New Documents Regarding Chinese-Manufactured Drywall

In Future Environment Design's May Safety Suzy newsletter we sent out links to new documents produced by the Agency for Toxic Substances and Disease Registry (ATSDR) regarding Chinese-manufactured drywall.  One document was the 39 page "Health Consultation - Possible Health Implications From Exposure To Sulfur Gases Emitted From Chinese-Manufactured Drywall."  The second document was a 3 page fact sheet "Public Health Implications of Chinese-manufactured Drywall," which is a summation of the Health Consultation document.  The health consultation was established to estimate the exposures to sulfur compounds emitted from Chinese-manufactured drywall and the health risks associated with that exposure.

Chinese-manufactured drywall was imported into the United States (US) from 2006 to 2008, because of the increase demand caused by hurricane seasons of 2004 and 2005, and the already high national demand for new home construction.  In 2008, people living in homes built between 2001 and 2008 began reporting health issues. In addition, people reported the corrosion of certain metal components in their homes.  This became known as problem drywall, this issue wasn't only reported with Chinese-manufactured drywall or just in the south (see the map below for other areas with problem drywall).  The Consumer Product Safety Commission (CPSC)defines problem drywall as:

• Visual inspection observes blackening of copper electrical wiring and/or air conditioning evaporator coils and
• Drywall installed between 2001 and 2009

If both of the above are present look for corroborating evidence which may require outside lab testing.

Findings from the Health Consultation found that the drywall samples they tested emitted several sulfur compounds, including hydrogen sulfide, methy and ethyl mercaptans, carbonyl sulfide, dimethyl sulfide, and sulfur dioxide.  The levels found were a public health concern in 2009 when the testing was done.  Emission rates of these compounds increased with both temperature & humidity.

Exposures to sulfur compounds at the levels estimated from problem drywall in 2005 and 2006 may be associated with such effects as:

• Headaches
• Irritation of eyes, nose, & throat
• Feeling tired
• Problems controlling respiratory conditions (like asthma)

The odors associated with sulfur compounds could disrupt daily activities and cause stress.

If you have problem drywall the CPSC recommends remediation that would include the replacement of all:

• Possible problem drywall;
• Fire safety alarm devices (including smoke & carbon monoxide alarms);
• Electrical distribution components (including receptacles, switches, and circuit breakers, but not necessarily wiring); and
• Gas service piping and fire suppression sprinkler systems.

All testing and remediation work should be conducted in compliance with applicable building codes, occupational safety and health standards, and environmental regulations.

Related articles

• ATSDR report finds drywall imported from China in the 2000s may have affected human health
• Report backs Chinese drywall health complaints
• Report: Chinese drywall may have affected human health
• HUD and CPSC Issue Problem Drywall Guidelines
• Could multiple chemical exposures be the problem with Chinese Wallboard (Sheetrock)?
• The ongoing risk of Chinese drywall

Could multiple chemical exposures be the problem with Chinese Wallboard (Sheetrock)?

CNN, Wall Street Journal, Associated Press, and Indoor Environment Connections have all reported on the concern regarding imported Chinese Wallboard. It seems once the Chinese wallboard gets wet or damp it off-gases a rotten-egg stench made of sulfur-based gases. Homeowners claim these gases can corrode metals, and may cause headaches and aggravation of respiratory systems, such as asthma. Many of these reports quote health departments as saying that levels are not elevated enough to suggest an imminent or chronic health hazard. However, there should be a concern regarding the potential for multiple chemical exposures, their cumulative effect, and the potential for long exposures to low levels of the compounds on the occupants.

The Chinese wallboard problem may affect over 35,000 homes and so far, is in states with high humidity and temperature levels where homes were constructed or renovated between 2004 and 2008. These homes and buildings, because of the shortage of domestic wallboard (also called sheetrock, drywall, and gypsum board), were installing Chinese-imported wallboard (not all Chinese wallboard is a problem). Up until this point, the reports regarding the tests on the drywall, quoting one health department “has not identified data suggesting an imminent or chronic health hazard at this time.” Some reports actually say levels found in the affected homes are not elevated enough to be of concern. One report gave hydrogen sulfide levels of .05 to .07 parts per million (ppm). Another report detected “carbon disulfide levels of approximately 5 parts per billion – all samples were less than 15 parts per billion.” The same report also reported carbonyl sulfide in the same levels. Chamber testing of the Chinese wallboard emitted carbon disulfide, carbonyl sulfide, and hydrogen sulfide, while other tests of the wallboard found in addition sulfuric acid and sulfur dioxide. The Occupational Safety and Health Administration (OSHA), the National Institute of Occupational Safety and Health (NIOSH), or the Environmental Protection Agency (EPA) identifies all these compounds as toxic compounds. However, the levels found are below many of the standards used for worker exposure. This is the crux of the problem, the limitations of using worker exposure standards to evaluate indoor air quality have been known for a long time and a professional would use them with limitations, typically dividing them by a factor of 10 to 100. For example, the OSHA permissible exposure limit for carbon monoxide is 50 ppm, while the indoor air quality industry uses 5 ppm to 10 ppm as a guide for evaluating air quality in office buildings.

Exposure research is very limited when looking at exposures to multiple chemicals or to long term exposures to low levels of compounds. Since this research is so limited to the point of nonexistent it is hard to say what the impacts of multiple chemical exposures or long term low level exposures would be. The limited knowledge we have points to potential moderate or minimal effects on individuals based on the compounds they are exposed to. Exposure to the multiple sulfur gases for long periods or low levels could be causing the headaches; sore throats; repeated nose bleeds; breathing problems; respiratory infection; wheezing; sinus problems; and various other respiratory ailments that occupants have complained about. Our health departments should be erring on the side of health but too many times they side on convenience.