Tai Po drug maker Europharm was inspected just four days before the announcement that one of its products had been found to be contaminated with a potentially fatal fungus. Yesterday health authorities were urged to step up inspection of drug manufacturing plants. The drug, allopurinol - used primarily to treat gout but also given to leukaemia patients - has been linked to the deaths of five patients at Queen Mary Hospital. The fungus triggers an infection that can kill people with weak immune systems, such as leukaemia and lymph cancer sufferers. Benjamin Kwong Yiu-sum, president of the Pharmaceutical Society, said there was room for improvement in the way the Department of Health inspects manufacturers. 'The department should enhance checks, for instance on the environment, and check samples rather than just looking at documents,' he said. But the department's chief pharmacist, Anthony Chan Wing-kin, said: 'Inspection ... [involves] a thorough review of all the activities related to the manufacturing, quality control and sale of medicine.' Europharm Laboratories has been told to stop the production and sale of its 700 products pending the outcome of investigations into how the contamination occurred. On Friday, the Department of Health took away for analysis samples of all products made at the plant. It said yesterday that it was the first time in recent years that drugs had been found contaminated with the fungus, Rhizopus microsporus. The allopurinol pills contained 100 times the permitted level of the fungus, which occurs naturally. Mr Chan said the department inspected all 25 local manufacturers of western medicines twice a year. None had been found to have breached World Health Organisation guidelines since 2002. Mr Kwong said the department should employ more inspectors.