The corruption scandal engulfing world football's governing body FIFA has cast a renewed spotlight on the conditions endured by hundreds of thousands of workers labouring on infrastructure for the 2022 World Cup in Qatar.

Qatar — the world's richest country per capita — is spending $260 billion building the stadiums, public transport systems, freeways, hotels and apartments to stage the tournament.

Yet foreign workers, mostly from South Asia, are being paid as little as $50 a week as the labour to build the infrastructure.

Forced to live in squalid and unsanitary conditions, they work under a controversial system called kafala, which requires them to surrender their passports to their employers.

Former ACTU president Sharan Burrow, now head of the International Trade Union Confederation (ITUC), said the kafala system was tantamount to slavery.

And FIFA critics, including three Australian campaigners, said the scandal-plagued governing body FIFA needed to reassess where the next two World Cups should be held.

Ms Burrow, Mustafa Qadri — a London-based researcher for Amnesty International — and Jaimie Fuller — the Swiss-based Australian businessman behind the Skins sportswear brand — have all visited Qatar to investigate the working and living conditions of labourers employed on World Cup projects.

Filthy underbelly behind the glitz and glamour

Ms Burrow was Foreign Correspondent's guide on an exclusive tour of the grim underbelly of the glitzy Qatar capital Doha.

Arriving at a workers' hostel, Ms Burrow said: "You can see that on the outside this looks almost human. And then you walk in here and you see there are about 300 men here in about 20 rooms."

It was mid-evening. The courtyard of the small multi-storeyed building was festooned with washing. The men, all Nepalese, had just finished their meals at the end of another long, sweaty day.

Those meals had been cooked on filthy gas burners in a room where the floor was caked in grime and the walls consisted of breeze blocks and crumbling plaster.

"This is the cooking area, and you can imagine 40 or 50 men in here trying to prepare meals in what are totally unsafe conditions. And it's filthy, just filthy. The squalor is unbelievable," Ms Burrow said.

The labourers told Ms Burrow they had to work six days a week, eight hours a day, most often with two to four extra hours of obligatory overtime.

Most men said they were paid about 600 Qatari riyals ($215) a month plus about 200 riyals for food.

"Six hundred riyals is very, very low, even with food on top of it," Ms Burrows said, adding that the ITUC had asked the Qatar government to set a basic minimum wage.

Anxious about staying too long in the workers' hostel — and risking arrest for an unauthorised visit — Ms Burrow left the men with a promise: "We'll keep coming back to Qatar until they change the laws. Until you have proper rights, you get a fair salary and you can live with dignity."

Outside Doha 'it feels like you're in the third world'

On several other days, Foreign Correspondent went with Mr Qadri to the industrial areas on the capital's outskirts.

Many roads were unsealed and choked with heavy trucks and construction equipment.

Hundreds of men milled around a mosque and a small shopping area with no recreational facilities.

Younger workers from South Asia played cricket on a rubble-strewn wasteland.

Mr Qadri, like Ms Burrow, stuck to the back streets, concerned about police seeing him talking to workers; he had been detained for six hours on a previous evening.

"Compare it to Doha, which is this amazing big city, and here it feels like you're in the third world," he said.

"In one of the richest countries in the world there's no proper sewerage system here, or electricity, and often there are issues with very basic accommodation.

"What really strikes me is that these are the workers building stadiums, building hospitals that in the years ahead will be the showcase for developing this country, yet this is the way they're living."

Mr Qadri spends as much time as possible interviewing workers.

"What they're saying mostly is that they're not paid on time and they're not paid enough," he said.

"And if they're not paid on time and if they complain, there's a risk of their employer going to the authorities saying, 'this worker has absconded'.

"They don't have their ID and they can get kicked out of the country or stuck in detention for a long time."

Urgent reform needed to prevent deaths

While Ms Burrow said she would like Qatar to be stripped of the World Cup, Mr Qadri felt the tournament provided unique leverage.

"We say that the World Cup is an opportunity for Qatar to really demonstrate that it is genuinely trying to improve conditions for labour," he said.

The Supreme Committee for the Delivery and Legacy (SCDL) of Qatar 2022, chaired by Qatar's emir, certainly understands worker safety is a key issue internationally.

It claims there has not been a single fatality at any of the five stadiums being renovated or built in the country.

Foreign Correspondent was allowed to film the site works for the Al-Wakrah stadium, but no-one representing SCDL was allowed to speak on camera, or even for direct attribution, about safety, workers' rights or anything else.

Ms Burrow said statistics compiled by the Indian and Nepalese governments showed more than 200 citizens from each of their countries had died each year working in Qatar.

There are fears many more will die unless there is urgent reform.

Nepalese workers 'refused permission to go home for funerals'

Mr Fuller has been campaigning for a corporate boycott of FIFA and urged the establishment of a new organisation focused on the transparency of executive decisions and financial accounts.

Having visited Qatar and arranged for himself to be smuggled into labour camps to video conditions, Mr Fuller said he was determined to draw attention to the plight of workers.

"We've seen only in the past few weeks with the Nepalese earthquake, a huge number of Nepalis have been prevented from returning home for family members' funerals because the Qatari authorities and their employers have refused to give them permission," he said.

Speaking to Foreign Correspondent from Zurich after Sepp Blatter was re-elected president of FIFA, Mr Fuller said the organisation had a corruption issue.

"We're dealing with an organisation that really has a culture of corruption over generations, and you don't change culture by keeping the same leadership," he said.

However, Mr Fuller invested some hope in the criminal investigations underway.

"We know there are continued investigations between the US feds through the FBI and the Swiss federal prosecutors as well," he said.

"I think it's pretty self-evident that they are looking to go up the tree, so I wouldn't be too sure that Sepp Blatter will be there in four years' time."

Realistically, Mr Fuller did not expect any change in the World Cup calendar.

"It's highly unlikely that Russia [the 2018 hosts] or Qatar could be stripped of the World Cups," he said.

"I think there's a significant legal question there because certainly the amount of money that's been spent already and committed and invested in those countries is enormous."

Editor's note (July 15, 2015): The headline on this story has been changed to clarify that the report refers to World Cup infrastructure as well as stadiums.