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).     

Natural resource management in a protected area of the Indian Himalayas: a modeling approach for anthropogenic interactions on ecosystem

The concept of ecosystem conservation as a broad theme came into existence during the 1970s under the Man and Biosphere Programme (MAB) of the United Nations Educational, Scientific and Cultural Organization (UNESCO). The Indian Government followed this approach and chose the method to segregate the landscape for conservation of the ecosystem as well as for the development of the local economy and its people. We have examined the effect of this policy and concurrently developed a theoretical modeling approach to understand how human behavior is changing under shifting political, socioeconomic and environmental conditions. A specific focus has been on how the landscape is changing in the mountains of the Indian Himalayan region where about 10% of the total geographical area is converted into protected landscape for conservation of biodiversity. For local people living in the Himalayan mountains in India, agriculture is the main land use activity and is strongly linked to the forests in providing sustainability. There are several branches in the rural ecosystems where the local people's economy was centered. These include agriculture, animal husbandry, medicinal and aromatic plants cultivation, forest resource collection, tourism and other occupations. The greatest proportion of the population was engaged in the agriculture sector, whose contribution is high in the rural economy (61%); followed by animal husbandry (19%), forest resource collection for economic gain (18%), and medicinal and aromatic plants cultivation (1.5%). However, three decades ago the animal husbandry branch of the rural ecosystem was contributing the maximum share towards rural household income (40%) followed by tourism (35.2%), and lastly agriculture (14%). The desire of farmers to secure the optimum output from agricultural land use has resulted in an increase for resource collection from the forests. The people's perception (n = 1,648) regarding overall changes occurring in the region was varied and most showed that the current trend within rural ecosystems has emerged because of the implementation of conservation policies/creation of national park and biosphere reserve (80%), followed by limitation (22%), climate (20%), population growth (7%), national economy (10%) and least by socioeconomic change (5%). The theoretical agent model developed here draws attention to agent/farmer behavior and land resource use for his livelihood in the temporal dimension. The current study would be helpful to introduce new approaches for the development of the methodological and theoretical aspects associated with the complex human and ecosystem interactions in the Himalayan mountains for sustainable landscape development.     

好氧污泥颗粒化中胞外聚合物（EPS）的动态变化

在SBR中分别运行普通活性污泥和好氧颗粒污泥工艺,考察普通絮体污泥颗粒化过程中EPS的组分变化和分布情况.结果表明,通过减少沉淀时间可以获得质量高的颗粒污泥,污泥系统中的EPS可划分为紧密结合型、松散结合型和溶解性3种;普通污泥期、颗粒污泥初期和颗粒污泥稳定期的EPS含量均以紧密结合型EPS为主,颗粒污泥中总EPS和溶解性EPS含量均高于普通污泥,且颗粒形成初期溶解性EPS增长明显;颗粒污泥中紧密结合型EPS含量相对稳定,松散结合型EPS在不同污泥中含量很低,一个典型反应周期中蛋白质和多糖的变化趋势普遍是先降低后上升,普通污泥和颗粒污泥EPS中蛋白质含量均高于多糖,颗粒形成初期EPS中蛋白质含量有明显上升;普通絮体污泥中EPS和细菌分布均匀,颗粒污泥的表层聚集大量的细菌、内部主要成分是EPS.     

Exploring the possibility of a systematic and generic approach to social sustainability

There is a growing need to understand how existing concepts and tools for sustainability relate to each other and to a robust, trans-disciplinary systems perspective for sustainability. As a response, a group of scientists, including some of the authors, have developed a framework based on backcasting from sustainability principles over the last 20 years – the Framework for Strategic Sustainable Development (FSSD), also known as The Natural Step Framework. The intent of this study is to scrutinize the existing framework as regards its social dimension. The study demonstrates dichotomies and lack of robustness and proposes a way forward to make the social dimension of the FSSD more cohesive as well as operational.     

