This study measured technology-critical elements, including gallium, in bottom sediments of a Polish river that drains a zinc and lead mining area. Gallium reached 25.6 mg/kg. Most of it was locked in the residual mineral fraction.
Key numbers
- Maximum sediment gallium 25.6 mg/kg at site BP3. Average 11.8 mg/kg (Results and abstract). 11.8 mg/kg is 11,800 µg/kg.
- Gallium was mainly in the residual fraction. The maximum share in fraction F3 (amorphous and poorly crystalline iron and aluminum hydroxides) was 7 percent. The largest share in fraction F4 was 23 percent, at BP5 in October (Results).
- The paper cites a Silesia-Cracow range of 1.50 to 177 mg/kg from other work (Results; secondary).
Methods (brief)
Sediments were digested with nitric acid, hydrogen peroxide, and hydrofluoric acid and analyzed by ICP-MS. Mobility was assessed by a five-step sequential extraction. Sites ran from Chrząstowice to Sosnowiec.
Evidence fitness
Supports measured gallium in these mining-affected sediments and its low share in the more mobile fractions. Does not support a food or drinking-water concentration. Sediment gallium is upstream context.
Limitations
One river system. Contamination indices in the paper rate several elements, including gallium, against background values taken from other studies. Those index scores are not repeated here as health evidence.
Related evidence
Update history
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