Cocaine traces have been found at the European Parliament in an inquiry by one of Germany's main broadcasters.
The results suggested cocaine was in regular use in the areas tested
The Sat-1 channel sent reporters to take 46 swabs from toilets and other public areas of the Brussels buildings. Nearly all tested positive for cocaine.
A European Parliament spokeswoman said cocaine abuse was not a problem among staff working at the buildings.
A professor who analysed the samples said the amounts found were too great to have been carried in on clothing.
"It simply reflects the fact that cocaine was brought in there," Professor Fritz Sorgel of the Institute for Biomedical and Pharmaceutical Research in Nuremberg (IBMP) told the BBC News website.
"The amount was too high and found in too many spots. It shows it was brought in deliberately."
However, he said the results were not so surprising given the widespread use of cocaine in society at large.
As the buildings are cleaned regularly, it appeared that cocaine had been used recently in the places where the traces were found, Mr Sorgel said.
A total of 41 of the reporters' swabs tested positive for cocaine.
European Parliament spokeswoman Marjory van den Broeke said the findings came as a complete surprise, insisting that cocaine use was not a problem among staff working at the building.
"It seems the findings are in line with findings in other public buildings," Ms Van den Broeke told the BBC News website.
"It is not a problem we are aware of at all."
But given the way the tests were carried out - with reporters coming in and taking swabs in toilets to be tested at a later stage - it was difficult to say how conclusive the tests could be, she said.
The parliament may look into whether the testing was legal as it was performed without its consent or knowledge.
The broadcaster conducted the same experiment in the German parliament with similar results five years ago.
Prof Sorgel made it clear cocaine was not found in all public places - not in German high schools for example.
"Many sites have no cocaine. It's not everywhere," he said.
The producer of the AKTE 05 TV show, Ulrich Meyer, said consumption of cocaine was a problem which pervaded all of society - "bigger than many politicians are willing to believe".
"We do not wish to point our fingers at any individuals or professional groups," he said, pointing out that the European Parliament building was open to the public.