Disinfectant Labels: Take a Step Back

Author: Marc-Oliver Wright, MT(ASCP), MS, CIC, FAPIC

The annual conference of the Association for Professionals in Infection Control and Epidemiology, Inc (APIC) was held in person in June for the first time since 2019. The exhibit hall was teeming with a variety of products, while attendees collected samples of the latest and greatest, including (presumably) disinfectants. In evaluating a disinfectant, the first thing an IP will often do is study the label on the container. These production labels usually list active ingredients, kill claims, instructions for use, pertinent safety details, and contact time(s); but they do not tell the whole “story” of the product.

Production labels on containers of disinfectants are derived from the more comprehensive “EPA Master Label” which is readily available to anyone via the Pesticide Product and Label System (PPLS) on the EPA’s website.²

There is a difference between “what’s on the container” and  what is in the master labels . For example, the production label on a canister of PDI’s Super Sani-Cloth® wipes consists of approximately 1,099 words.¹ If one were to visit the EPA’s Pesticide Product and Label System² and enter the EPA registration number for Super Sani-Cloth wipes (9480-4), the user would find that the current (as of 8/9/2022) master label consists of 4,956 words .³ While the master label may contain redundancies, important details are also included.

Differentiations between production and master labels are often market-based and nuanced. The EPA spells out where and how these differences can occur. First and foremost, as indicated by the EPA on a master label footnote, “Statements in brackets are optional or instructional” and “Sequence and placement of phrases are optional unless specified in 40 CFR 156.10”³

Yet, some can be relatively important for IPs and end-users alike. For example, there is the issue of organism claims and wet/contact/kill time. A production label cannot claim to be effective against any organism not specifically listed on the master label. Relatedly, the overall wet/contact/kill time for the organisms  listed on the production label must be equal to or greater than the contact time listed on the master label for those organisms. Why “greater than?” Some organisms often have wet/contact/kill times less than others. Consider the following hypothetical example below:

Organism                                                       (Approved/Tested) Contact Time

Staphylococcus aureus                                              30 seconds

Pseudomonas aeruginosa                                         1 minute

HIV-1 (AIDS virus) [Strain HTLV-IIIB]                       30 seconds

Candida auris                                                              2 minutes

Streamlining the Process

Manufacturers will often select a singular wet/kill/contact time for the production label to streamline education, training, and practice. Although the above scenario suggests there are three different contact times, manufacturers can select a single time for the production label to simplify education and compliance for the end user. In this case, if all four organisms were listed on the production label, the wet/contact/kill time printed and instructed for use should be two minutes despite the fact that the majority of pathogens listed have a shorter contact time..

Alternatively, a manufacturer may opt to seek and attain master label approval for one or more organisms with longer wet/contact/kill times, but not include the organism on the production label at all and preferentially select an overall faster time. Continuing with the above example, if the manufacturer chooses not to include a microorganism claim, such as Candida auris, on the production label or marketing materials, thus opting to list only S. aureus, P. aeruginosa, and HIV, then they can claim that the product has an overall wet/contact/kill time of 1 minute.

It’s important to note that the label on the sample picked up at a conference does not tell the whole story. Thankfully, manufacturers list the EPA registration number, and the EPA makes the master labels readily available. Rather than love the smell and cost alone, end-users are well-advised to pursue the whole story via the master label to understand the nuances of the disinfectant.