Industrial metabolism : The emerging landscape of heavy metal immission in Sweden

Abstract: Since the turn of this century, technological development has drastically increased the industrial consumption of toxic metals. Once dispersed in the environment, the metals cannot be degraded but will be accumulated in soil or sediment sinks. Thus, environmental effects of heavy metal pollution tend to be permanent.In this study, methods to reconstruct the flows of heavy metals and estimate the emissions over time are presented. This is done through studies of the development of production, technology, trade and the longevity of metals in the technosphere. This last part in the chain will form the "consumption emissions". Using the concept of industrial metabolism, the total load in soil and sediment has been calculated, i.e. the development of a new "irmnission landscape" could be described/assessed. Here industrial metabolism will be illustrated by the total flow in Sweden of chromium (1920-1980), lead (1880-1980) and cadmium (1940-1990).Even though the production emissions have decreased during the last decades, the accumulation of cadmium, chromium and lead in soils and sediments will continue due to dissipative consumption losses of various products. Obviously, the anthropogenic contribution is significant, i.e. the "societal weathering rate" exceeds the natural rate. For lead the emissions from various products have been dominant and contributed with much higher release to the environment than weathering processes.For cadmium and chromium the consumption emissions have become dominant in the latest decades. Total amounts used are only 5000 tonnes for cadmium, but two millions of tonnes for both chromium and lead. However, consumption emissions from various uses of chromium and lead are less than 10% of the total amount used (15% for cadmium). The rest of these metals remain in the anthroposphere and constitute a future potential problem.Urban areas can be regarded as ecological "hot spots" for toxic metals and in some regions e.g. Stockhohn the calculated amount of chromium in soils may be as high as they are in the most polluted industrial regions today, within only a few decades. Thus, the pollution load in soils and sediments has altered from being a "defined pollution problem" within certain industrial regions to a situation where the end-use of products together with the mobility pattern of goods define the pollution problem.