The Queensland premier, Campbell Newman, has been forced to fend off attacks on the integrity of his government as new details emerged linking one of his ministers to a business figure involved in a controversial coalmine expansion.



Newman hit the election campaign trail on Tuesday with Ian Walker, who Guardian Australia can reveal took a donation from a board director of New Hope Coal before his election in 2012.

Walker, as the minister for science, information technology, innovation and the arts, subsequently oversaw the department which cleared levels of air pollution from uncovered coal trains in Brisbane before the expansion of New Hope’s Acland mine.

Walker was also acting minister for state development when he called

for public input on New Hope’s environmental impact statement for

Acland last year.

The state Labor leader, Annastacia Palaszczuk, has claimed that the Liberal National party government had opened the door to corruption and on Tuesday radio host Alan Jones renewed his attack on Newman over Acland.

Donor records show that New Hope director Bill Grant gave a $2,000 personal cheque to Walker’s campaign fund in October 2011.

The donation would have been secret under the LNP’s widely-criticised move to raise the threshold for declaring contributions from $1,000 to $12,400 last year.

The pollution study by Walker’s department was released to companies including New Hope a week before it was made public in 2013.

Walker, who appeared with Newman at a press conference on the Gold Coast announcing a new $60m tourism fund, left while refusing a request for interview from Guardian Australia.

In a statement later, Walker declined to explain the nature of his relationship with Grant but said all donations were “fully disclosed in accordance with the law”.

Walker said his office had no role in the pollution study, for which coal companies had paid $250,000.

Asked if those payments had created a conflict of interest, Walker said the decision to engage “the state’s top independent scientists shows a proactive role in ensuring clean air for Queenslanders”.

Palaszczuk at the Labor campaign launch suggested the LNP had paved the way for a return to the graft of “brown paper bag” politics in Queensland.

Newman said in response that there were “appropriate authorities that can deal with such things”. He accused Labor of running “a campaign about negativity and personality politics”.

“Why? They have no plan for Queensland, they don’t have the ticker to sort out the financial problems we inherited,” he said. “They certainly don’t know how to create jobs so they engage in this sort of thing.”

Newman repeatedly refused to say whether he had met Jones at his home before last election and promised to block the mine expansion.

A spokesman for Newman declined to comment on Walker and his relationship with Grant.

Jones has travelled to Queensland to run daily “election special” programs on 4BC radio, denouncing Newman as a “bully boy” and his government as the worst in Australia.

The decision to allow Acland to mine another 3m tonnes of coal a year was announced on the Friday before Christmas.

New Hope and its parent company, Washington H Soul Pattinson, donated more than $700,000 to the LNP at a state and federal level between 2011 and 2013.

Asked if New Hope’s donations influenced the government’s approval, Newman said: “I will not be commenting on Alan Jones.”

Asked by Guardian Australia if LNP officials had indicated whether the party’s donations had risen since it raised the secrecy threshold, Newman replied that he had “no idea”.

“You’ll have to ask them. I’m not involved,” he said.

Jones has also attacked the government over the energy minister, Mark McArdle, and the environment minister, Andrew Powell, accepting entertainment from New Hope in its corporate box at a Wallabies rugby game in Brisbane in 2013.

Activist group Clean Air Queensland said the Acland expansion would increase coal dust pollution in Brisbane.

Clean Air Queensland organiser Michael Kane said his tests showed emissions of particulate PM10 from uncovered coal wagons in Brisbane exceeded national safety levels tenfold, as often as 10 times a day.

Kane claimed the government study clearing the pollution levels by averaging emissions over 24 hours was “absolutely the wrong methodology”.

Walker said that methodology was “determined by departmental scientists exercising their independent professional integrity”.

QUT researcher Adrian Barnett said air pollution standards were “a political limit and shouldn’t be used as a health tool since no level of pollution is safe”.

New Hope’s chairman, Robert Millner, was called before the Independent Commission Against Corruption (Icac) in NSW last year over a donations controversy involving another Washington H Soul Pattinson subsidiary of which he was chairman, Brickworks.

Icac is due to complete its report this month on whether Brickworks’ donations to the Liberal party in NSW broke laws banning political contributions from developers.