Modifying national industrial structure for reducing heavy metals in China: A nexus-based multi-objective optimization approach

Heavy metals (HMs) exhibit significant toxicity and can lead to a range of health issues. Certain HMs share common emission sources, necessitating an exploration of the nexus among various HMs for achieving collaborative reductions. Considering the efficacy and feasibility of industrial modification to environmental pressures, this paper proposes a novel nexus-based optimization approach based on nexus analysis, multi-region inputoutput (MRIO) table, and multi-objective optimization to mitigate atmospheric HMs. The atmospheric HM emission inventory in 2017 is first compiled. Subsequently, the Integrated Nexus Strength of HMs Risk (HMR-INS) is proposed and employed to determine the range of sectoral output variations. Finally, a multi-objective optimization approach is employed based on the MRIO table in 2017. Compared with the traditional optimization method, the proposed approach performs better regarding HM-related risks and total output, leading to a 1.9 million tons increase in reduction on HM-related risks and a 1.37 trillion yuan increment in total output. Some further analyses are also given to provide feasible solutions for industrial modification, which considers both the economic efficiency and the stability of the industrial structure.