Four companies -- Gulf Stream, Forest River, Keystone and Pilgrim International -- testified in a hearing before the House Committee on Oversight and Government Reform this week as part of a probe into allegations that the materials used to build the trailers that housed victims of Hurricane Katrina contained health hazards.

Background: Katrina Victims Struggle With Housing Amid Concerns Over Trailers

More Coverage on Katina's Aftermath:
Report: In New Orleans, Reinventing the Idea of Public Housing
Report: New Orleans Still Struggles With Hurricane Katrina Debris
Audio Slide Show: More on New Orleans' Illegal Landfills
Video: Watch Extended Interviews With Environmental Officials and Community Leaders in New Orleans on the Landfills Problem

Track the latest developments in the Gulf Coast region's long struggle to rebuild their cities and their citizens' lives in a series of broadcast and Web original reports.
-- National Public Radio

Beginning in January 2006, Jonathan Demme filmed in and around New Orleans, chronicling the lives of dozens of people who chose to return and try to rebuild after Hurricane Katrina hit.
-- KCET's Tavis Smiley

"Beyond Katrina: A Volunteer Story," follows the continuing volunteer efforts in the small town of Pearlington, Miss., where residents are still patching up damage from Hurricane Katrina.
-- Mississippi Public Broadcasting