NSW Premier Gladys Berejiklian labelled a hypocrite over smoke stacks backflip

The NSW premier has been labelled a hypocrite over her position on unfiltered motorway smoke stacks, with claims she is putting the health of thousands of school children at risk.

9NEWS has uncovered a 2008 speech to NSW parliament where a critical Gladys Berejiklian slammed the then Labor Government for proposing unfiltered smoke stacks for the Lane Cove Tunnel.

"World's best practice is to filter tunnels," Ms Berejiklian said at the time.

"Why won't they (Labor) allow people sleep at night, knowing their children aren't inhaling toxins that could jeopardise their health now or in the future?"

It is understood Ms Berejiklian currently has plans for at least eight unfiltered smoke stacks around proposed projects like the Iron Cove link in Rozelle, the Western Harbour Tunnel, Northern Beaches Tunnel and F6.

At least nine primary and high schools are near these proposed stacks.

"All we are asking for is what we feel is fair and right. I don't think anyone can argue children's health shouldn't come first," Sakia Lo from Rozelle said.

The Opposition says this proves Ms Berejiklian has backflipped on her original position.  

"She can't say one thing before she comes to government and do another when she is premier," Labor MP Prue Car said.

The Liberals pledged $176 million to filter stacks in a pre-election promise in 2007. 

Norway, Japan, Spain and Hong Kong are among countries that do employ filtration on ventilation stacks for long tunnels.

In 2008, Ms Berejiklian championed the work of Dr Ray Kearney, a University of Sydney professor who advocated in favour of filtration.

Dr Kearney, who has since retired, told 9NEWS he has maintained his view that unfiltered particulate emissions pose a grave health risk and will create high-concentration "hotspots".  

The premier maintains these proposed stacks have not been confirmed and the routes for the tunnels are still being finalised.

"There's no doubt communities should be concerned about ventilation stacks. I was (concerned) in my community," Ms Berejiklian said today.

"I want assure everybody that before we would even proceed down that path there will be extensive community consultation, lots of options."

NSW Chief Scientist, Professor Mary O'Kane, found in a July 2014 Tunnel Air Quality report that non-filtration is not harmful.

"Emissions from well-designed road tunnels cause a negligible change to surrounding air quality," the report read.

"There is little to no health benefit for surrounding communities in installing filtration."

The Chief Scientist is currently updating advice for future projects.

Planned sites of smokestacks near schools and childcare centres:

Lilyfield Rd, Rozelle

Victoria Rd, Rozelle

North Sydney Bowling Club

Serpentine Crescent, North Balgowlah

Judith Street, Seaforth

Parkes Rd, Artarmon

Ernest St, North Sydney

Port Hacking

Schools affected by planned stacks include:

Rozelle Public 

Wenona

Anzac Park

North Sydney Boys

Monte San Angelo Mercy

Cammeray

Seaforth

St Mary's

Port Hacking High