A plan to move the occupants of FEMA trailers to apartments and hotels over concerns about formaldehyde fumes would lead to "a second great displacement" of New Orleans' residents, the city's mayor said. The relocation plan wouldn't work, Mayor Ray Nagin wrote in a letter released Tuesday and addressed to President Bush. "Because of the scope of damage to New Orleans' housing stock, much of which is still not recovered, there is insufficient housing here to place all New Orleans citizens needing to be relocated from trailers," Nagin wrote.

R. David Paulison, the administrator for the Federal Emergency Management Agency, said earlier this month that the agency hopes to get everyone out and into hotels, motels, apartments and other temporary housing by the summer, when the heat and stuffy air could worsen dangerous levels of formaldehyde fumes found in the trailers.

James McIntyre, a FEMA spokesman, said Tuesday the agency had not received an official copy of the letter. "However, we will work with the mayor's office to address his concerns in any way that we can within our priorities," he said.

The Centers for Disease Control and Prevention this month said that formaldehyde fumes from 519 trailers and mobile homes tested in Mississippi and Louisiana were, on average, about five times what people are exposed to in most modern homes.

Formaldehyde is a preservative commonly used in construction materials; it can lead to breathing problems and is also believed to cause cancer.

FEMA, which has provided trailers and rental assistance to hundreds of thousands of victims since the 2005 storms, has been offering lists of rental options to those living in trailers; months ago, the agency announced plans to close group sites in the state by June 1.

Nagin wrote that while he agrees the situation is urgent, moving families to apartments or hotels isn't an appropriate solution. The plan, he said, "will lead only to a second great displacement, as current trailer residents will be moved from New Orleans to apartments and hotels elsewhere in the Gulf Coast region."

Programs meant to bring back housing haven't gained traction yet, Nagin said.

There are 8,515 travel trailers in the city, most in front of storm-damaged houses, he said, citing FEMA figures. Another 2,366 house former residents outside of the city, he said, estimating that based on the city's average home occupancy rate, that 25,000 New Orleanians currently live in trailers and could be relocated.

Nagin said FEMA must do a better job of providing health information to those in trailers, telling the president he wants free checkups for current and former trailer residents; free treatment of any medical conditions "generated or exacerbated" by exposure to formaldehyde; and "guaranteed access to comprehensive, state-of-the-art medical care for any future formaldehyde-related medical conditions."

He said he also wants the government to make available "gap financing" to help homeowners living in trailers make outstanding repairs to their houses.

Written By BECKY BOHRER