Washington, DC — The rising toxicity of coal combustion wastes used in U.S. construction poses new public health and regulatory concerns, according to Public Employees for Environmental Responsibility (PEER). New evidence about toxic elements in re-used coal combustion wastes and the absence of government regulation open the door to consumer traumas such as occurred with Chinese wallboard, which afflicted thousands of homes in the Southeastern U.S.
One of the biggest components of the modern American home is gypsum, an average of more than 8 tons of which is spread over more than 6,144 square feet of wallboard. Gypsum used in wallboard now commonly comes from coal combustion waste as synthetic gypsum generated primarily by flue gas desulfurization. In 2001, only 15% of the total domestic gypsum supply was synthetic gypsum. By 2009, synthetic gypsum use had more than tripled, accounting for more than half (57%) of the national supply.
Contaminated Chinese drywall is synthetic gypsum and may have been used in more than 100,000 homes, producing complaints of foul odors, damage to electrical systems and illness. While the Consumer Product Safety Commission (CPSC) has not pinpointed the precise cause of the problem, it is now recommending that consumers rip out any Chinese drywall in their homes, regardless of cost. Chinese drywall is made from coal combustion wastes but in a less refined form than used by U.S. drywall makers.
At the same time, new anti-pollution requirements to reduce mercury emissions in coal-fired plants are dramatically elevating the mercury content of U.S. coal combustion wastes. Mercury is a neurotoxin and even low-level exposure over time has been associated with fatigue, memory loss and depression. U.S. Environmental Protection Agency studies are finding that mercury is released into the atmosphere during the manufacture of synthetic gypsum. In addition, EPA is finding mercury in the synthetic gypsum itself, both Chinese and domestic. In fact, the mercury levels in one major source of U.S. synthetic gypsum was the highest of six sources EPA tested – more than three times the highest Chinese sample (2.08 parts per million versus 0.562 ppm) – in 2009.
What happens to the mercury in the wallboard is less clear. The effects of heat and humidity on mercury release remain to be investigated. Also unknown is what happens at the product “end of life” – does mercury-infused wallboard require special disposal or demolition precautions? For example, currently old wallboard is land-filled or used as a “soil amendment,” where its elements can leach out over time.
“The question is whether you want mercury-laden wallboard in your child’s bedroom or school,” asked PEER Executive Director Jeff Ruch. “These questions about mercury in wallboard also need to be posed for other coal wastes that are being used in everything from ice removal to carpet backing to toothpaste.”
At present, the Obama administration is weighing a proposed regulation that would classify coal ash and other combustion wastes as hazardous, requiring special disposal to avoid direct human contact and prevent wastes from reaching water supplies. This initiative was spurred by a massive coal ash spill in December 2008 from TVA sludge ponds outside a Tennessee power plant. The current regulatory debate revolves around how to treat so-called “beneficial uses” of coal combustion waste, such as gypsum. “Coal combustion wastes are unquestionably hazardous and we trust that the Obama administration will finally make that classification official,” Ruch added, noting that the coal industry finances and controls most of the research about coal waste re-use. “We desperately need independent environmental and public health studies of the effects of injecting coal wastes into your home, workplace and throughout the stream of commerce.”