According to the pecuniary interests register at Leichhardt Council, where Mr Parker is mayor, he was marketing manager of Cat Media during that period.

A review of TGA decisions shows scathing comments, including this about the cholesterol treatment Cholestaguard: ''Advertisements which were unbalanced and exploited the lack of knowledge of consumers, and could bring about fear of distress among consumers''.

A FatBlaster ad was criticised for ''misleading consumers into thinking that the product had been used successfully by well-known celebrities (just like Catherine Zeta-Jones and Posh Spice)''.

The company was also found to have used staff members to write supposedly independent reviews of products. Cat Media claimed falsely, according to the TGA, that its HangOver STOP could ''stop a hang over''.

Mr Parker denied that he was responsible for any of the breaches.

''It wasn't my role to be putting together advertising and copywriting, I was positioning the stuff in pharmacies,'' Mr Parker told The Sun-Herald.

''There were many directors. I had a small team of people doing things like graphic design. Yes, I've worked in the private sector, I'm not a union hack.''

Mr Parker left Cat Media in 2006.

Ms Firth, who was recently rocked by the drug-related arrest of her husband, Matthew Chesher, holds Balmain by 3.7 per cent.

A Labor Party source said: ''This is a tough contest for Labor, greatly helped by the fact that our opponent appears to be a snake oil salesman.''