Will it kill me if I walk past it? What should I do if I've been exposed? All your questions answere

Australians heading to work, school and even their local hospitals are now having to walk past sites that are contaminated with asbestos.

Concerns have risen about people falling ill from asbestos-riddled mulch, which has now been detected at more than 50 sites across NSW.

More than 5 million people live in Sydney with asbestos detected in topsoil at schools, hospitals and parks stretching from the CBD to Emu Plains at the foot of the Blue Mountains, and from Parramatta to Campbelltown.

The material was first discovered on January 10 at the new Rozelle Parklands playground in Sydney's inner west.

Trees and garden beds around the city have since been taped off with 'possible asbestos' notices attached.

A construction site at The Children's Hospital at Westmead, Bicentennial Park, in Glebe, and Oran Park Fire Station are the latest sites to return positive results.

Daily Mail Australia has compiled a list of all the questions that you may have on your mind to help you navigate through the widespread asbestos scare.

Concerns have risen about people falling ill from asbestos-riddled mulch, which has now been detected at more than 50 sites across NSW (pictured, taped off areas on a Sydney footpath)

Should residents be concerned?

Professor Sonja Klebe, from Flinders University's College of Medicine and Public Health, said while it was likely most Australians have some level of asbestos in their lungs already due to old houses and buildings, the risk of getting sick was very low.

Homes and buildings built before the 90s are likely to be riddled with asbestos, while one in three Australian homes are still found to contain the substance today, according to the government's Asbestos and Silica Safety and Eradication Agency.

'We all have a level of background exposure. What happens is if you get anything above that then that increases your risk,' Ms Klebe told Daily Mail Australia.

'If asbestos isn't disturbed, the risk is very low.'

What should residents do if they've been exposed?

Ms Klebe urged anyone who had walked past possible asbestos sites in NSW recently 'not to panic' as it was unlikely anyone could get sick from that level of exposure.

Instead, people should log any potential contact to the National Asbestos Exposure Register, which allows them to trace back any related illness.

The first symptoms from asbestos exposure don't show up for 30 years, Ms Klebe added.

Ms Klebe urged anyone who had walked past possible asbestos sites in NSW recently 'not to panic' as it was unlikely anyone could get sick from that level of exposure (pictured, Victoria Park)

'That's one of the reasons why it's been so hard to track what people are exposed to,' she said.

The professor also noted there was some risk with children who may be unknowingly playing in contaminated mulch.

'The risk of getting sick is proportional to the type of fibre and we don't know which type that is,' she said.

'Exposure earlier on in life is thought to be more significant given it's on average 30 years before any symptoms show.'

The total number of sites that have tested positive around the state has climbed to 54 as of Thursday, according to the latest data from the NSW Environmental Protection Agency (EPA).

What are the symptoms?

Those who have been exposed to dangerous levels of asbestos may start to show signs of breathlessness and chest pain.

An x-ray will then show a build up of fluid on the lung.

Those who suffer lung cancer related to asbestos exposure have on average a year to live.

Almost a dozen trees on Abercrombie Street in Chippendale (pictured) were taped off on Wednesday over fears asbestos could be contained in the mulch underneath

What have authorities said?

NSW Premier Chris Minns said the crisis is a 'big problem' and emphasised the serious nature of the incident.

'The EPA is investigating it, it's a serious offence and fines are up to $2million,' he told reporters on Thursday.

However he assured the community that the contamination while concerning is not a major health concern due to the bonded nature of the fibres, which make them less likely to become airborne.

'This is bonded asbestos, it's not safe and we don't want it in our community but the risk is not as serious as if you had asbestos fibre in your backyard.'

Will asbestos be a long-term problem in Australia?

Ms Klebe said it wasn't at all unusual for an outbreak of this sort to happen in current times.

'It's not going to go away,' she said.

'This is a problem we're going to have in the future.'

Professor Sonja Klebe, from Flinders University's College of Medicine and Public Health said asbestos would be a problem well into the future for Australia

Ms Klebe said authorities should be measuring the air to test the levels of asbestos.

'You wouldn't want it in a playground but if it's just on the ground and it's not disturbed, it's probably going to have little affect,' she said.

'The chances of getting sick are extremely small, you don't want people to panic but we're going to have a big problem for a long time.'

Almost 800 locations across NSW have now been tested for the deadly substance.

The NSW EPA says the investigation is ongoing and it is yet to determine the source of the affected mulch.

GreenLife Resource Recovery Facility, where some of the mulch is understood to have originated from, denies it is to blame for the asbestos issue.

The company's Bringelly site, in Sydney's south-west, had four clean-up notices issued by the EPA after multiple asbestos pollution incidents prior to it owning the site.

Greenlife general manager Domenic Vitocco insists his company is not to blame, telling Daily Mail Australia last week it has 'been made a scapegoat' by the state government.

'All the testing from the EPA has come back from our yard clean. Our testing has come back clear and we're a little bit puzzled as to how this is all happening,' he said.

'During the investigation, I can't really talk too much, but what I do know is that a number of these sites are major remediation sites... but I can't comment further.'