The role of bulk material production in atmospheric aerosol loading: pathways to sustainable practices

Abstract This study investigates the environmental impact of producing key materials, specifically steel, cement, and plastics, on atmospheric aerosol loading (AAL), a critical process affecting air quality and climate. By analyzing data from major global producers, including China, India, the United States, and Iran, over the period from 2012 to 2022, we explore how emissions from these materials contribute to air pollution. Our findings indicate that cement production is the largest contributor to AAL, primarily due to its significant sulfate emissions, which account for 35%–37% of global industrial aerosol loading. To better understand these dynamics, we introduce a novel model that integrates the production of bulk materials, aerosol precursor gases, and concepts of planetary sustainability. This model reveals a reverse J -curve pattern, suggesting that while industrial growth initially leads to increased emissions, effective policy interventions and technological advancements can result in a subsequent decline in aerosol loading. Furthermore, we propose a global mean aerosol optical depth threshold of 0.21 as a critical planetary boundary (PB) for AAL. Our research highlights the varying contributions of different countries to aerosol loading and emphasizes the importance of sustainability-oriented strategies. Key recommendations include transitioning to clean energy, enhancing manufacturing efficiency, and fostering international collaboration to mitigate the environmental impact of material production while remaining within PBs.