U.S. Links Problem Drywall, Health Woes
Americans exposed to emissions from drywall made in China "may have experienced adverse health effects or a reduced quality of life," the U.S. Centers for Disease Control and Prevention has concluded in a long-awaited study.
Those are short-term effects, however, and the study was not conclusive as to adverse longterm effects. Researchers also cautioned that only a small sample was tested and that the results could not be generalized to all Chinese-made drywall.
Finally, they said that the data could not be used to determine if people are still being exposed to drywall emissions at levels that could affect health.
Thus laced in caveats, the long-awaited report may not satisfy the many U.S. critics of problem drywall from China—a concern that has mushroomed into an industry all its own.
“Health Consultation: Possible Health Implications from Exposure to Sulfur Gases Emitted from Chinese-Manufactured Drywall,” by CDC's Agency for Toxic Substances & Disease Registry (ATSDR), was released Friday (May 2).
The report evaluated samples of drywall imported from China in 2005, 2006 and 2009. For comparison, the researchers also looked at drywall manufactured in North America in 2009.
The U.S. Consumer Product Safety Commission (CPSC) launched its investigation into problem drywall in 2009, following more than 4,000 complaints from U.S. homeowners about sulfur odors; rashes, headaches and other health problems; and corrosion and blackening of fixtures, air conditioner coils, plumbing and other metal components in the home.
Thousands of U.S. homeowners complained about metal corrosion and sulfur odors in their homes.
In 2011, the Safety Commission issued guidance on how to tell if a home had problem drywall. The commission also noted that "not all drywall from China is problem drywall" but decided with the CDC's agency that more study was needed on emissions levels and health effects.
In 2012, the U.S. Department of Housing and Urban Development estimated that problem drywall from China had most likely been used in about 11,000 new homes.
Analysis of the drywall in the new study was conducted by Lawrenece Berkeley National Laboratory. The lab evaluated 30 drywall samples provided by CPSC for emissions of several sulfur compounds, including hydrogen sulfide, methyl and ethyl mercaptans, dimethyl sulfide and sulfur dioxide.
The lab measured the compound emissions on all samples in 2009; in 2010, it measured emissions from four Chinese-made samples and one North American-made sample.
|ATSDR / CDC|
Working with Lawrence Berkeley National Laboratory and Georgia Tech, the CDC agency analyzed 30 drywall samples in 2009 and a smaller group in 2010. Indoor air concentrations of drywall emissions declined in 2010, suggesting that concentrations were highest at initial installation in 2005-06.
The Georgia Institute of Technology (Georgia Tech) then developed a model for estimating indoor air concentrations of a room made with the drywall. Lawrence Berkeley Lab used those models to determine health exposure and risks for each sample.
The researchers found that people exposed to the sulfur compounds emitted by some of the Chinese drywall "may have experienced health effects."
The estimated concentrations "were a public health concern at the time of testing (2009 and 2010)," a study Fact Sheet reports. "These levels are consistent with metal corrosion observed in homes with problem drywall."
The emission rates "increased with both temperature and humidity" but decreased between the 2009 and 2010 tests, suggesting that emissions were probably higher when the drywall was manufactured in 2005 and 2006, the team said.
"Exposures may have been higher when the drywall was newly manufactured and installed."
|ATSDR / CDC|
Humidity and higher temperatures exacerbated drywall emissions levels, CDC found. Most of the problem drywall complaints have come from homeowners in the U.S. South and West.
Health effects related to sulfur compound exposure include headaches; irritation of eyes, nose and throat; fatigue; and problems controlling asthma and other respiratory conditions, the report said.
No health concerns were found with the North American samples.
The CDC's report offers these recommendations.