ABOUT 200 workers at an engineering firm at Walvis Bay allegedly had upset stomachs after drinking "expired cooldrinks" at a company function at Dune 7 on Saturday.

The party caterer described the alleged diarrhoea as a case of "sour grapes" because the workers were limited to one beer each, and were not allowed to trade their soft drinks for more beer.

The Namibian received a complaint that the workers were "poisoned" by their manager, who allegedly gave them "expired cooldrinks and beer".

"[This manager] is busy poisoning the workers. We were about 300 workers at the party. Now about 200 workers have diarrhoea just because they drank expired stuff," one worker said.

A company source said they were not aware of so many workers being sick after the party; in fact, it was the first time they had heard of it.

The source said that the function - to celebrate a successful project - was catered for by a local business and that the company was not responsible for providing the drinks.

An agreement that each worker was allowed one beer and two soft drinks was apparently not welcomed by all, with some partygoers unsuccessfully trying to swap their soft drinks for more beer.

The caterer said it was impossible that so many people could have become sick.

According to him, there were only about 200 workers at the party, and he confirmed the agreement with the company that each worker was allowed one beer and two soft drinks.

He admitted that one of the workers did in fact bring to his attention an expired soft drink.

"I immediately removed the expired cans and replaced them with fresh stock. I also don't like expired stock. That was an exception since I always keep fresh stock but sometimes a few expired items will slip through. It would only have been a few expired cooldrinks that were mistakingly handed to the workers, but not so many as to make 200 sick," said the caterer.