Towards compliance with the 2021 WHO air quality guidelines: A comparative analysis of PM2.5 trends in Australia and China

作者：Xuying Ma, Lídia Morawska, Bin Zou, Jay Gao, Jun Deng, Xiaoqi Wang, Haojie Wu, Xin Xu, Yifan Wang, Zelei Tan, Ningbo Jiang, Yunzhong Shen, Danyang Li, Gao Jun, Yuanyuan Fan, Jennifer Salmond · 发表于：Environment International · 年份：2025 · DOI：10.1016/j.envint.2025.109378 · 被引用次数：17 · 研究领域：Air Quality and Health Impacts、Air Quality Monitoring and Forecasting、Climate Change and Health Impacts

In 2021, the World Health Organization (WHO) released new Air Quality Guidelines (AQG) which significantly reduced the recommended annual mean concentration of fine particulate matter (PM 2.5 ) in ambient air from 10 μg/m 3 (AQG 2005) to 5 μg/m 3 (AQG 2021). Recent studies have shown that this challenging new target may be close to or even below the background levels of PM 2.5 resulting from non-anthropogenic activities in many regions globally, such as areas affected by desert dust. This raises an important question: can countries achieve compliance with the new guideline for PM 2.5 ? Here we investigated this question from the perspective of two countries that fall on opposite ends of the spectrum of ambient air pollution. We examined historical PM 2.5 trends based on observations of annual mean PM 2.5 concentrations from 2013 to 2024 in eight capital cities of each state in Australia and 31 capital cities of each province in mainland China. A statistical model was used to differentiate the contributions of meteorological variations and anthropogenic drivers to determining the annual trends of PM 2.5 concentrations. Subsequently, we analyzed and discussed the feasibility of meeting the guidelines for each city based on these results. Our findings demonstrate that compliance with the new guideline is largely achievable, or has the potential to be achieved, in more than half of the cities in Australia. Notably, there is a high probability that a city, after meeting the guidel...