Landfill manager SITA has applied for a planning amendment so it can accept category A soil - the most hazardous kind - at the landfill until 2022.

The state health department conducted the study over the past 12 months in response to concerns from residents and the Casey and Greater Dandenong councils.

Residents' concerns relate to possible increases in the occurrence of cancer and birth defects in people living near the Taylors Road landfill.

In its study, the health department compared cancer rates and birth defects in a four-kilometre radius around the landfill with the rest of Melbourne.

Senior medical adviser Simon Slota-Kan said the numbers were largely the same in each.

"You'd have to have much higher rates, up to 10 or 20 times the rest of Melbourne," he said.

An Environment Protection Authority air monitoring study also found pollutants from the landfill and other industrial activity in the area posed no health risks.

SITA's state general manager David Fyfe said the results were as he expected.

He said the site was heavily regulated and all waste was rendered immobile by the time it arrived, so staff weren't even required to wear safety gear while handling it.

"We didn't believe the landfill had any effect on the community," Mr Fyfe said. "We hope those fears are put to rest."

RATWISE secretary Jani Breider said the results did not reflect what was happening.

"I know from my neighbour, the frequency she goes to funerals of people who have died of cancer, who either lived in Dandenong South or had in the past," she said.

"Yes, they've got the results of the health study, but it doesn't fit with what is actually happening in the community."

Ms Breider said a study needed to focus on a smaller pocket of residents in the area bordered by the Dandenong Bypass and Dandenong-Frankston Road, through to the Dandenong Creek.

RATWISE president Thelma Wakelam said it was now up to residents in that area to push their case - "unless they come forward and push this, it won't go any further".

The category A waste application by SITA is awaiting rezoning approval from Planning Minister Matthew Guy and will then be assessed by the EPA, which will later decide to grant or refuse works approval.