About a year ago, we posted a blog on long-lasting or residual antimicrobial product claims. Since then, there have been some significant developments. At the time, the Environmental Protection Agency (EPA) did not have a method to approve long-lasting virus claims for these types of products. In the midst of the pandemic and with confusion about disinfection rampant, many companies improperly advertised products that supposedly provided residual kill against SARS-CoV-2 on surfaces. As the pandemic continued, the EPA recognized the importance of residual efficacy claims in general and for viruses in particular, and they have since made two important updates: (1) the EPA now allows residual virus claims on product labels, and (2) the EPA released guidance on how to add a new type of residual claim to product labels, called “supplemental residual antimicrobial” claims (more on this below). This article will help you sort through the new guidance on residual or long-lasting claims.

What types of EPA-registered residual efficacy claims can a product have and what do they mean?

Here’s how we interpret the EPA’s updated guidance on adding residual claims to product labels.1 There are three types of residual, or long-lasting, claims that you may encounter on product labels (Table 1). These include residual self-sanitization, residual self-disinfection, and supplemental residual antimicrobial activity. Each of these product claims requires data submission to the EPA and approval before they can be listed on a product’s label. These products are also tested for durability to make sure that they aren’t removed during normal cleaning procedures.

Products with residual self-sanitization or self-disinfection claims also have regular disinfection claims, meaning that they kill bacteria and/or viruses on contact. Residual self-sanitization and residual self-disinfection claims are very similar. The key difference is that residual self-sanitization claims are only valid for bacteria, while residual self-disinfection claims can be obtained for both bacteria and viruses. To meet the criteria for a residual self-sanitization claim, products must demonstrate 99.9% kill of bacteria on surfaces within a 10-minute contact time, and last for up to 24 hours following application. To meet the criteria for a residual self-disinfection claim, products must demonstrate 99.999% kill on surfaces for bacteria or 99.9% kill for viruses, within a 10-minute contact time, and last for up to 24 hours on surfaces.  

Products with a supplemental residual antimicrobial claim may not kill microorganisms when first applied to surfaces but do provide microorganism kill within a two hour contact time, and continue to provide kill for up to weeks or months. However, because the level of kill is significantly lower than that of a disinfectant, these products can only be used as a supplement to EPA-registered disinfectants. According to the EPA, this means that you will still need to use an EPA-registered disinfectant for regular surface disinfection.

Table 1. EPA-registered residual product claims

ClaimDescriptionWhat to Look for on LabelProduct Example
Residual self-sanitizationProduct kills 99.9% of bacteria on surfaces for up to 24 hours following application. Must demonstrate residual kill within a 10-minute contact time.“residual sanitization” or “residual sanitizer”Spray product that disinfects when applied and continues to kill 99.9% of bacteria up to 24 hours after application.
Residual self-disinfectionBacteria: product kills 99.999% of bacteria on surfaces for up to 24 hours following application. Viruses: product kills 99.9% of viruses on surfaces for up to 24 hours following application. Must demonstrate residual kill within a 10-minute contact time.“residual disinfection” or “continuous disinfection”Spray product that disinfects when applied and continues to kill 99.999% bacteria for up to 24 hours after application.
Supplemental residual antimicrobialProducts with this claim are eligible to be used as a supplement to routine application of EPA-registered disinfectants. These products are not disinfectants and cannot be used as a replacement for regular disinfection. Continues to kill 99.9% of bacteria and/or viruses for up to weeks or months. Must demonstrate residual kill within a 2-hour contact time.“Kills 99.9% of Staphylococcus aureus within 2 hours of exposure when used as part of a comprehensive infection control program/protocol”Copper-impregnated surfaces, paints

How do I determine whether a product has EPA-registered residual claims?

Here is how to find and search a product’s master label to determine which residual claims a specific product carries:

  1. Navigate to the EPA’s Pesticide Product Labeling System (PPLS) website.2
  2. Enter the product’s EPA registration number into the field labeled “EPA Registration, Distributor Product, or Special Local Need Number:” and click “Search.” Companies should be able to provide this number to you, or it may appear on their product website. An example of an EPA registration number is “67619-38.”
  3. Open the most recent master label. The EPA includes the full history of master labels for each product, but only the most recent one will have all of the currently approved claims.
  4. Search the label for the key terms listed in Table 1. Terms like “residual disinfection,” “continuous disinfection,” “residual sanitization,” or “residual self-sanitizer” must appear on labels that have approved residual self-sanitization or residual self-disinfection claims. Read the terms of the claim, including how often the product must be reapplied.

Which residual antimicrobial products can I use against SARS-CoV-2?

For a list of residual products that can be used against SARS-CoV-2, the EPA recommends searching EPA List N: Disinfectants for Use Against SARS-CoV-2 (COVID-19)3 for products with the formulation type “residual”. Note that supplemental residual antimicrobial products will not appear on List N, although they may appear in the EPA’s supplement to List N.4 And finally, note that if you see products that have “static” claims like “bacteriostatic,” “mildewstatic,” or “fungistatic,” these are not the same as residual disinfection claims. A “static” claim is for non-public health uses and means that the product inhibits the growth of bacteria or fungi on surfaces, but doesn’t kill those organisms for a certain length of time after application.

For more information on the new residual product guidance, see the EPA website.1

References

1. Interim Guidance – Review for Products Adding Residual Efficacy Claims | Pesticide Registration | US EPA https://www.epa.gov/pesticide-egistration/interim-guidance-review-products-adding-residual-efficacy-claims (accessed 2021 -06 -09).
2. Pesticide Product and Label System | US EPA https://oaspub.epa.gov/apex/pesticides/f?p=PPLS:1 (accessed 2021 -06 -09).
3. List N Tool: COVID-19 Disinfectants | US EPA https://cfpub.epa.gov/wizards/disinfectants/ (accessed 2021 -06 -09).
4. List N Appendix: Supplemental Residual Antimicrobial Products for Coronavirus (COVID-19) | Pesticide Registration | US EPA https://www.epa.gov/pesticide-registration/list-n-appendix-supplemental-residual-antimicrobial-products-coronavirus (accessed 2021 -06 -09).