The alert, issued by the Fraser Health Authority, urges people who were clients of Tung Sheng Wu, also known as David Wu, to get a blood test to determine if they were exposed to blood-borne viruses.
The College of Dental Surgeons of B.C. said it hired private investigators to conduct surveillance on Wu's Burnaby, B.C., home after it received a complaint.
College registrar Jerome Marburg said the man isn't a dentist, isn't registered to practice in B.C. and there was no indication he was competent to practise.
"We know we have evidence showing a range of practice from fillings and extractions to orthodontics," he said in an interview.
Marburg said the concern now is for patients, because Wu's operation didn't come close to the hospital-like cleaning regime that B.C. dentists are instructed to maintain.
"The evidence certainly shows not a very clean establishment."
College president Dr. Peter Stevenson-Moore said in a news release material seized from Wu's home didn't come close to standards set for patient care, "which leads us to believe that he has put his clients' health at risk for his own gain."
The Fraser Health Authority said letters are being sent out to clients of their potential exposure and telling them to contact pubic health to get tested.
Marburg said they believe Wu targeted the Chinese-Canadian community and most of the man's records for 1,500 clients were written in Cantonese.
This isn't the first time the college has had dealings with Wu.
In 2003, the college obtained a court injunction ordering the man to stop his underground dental practice.
At the time, Marburg said Wu was contrite.
"He recognized that he was doing wrong, promised not to do anything like that again and we had every indication that he was, in fact, leaving the country."
Instead, a complaint from an unhappy client led the college to investigate Wu once again. On May 29, RCMP and college investigators entered Wu's home with a search warrant.
The college will be in court next week asking for a renewed injunction and a contempt order against the man for breaking the original injunction.
Marburg said such a contempt order could mean jail time, but he didn't want to speculate what a judge might decide.
"We think this guy is on the high end of the scale and we're going to make arguments for a very strong remedy, the court can decide that."
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