Universiteit Leiden Universiteit Leiden

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Onderzoeksproject

Flows of six heavy metals

Can we provide the Dutch government with an integrative framework, wherein the various policies can be placed and the need for further measures can be identified?

Looptijd 1993  -  1995
Contact Ester van der Voet
Financiering Ministry of Housing, Physical Planning and the Environment (VROM)

Heavy metals are since long a concern of environmental policy. In The Netherlands, standards have been set, measures have been taken and policies have been formulated for various aspects of the heavy metals problem. This study has been undertaken to provide the Dutch government with an integrative framework, wherein the various policies can be placed and the need for further measures can be identified. For six heavy metals - copper, zinc, lead, chromium, cadmium and mercury - the flows through the economy and the environment were quantified, thus providing an overview of the metals' chain from cradle to grave. These overviews have been translated into substance flow models with help of the computer tool SFINX, which have been used to calculate the origins of several specific environmental problems and calculate the effectiveness of certain possible abatement measures. It appeared that, although some problems occurred for one metal only, there were several problems concerning the group of metals as a whole due to their non-degradability. One problem is the metals accumulation in agricultural flows such as soils and manure, as a result of constant recycling. Another is the content in waste products such as sewage sludge, compost and fly-ash, which makes re-use of these materials impossible.