ACA Upholds the Efficacy of Antimicrobial Paints Despite Press Release Issued by Northwestern University


Washington, D.C., May 20, 2019 — Northwestern University recently issued a press release based on the results of a study conducted by researchers at its McCormick School of Engineering (Hu, et al, 2019), titled “Impacts of Indoor Surface Finishes on Bacterial Viability.” Questions have been raised about the scientific statements made in the release, which asserted that “antimicrobial paints might do more harm than good.”

While the paper did note that “a non-pathogenic bacteria might form spores on a paint surface,” ACA finds the statement in the release to be a misrepresentation, since this is far from an indication of demonstrating potential harm.

The press release also states that “antimicrobial paints may prompt bacteria to develop more antibiotic resistance,” but a closer reading of the paper indicates that while the investigators specifically looked for antibiotic resistance they found no evidence. The paper states:

“In this particular case, the exposure to antimicrobial surfaces did not explicitly select for antimicrobial-resistant microbes…”

Further, the findings of the paper did not demonstrate increased resistance to either antibiotics or antimicrobials.

Finally, the press release stated that “bacillus is typically innocuous, but by attacking it, you might prompt it to develop more antibiotic resistance.” Again, such supposition is not supported by the paper, which clarifies that the observed evidence of “antibiotic resistance” in the study is simply related to the formation of spores, and no genetic determinants for antibiotic resistance associated were found in the (spore) genomes.

The subject of the underlying research study, namely the impacts of indoor surface finishes on bacterial viability in the indoor environment, is extremely important and has been the focus of considerable efforts on the part of product manufacturers, regulatory agencies and researchers around the world. Unfortunately, the press release highlighting the study does not clearly articulate the underlying findings of the research, creating potential for errant and inaccurate impressions.