Why stories about tainted drywall imported from China continue to raise a big stink

We’ve had months of reports about defective drywall that had been imported from China to help meet demand during the U.S. building boom. But it could be years before we understand the full extent of the problems the stuff might cause.

The core issue is that most of this drywall appears to be tainted in a way that causes it to off-gas sulfuric compounds that can corrode metal fixtures, including copper piping and wiring, and produce a “rotten egg” odor.

It has not been proven that the drywall emissions are causing health problems. Nor is it clear what’s causing the emissions – researchers, one Associated Press story noted, have suggested that sulfurous fumigants may have been sprayed on the exteriors of the panels and on the material inside them.

Problems with the drywall have been especially acute in the South, because high humidity accelerates the off-gassing. Many of the victims of drywall contamination are likely to be in storm-pummeled regions such as New Orleans and its nearby communities, which saw a lot of rebuilding after Hurricane Katrina.

It’s a mess, and the overall picture is still one of rising concern and uncertainty. The Florida Department of Health has received several hundred complaints about the drywall. (Click here for a PDF of a related briefing for the FDH by environmental consultant Environ Corporation.) Home Depot and Lowe’s have gone to considerable lengths to assure customers they have not sold any of the material.

And class action lawsuits have been launched against builders as well as manufacturers and suppliers, including Knauf Gips KG, Knauf Plasterboard Tianjin Company, and Taishan Gypsum Company, and L&W Supply Corporation and United States Gypsum Corporation, the AP story noted.

Encouraged by the recent disclosure that President Obama will bring up the drywall issue during his visit to China late this year, an editorial published this week by the Bradenton (Florida) Herald nonetheless called on the president “to engage the Chinese on this issue now.”

Indeed, the problem seems unlikely to diminish as the weeks go by, which is ratcheting up pressure on the major players – including China, which has faced its share of scrutiny over tainted exports – to respond.

“What we’re trying to do is get to the bottom of what is precisely going on,” Ken Haldin, a spokesman for Knauf Plasterboard Tianjin, told the AP.

One certainty: If the drywall’s defects eventually prove to be more extensive, or seriously dangerous, this already significant problem will become immense.

About 500 million pounds of drywall were imported from China between 2004 and 2008, and by some estimates, the material so far has been used in at least 34,000 homes and possibly as many as 100,000. The remedies for afflicted homeowners could get awfully expensive.