It is understood that some harbour hazardous chemicals which could present a danger to transatlantic vessels on the main shipping lanes.
The containers slipped off German-registered ship MSC Flaminia, which caught fire on Jul 14. It caused an explosion that forced the crew to abandon the ship.
Salvage operations were under way yesterday as some of the containers were towed into Castletownbere, West Cork, by a tug boat.
The Hamburg-registered ship had originally been on its way from Charleston in the US to the German port of Bremenhaven.
The 85,823-tonne vessel was carrying 2,876 containers, 149 classed as dangerous goods.
One crewman died and another is missing, presumed dead, following the incident on the Atlantic. The surviving 24 crewmen were rescued from a lifeboat.
The ship started listing and some of its containers fell into the sea, about 1,600km from land.
The MSC Flaminia remained listing until authorities in Britain, France, Belgium, and the Netherlands cleared it for passage to be towed through the English Channel. It recently arrived in the German port of Wilhelmshaven.
Now, some of its containers are appearing off the south-west coast and floating into the Atlantic’s main cargo shipping lanes.
The Atlantic Towage & Marine Ltd-owned tugboat The Ocean Bank, skippered by Castletownbere-based Sean Harrington, was asked by the ship’s insurers to recover some of the containers yesterday.
“They were about 80 miles south-west of the coast when we located them and towed them back,” Mr Harrington said. “The three we recovered were empty.”
He said it was possible the tug boat would be sent out to bring in others in the days ahead.
“There were a good lot of them floating into shipping lanes and that could be a cause of concern for other vessels,” he said.