Federal investigators reported Monday that a “strong association” exists between chemicals contained in Chinese drywall installed in thousands of homes at the height of the housing boom and electrical problems in those homes.

In addition, investigators said that the drywall is a possible cause of respiratory problems reported by home owners, brought on by hydrogen sulfide gas emitted from the imported drywall in combination with formaldehyde, which is common in new homes.

The finding, released by the Consumer Product Safety Commission, is the second in a series of progress reports on a widespread investigation into complaints by homeowners that their newly-built homes were giving off a rotten egg odor, causing respiratory problems and that their appliances and electrical systems were failing at abnormally fast rates.

More than 2100 homeowners, mainly in Florida, Louisiana and Virginia, have complained to the government of problems with their newly-built homes. Those three states experienced a home construction boom following devastating hurricanes.  With domestic sources of drywall running low a few years ago, many home builders turned to imported drywall from China, which investigators now say is linked to many of the homeowners’ problems.

The report found that Southern homeowners were particularly vulnerable. The problems brought on by the hydrogen sulfide and formaldehyde combination can be exacerbated by high humidity, high temperatures and poor air circulation brought on by highly air-conditioned homes.