The ABC’s chief said the public broadcaster had not identified a new Brisbane headquarters before a report into breast cancer was released.

Union officials meanwhile remain concerned Brisbane journalists and producers will continue working out of different locations under difficult conditions.

ABC staff abandoned the ageing site at Toowong, in the city’s inner-west, shortly before Christmas last year after an independent panel of experts headed by Professor Bruce Armstrong found the breast cancer rate there was up to 11 times higher than among the general working community.

Twelve women who worked at the riverside Toowong office have been diagnosed with breast cancer in the past 11 years, including eight who work in the newsroom.

ABC television staff returned to work on Dec 27 at a temporary studio based at the Network Ten premises at Mount Coot-tha while radio staff have begun broadcasting from a specially fitted out van in a Toowong carpark.

ABC managing director Mark Scott defended the response to the cancer cluster and said the organisation had to move swiftly once the cluster was confirmed by Prof Armstrong.

But he admitted the ABC had not had a new building in mind when the report came out.

“If you’re asking me whether in fact we took out a long-term lease in the prospect that this Armstrong report would find what it found, no we didn’t,” Mr Scott told ABC Radio.

“But did we make contingency planning so that we would continue to remain on air and provide local broadcasting and services to the people of Brisbane? Yes we did.”

The ABC would also be moving rapidly to set up its new building, once a suitable site was found.

“We are confident that when we find the right new location for us, that we will be able to fast-track that,” Mr Scott said.

Other ABC sites around the country are also set to be examined with Prof Armstrong to advise if there are any health concerns.

But Media Entertainment and Arts Alliance assistant federal secretary Mark Ryan said a site had to be found as a matter of urgency, despite the tight Brisbane commercial real estate market.

“They need to find sooner, rather than later, a site where they can actually perform their work properly,” Mr Ryan said.

“As far as we are concerned, the current situation cannot continue for any period of time.

“It is just unsustainable from a professional level and a workplace level.”