This article has been updated to include statements from the American Chemistry Council (ACC) and Perkins+Will white paper co-author Suzanne Drake.
Statement from Komal K. Jain ACC Biocides Panel executive director:
Antimicrobials are extremely well-regulated, critical ingredients used in building products. While this report primarily discusses the use of antimicrobials to protect public health and safety, most antimicrobials used in building materials act as key material preservatives. This report fails to clearly distinguish between these uses or explain the need for and benefits of antimicrobials as material preservatives, creating the misleading impression that antimicrobials are not beneficial additions to building materials. For example, they ensure low-VOC paint doesn’t require refrigeration, and they extend the life of materials such as wood and drywall. By reducing additional refrigeration and transportation steps and the need for frequent replacements, antimicrobials are key elements to creating more sustainable construction projects.
Overall, the report is based on overly generalized claims and a limited examination of the extensive body of literature supporting the safe use of antimicrobials. In particular, there is no evidence that the use of antimicrobials in building materials contributes to the risk of ‘super-bugs.’ The paper relies on cherry-picked statements by the U.S. Food and Drug Administration and Centers for Disease Control and Prevention on a narrow set of antimicrobials in particular uses, which are far from representative of antimicrobials used in building materials. Antimicrobials are tightly regulated by the federal government, undergoing robust evaluation by the U.S. Environmental Protection Agency and often the FDA before they can be used.
As organizations that pride themselves on promoting sustainable and healthy building materials, it is important that Perkins+Will and the Healthy Building Network offer accurate information about products, such as antimicrobials, that help increase sustainability and have a long history of careful and safe use in building materials.
White Paper Co-Author Suzanne Drake:
As noted in the paper, we are adding products marketed as antimicrobial to the Precautionary List, including both products making health claims and those attempting to 'up-sell' a preservative. Alternatively, we understand that antimicrobials acting as a preservatives are necessary and widespread, due to limited viable alternatives, therefore these substances are not currently included on the Precautionary List but on our Watch List. (See pages 10, 26, and 27 of the paper).
As specifiers focused on creating healthy environments, our main focus is to raise awareness of the unintended consequences of antimicrobial use, which is what led us to the conclusion that we should try to avoid them where possible.
All the studies and source information that informs the paper, and our conclusions, are listed in the endnotes and appendix; we invite all readers to explore these sources in more detail to form their own opinions.
Is it possible that antimicrobial ingredients used to kill bacteria on countertops, floor tiles, and other building materials are doing more harm than good? A recent white paper by global architecture firm Perkins+Will with the Healthy Building Network suggests so. While such treatments are intended to destroy microorganisms, this white paper argues that their widespread use is likely a cause of "super bugs caused by microbial resistance, contamination of aquatic ecosystems, and potential exposure to known or suspected carcinogens like formaldehyde," according to a recent Perkins+Will press release.
Potentially toxic ingredients such as boric acid, propiconazole, formaldehyde, and silver nanoparticles that can be found in wood products, hardware, adhesives, paints, textiles, and caulks are often used as coatings or preservatives for products during fabrication or after installation. In response to their findings, Perkins+Will has added antimicrobial products marketed as healthy or beneficial to human health to its precautionary list of materials that the firm avoids.
“What consumers don’t realize is that the federal government considers antimicrobial pesticides because they are agents used to kill or control living organisms—and they should therefore be used with great care,” said Suzanne Drake, senior interior designer at Perkins+Will and co-author of the white paper, in the press release. “Because we caution against using building products containing ingredients suspected of hazardous health impacts, we should avoid products containing antimicrobial ingredients. That includes building products intended for healthcare settings.”
If you don't have time to read the full 42-page document, Perkins+Will offers 10 takeaways:
This story has been updated since it was originally published. Perkins+Will have added antimicrobial products marketed as healthy or beneficial to human health to its precautionary list.