Increased metal concentrations in exhaled breath condensate of industrial welders

It was the aim of this study to evaluate the effect of different devices on the metal concentration in exhaled breath condensate (EBC) and to prove whether working conditions in different welding companies result in diverse composition of metallic elements. The influence of two collection devices (ECoScreen, ECoScreen2) on detection of metallic elements in EBC was evaluated in 24 control subjects. Properties of ECoScreen and a frequent use can alter EBC metal content due to contamination from metallic components. ECoScreen2 turned out to be favourable for metal assessment. Concentrations of iron, nickel and chromium in EBC sampled with ECoScreen2 were compared between non-exposed controls and industrial welders. Metal concentrations in EBC were higher in 36 welders recruited from three companies. Exposure to welding fumes could be demonstrated predominantly for increased iron concentrations. Concentrations of iron and nickel differed by working conditions, but chromium could not be detected in EBC.     

"The upper limits of vegetation on Mauna Loa, Hawaii": a 50th-anniversary reassessment

In January 1958, a survey of alpine flora was conducted along a recently constructed access road across the upper volcanic slopes of Mauna Loa, Hawaii (2525-3397 m). Only five native Hawaiian species were encountered on sparsely vegetated historic and prehistoric lava flows adjacent to the roadway. A resurvey of roadside flora in 2008 yielded a more than fourfold increase to 22 species, including nine native species not previously recorded. Eight new alien species have now invaded this alpine environment, although exclusively limited to a few individuals in ruderal habitat along the roadway. Alternative explanations for species invasion and altitudinal change over the past 50 years are evaluated: (1) changes related to continuing primary succession on ameliorating (weathering) young lava substrates; (2) local climate change; and (3) road improvements and increased vehicular access which promote enhanced car-borne dispersal of alien species derived from the expanding pool of potential colonizers naturalized on the island in recent decades. Unlike alpine environments in temperate latitudes, the energy component (warming) in climate change on Mauna Loa does not appear to be the unequivocal driver of plant invasion and range extension. Warming may be offset by other climate change factors including rainfall and evapotranspiration.     

Dioxinbilanz für Hamburg

The sources and reservoirs of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) in the city of Hamburg, Germany, in the year 1992 were identified and quantified combining analytical data of PCDD/PCDF with statistical data on annual fluxes of materials and products. Fluxes and amounts of PCDD/PCDF were estimated for the environmental compartments water, air, and soil. Dioxin emissions originating from industrial, commercial or private activities were also calculated. Together with the analysis of the specific regional nutrition data, the human exposurevia the various pathways could be determined. It could be shown that the total PCDD/PCDF intake of individuals in Hamburg was about the same as the national average. High annual fluxes of PCDD/PCDF connected with the trade of industrial products and the waste management and disposal: system in Hamburg obviously had no influence on the human intake of PCDD/PCDF.     

Effect of orchard age on soil nitrogen transformation in subtropical China and implications

A better understanding of nitrogen transformation in soils could reveal the capacity for biological inorganic N supply and improve the efficiency of N fertilizers. In this study, a ¹⁵N tracing study was carried out to investigate the effects of converting woodland to orchard, and orchard age on the gross rates of N transformation occurring simultaneously in subtropical soils in Eastern China. The results showed that inorganic N supply rate was remained constant with soil organic C and N contents increased after converting woodland into citrus orchard and with increasing orchard age. This phenomenon was most probably due to the increase in the turnover time of recalcitrant organic-N, which increased with decreasing soil pH along with increasing orchard age significantly. The amoA gene copy numbers of both archaeal and bacterial were stimulated by orchard planting and increased with increasing orchard age. The nitrification capacity (defined as the ratio of gross rate of nitrification to total gross rate of mineralization) increased following the Michaelis–Menten equation, sharply in the first 10 years after woodland conversion to orchard, and increased continuously but much more slowly till 30 years. Due to the increase in nitrification capacity and unchanged NO₃⁻ consumption, the dominance of ammonium in inorganic N in woodland soil was shifted to nitrate dominance in orchard soils. These results indicated that the risk of NO₃⁻ loss was expected to increase and the amount of N needed from fertilizers for fruit growth did not change although soil organic N accumulated with orchard age.     

Modelling of geochemical and isotopic changes in a column experiment for degradation of TCE by zero-valent iron

Zero-valent iron (ZVI) permeable-reactive barriers have become an increasingly used remediation option for the in situ removal of various organic and inorganic chemicals from contaminated groundwater. In the present study a process-based numerical model for the transport and reactions of chlorinated hydrocarbon in the presence of ZVI has been developed and applied to analyse a comprehensive data set from laboratory-scale flow-through experiments. The model formulation includes a reaction network for the individual sequential and/or parallel transformation of chlorinated hydrocarbons by ZVI, for the resulting geochemical changes such as mineral precipitation, and for the carbon isotope fractionation that occurs during each of the transformation reactions of the organic compounds. The isotopic fractionation was modelled by formulating separate reaction networks for lighter ((12)C) and heavier ((13)C) isotopes. The simulation of a column experiment involving the parallel degradation of TCE by hydrogenolysis and beta-elimination can conclusively reproduce the observed concentration profiles of all collected organic and inorganic data as well as the observed carbon isotope ratios of TCE and its daughter products.     

