Quat Binding

Quat binding happens because quats contain positively charged ions and the fabrics of many cleaning applicators contain negatively charged ions.

Has it ever occurred to you that the cleaning solutions—specifically, disinfectants—used in your facility may be losing their effectiveness as they are being used?

Here’s the problem. The active ingredients in some of these cleaning solutions, called "quats," are being absorbed by the wipes, mops, and cleaning cloths that are used to apply them. And not only are the active ingredients that kill germs and bacteria being absorbed by the cleaning cloths, for example, but they may also be pulled into the cleaning cloths. No matter how it is happening, what this is known as is "quat binding."

Quat binding happens because quats contain positively charged ions and the fabrics of many cleaning applicators contain negatively charged ions. While a perfect union can occur between people when two opposites attract, when it happens with disinfectants the results can be very problematic: the disinfectant loses its germ-killing power.

Just how serious is this problem? In one study, a cotton cleaning cloth was soaked in a disinfectant solution–filled pail for about ten minutes. After that time the quat levels of the solution were measured and were found to be cut in half. This means that only half of the bacteria- and germ-killing quats listed on the disinfectant’s label were still present. When this happens, the disinfectant is no longer as effective as its label indicates.

Worse, not only is the disinfectant no longer as effective in killing pathogens as it should be, but it also may be contributing to the growth of “microorganisms that are resistant to the disinfectant,” according to J. Darrel Hicks, author of Infection Prevention for Dummies. Why exactly this happens, Hicks did not clarify, but it is assumed that surface organisms essentially become immune to the disinfectant.

Quat binding can be a problem anywhere, but some of the biggest areas of concern are food preparation locations. According to Tara Miller, product manager at ITW Professional Brands, which makes a number of professional cleaning products for the commercial food service industry, “Fifty percent of the food service industry uses cotton rental towels or bar towels,” exactly the type of towels implicated in quat binding. She goes on to say that "some larger chain [restaurants] know about quat binding issues, but most are still in the dark about them."

According to Miller, the key reason the food service industry and people working in food preparation areas should be aware of quat binding is that, on an annual basis, an average of one in six people gets sick from eating contaminated food, and 3,000 people die each year from foodborne illnesses. Even if the food itself is safe to eat and properly cooked, following best practices to protect human health, when cooked food comes into contact with surfaces that are not properly disinfected and hygienically cleaned, even if thought to be so, the food can become contaminated. Quat binding can be the culprit for these contaminated surfaces.

Miller goes on to say that, along with the possibility of causing people to become ill, quat binding can be costly in another way, and that is pure dollars and cents. "[Administrators] are throwing money out the window on chemicals because they are [not working] or [not] being used properly," she says.

Addressing the Problem 

Miller and most public health officials suggest that the first step in addressing the health risks of quat binding is simply awareness. Facility managers and administrators in correctional and other types of facilities need to know that quat binding is a problem, along with how and why it is occurring. Once quat binding is understood, administrators can take the following steps to combat its effects:

• Use disinfectants with higher concentrations of quats; then even if some of the quats are absorbed by the cleaning cloth or mop, enough may remain to clean and disinfect a surface effectively.
• While cleaning professionals are usually taught to spray cleaners and disinfectants on a cleaning cloth first and then wipe the surface to be cleaned, to lessen the effects of quat binding it probably is best to first spray the surface to be cleaned and then wipe it. (Be sure and allow the disinfectant to set “dwell” on the surface a few minutes before wiping)
• Investigate cleaning procedures that do not require the use of cleaning cloths or mops at all. For correctional facilities, a recommended option is a spray-and-vac or no-touch cleaning system that applies disinfectant directly to a surface, rinses and then vacuums the area clean without the need for wiping or mopping.*

Administrators are urged to discuss the problem of quat binding with their janitorial distributors to find more solutions to this problem. What they may discover is that there is a trend evolving in the professional cleaning industry that may help address this and similar problems. The professional cleaning industry is moving away from cleaning cloths, buckets, and mops,. This is because we now know that these tools can spread germs instead of effectively removing them. Quat binding is just one more reason to shelve mops and cleaning cloths and look for other, more effective cleaning options.

COMPATIBILITY OF DISINFECTANTS WITH CLEANING TOOLS

Studies have demonstrated that there may be a reduction of efficacy when quaternary-based disinfectants bind with cleaning materials such as microfiber or cotton.  The most common disinfectant used for daily environmental surface disinfection today is quaternary ammonium chloride, commonly referred to as quats. Quats are often used because they offer a broad spectrum of pathogen kill, good surface compatibility, and are often the most economical option.

Quats are cationic or positively charged compounds.  Because of this, quats have a tendency to become attracted to cleaning tools or fabrics that have an anionic or negative charge.  One of the most common cleaning tool fabrics is cotton, which is a natural fiber that consists of 90% cellulose, and has a negative charge.  Another common fabric used in cleaning tools is microfiber.  Most microfiber cloths are made of a synthetic blend of polyester and nylon (polyamide) which also has a negative charge.  

When quat disinfectants are used with cotton or microfiber fabric, the positive charge on the quat aligns itself with the negative charge on the fabric and essentially neutralizes the activity of the quat. This may mean that the expected level of disinfectant is not being applied to a surface as it is wiped. The tendency of quats to bind with some fabrics is often referred to as “quat binding” or absorption. It has been shown that quat binding begins as soon as the cleaning tool is dipped into the quat solution.  This phenomenon can be eliminated by spraying the disinfectant directly onto the surface, using alternate disinfectant technologies or implementing disposable wipes into your cleaning protocol.