A federal scientist says his bosses ignored pleas to alert Gulf Coast hurricane victims about formaldehyde dangers in government-issued trailers and urged him not to go public with warnings.

Christopher De Rosa of the Centers for Disease Control and Prevention tells a House subcommittee his bosses told him such warnings could be misinterpreted if publicly released.

De Rosa is among the specialists testifying Tuesday before the House Science and Technology subcommittee on how the CDC and other agencies handled health complaints linked to the trailers that FEMA provided to victims of hurricanes Katrina and Rita.

Democrats accuse the Federal Emergency Management Agency of playing down the health hazards. In February the CDC announced that tests on hundreds of the FEMA trailers found formaldehyde levels averaged about five times above the levels in most modern homes.