Health experts have sounded the alarm over the "immense power" the alcohol, gambling and tobacco industries exercise in Australian politics.

A new study published in the Drug and Alcohol Review found these industries collectively donated at least $12 million to Australia's major parties from 2006 to 2015.

The alcohol and gambling industries in particular made substantial donations "to influence decisions in the short term and build relationships over the long term", the study said.

It found donations from these sectors increased "substantially" during debates about alcohol tax and gambling law reform.

Alcohol industry donations increased in 2008 and 2009, when the alcopops bill was being debated and gambling industry donations to Labor peaked in 2008 and 2009 during a major inquiry into gambling.

It also found alcohol industry donations "spiked" ahead of elections.

Labor banned tobacco donations in 2004 and the Liberals followed suit in 2013. But the Nationals and some minor parties have not followed suit.

AAP

'If they donate $100,000, they've bought you'

The researchers conducted interviews with "politicians, ex-political staffers and other key informants" as part of the study.

"If someone donates $1000, they support you. If they donate $100,000, they've bought you," one politician who remained anonymous said.

The Drug and Alcohol Review

And one ex-politician said "there's no doubt that if someone makes a significant donation to your campaign or to your political party, then you tend to look fondly towards them".

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Another politician told researchers that Liberals and Labor reached out to James Packer when gambling reforming was being mooted.

"Packer made it absolutely clear to them that $1 maximum bets was completely and utterly unacceptable. It could not be allowed, and … then-Prime Minister Julia Gillard and then-leader of the opposition Tony Abbott both refused the $1 maximum bet proposition."

The Drug and Alcohol Review

Ban all donations?

SBS News talked to Professor Kypros Kypri of the University of Newcastle, one of the authors of the report.

Professor Kypri said this is "a problem of Liberal, National and the Labor parties ... [But] the Liberal party receives the bulk of the donations, more than half."

He said the most shocking element of the study was how "poorly regulated political donations are" in Australia.

Currently, donations under $13,800 do not have to be declared, which Professor Kypri said is "ripe for abuse".

"If you got 20 donors who all have a common commercial interest ... They can each put in just under the limit and suddenly you have a quarter million dollars with no record," he said.

"The public won't be able to know. The political party that receives it doesn't have to tell anyone."

He said the study also showed that these industries seem to have perfected the art of "small money lobbying", which involves "identifying rising stars and funding them ... Then they become beholden over the long term".

"They have immense power," he said of these industries.

Concerned about the "undue influence on public policy", the study recommended, "banning corporate donations ... to safeguard the integrity of public policy-making".

A 'fungating cancer' on democracy

Australia ranked 13th out of the 180 countries in the Corruption Perceptions Index in 2017, but its ranking is falling, with the study partly blaming "an undue influence on politicians of corporate actors".

In June, a Greens-dominated inquiry into donations recommended bans on donations from developers, banks, mining companies and the tobacco, liquor, gambling, defence and pharmaceutical industries.

It also called for the continuous real-time disclosure of donations to the AEC, something already occurring at a state level in some jurisdictions.

"The big money that is pouring into our parliament from vested interests is a fungating cancer on our democracy," the party's leader Richard Di Natale said earlier this year.