The waste-environmental-economic nexus facilitates city-specific cost-effective transition for China's municipal solid waste treatment

Public summary

* A waste-environmental-economic nexus framework is developed to identify optimal strategies.

* Adopting waste-to-material strategies could reduce total environmental costs by 36.9%–78.3%.

* Significant trade-offs exist between economic and environmental outcomes across regions.

* Integrated WtE and WtM strategies are expected to yield superior outcomes for >84% of cities.

Abstract

The growing challenge of municipal solid waste (MSW) generation requires systematic solutions based on the waste-environment-economy (WEE) nexus. Here, we develop an integrated assessment framework that combines bottom-up economic costing, life cycle monetization, and scenario analysis to evaluate nine MSW treatment strategies in 352 Chinese cities. Our approach integrates 18 environmental impact categories with key economic performance indicators. The results demonstrate that waste-to-material strategies could reduce China’s total environmental costs of MSW treatment by 36.9%–78.3%, primarily driven by substantial reductions in greenhouse gas emissions and freshwater ecotoxicity. However, the WEE nexus highlights notable regional trade-offs between economic and environmental outcomes, largely due to variations in waste composition and local infrastructure. By using a composite benefit index to identify optimal MSW management pathways, we find that integrated strategies, combining incineration with material recycling (either alone or combined with bioconversion), prove cost-effective in over 84% of the studied cities. In contrast, a bioconversion-dominated strategy is most effective for the remaining cities. These findings provide spatially targeted guidance for facilitating city-specific transitions toward feasible MSW management in China.