Tests will be conducted to determine whether some hurricane victims living in government trailers are being sickened by formaldehyde emissions, FEMA said Friday.

The agency said it was responding to 46 complaints from people in Mississippi who claim they have had health problems since moving into the Federal Emergency Management Agency trailers after being displaced by Hurricane Katrina in 2005.

The move also comes three months after the Mississippi chapter of the Sierra Club issued a nonscientific report of its own testing which found high formaldehyde emissions in dozens of trailers in Mississippi and Louisiana. The environmental group has since tested trailers in Alabama and again found high levels, said Becky Gillette, co-chair of the organization.

FEMA spokesman Aaron Walker said agency director R. David Paulison wanted to do what was in the best interest of hurricane victims.

“They came to the decision … of victims first,” Walker said. “We want to make sure our residents feel comfortable.”

Walker said the agency couldn’t verify the Sierra Club findings “to make sure their testing was done adequately or correctly.” He said the Environmental Protection Agency will handle the sampling for FEMA.

Walker said FEMA has 113,000 trailers and that the housing program has been in effect since Hurricane Andrew in 1992.

“We are very confident in our trailer program. Currently, it is the fastest way that FEMA can provide short-term housing to disaster victims,” Walker said.

Formaldehyde is a widely used industrial chemical. The colorless, pungent gas can irritate eyes, nose and throat, and cause difficulty breathing and nausea at levels above .1 part per million in the air, officials say.

It is also known to cause cancer in the upper throat, the International Agency for Research on Cancer said.

Gillette said the Sierra Club has tested about 55 trailers in the three states, but not all of the trailers, which were made by several different manufacturers, had high formaldehyde levels. She said the testing was conducted with vapor monitors from Advanced Chemical Sensors, Inc., of Boca Raton, Fla.

Gillette said on average 8 out of every 10 people they encountered had health complaints.

“In a number of cases doctors have been requesting new trailers for their patients,” Gillette said. “When we started this we didn’t realize it would be quite so pervasive and widespread.”

Gail Scott, 49, of New Orleans, said since she moved into her FEMA trailer in May, she’s had a rash around her ears, eye and sinus irritation. She said her husband, Joseph, 49, has had similar problems. Scott said her grandson had lived with them, but “he said he couldn’t take it so he went to sleep on his mama’s floor.”

Scott said she contacted FEMA in June and three workers came out and told her to open her windows to “air out” the trailer during the day.

“But when you wake up in the morning, your eyes are burning because the trailer was closed up all night,” Scott said.

The EPA usually doesn’t regulate indoor air quality, but the Stafford Act makes allowances for emergency situations, said Jennifer Wood, EPA press secretary. She said EPA and FEMA were still developing the sampling plan.