Developpement d'un modele de caracterisation des impacts lies aux emissions toxiques interieures en milieu de travail dans le cadre de l'analyse de cycle de vie

In Life cycle assessment (LCA) field, impact of outdoor toxic emissions on human health can be calculated in LCA methods thanks to characterization factors. On the contrary, indoor emissions and more specifically occupational indoor emissions are not taken into account by LCA methods. However, eight hours per day are spent at work. Furthermore, it has been demonstrated that indoor intakes are usually higher than outdoor intakes because of higher concentrations. Therefore, it would be helpful to characterize the impact of occupational indoor emissions within LCA. Consequently, the research hypothesis is: "Occupational indoor emissions have a higher human health impact than outdoor emissions currently characterized within LCA and it would be helpful to take them into account within LCA methods". Objectives linked to this hypothesis are: 1) To develop a new model which would enable the taking into account of occupational indoor emissions within LCA, to calculate characterization factors for a set of substances and to compare occupational indoor and outdoor impacts, 2) To develop a methodology which would take into account indirect occupational indoor impact (impacts due to all industrial sectors from the supply chain of a product) and 3) To compare occupational indoor impact of organic substances and particulates.;LCA is an environmental tool which enables the comparison of environmental impacts of products or services. It enables for example the calculation of impacts on human health of toxic emissions. The objective related to LCA is to take into account all impacts related to a product and indoor emissions should be taken into account as they have an impact on workers health and on people in households. However, they are taken into account within LCA only with semi-quantitative or empirical models. Recently, characterization models usually used for outdoor emissions have been coupled to specific indoor fate models to calculate the impact of indoor emissions. Nevertheless, this model could only been applied for households because of the use of an indoor emission parameter which is not available for the occupational case. Indeed, industrial sectors measure indoor concentration data instead of emissions. That is why, it would be more suitable to develop a model with indoor concentration as an input parameter.;First, a model which characterizes the impact of occupational indoor emissions depending on the indoor concentration per industrial sector has been developped. This model has been developped specifically for the inhalation path et is based on an indoor one-box fate model. This model has then been applied to 22 organic substances and 18 industrial sectors and compared the related impact of outdoor emissions with the USEtox characterization model. Results show that occupation indoor impact can be 100 to 1000 times higher than outdoor impact for a same functional unit. This can be explained by dilution volumes considered by the models and population density which is higher at the workplace.;Secondly, this model has been applied in a case study of a chair. Chair impacts of outdoor, occupational and household emissions were calculated separately and compared. For the characterization of the impact of outdoor and household emissions, existing characterization models were used. Furthermore, occupational indirect impacts were considered by using Leontief method base on input-output tables. Results show that indoor impact (household or occupational) is 10 to 1000 times higher than related outdoor impact. Furthermore, occupational indirect impact is higher than related direct impact, showing that this should be considered in the study.;Finally, A comparison between organic substances and particulates impact from outdoor and occupational indoor emissions were compared in the foundry industry. This study was done because of the higher known impact of particulates compared to organic substances. Results show this trend because of the very high effect factors considered for particulated by characterization models. Nevertheless, when compared, outdoor and occupational indoor impact of particulates is similar. It can consequently been said that occupational indoor impact is higher than related outdoor impact because of the higher impact of organics substances in indoor environments.;In conclusion, the model developped in this thesis enable the characterization of impacts linked to occupational indoor emissions. Furthermore, this model can be applied for organic substances as well as particulates. A new methodology also enable the taking into account of occupational indirect impact, showing that all the supply chain should be considered in case studies. The next step could consist in integrating the developped model in existing characterization models like USEtox in order to consider occupational indoor impact in further studies. Furthermore, occupation indoor characterization factors could be spatialized because working conditions depends greatly on the country and this should be taken into account by the model.