MANATEE — Forget the strontium.
So says a federal task force, which said elevated levels of the metal no longer is a reliable indicator of corrosive drywall. The change was contained in revised guidelines that were issued Friday. Using strontium as a marker “may lead to false-positive results where a homeowner may mistakenly believe their home contains problem drywall,” the task force said.
Instead, a high level of elemental sulfur appears to be a better indicator and will remain in the guidelines for now, the task force said. The guidelines are used by health officials, scientists, consultants and homeowners to identify bad drywall.
More than 3,500 U.S. homeowners, most from Florida and Louisiana, have complained to the U.S. Product Safety Commission about drywall that emits noxious odors and corrodes electrical wires and air-conditioning coils. The complaints focus on drywall imported from China during the homebuilding boom and post-hurricane reconstruction.
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In its initial guidelines, released in January, the task force said drywall with strontium levels in excess of 1,200 parts per billion likely was corrosive. Strontium is a soft metal often used in fireworks and flares.
But further testing revealed that wasn’t always the case, the task force said.
An attorney representing homeowners with problem drywall and a Florida drywall researcher said Tuesday they had similar findings.
Steve Mullins, an Ocean Springs, Miss., attorney, said tests conducted for his clients have found low strontium levels in corrosive Chinese drywall and high levels in non-corrosive U.S. drywall.
“(Strontium) is not accurate,” he said. “I tried to tell them a year ago, but, hey, it’s the federal government.”
Gary Rosen, a Davie environmental/construction consultant who is investigating the drywall, has previously criticized the strontium standard as based on “Mickey Mouse science.” He said he agrees with the guideline revision.
The change comes as ASTM International considers adopting a standard for testing strontium in drywall by using a type of X-ray device. A committee is scheduled to discuss the proposed standard in November, ASTM spokeswoman Barbara Schindler said.
Duane Marsteller, transportation/growth and development reporter, can be reached at 745-7080, ext. 2630.