Britain’s food standards regulator is investigating why the company did not tell authorities earlier about a contamination incident at one of its factories in January.
British confectioner Cadbury Schweppes defended the safety of its products despite the recall of 1 million chocolate bars after finding traces of salmonella contamination.
Cadbury said a batch of chocolate was contaminated with waste water from a leaking pipe at its factory in Marlbrook, western England, in January. The company said it had rectified the problem and was withdrawing the products "purely as a precautionary measure."
The Health Protection Agency said it was too early to say whether there was a link between the chocolate and an outbreak of 45 cases of the rare Montevideo strain of salmonella over the last four months.
Hugh Pennington, a bacteriologist at Aberdeen University in Scotland, said even tiny amounts of salmonella in chocolate could cause illness.
"The fat in chocolate actually preserves the salmonella from the normal intestinal defences, so you don’t have to eat very many salmonellas to get infected," Pennington told the BBC. "It’s about a thousand times less than if you’re eating it from traditional sources like meats."