AAP staff report
A recent report indicates that since 2009 Chinese drywall manufacturers have effectively reduced the sulfur emitting emissions – but indicates that sheet rock imported from China between 2001 and 2008 have measurable differences in emissions that are being studied for causing health and metal corrosion problems in homes.
“CPSC Staff Preliminary Evaluation of Drywall Chamber Test Results Reactive Sulfur Gases”, a draft report released in March 2010, was conducted by the Lawrence Berkeley National Laboratory to evaluate emissions of specific sulfur gases from drywall products produced in North America and China.
The report was contracted after the U.S. Consumer Product Safety Commission registered more than 3,000 consumer complaints on health effects and corrosion of metal components in both newly built homes and homes renovated during the years 2001 through 2008.
The study looked at possible exposures of sulfur-containing compounds in homes that contain drywall produced in this period. Consumer complaints related to health effects from residents on everything from recurring headaches, skin and eye irritation, and respiratory ailments from difficulty in breathing, to persistent coughs and sinus problems, nosebleeds and asthma attacks.
The results of the LBNL chamber studies demonstrated considerably higher emission rates from Chinese drywall samples manufactured in 2005-2006 compared to samples from North America.
The report authors, Michael Babich, Ph.D., Mary Ann Danello, Ph.D., Kristina Hatlelid, Ph.D., M.P.H., Joanna Matheson, Ph.D., Lori Saltzman, M.S., and Treye Thomas, Ph.D., state that the technical report is also awaiting results of interrelated investigations.
The preliminary evaluation of chemical emissions from drywall has identified possible source differences between products and possible sources of chemical exposures in homes. Data from the study contained measurable reactive sulfur compounds of hydrogen sulfide, sulfur dioxide, carbon disulfide, methyl mercaptan, dimethyl sulfide, and carbonyl sulfide.
The top ten of thirty reactive sulfur emitting drywall samples in the study are from China. The report states that patterns of reactive sulfur compounds emitted from drywall samples show a clear distinction between the Chinese drywall samples manufactured in 2005/2006 and North American drywall samples, with the exception of two Chinese samples which have similarities to the North American emission profile.
The report noted that newer Chinese samples with a manufactures date of 2009 or later do demonstrate a marked decrease in sulfur emissions as compared to the 2005/2006 samples, and in some cases are similar to those of the North American samples.
A website (www.chinesedrywall.com) is dedicated to educating the public about Chinese drywall problems. It contains the latest studies and other reports, along with legal and legislative updates on related cases.
The reports and news catalogue damages to air conditioners, electrical wiring, copper plumbing, appliances to electronics. The health problems, according to the site, come from the tendency for drywall produced in China during that period to be “friable”, or allowing small particles to dislodge easily and become airborne risks as toxic particle that can enter lungs.
The magnitude of the problem is difficult to measure, as the comparatively affordable imported drywall was used during one of the biggest housing booms in recent history – along with remodeling of older homes. The Chinese drywall was not always identifiable later on as it was sometimes manufactured in China for American companies.
Consumers are encouraged to call a home inspector if their home was manufactured or remodeled to include new drywall between 2001 and 2009 – when there are signs of a distinct odor that has been described as everything from rotten eggs to ammonia and even a sweet smell.
Other signs of are corrosion of air conditioner coils and wiring – with a possible dark, sooty residue. Flickering lights, or getting shocks from light switches and sockets are other signs of corrosive wiring problems – as is having to re-set circuit breakers frequently when they are not being overloaded.