After Hurricane Katrina, the Federal Emergency Management Agency (FEMA) provided 120,000 trailers to victims and relief workers. Residents soon began complaining of sore throats, burning eyes and noses and trouble breathing.

The cause? High levels of formaldehyde.

Formaldehyde is an industrial chemical that is bonded to nasal cancer, respiratory problems and even leukemia. Scientists believe that the fumes resulted from cheap wood and poor ventilation. Whatever the cause, the government banned the trailers from being used for long term housing. The fumes and health risks were too high.

But the trailers, which cost FEMA $130 million a year to maintain and store, recently found a new market. According to the New York Times, they are being bought by hundreds of contracting companies, dozens of which are in Louisiana, and by individuals in public auctions. Some buyers said they were unaware of the health risks.