Shifting Protein Sources to Reduce Groundwater Nitrate Contamination: Insights from the U.S. Meat Market

Meat production is a major contributor to global environmental degradation, including groundwater nitrate contamination driven by intensive fertilizer use and manure production. This study explores the environmental implications of substituting conventional meat products (beef, poultry, and pork) with alternative protein sources—plant-based, insect-based, and cultured meat—using the U.S. meat market as a baseline. Employing an eXtreme Gradient Boosting (XGBoost) model, we quantify the risk of groundwater nitrate exceedance and compare resource requirements such as fertilizer, water, and land use for conventional and alternative proteins.

Results indicate that a 10% substitution of meat protein with alternatives reduces fertilizer use by 3.4%, manure production by 10.7%, and water usage by 4.5%, leading to a 20% reduction in groundwater nitrate exceedance risk. Plant-based alternatives show the lowest environmental impact, while insect-based options demonstrate high feedstock efficiency. Cultured meat, despite its potential, currently exhibits higher resource demands due to production constraints. The study further highlights regional variations in substitution effects, driven by agricultural practices and climatic factors.

These findings underscore the environmental benefits of transitioning to sustainable protein sources, providing actionable insights for achieving Sustainable Development Goals (SDGs) related to water quality, food security, and climate resilience. This shift not only reduces environmental risks but also ensures the sustainable management of groundwater resources.