The radioactive substance, most probably cesium-137, mixed with scrap metal meant for export from Georgia's Black Sea port of Batumi had been used for industrial processes and would not pose threat to public health, Georgian authorities said on Wednesday.

The Georgian energy ministry said that the radioactive substance found on Tuesday at the port was being shipped in a special container to the Georgian capital Tbilisi for further examination to identify its origin of source.

The authorities added that the port, partially closed down on Tuesday, had been rendered harmless already.

From time to time, cesium-137 is found from within scrap metal.

One notable example was the Acerinox incident of 1998, when the Spanish recycling company Acerinox accidentally melted down a mass of cesium-137 that came from a gamma-ray generator.

Cesium-137 encased in metallic casings can be mixed up with scrap metal on its way to smelters, resulting in production of steel contaminated with radioactivity.