Identifying the drivers of environmental risk through a model integrating substance flow and input-output analysis

In addition to risk assessment, effective environmental risk management requires information indicating sources and driving forces of risks. Systematic substance flow analysis can indicate critical emissions and potential strategies of risk reduction by mapping the flows of toxic substances throughout the economic system. This research developed an integrated modeling framework for examining the connections between driving forces and environmental risk. Three methodologies, including substance flow modeling, input-output model, and environmental risk assessment, were integrated into the framework. We built a model of lead flow system integrating four risk chain modules, which are corresponding to the Driver, Presser, State, and Impact component of DPSIR environmental management framework. Thus, risk can be backtraced to its exposure pathways, emission sources, and driving forces. In the results, Sankey diagrams are presented to highlight the sources and driving forces of the lead flow system. Among the driving forces, unit change in the demand on computer products is associated with the most significant change in risk of lead. Backtracing the contributions of the causes along the risk chain, the sectors of electronic product and computer product had driven the electronic supply chain which contributes the greatest to risk of lead by discharging into water body.