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International audience ; Long-living wood products can contribute to the mitigation of climate change in many ways. On the one hand, they act as a carbon pool during their service life, as they withdraw CO2 from its natural cycle. After their service life, they can substitute for fossil fuels if they are incinerated in adequate furnaces. On the other hand, wood products can substitute for more energy intense products made of 'conventional' materials. This paper quantifies the substitution and carbon pool effects of an increased use of wood in the building sector in Switzerland for the years 2000-2130. For this purpose, life cycle data on greenhouse gas (GHG) emissions of 12 wood products and their substitutes is used as proxies for the most important groups of building products used in construction and in interior works; this data is linked to the forecasted wood flows for each group of building products in a cohort-model. For the political assessment, GHG effects occurring abroad are distinguished from GHG effects occurring in Switzerland. The results show that the C-pool effect of an increased use of wood products with long service life is of minor importance; the substitution effects associated with the thermal use of industrial and post-consumer waste wood as well as with the substitution of 'conventional' materials are much more relevant, especially on a long-term. For construction materials, the Swiss share of the GHG effect related to the material substitution is relatively high, as mainly nationally produced concrete, mineral wool, and bricks are substituted for. For products used in interior works, the Swiss share of the GHG effect related to the material substitution is rather small (or even negative for single products) because mainly imports are substituted, such as ceramic tiles or steel produced in the EU. The results are rough estimates. Nonetheless, these calculations show that an increased use of wood in the building sector is a valid and valuable option for the mitigation of greenhouse gas ...

Most studies of potentially hazardous substances focus on aspects of their occurrence and fate in the environment (monitoring and modelling studies) to estimate the environmental impact and the potential exposure of humans. In order to evaluate emission sources, to recognise environmental impacts at an early stage, and to take efficient legislative or technical measures, it is essential to know their behaviour in the anthroposphere as a function of time. So far, only very few investigations of this type exist for chemicals. In regular risk assessments, only rather limited knowledge is available concerning the behaviour of chemicals in the anthroposphere (production data, substance quantities in products, recycling rates, emissions occurring during use, etc.) or their lifecycle, and no information at all about their behaviour as a function of time. For this reason, it is these aspects that were investigated in a case study within the framework of the national research programme NRP50 for selected brominated flame retardants with endocrine-disrupting potential (pentabromodiphenyl ether, hexabromocyclododecane) or the potential to degrade to such substances (decabromodiphenyl ether). A dynamic substance flow analysis (SFA) model was performed for Switzerland for the time period 1980–2020. In this review paper (a) we present a summary of typical results (system overview, consumption trends/application patterns, anthropogenic stocks and their changes, emission trends including major sources and environmental fate), (b) we summarize the effectiveness of recent risk-reduction measures in Switzerland and (c) we indicate serious remaining data gaps and recommend further important measures for risk reduction. For the future, we suggest improving the knowledge of the lifecycle of chemicals such as brominated flame retardants by applying SFA as a suitable tool to weight the effect of substance flows with respect to environmental emissions, and to serve as the basis for planning actions and measures to reduce such emissions. This is in line with one major conclusion of the NRP50 consensus platform 'Brominated Flame Retardants'.