Research Can't Yet Explain Link of Chinese Drywall to Home, Health Woes

Federal investigators have been unable to prove a definite link between imported Chinese drywall and home damage and health issues. But they aren't done investigating.

The Consumer Product Safety Commission said that the problems with the Chinese manufactured home product require further study. It plans to release more information next month.

This week, the federal agency released preliminary results of three studies. The researchers said they could not definitively explain the cause of certain health problems or corrosion of pipes and wire damage that many homeowners, especially in the Southeast, have been blaming on the drywall.

"While the studies have discovered certain differences between Chinese and non-Chinese drywall, further studies must be completed to determine the nexus between the drywall and the reported health and corrosion issues. The conclusions of each study are preliminary and may be subject to change with the results of later studies," the CPSC report said.

To date, CPSC itself has received nearly 1,900 reports from 30 states, the District of Columbia and Puerto Rico about problem drywall in homes.

Complaints from homeowners, many of whom have had to abandon their places, are that the fumes from the drywall are corroding, or blackening, indoor metals, such as electrical components and central air conditioning system evaporator coils, as well producing various health symptoms, including persistent cough, bloody and runny noses, headaches, difficulty in breathing and irritated and itchy eyes and skin.

The government studies thus far have found that Chinese drywall contains higher concentrations of strontium and elemental sulfur than non-Chinese drywall and that it emits "volatile sulfur gases" at a higher rate than non-Chinese drywall.

Indoor air studies conducted on 10 homes did not detect any or found only very limited indications of certain sulfur compounds. Some concentrations of two irritants, acetaldehyde and formaldehyde, which could exacerbate conditions such as asthma in sensitive populations, were detected in homes with and without Chinese drywall.

Various state agencies along with the CPSC, the Centers for Disease Control and the Environmental Protection Agency acknowledge the problems and health symptoms have been working in the issue.

A 50-home indoor air study scheduled for release next month will provide a more comprehensive picture, according to the CPSC. It also plans to release a preliminary engineering analysis of electrical and fire safety associated with corrosion. A study of long-term corrosion issues will not be completed until June of 2010.

U.S. officials said that the Chinese government is assisting with the drywall investigations.

There have been some reports of homeowners losing their insurance because of potential issues associated with the drywall. Homeowners policies do not cover damage from defective products but some underwriters fear the damage could eventually lead to a fire, water leak or other claim that might be covered.

In one case, Florida's state-backed property insurer initially rejected a renewal on a policy on a home with Chinese drywall but reconsidered after it said it found the damage was not as bad as first thought and would not likely to result in a covered claim.

An Associated Press analysis found that more than 500 million pounds of Chinese gypsum board was imported between 2004 and 2008 - enough to have built tens of thousands of homes.