Because mining raw gypsum can be an energy-intensive process, pre-consumer recycled gypsum (aka flue gas desulfurization (FGD) or synthetic gypsum) is often considered more sustainable.1 FGD gypsum uses sulfur dioxide waste created from coal burning. Pollutants such as mercury can be captured with the sulfur dioxide. When FGD gypsum is heated during the manufacturing process, mercury is released from the smokestacks and into surrounding communities, posing serious health concerns.2
Drywall manufacturing plants in the USA released over 3 tons of mercury into the air between 2009 and 2018. These figures continue to climb every year as more and more FGD is used.2
While both FGD and natural gypsum contain and can release mercury during manufacturing, the highest levels by far come from facilities producing drywall with high percentages of FGD gypsum.2
Why is mercury pollution from drywall factories a concern?
An additional concern is that both natural and synthetic drywall may also contain biocides and toxic additives used for mold resistance and other performance requirements.1
FGD content / pre-consumer content of synthetic gypsum varies greatly based on manufacturing plant! Be sure to use the following spec language to limit FGD content:
“Drywall product to contain lowest amount of FGD gypsum (pre-consumer recycled content) available. Manufacturer to disclose how they monitor and limit mercury content and emissions.”
✓ Look for products:
✓ When given a choice:
✗ Watch out for:
Visit these sources for more information.