After being placed in FEMA trailers (over 40,000 of which are still in use), many residents complained of illness, breathing difficulty, rashes, and death (well, THEY didn't complain of death, but some folks took it upon themselves to do it for them). In May of 2006, FEMA asked folks over at the Agency for Toxic Substances and Disease Registry, or ATSDR (don't worry, I've never heard of it either), to write up a "health consultation" on the FEMA trailers. The chief of toxicology for ATSDR, Dr. Christopher De Rosa, replied that any report would have to include long-term risks of exposure to formaldehyde. Taking that little tidbit under advisement, FEMA then went UNDER Dr. De Rosa to a couple of his staffers and had THEM write up the report sans any references to formaldehyde causing all manner of long-term health problems (cancer being one of the biggies).
Formaldehyde is a nearly colorless, smelly gas that is used in many manufacturing procedures-- including as an adhesive in plywood used in, you guessed it, trailers!
Many lawmakers are very upset over what appears to be FEMA's pressuring of scientists to give them results they wanted rather than information that John Q. Trailer really would have liked to know and the chairmen of several House subcommittees have written letters ripping FEMA, ATSDR, and the DHS a collective new one over the scheme to hide from the public that they were being put in trailers filled with cancer gas.