The science behind quat binding and how it can be prevented
Quaternary ammonium chloride (quat) is an active ingredient in disinfectants that are used widely throughout the industry. These disinfectants are popular because of their effectiveness against germs, bacteria and viruses; their relatively low toxicity at proper dilution; low odors and; long shelf life.
When used properly, quat disinfectants can be very effective. But if used incorrectly, quat binding can occur, drastically reducing the cleaning efficacy.
Quat binding, also known as quay absorption, is still a relatively new and misunderstood issue in the jan/san industry. It is garnering more attention, however, because of its potential to negatively impact cleaning results.
The phenomenon of quat binding occurs when the active ingredient (quaternary ammonium chloride) becomes attracted to and absorbed into fabrics. The science behind how this happens is simple: Quats are positively charged ions and cotton and other natural textiles are negatively charged; positive attracts negative.
The result is that at least a portion of the quat does not end up on the surface it is supposed to be cleaning. In fact, one study found that the quat level of a disinfectant remaining on a cotton cloth placed in a solution-filled pail was decreased by 50 percent after soaking for just 10 minutes. That means the solution applied to the surface would contain only half of the parts per million (ppm) listed on the label.
“As soon as this phenomenon occurs, the quat disinfectant is off label and in violation of federal law,” says J. Darrel Hicks, BA, REH, CHESP, certified expert trainer and author of Infection Prevention for Dummies. “The worst part is that the disinfectant isn’t killing pathogens as it should and, in fact, may be producing microorganisms that are resistant to the disinfectant.”
Despite the troubling implications, many within the industry remain uninformed about quat binding. Hicks estimates that less than one-quarter of environmental services executives are aware of the problem. But even worse, some know about quat binding, and choose to ignore it.
“Unfortunately, many people look at the solution to dealing with quat binding as being too costly or unimportant,” says John Scherberger, BS, CHESP, REH, principal at Healthcare Risk Mitigation in Spartanburg, South Carolina. “Failure to recognize the importance of the negative affects of binding is careless and shows indifference to the health of their staff and building occupants.”
Jonathan Cooper, director of environmental and linen services at Health Central Hospital in Ocoee, Florida, only recently heard of quat binding after a vendor brought it to his attention. Like many in his position, he’s eager to learn more about preventing the problem.
“We spend a lot of money on cleaning supplies, so to render it infective is both a waste of money and an infection control issue,” says Cooper. “You think you’re cleaning, but you’re not really removing the bacteria you need to from the surface.”
Tips To Preventing Quat Absorption