SENS'2006 Second Scientific Conference with International Participation SPACE, ECOLOGY, NANOTECHNOLOGY, SAFETY 14 – 16 June 2006, Varna, Bulgaria AIR QUALITY ASSESSMENT BY MULTIVARIATE STATISTICS Vasil Simeonov 1 , Stefan Tsakovski 1 , Pavlina Simeonova 2 1 Faculty of Chemistry, University of Sofia “St. Kl. Okhridski”, 1164 Sofia, 1, J. Bourchier Blvd.,Bulgaria, vsimeonov@chem.uni-sofia.bg 2 Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, 72, Tzarigradsko Chaussee Blvd, Bulgaria, poly-sim@issp.bas.bg Key words: aerosols, environmetrics, apportioning, pollution sources Abstract. The present communication deals with the application of several chemometrical methods (cluster and principal components analysis, source apportioning on absolute principal components scores) to an aerosol data collection from Arnoldstein, Austria. It is convincingly shown that six latent factors explaining almost 80 % of the total variance are responsible for the data structure and are conditionally identified as “fertilizer”, secondary emission”, “lead smelter”, “traffic”, “salt” and “soil dust”. Further more, the contribution of each identified source to the formation of the particle total mass and chemical compounds total concentration is calculated. Thus, a reliable assessment of the air quality in the region of observation is achieved. The apportioning models obtained are checked for adequateness and validated. It is explained why for sodium and magnesium non-adequate models are obtained. The latent factor contribution models can be further used for risk assessment and respective decision making. Additionally, it is commented why chemometrics could be successfully applied as sustainability metrics in various aspects of interpretation of the state of “sustainable development” Introduction In the recent years the concept of sustainable development has been successfully introduced and exploited not only as legislative and political formula but also as a background of various research projects. The question asked is not if a certain activity is sustainable but what recommendation is needed in order an activity to be considered as sustainable. In sense of the environmental problems this seems quite formal and undefined [1]. For instance, the traditional acceptance of the sustainability idea is to find a sound compromise between the constantly increasing needs of the mankind for energy and raw materials on one hand, and, on the other, the social requirement for clean environment and better chances for the coming generations. It is obvious that the rapid technological and social development requires some kind of sustainability metrics in order to control and implant the system of sustainable development. The challenge to be environmentally relevant has led to the development of two important concepts for sustainability indicators: • The P – S – R indicator concept (the pressure of the socio-economic activities into natural systems leads to observable changes in the state of the environmental systems, which causes respective response or socio-economic measures to reduce the hazardous effects);