The food we eat, the air we breathe: a review of the fine particulate matter-induced air quality health impacts of the global food system

Abstract

The global food system is essential for the health and wellbeing of society, but is also a major cause of environmental damage. Some impacts, such as on climate change, have been the subject of intense recent inquiry, but others, such as on air quality, are not as well understood. Here, we systematically synthesize the literature to identify the impacts on ambient PM _2.5 (particulate matter with diameter ⩽2.5 μ m), which is the strongest contributor to premature mortality from exposure to air pollution. Our analysis indicates that the life-cycle of the global food system (pre-production, production, post-production, consumption and waste management) accounts for 58% of anthropogenic, global emissions of primary PM _2.5 , 72% of ammonia (NH _3 ), 13% of nitrogen oxides (NO _x ), 9% of sulfur dioxide (SO _2 ), and 19% of non-methane volatile organic compounds (NMVOC). These emissions result in at least 890 000 ambient PM _2.5 -related deaths, which is equivalent to 23% of ambient PM _2.5 -related deaths reported in the Global Burden of Disease Study 2015. Predominant contributors include livestock and crop production, which contribute >50% of food-related NH _3 emissions, and land-use change and waste burning, which contribute up to 95% of food-related primary PM _2.5 emissions. These findings are largely underestimated given the paucity of data from the post-production and consumption stages, total underestimates in NH _3 emissions, lack of sector-scale analysis of PM _2.5 -related deaths in South America and Africa, and uncertainties in integrated exposure-response functions. In addition, we identify mitigation opportunities—including shifts in food demand, changes in agricultural practices, the adoption of clean and low-energy technologies, and policy actions—that can facilitate meeting food demand with minimal PM _2.5 impacts. Further research is required to resolve sectoral-scale, region-specific contributions to PM _2.5 -related deaths, and assess the efficiency of mitigation strategies. Our review is positioned to inform stakeholders, including scientists, engineers, policymakers, farmers and the public, of the health impacts of reduced air quality resulting from the global food system.

Keywords

• fine particulate matter
• global food system
• air quality
• emissions
• premature mortality
• mitigation