Gypsum Board

Photo Credit: La Miko from Pexels


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?


  1. When microscopic organisms combine mercury with carbon, they form the highly toxic methylmercury.3 High levels of methylmercury in the bloodstream of babies developing in the womb and young children may harm their developing nervous systems, affecting their ability to think and learn.3
  2. Mercury exposure at high levels can harm the brain, heart, kidneys, lungs, and immune system of people of all ages.3
  3. Mercury persists in the environment, accumulates in the food chain and in human bodies.2

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:

  • Made from natural gypsum1
  • Have the lowest amount of pre-consumer recycled content you can find5
  • Are Greenguard Gold Certified4
  • Have demonstrated lower embodied carbon or have CDPH emission certification4
  • Use lightweight boards when possible5
  • Prefer products with full disclosure of content through Health Product Declarations (HPDs)5

✓ When given a choice:

  • Choose clay or magnesium oxide boards which are healthier alternatives1

✗ Watch out for:

  • Paper-faced products with biocides advertised as having health or performance benefits4
  • Avoid using mold resistant drywall where not needed.5