The product claims sounded great:
“Formulated with all natural ingredients.”
“Shown to neutralize viruses and bacteria in a laboratory environment.”
“So safe its’ ingredients are US EPA Exempt from registration under the minimal risk pesticide FIFRA section 25(b).”
“Antimicrobial multi-surface cleaning solution for fighting and killing germs, bacteria, and viruses that can be spread throughout the air or on surfaces.” 
Perhaps best of all was the assurance that after application, the product would continue to kill microbes, including the SARS-CoV-2 virus, for 72 hours. The exact formula was withheld as “Propriety / Trade Secret Claimed” on both the Safety Data Sheet and the product literature, but the product website provided efficacy test data for human pathogens such as Human Coronavirus, HIV-1, Hepatitis C, Legionella, MRSA and others. Based on all of this vendor-provided data, it looked pretty solid, except for, well, everything.
FIFRA does provide exemption from EPA registration in Subpart B (40 CFR 152.25) for minimum risk pesticides that contain what we might refer to as “natural ingredients” such as cedarwood oil, citronella, corn oil, peppermint, salt, thyme oil and numerous others. However, these exempted pesticides must meet six conditions, including that all of the ingredients must be listed on the label (no trade secrets allowed) and that the product “must not bear claims either to control or mitigate organisms that pose a threat to human health”. As soon as they hide the ingredients or make a “public health” claim (e.g., kills viruses), the 
product loses its exemption and must seek EPA registration, a large part of which is formal review of efficacy data. As for the claim of continuing to kill for 72 hours, this is simply false. There are no products, either exempt or currently on List N, that can legally make such a claim.
Exempt products such as the one described here can only legally claim to control the growth of algae (e.g., fish tanks), odor-causing bacteria, bacteria that cause spoilage or fouling (e.g., cooling towers, paint) or mold and to clean these types of agents from food contact surfaces. Anything more than that is simply untrue and is not allowed by federal law.
With demands for disinfectants at an all-time high, it is more important than ever to know exactly what you are buying and using. Unfortunately we cannot rely on the integrity of many of the salespersons and others pushing solutions that egregiously violate federal law and will not work. If you do not feel qualified to make detailed evaluations, contact a trusted advisor who can. There are many excellent products from which to choose, and you just have to be able to sort though the noise and chaos to get to them.
ABOUT THE AUTHOR:
Scott Harris, PhD is the Associate Director of EHS Services in the Austin, TX office of GDS Associates, Inc. and an adjunct faculty at University of Texas at San Antonio, University of Utah and UNC-Chapel Hill. Dr. Harris received his PhD in Environmental Science, with a specialization in Disaster and Emergency Management, from Oklahoma State University and holds degrees in Public Health and Geology from Western Kentucky University.
Scott Harris, PhD | CONTACT
512-717-8053 or scott.harris@gdsassociates.com