Bismuth: Emissions
How lead and tungsten chains decide bismuth's footprint
How lead and tungsten chains decide bismuth's footprint What this tab covers The greenhouse-gas footprint of the commodity at a global level, split by lifecycle phase: extraction (or farming), refining and processing, movement, usage, and recycling or end of life. Intensities are per unit of product; the global total combines intensity with world output. Also covers other environmental impacts and the main levers to cut emissions. Emission intensity 58.9 t CO2e per t range not published; strongly dependent on allocation within lead and tungsten chains · cradle-to-gate, 2008 supply mix, economic allocation within the lead-zinc system Global emissions per year 0.94 Mt CO2e per year 2025 · 58.9 t x 16 kt (derived, indicative)Per t of refined bismuth (99.99%), cradle-to-gate. Intensity: Nuss & Eckelman 2014, PLoS ONE (ecoinvent 2.2 data, economic allocation, 2008 supply mix; value read from Fig. 2, indicative). Global total: Derived from Nuss & Eckelman 2014 and USGS MCS 2026.
Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | small allocated share of lead, tungsten and zinc mining | – | host-ore mining and concentration | By-product allocation leaves most mining burden with the host metal | Nuss & Eckelman 2014 (qualitative) |
| Refining / processing | dominant: lead smelting share, debismuthising with calcium and magnesium or anode-slime treatment, refining to 4N | – | coal and coke in lead smelting, electricity for electrorefining | Nuss & Eckelman report purification and refining dominate for bismuth | Nuss & Eckelman 2014 |
| Movement | negligible per tonne | – | container freight of small lots | Not material | Qualitative |
| Usage | no direct emissions | – | pharmaceuticals, cosmetics, alloys | Not applicable as a direct emission | Qualitative |
| Recycling / end of life | little recovery: EU end-of-life recycling input rate 0%; alloy scrap up to 10% of US use | – | remelting of fusible alloys and brass scrap | Bismuth in medicines and cosmetics is dissipated | EU CRM 2023; USGS MCS 2026 |
Other environmental impacts
Tied to lead smelting, with its lead and SO2 emissions where controls are weak; tungsten mining in Hunan and Jiangxi has caused local water pollution.
Levers to cut emissions
- Cleaner, lower-carbon lead smelting (e.g. oxygen bath smelting with acid plants)
- Recover bismuth from brass and solder scrap rather than diluting it
- Add recovery circuits at non-Chinese lead smelters, shortening supply chains
- Low-carbon power for electrorefining
India
India produces no bismuth and imports about 475 t a year ($5.6 million in 2024) for chemicals and alloys, so its footprint is embedded in Chinese lead and tungsten smelting.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.