Decarbonization benefits of municipal solid waste recovery: A cross-country analysis of 32 countries

Municipal solid waste (MSW) recovery is critical to global decarbonization agendas. Existing studies have provided important insights into the environmental performance of alternative waste-treatment pathways through life-cycle and scenario-based assessments. However, less is known about whether recovery expansion translates into measurable reductions in observed carbon emissions. This study employs an instrumental-variable framework to estimate the economy-wide carbon-emission effects of MSW recovery using a 32-country panel from 1998 to 2023, addressing reverse-causality concerns in the recovery-emission relationship. The results show that, across the 32-country sample, a 10% increase in aggregate MSW recovery is associated with an average 0.95–1.15% reduction in per capita carbon emissions. This estimate reflects the net system-level effect of recovery expansion under the observed mix of recovery pathways and national conditions, rather than a common effect of individual recovery technologies. The effect varies substantially across recovery systems: energy-recovery-dominated systems show stronger mitigation effects than recycling-dominated systems, with further differences across recovery scale, energy structure, and socioeconomic conditions. Finally, selected non-sample countries are compared with the 32-country sample across key structural moderators to identify where recovery expansion is most likely to deliver large mitigation gains. Overall, the study provides cross-country causal evidence on how MSW recovery translates into economy-wide emission outcomes under different national conditions, offering a system-level basis for aligning recovery strategies with broader decarbonization goals.