Occupational exposure to fluorinated hydrocarbons during refrigeration repair work

This study describes refrigeration repair workers' occupational exposures to halogenated refrigerants, focusing on difluorochloromethane (HCFC 22), tetrafluoroethane (HFC 134a) and a mixture of tri-, tetra- and pentafluoroethane (R404A) in 30 work operations. Unlike earlier reported studies, the present study includes working procedures involving welding in order to measure possible occupational exposure to decomposition products. The measurements included hydrogen fluoride (HF), hydrogen chloride (HCl), phosgene (COCl2) and volatile organic compounds (VOC). The exposures were assessed during work operations on small-scale cooling installations like refrigerators and freezers. The repair workers' occupational exposures to refrigerants were moderate, and the major part of the exposures were associated with specific working procedures lasting for relatively short periods of time (<20 min). During these exposure events the concentrations were occasionally high (up to 42434 mg m(-3)). Although welding operations lasted only for short periods of time, HF was detected in 9 out of 15 samples when HCFC 22, HFC 134a or R404A had been used. Hydrogen chloride was detected in 3 out of 5 samples in air polluted with HCFC 22. Phosgene was not detected. A large number of VOCs in various concentrations were found during welding. Except for the applied refrigerants, halogenated compounds were only found in one sample.     

Cytotoxicity of TBBPA and effects on proliferation, cell cycle and MAPK pathways in mammalian cells

Poly-brominated flame retardants are ecotoxicologically relevant chemicals that can show high persistency in environmental samples and bioaccumulation in marine and fresh water animals. One of the most widely used compound is tetrabromobisphenol A (TBBPA). Until today, the toxicological data are rather fragmentary. Our studies on acute and sub-acute toxic effects with established cell lines demonstrate that TBBPA interferes with cellular signaling pathways. Cell viability is significantly reduced in a time- and concentration-dependent manner. The observed EC50 for rat kidney cells (NRK) was 52 microM (27 mg/l), 168 microM (90 mg/l) for A549 human lung cells, and 200 microM (108 mg/l) for Cal-62 human thyroid cells, respectively. The comparison of TBBPA with the non-brominated substance bisphenol A (BPA) clearly demonstrates that only the brominated compound exerts these effects on proliferation and cell viability. Cell cycle regulation was influenced considerably in Cal-62 cells, showing an explicit G2/M arrest in the cell cycle at TBBPA concentrations higher than 75 microM. Cellular signaling pathways directly connected to these affected parameters, e.g. the mitogen activated protein kinase (MAPK) cascades, are partly influenced in a cell specific and dose dependent manner. The extracellular-signal regulated kinase (ERK) is deactivated in NRK and A549 cells and activated in Cal-62 cells with increasing TBBPA concentrations.     

Lignite coke moving bed adsorber for cement plants – BAT or beyond BAT?

The IPPC Directive requires permits which must contain emission limit values and other conditions based on BAT. The BAT are characterised and the terms ‘conditional BAT’ and ‘beyond BAT’ are defined and explained. The borderline between BAT and beyond BAT is explained by means of an outstanding example which is the lignite coke moving bed adsorber for the abatement of the waste gas from a cement plant where waste for co-incineration is fed to a considerable extent is described in detail. Worldwide, this technique has been successfully applied at one cement plant for sixteen years.     

Polychlorinated biphenyls in polysulfide sealants--occurrence and emission from a landfill station

Approximately 80,000 kg polysulfide sealant containing 10,000-18,000 kg polychlorinated biphenyls (PCB) was deposited at a Swedish municipal landfill station during 1965-1973. Investigations during 1994 showed that soil layers underneath the landfill had concentration of PCB not alarmingly high. The concentration of PCB congeners in ground water samples was elevated 4-750 times compared to a reference sample. Based on samples of ground water, leachate water, and flux chambers measuring evaporation of PCB from the landfill surface, the emission of PCB was estimated to be 1 g sigmaPCB/yr. This very low rate was attributed to the high sorptive capacity of the sealant. Compared to a reference site, the evaporation flux was elevated for the most volatile congeners, but factors 20-1400 lower than from another landfill which was contaminated with PCB in paper-pulp fibres.