Global health burdens of plastics: a lifecycle assessment model from 2016 to 2040.

BACKGROUND: Quantifying human health impacts throughout plastics lifecycles can inform global action against pollution that promotes sustainability across environmental, economic, and health concerns. METHODS: We combined material flow analysis, using the Plastics-to-Ocean model, with lifecycle assessment (LCA) to quantitatively compare disability-adjusted life-years (DALYs) associated with plastics lifecycles, under different global consumption and waste management scenarios between 2016 and 2040. We estimated global health effects of greenhouse gases, particulate matter, and specific chemical emissions associated with plastics commonly found in municipal solid waste (approximately 64% of global plastics production), from their production, transportation, recycling, end-of-life fates, and those associated with illustrative alternative single-use materials and glass reuse systems. Direct health effects of exposure to chemicals during product use and microplastics and nanoplastics pollution were not included due to the absence of available inventory data. We conducted the LCA using Ecoinvent version 3.8 and 3.10 (cutoff) data and ReCiPe 2016 impact assessment method, updated with Intergovernmental Panel on Climate Change 2021 global warming characterisation factors. FINDINGS: We estimated a cumulative 83 million DALYs associated with business as usual (BAU) projections of the global plastics system (2016-40), mainly due to the health burdens of global warming, air pollution, and chemical toxic effect-related disease and premature mortality. Compared with BAU, reducing total global primary plastics production, combined with improving waste collection and disposal, increasing recycling, and replacing specific plastics with alternative materials and reuse systems reduced annual DALYs by 43% (46-23% in material substitution ratio sensitivity analyses) in 2040, but still indicated rising global health burdens over time. Reducing primary plastics production, without material substitution, was the most effective single lever for reducing emissions and alleviating associated health burdens. INTERPRETATION: Adverse health effects are associated with emissions throughout plastics lifecycles, particularly from production, though the non-disclosure of plastics chemical composition is severely limiting LCA capacity to inform effective policy. Deep reductions in primary production are needed in leading plastics transition roadmaps, with assessments that account for plastics' functions across sectors, including exposure and health impacts from plastics' use, from chemicals, microplastics, and nanoplastics, facilitated by mandatory transparency and reporting. Globally coordinated policy that addresses these upstream impacts through a full lifecycle approach is crucial to protecting human health. FUNDING: Innovative Methods and Metrics for Agriculture and Nutrition Actions programme, UK Foreign Commonwealth and Development Office, Bill & Melinda Gates Foundation, French National Research Agency and Region Occitanie.