PARKING your car at the World Trade Centre could be dangerous to your health, according to tests carried out at the Causeway Bay building. The tests showed dust levels in the basement car park more than four times the safety limit. Exposure to such levels can cause respiratory and cardiovascular illnesses. The centre, bought by Sun Hung Kai Properties for $2.2 billion in February last year, is being extensively renovated. But the 176-space car park has stayed open despite the work. Tests commissioned by the Sunday Morning Post and carried out by the independent EHS Consultants Ltd revealed an average of 730 micrograms of dust per cubic metre of air. The Government's recommended limit is 180 mcg. The work, due to finish by the middle of next year, is funded by Sun Hung Kai, but the car park is operated by Wilson Parking. And the owners said it was Wilson's decision to keep it open. Wilson, which operates car parks throughout Hong Kong, said yesterday there was no danger to customers, who pay a minimum $50 to park. ''We hope the driving public appreciate the situation is caused by works outside our control,'' said operations manager Kevin Mo Kam-tong. ''We have a responsibility to keep the car park open for public convenience, especially tenants of the World Trade Centre.'' They had received a few complaints, mainly about cleanliness rather than air quality and offered customers car covers and a complimentary cleaning service. ''We do not consider the car park to be a danger, just a little inconvenient at the moment,'' Mr Mo said. The Government accepts Hong Kong's car parks are polluted and some pose a health risk, but it says a lack of resources prevents it bringing in legislation to deal with the problem. A 1992 probe by the Environmental Protection Department found half of the 38 basement car parks tested exceeded safety guidelines. Among the dangers were alarming levels of carbon-monoxide, enough to cause nausea, dizziness and loss of breath. According to the Sunday Morning Post tests, carbon-monoxide levels at the World Trade Centre car park were within safety limits.