Evaluation of risks of metal flows and accumulation in economy and environment

The contrast between, on the one hand, decreasing emissions of the metals c admium, copper, lead and zinc and, on the other, their continuously increas ing input into the economy is analysed for three case studies: The Netherla nds as a whole, the Dutch housing sector and the Dutch agricultural sector. Flows of these metals through and their accumulation within the economy an d the environment have been quantified for 1990 and for a constructed stead y-state situation. To this end, the substance flow analysis method has been applied. The case studies show that there is a strong increase to be expec ted in the emissions from the 1990 to the steady-state situation. This incr ease is mainly due to the shift from landfill accumulation to emission to n on-agricultural soil. At the same time, however, there is also an increase in the emissions to other media: air, water and agricultural soil. Emission s along these critical routes with respect to human and ecotoxicity show an approximately 30% increase for cadmium, lead and zinc and more than a doub ling for copper. It is shown that this increase may lead to the surpassing of critical levels for human toxicity and terrestrial and aquatic ecotoxici ty. Some possible measures are suggested to prevent critical levels being e xceeded. (C) 1999 Elsevier Science B.V. All rights reserved.