Up to a third of the herbal medicine Ginkgo Biloba, sold in Australia, might be adulterated, or “spiked” according to recent Government tests.

But the Therapeutic Goods Administration appears to be doing little about it, and refuses to reveal the offending brand names.

Public Health expert Ken Harvey has been fighting the TGA to release these names for the past year, with no luck.

He says the TGA is too closely linked to business.

He's speaking here with 2SER's David Fanner.