When was the last time you thought about the residues from cleaning chemicals and the possible effect they have on you, your facility and its occupants?
Almost all of the chemical cleaning products we use to maintain our facilities are composed of some type of soap, oil or surfactant — either natural or manmade.
Residues often build up on surfaces over time, although those residues maybe be hidden by sealers, finishes and everyday soil, grease and grime.
One of the issues is that some types of cleaning chemicals are designed to bond with or attract dirt, so their residues continuously compound over and over again.
Residues aren’t given a lot of attention and, therefore, aren’t necessarily considered important.
But, the fact remains that, if a surface has residue of any kind on it — generally left behind after a cleaning event — the surface could still be harmful in one way or another.
Residues: Harmless Or Harmful?
A chemical residue, quite simply, is matter that is left on a surface after evaporation or insufficient rinsing occurs.
“Immediately after use in surface cleaning, and independent of whatever method is used to apply them, detergent molecules remain chemically unchanged,” says Dr. Jay Glasel, managing member and founder of Global Scientific Consulting LLC. “However, a small but finite amount of detergent remains on the surface. Detergents are then either rinsed off the surface being cleaned or — in all too many cases — remain as residue on the surface.”
Whether this residue is harmless or poses some sort of threat — either physically in the form of a slip-and-fall hazard or being harmful to one’s health — greatly depends upon the chemistry of the solution being used.
The more benign the chemistry you are using, the safer the residue that is left behind will be; the more toxic the chemistry is, the more harmful the residue will be.
Allen Rathey, president of InstructionLink/JanTrain Inc., adds that, “One problem with chemical residues is that they can become airborne and inhaled, perhaps with consequences for asthmatic, allergic or sensitive persons. When in the form of dry but aerosolized particulate, this can be true regardless of whether the substance is benign or not.”
As society becomes increasingly Earth-conscious and focused on being as green as possible, chemical manufacturers are responding with healthier chemicals, often making their products easier to break down in the environment.
This, however, actually poses a problem.
“The detergents used in commercial cleaning solutions used in the U.S. are strongly encouraged by the U.S. Environmental Protection Agency (EPA) to be ‘biodegradable.’ While many in the cleaning industry are aware of the advantages of biodegradability for cleaning products, they may not make the connection between biodegradability and its implication: That residues can form food sources for all microbials," explains Glasel.
At first glance, most residues cannot be seen, which inherently makes them more dangerous.
In a way, they are out of sight and out of mind.
There are, however, several indicators that one should look for to determine whether or not surfaces are becoming riddled with unwanted chemical residues.
- Slippery surfaces
If a surface, whether it be a floor or a countertop, feels slippery or slick after it has been cleaned, chances are good that a residue has been left behind.
Slippery surfaces lead to increased slip-and-fall risks, the cause of 15 percent of accidental deaths, according to the U.S. Occupational Safety and Health Administration (OSHA).
- Food for microbes
While you've just cleaned a surface, the particles that adhere to the surface due to residue will provide a food source for microbes feed on.
If allowed to grow, those microbes cause the surface to once again become contaminated and in need of further cleaning.
“While the exact mechanisms of the biodegradation process may differ from those in solution, adsorbed detergent and other organic molecules on surfaces can be used for bacterial growth,” offers Glasel.
- Biofilm “starter kit”
If microbes are allowed to exist on a surface, they may colonize, forming communities called biofilms.
Biofilms tend to thrive on environments where moisture and soil are in constant contact with a surface, notably foodservice areas, locker rooms, restrooms and other places of the like.
- Indoor air quality (IAQ) issues
Residues left on a surface can irritate those with allergies or other sensitivities such as asthma.
A key factor in sick building syndrome is HVAC and AC systems compromised by residues. While having a dirty or contaminated HVAC or AC system might not seem like it would be that big of an issue, the reality is these systems can cause much more harm than one might realize.
When HVAC and AC systems are compromised by residues they may then contaminate sterile surfaces, which is especially problematic in heathcare facilities.
- Issues with disinfection, sanitizers, enzymes and bleach
The idea that the application of a sanitizer can rid a surface of any bacteria present is not necessarily incorrect, but it can actually exacerbate the problem of residues.
In his article The Problem with Detergent Residues on Surfaces, Glasel points out, "The structure of a very widely used group of sanitizers, the benalkonium series, also known as quaternary amonium compounds (quats), is based on a permanently positively charged ion. If a surface is not thoroughly rinsed free of detergent residue prior to quat application, the quat becomes neutralized and the antimicrobial action will become inactivated. The complex detergent-quat residue that is then left provides even more nutrients for the growth of bacteria.”
The Root Of The Problem
If initially unaware of what dangers residues might hold, there is likely a similar lack of awareness when it comes to discerning if residues reside on surfaces.
Do surfaces feel sticky, tacky, slimy or greasy, even if they appear clean?
Residue is unseen at the onset, so a change in surface feel or texture is often an indication, as are any odors.
There are visual indicators as well: Over time, as residues are left unchecked and allowed to build up, you will begin to actually see the offending residue on various surfaces; soap scum in a shower is an example of this type of residue buildup.
Residue starts at a microscopic level where you cannot see it until it reaches a macroscopic level, or a level where it can be seen.
The way certain surfaces, especially flooring, are made can make them inherently more prone to attracting and collecting residues.
“Rapid resoiling of surfaces, either carpeted or hard, can also be an indicator of residue, since cleaning products are formulated to attract soil,” quips Rathey.
When trying to find a solution to this all-too-common problem, the immediate thought might be to simply eliminate the use of any products that would leave residues behind.
This is, unfortunately, easier said than done — and, it is not necessarily safe or hygienic.
“There is very little chemistry that is free of residues,” concludes Rathey. "The real solution to the residue issue is to use methods that actually rinse away cleaner. Some solvents and steam vapor systems are examples of residue-free chemistry. Completely water soluble and rinseable, soap-free products for carpet and hard floor care are a valuable part of the professional cleaner’s arsenal of residue-free cleaners.”
Issues occur with residues for a number of reasons, the first of which is the fact that some residues will make a surface act like an adhesive; particles of an organic nature, like dust, dirt, grease, grime, flesh and pollens, can act as a food source for mold and other microbes.
Residues pose not only a health and safety risk to building occupants, but they can also be one of the major factors behind why buildings degrade before their time.
Cleaning with environmentally preferable solutions, such as free-rinsing cleaners or equally as effective yet far kinder to the environment technologies such as steam vapor, are easy ways you can begin to eliminate these health and safety risks.
By cleaning a new building with free-rinsing cleaners from the start, residues wont have the chance to buildup; the more your older building is cleaned using these methods, the less buildup you will see over time.