Ecotoxicity and Human Toxicity Impact Footprint in Urban System
Résumé
Up to date, carbon footprint by transportation and energy consumptions are mainly studied at urban (and national) systems level. Eventhough air pollution and other significant emissions are rather well quantified and monitored in many cities, the ecotoxicity and human toxicity impact footprint should be studied more thoroughly. In this study, we analyzed the concentrations of chemical elements and calculated the ecotoxicity and human toxicity impact footprint by indusrial activities in Ust-Kamenogorsk city, located in East Kazakhstan. It is well known that plants, especially growing in the vicinity of industrial zones, can be easily and effectively used for environmental pollution biomonitoring, particularly in urban areas. For our study, leaves of poplar (Populus nigra L.) were chosen as a monitor to provide фт information on air pollution. In the selected 101 samples, the concentrations of 28 chemical elements were determined by neutron activation analysis. As an intermediate result, the sites and areas with abnormal contents of typomorphic pollutants have been revealed. Based on the quantified concentrations of chemical elements (Ag, As, Ba, Be, Co, Cr, Sb and Zn), ecotoxicity and human toxcity impact footprint were calculated per km2 of the territory surface (CTUh/km2; CTUeco/km2), using USEtox models. Finally, we could show (by mapping techniques) toxcity impact footprints in each sector and part of the city. Maps of total toxicity impact footprint (both for ecotoxicity and for human toxicity) were also constructed, which took into account the contribution of each calculated element (without considering antagonistic and synergistic effects). And we figured that these maps matched to Zn emission map, seeing its toxicity levels are about 95% of the total ones.