Lithium is a critical material for the energy transition, but its mining causes significant environmental impacts that will intensify due to surging global demand. Here, we conduct a mining site-specific environmental impact assessment of lithium on a global scale, focusing on greenhouse gas (GHG) emissions, water use, and land use. We then track the production and international trade flows of all lithium-containing commodities to assess how lithium mining impacts are distributed across global supply chains. Results indicate that environmental impact intensities of battery-grade Li