Diverting household and commercial food scraps from landfills toward composting and anaerobic digestion can cut greenhouse-gas emissions and support a circular bioeconomy. But the transition isn’t automatically clean: recycling can shift pollution pathways by altering nutrient runoff into waterways and by carrying contamination—especially plastic packaging—into soil. Now, a new US-wide analysis uses integrated mass-balance modelling alongside life cycle assessment (LCA) to quantify both the gains and the risks of “organics recycling” at national scale.
The study compares today’s landfill-dominant food-waste system with hypothetical future scenarios that expand composting and anaerobic digestion. Researchers track where key outputs go—methane emissions avoided when waste is prevented from decomposing anaerobically in landfills, and where nitrogen (N) and phosphorus (P) ultimately end up once digestate and compost are land-applied. They also model plastic movement through recycling streams, focusing on whether packaging plastics could accumulate in agricultural soils over time.
Results indicate a dramatic climate advantage. Nationwide implementation of organics recycling could reduce the climate impact of US food-waste management by an estimated 89–99% compared with current landfill-dominant practices. The magnitude reflects both reduced landfill methane and the altered energy and materials balance captured by LCA.
The nutrient picture is more nuanced but still strongly improved overall. Relative to current practice, organics recycling could lower associated nitrogen loading to downstream waterways by roughly 49–54%. Phosphorus loading would fall even more sharply, by about 78–98%, suggesting that shifting treatment away from landfilling changes nutrient transport and bioavailability along the food-waste-to-water chain.
Yet environmental caution remains. The modelling suggests that land application of food-waste-derived composts and digestates would offset less than 2% of annual US mineral nitrogen and phosphorus fertilizer consumption. In other words, the agronomic substitution benefit is limited, even though recycled products could meaningfully change runoff patterns.
The most viral warning concerns plastics. Without innovations that redesign food packaging to reduce plastic leakage and contamination in recycling inputs, the analysis estimates plastic releases of around 20,000 tonnes per year into US agricultural soils. That quantity could represent a long-term accumulation risk, especially for persistent polymers that escape pre-treatment sorting.
Together, the findings frame organics recycling as a climate and nutrient pollution winner with a contingency plan: nutrient impacts improve, but soil plastic burdens may rise unless contamination is engineered out of the system. The study underscores that “circular” only holds when waste management, product design, and agricultural pathways are aligned.
Subject of Research: Food waste recycling in the USA; climate, nutrient pollution, and plastic contamination risks
Article Title: Food waste recycling in the USA can reduce climate and nutrient pollution impacts yet risks plastic accumulation in soils.
Article References: Porterfield, K.K., Schambura, M.N. & Roy, E.D. Food waste recycling in the USA can reduce climate and nutrient pollution impacts yet risks plastic accumulation in soils. Nat Food (2026). https://doi.org/10.1038/s43016-026-01396-z
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s43016-026-01396-z
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