Two men are dead and two are fighting for their lives in hospital after drinking a home-distilled 'grappa' on Queensland's Granite Belt.

The men are believed to have methanol poisoning after drinking the Italian grape-based spirit known as grappa.

Authorities were alerted on Sunday morning but could not revive a 21-year-old man who died at a house at Ballandean.

They later received another emergency call from the same address.

A 30-year-old man was rushed to Toowoomba hospital yesterday in a critical condition where he died this afternoon.

The two others, aged 21 and 26, remain in intensive care in Brisbane's Princess Alexandra Hospital.

Health Minister Lawrence Springborg says it is an extraordinary and tragic event.

"If steps need to be taken to pursue anyone or any individuals, no doubt proper authorities will do that," he said.

"There will also need to be some consideration as to what risk factors were involved here and what might be able to or need to be done to protect people in the future.

"When it comes to home brew, it's not without some degree of risks and the immediate concern needs to be here to make sure the young people are able to be assisted to the road for recovery."

Mr Springborg says investigations are being conducted by police and Queensland Health.

A report is being prepared for the coroner.

Distilling alcohol 'complex'

Professor Paul Haber, the head of Drug and Alcohol Services at the Royal Prince Alfred Hospital in Sydney, says distilling alcohol is a complex process.

"The backyard still involves fermentation, which generates a large range of biological products," he said.

"Then there's a distillation process and that is supposed to separate the alcohol and certain other chemicals and concentrate the alcohol component.

"The risk is that if the distillation process is not done correctly, then the wrong products will be extracted.

"The key toxic product that can be distilled in that way is methanol."

Professor Haber says methanol is hard to taste or smell, and when it is digested it turns into formaldehyde.

He says distilling spirits is more risky than home-brewing beer, but it is rare for people to become seriously ill from drinking homemade alcohol in Australia.

Professor Haber says he sees about one case every five years.

"In our country, Australia, where you can buy legally prepared alcohols so very, very cheaply, there's not a major economic incentive to get home brew," he said.

"I think most people are doing it because it's a hobby and they like it rather than because it's the cheapest way to get alcohol.

"In other parts of the world, the homebrew approach is actually the cheapest way to get alcohol and it's much more widespread."

'Risky and dangerous'

Methanol poisoning is more common in places such as Indonesia.

Nineteen-year-old Perth man Liam Davies died early this year after drinking cocktails laced with methanol off the coast of Lombok.

Perth rugby player Michael Denton died from methanol poisoning in Bali in September 2011.

Professor Haber says the death in Queensland should be a warning to Australians who distil their own spirits.

"It is a risky and dangerous practice and I would be advising people against doing it," he said.