UNDP：2026年低收入和中等收入国家环境空气质量公共投资的障碍报告（英文版）

The study identified nine key barriers that limit public investment in ambient AQ despite strong economic and health returns on investment. These barriers are interconnected and mutually reinforcing, though they vary according to the national, economic and political context of each country. The most binding constraints also differ across contexts, with some countries facing more acute challenges related to technical capacity and monitoring systems, while others are more constrained by fiscal