An LCA model for waste incineration enhanced with new technologies for metal recovery and application to the case of Switzerland

A process model of municipal solid waste incinerators (MSWIs) and new technologies for metal recovery from combustion residues was developed. The environmental impact is modeled as a function of waste composition as well as waste treatment and material recovery technologies. The model includes combustion with a grate incinerator, several flue gas treatment technologies, electricity and steam production from waste heat recovery, metal recovery from slag and fly ash, and landfilling of residues and can be tailored to specific plants and sites (software tools can be downloaded free of charge). Application of the model to Switzerland shows that the treatment of one tonne of municipal solid waste results on average in 425 kg CO₂-eq. generated in the incineration process, and 54 kg CO₂-eq. accrue in upstream processes such as waste transport and the production of operating materials. Downstream processes, i.e. residue disposal, generates 5 kg CO₂-eq. Savings from energy recovery are in the range of 67 to 752 kg CO₂-eq. depending on the assumptions regarding the substituted energy production, while the recovery of metals from slag and fly ash currently results in a net saving of approximately 35 kg CO₂-eq. A similar impact pattern is observed when assessing the MSWI model for aggregated environmental impacts (ReCiPe) and for non-renewable resource consumption (cumulative exergy demand), except that direct emissions have less and no relevance, respectively, on the total score. The study illustrates that MSWI plants can be an important element of industrial ecology as they provide waste disposal services and can help to close material and energetic cycles.     

Gesellschaftlicher Wandel und nachhaltige Entwicklung

Zusammenfassung   Hintergrund, Ziel und Themenbereich Um die Auswirkungen des gesellschaftlichen Wandels unter dem Kriterium der Nachhaltigkeit beurteilen zu k?nnen werden demographische, soziale und kulturelle Entwicklungen in den Blick genommen. Am Beispiel der Handlungsfelder ‚Bauen und Wohnen‘, ‚Infrastruktursysteme‘, ‚Verkehr und Mobilit?t‘ werden absehbare Entwicklungen aufgezeigt, und Handlungsspielr?ume und Instrumente für eine nachhaltige Gestaltung des gesellschaftlichen Wandels beschrieben. Schwerpunkte Demographischer Wandel, Sozio-kultureller Wandel, Auspr?gung des gesellschaftlichen Wandels in Schleswig-Holstein, Handlungsfelder ‚Bauen und Wohnen‘, ‚Infrastruktursysteme‘, ‚Mobilit?t und Verkehr‘, Umweltauswirkungen des gesellschaftlichen Wandels. Ergebnisse Weniger die absolute Zahl als vielmehr das von vielerlei Einflüssen gepr?gte Konsumverhalten der Menschen stellt unter Nachhaltigkeitsaspekten ein wichtiges Kriterium das. Ein wesentliches Kennzeichen des Wandels von der industriellen zur postindustriellen Gesellschaft ist eine Pluralisierung der Lebensstile und der damit verbundenen Konsummuster in nachhaltigkeitsrelevanten Handlungsfeldern. Diskussion Eine Vielzahl von Techniken steht zur Reduzierung des Umweltverbrauchs zur Verfügung. Dazu z?hlen z. B. w?rmeged?mmte H?user sowie strom- und wassersparende Haushaltsger?te, und verbrauchsarme Fahrzeuge mit geregeltem Katalysator. Ob diese Techniken eingesetzt werden, h?ngt dabei weniger von technischen als von kulturellen, politischen und ?konomischen Weichenstellungen ab. Schlussfolgerungen Der gesellschaftliche Wandel wird, wenn nicht gegengesteuert wird, massive Auswirkungen auf die Umwelt haben. Anders als man auf den ersten Blick vermuten k?nnte, wird es keine ‚Demographie-Rendite‘ geben. Auch die Nachhaltigkeitsbilanz der Postmaterialisten kann kaum positiver bewertet werden, als die der eher materiell eingestellten Menschen. Empfehlungen und Perspektiven Die Politik sollte die mit dem gesellschaftlichen Wandel verbundenen Probleme thematisieren, ihre Auswirkungen analysieren und zusammen mit den Akteuren einen umfassenden gesellschaftlichen Dialog- und Verst?ndigungsprozess initiieren. Dabei ist mit schnellen L?sungen nicht zu rechnen, denn die Komplexit?t der Thematik, die unterschiedlichen Interessenlagen und die Vielzahl der zu regelnden Sachverhalte erfordern einen langen Atem und Zeitr?ume, die über eine Legislaturperiode hinausgehen.