Mould has become a "national housing crisis" for people living in the dilapidated homes that characterize First Nations reserves across the country, according to a new study from researchers at the University of Victoria.

The research paper in the Journal of Environmental Health suggests that almost half of homes on reserves have enough mould to cause serious respiratory problems and other illnesses, and warns that the problem will only get worse if action isn't taken.

"The federal government must make a renewed and lasting commitment to improve the socioeconomic conditions on reserves that perpetuate mould growth in homes," the authors say in the report, published Wednesday.

The researchers, led by medical anthropologist Peter Stephenson, say that mould is thriving in the damp conditions on reserves caused by poor ventilation, structural damage and overcrowding.

Although they acknowledge that there isn't much scientific data on the problem, anecdotal evidence suggests it's a big one. Mould was found in 69 per cent of homes on the Ahousat First Nation reserve near Tofino, according to a newspaper article, while band council says that 21 per cent of homes on the Kitamaat reserve are affected.

Officials on the Snuneymuxw reserve in Nanaimo told CTV News this week that mould has become a big problem there as well.

"We're an urban First Nation and we're a nation amongst a city, amongst infrastructure ... [but] we still have inadequate housing, inadequate parks, inadequate water," band councillor William Yoachim said.

Toxins released by many types of mould can trigger allergic reactions, asthma, cold symptoms, concentration problems and weakened immune systems -- and can even cause death. When mould spores are inhaled, they can lead to a range of respiratory problems.

Children are the most vulnerable to the dangerous effects of mould.

Is home ownership the answer?

The UVic researchers suggest that a long history of removing aboriginal people from their traditional homes and placing them on reserves has degraded their economic power and left them dependent on Ottawa for survival.

"Failed commitments from the federal government to improve housing and socioeconomic conditions have resulted in a legacy of widespread substandard housing and severe housing shortages that yield overcrowding, which in turn aggravates mould growth," the study reads.

The authors also suggest that high unemployment on reserves means that few residents have the cash to maintain their homes.

But another problem may be what the researchers describe as the "paralyzing laws" that restrict home ownership on reserves and have led to just a small proportion of First Nations residents owning the houses their families have lived in for generations.

Manny Jules, chief commissioner of the First Nations Tax Commission, says that's the root cause of housing problems on reserves.

"You've got really a housing crisis right across the country, and to me that relates to the simple fact that First Nations members aren't allowed, like every other Canadian, the choice of owning their own home, and that leads to a situation where a lot of our housing is built substandard," he told CTV News.

Unlike in the rest of the country, the titles for the majority of reserve homes are vested in the Crown, and Jules says that needs to change.

"If you own your own home, you're going to take care of it better. You're going to make sure it outlasts you," he said.

Jules believes that home ownership would allow aboriginal people to build up equity, encouraging entrepreneurship that might help lift their communities out of poverty.

He says that housing issues are exacerbated by the fact that very few First Nations communities have adopted building codes, and inspection on building sites is rare.

"You're really building disposable homes," he said. The average home on a reserve only lasts for about seven years, he says.