Most Portable Air Cleaners Have Not Been Tested for Effectiveness and Safety

Strategic Insights -

Portable air cleaners aim to prevent the indoor spread of infections by removing viruses and other disease-causing pathogens from the air. However, a new review of nearly 700 studies found that most of these devices have not been tested for their effectiveness in people. Furthermore, very few studies evaluate their potential harmful effects, including the generation of chemicals such as ozone, formaldehyde, and hydroxyl radicals to kill microbes.

Key Takeaways:

  • Only about 8% of the studies tested the effectiveness of air cleaning devices on people, while over 90% tested the devices in unoccupied spaces.
  • 44 studies examined an air cleaning process called photocatalytic oxidation, but only one tested whether the technology prevented infections in people.
  • 35 studies evaluated plasma-based technologies for killing microbes, but none involved human participants.
  • 43 studies on filters incorporating nanomaterials designed to capture and kill microbes also lacked human testing.
  • Only 14 out of 112 studies assessing pathogen-killing technologies tested for harmful byproducts.
  • The safety of these products is a major concern, as some generate chemicals that can potentially harm people if inhaled.
  • The gap between marketing claims and evidence of effectiveness from studies on people is a significant issue, with most devices not having been properly tested for efficacy.
  • The review highlights the need for more research to identify the safest and most effective options for improving air quality in homes, schools, and healthcare facilities.

Statistics:

  • 672 studies were analyzed in the review, covering technologies such as HEPA filters, ultraviolet light, and special ventilation designs.
  • 44% of the studies examined photocatalytic oxidation, while 31% evaluated plasma-based technologies.
  • 62% of the studies on filters incorporating nanomaterials did not include human testing.
  • Only 13% of the studies on Pathogen-killing technologies were tested for harmful byproducts.
  • The analysis covered studies published from the 1920s through 2023.

Sources:

  • Baduashvili, A., & Bero, L. (2023). Engineering Infection Controls to Improve Indoor Air Quality. Annals of Internal Medicine.
  • The Conversation -- USA (3). Most air cleaning devices have not been tested on people and little is known about their potential harms, new study finds.