km/h. The seat belt was adjusted either snugly or with 10 cm slack (distributed 60/40 between the shoulder and lap portions) and the anchor location was varied by adjusting the seat position either fully forward or rearward (seat travel = 13 cm). Accelerations and displacements of the head, T1 and pelvis were measured in the sagittal plane. Upper neck loads and knee displacements were also measured. Five trials were performed for each of the four combinations of belt adjustment (snug, slack) and anchor location (seat forward, seat rearward). For each trial, kinematic and kinetic response peaks were determined and then compared across conditions using ANOVAs. Peak displacements, accelerations and loads varied significantly with both seat belt slack and anchor location. Seat belt slack affected more parameters and had a larger effect than anchor location on most peak response parameters. Head displacements increased a similar amount between the snug/slack belt conditions and the rearward/forward anchor locations. Overall, horizontal head displacements increased from 23.8 cm in the snug-belt, rearward-anchor configuration to 33.9 cm in the slack-belt, forward-anchor configuration. These results demonstrated that analyses of occupant displacements, accelerations and loads during moderate frontal impacts should consider potential sources of seat belt slack and account for differences in seat belt anchor locations.     

RecoPhos: Full-scale fertilizer production from sewage sludge ash

The substitution potential of sewage sludge for German primary phosphate imports has been estimated as 40%. Yet, a marketable option for the full scale recovery has been lacking. This study focuses on a full-scale process for the manufacture of a P-fertilizer from sewage sludge ash (SSA) adapted from the production of Triple Superphosphate. Given (i) conformity of the input with phosphate ores mined from sedimentary deposits, (ii) comparability of the product with a commercially available P-fertilizer regarding contaminant levels, P-fractionation and yield effects, and (iii) compliance of the output with the German Fertilizer Ordinance the RecoPhos P 38 fertilizer was discharged from the waste legislation regime. The fertilizer is currently being produced at a rate of 1000 tonnes per month and sold at a competitive price.