( Reuter )- Many of the government-supplied trailers housing thousands of people displaced by Hurricane Katrina contain potentially dangerous levels of the chemical formaldehyde, U.S. federal health officials said on Thursday.
"In some of these situations, the formaldehyde levels are high enough where there could be a health hazard to the people who are living there," U.S. Centers for Disease Control and Prevention Director Dr. Julie Gerberding said.
Gerberding told reporters in New Orleans, which was devastated by the 2005 storm, and by telephone link that the CDC is urging the U.S. Federal Emergency Management Agency to get people out of the trailers "as quickly as possible and certainly before the warm summer months arrive."
Gerberding noted that the formaldehyde levels were found in the cooler months of December and January and that warmer temperatures tend to drive them higher.
FEMA Administrator David Paulison said about 38,000 families remain in FEMA trailers and mobile homes, or about 114,000 people. He said more than 15,000 families had moved out since November, with 800 to 1,000 families moving out weekly.
Paulison said FEMA, whose response to the disaster has been criticized as slow and ineffective, will aim to "get as many people out as we can" by summer into different housing.
Tens of thousands of people lost homes in Katrina in 2005 and many have been living for about two years in trailers bought by the government for temporary housing. Some residents have attributed health problems to formaldehyde exposure.
The CDC conducted indoor air-quality tests for formaldehyde between December 21 and January 23, 2008 on a random sample of 519 travel trailers and mobile homes in Mississippi and Louisiana.
Formaldehyde is a chemical used widely in the manufacture of building materials. It also is used in embalming fluid. It can irritate the skin, eyes, nose and throat, and high levels of exposure may cause some types of cancers.
The CDC said average levels of formaldehyde in all the tested units was about 77 parts per billion (ppb). Long-term exposure to levels in this range is linked to elevated risk of cancer and as levels rise above this range, there can also be a risk of respiratory illness, the CDC said.
The CDC said indoor air levels of formaldehyde commonly are far lower -- in the range of 10 to 20 ppb. Levels seen in the various units ranged from 3 ppb to 590 ppb, the CDC said.
Gerberding said the CDC analysis did not answer whether the formaldehyde levels seen in the trailers actually caused the illnesses reported by some of the trailer residents.
"Hindsight is 20-20. We can look back and say, 'Yeah, maybe we should have did something differently.' With the information we had, we thought we moved very quickly," Paulison said.
Paulison said FEMA will never again use travel trailers, which he called too small and made only for short-term use, to house people displaced by future disasters but may use mobile homes, which he said are built for longer term occupation.
"We are not housing experts. That's obvious. We should not be in the housing business," Paulison said. "We didn't order travel trailers with extra formaldehyde. We bought the same ones we've been buying for 20 years."