Universiteit Leiden Universiteit Leiden

Nederlands English

Onderzoeksproject

Substances from Cradle to Grave

Materials balances have been used in the recent past for the analysis of substance oriented environmental problems and the formulation of measures for environmental policy. In this study an integrated tool, based on the materials balance principle, has been developed for the analysis of both environmental and economic flows of a substance or a group of substances.

Looptijd 1991  -  1996
Contact Ester van der Voet
Financiering Dutch Organisation for Scientific Research (NWO)

This integrated analysis, called Substance Flow Analysis (SFA), makes it possible to trace environmental problems back to their economic origins, and to determine the effectiveness of certain policy measures to reduce environmental problem flows. A methodology was developed consisting of three major steps: 

  1. definition of the system: choice of
    • substance(group)
    • geographical region
    • time period
  2. quantification of the overview of stocks and flows by
    • bookkeeping
    • static modeling
    • dynamic modeling
  3. interpretation of the results 
    • direct interpretation via problemflows
    • indicators. 
       

The developed methodology has been implemented in the computerprogram SFINX. 

Two case studies were performed: cadmium and nitrogen in the European Union. In both case studies the goal was to trace the economic origins of specific pollution problems and to calculate the effectiveness of possible abatement measures. For cadmium the main result was that measures which normally are sufficient to reduce problemflows are not effective for cadmium. This is being caused by the fact that cadmium is produced as a byproduct of the zinc production and that therefore its supply is inelastic. For nitrogen the most interesting conclusion was that the only way to solve the problem of the leaching of nitrates to the groundwater requires a totally different agricultural production in order to produce a totally different diet for the EU population.