A fifth case of black lung in Queensland coal workers has been confirmed, leading some to suggest there could be many more.

CFMEU Queensland mining and energy division president Steve Smyth says the diagnosis came after the worker submitted documents for a worker's compensation claim.

His X-rays and scans were sent to the United States for further examination, and it was there that the potentially deadly condition was revealed.

“This actually now, unfortunately, may be the tip of the iceberg,” Mr Smyth told reporters.

“We believe that, whilst we welcome the review of the health scheme, that will not go far enough.

“There needs to be a public inquiry with an independent commissioner with public submissions to get to the bottom of this... [and the question of] how we can have such a terrible disease that people thought was eradicated, suddenly be back and maybe worse than ever.”

The Queensland Department for Natural Resources and Mines has confirmed the case, but there is word that as well as the five confirmed cases of black lung so far, there are five more ‘potential cases’ waiting on the results of tests.

Mr Smyth said it would be easier to spot cases of black lung if Australia had enough medical experts with expertise to identify the disease from X-rays and other scans.

“Whilst we have trained and qualified radiologists here, we don't have people that can read these X-rays to a B-Reader standard,” Mr Smyth said.

“They say they will have, but they don't.

“That has been proven by the number of cases that have all been confirmed in the United States [after Australian X-rays were sent there] or have been confirmed by a lung biopsy, which is a very invasive procedure.

“It's a terrible state of affairs when here in Queensland in the 21st century we don't' have qualified people that can read these X-rays, for a disease that has been around since the 18th and 19th centuries.”

Monash University Professor Malcolm Sim has told the ABC that it is too early to say that the current set of cases are ‘the tip of the iceberg’.

Professor Sim also rejected the union’s claim that there is a lack of skilled radiologists to identify black lung cases.

“I think we do have a well-trained group of professionals in this country,” he said.

“Perhaps what is needed is a greater awareness of the dust exposure in coal mines and also look at the ways the medical monitoring is reported back to the mines department.”