Thallium: Emissions
Why thallium's carbon number could not be found
Why thallium's carbon number could not be found 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.Per kg of thallium metal; cradle-to-gate, by-product of zinc-lead smelting. Intensity: Nuss & Eckelman 2014 (PLoS ONE) include thallium as a Pb-Zn by-product, but the per-kg value could not be retrieved. Global total: Nuss & Eckelman 2014, PLoS ONE 9(7): e101298.
Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | allocated from zinc, lead and copper mining | – | diesel and electricity at host-metal mines | By mass or value allocation, thallium's share of mining burdens is very small | Nuss & Eckelman 2014 |
| Refining / processing | not published | – | roasting of sulphide concentrates; leaching flue dust; precipitation and electrolysis of thallium | Refining dominates impacts for most metals (Nuss & Eckelman 2014) | Nuss & Eckelman 2014; USGS MCS 2026 |
| Movement | negligible | – | small air and road consignments under hazardous rules | About 10 t a year worldwide | USGS MCS 2026 |
| Usage | not applicable directly | – | no combustion; detectors, optics, superconductors, medical imaging | No enabling emissions quantified | USGS MCS 2026 |
| Recycling / end of life | none | – | USGS reports no recycling | Toxic waste must go to controlled disposal | USGS MCS 2026 |
Other environmental impacts
Toxicity is the key environmental issue, not carbon. Thallium enters the body by skin contact, ingestion or inhalation of dust and fumes. Smelter emissions and coal combustion are main sources of environmental thallium; the US EPA limit in drinking water is 2 ppb.
Levers to cut emissions
- Capture thallium from smelter flue dust instead of releasing it to air or tailings
- Substitute technetium-99m for thallium-201 in cardiac imaging (already under way)
- Replace thallium heavy liquids with non-toxic tungsten compounds for mineral separation
India
India reports no thallium recovery at its zinc and lead smelters and imports small amounts, so no Indian footprint is published (USGS MCS 2026).
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.