9 Dos and Don’ts of COVID-19 Disinfecting
There’s a reason why the cleaning section of your local grocery store has likely been empty: Americans are disinfecting their homes in huge numbers during the COVID-19 pandemic.
Sales of aerosol disinfectants like Clorox and Lysol grew by more than 385 percent in the first week of March 2020 compared to the same period in 2019, according to Nielsen. More ominously, calls to the nation’s poison control centers increased by 20 percent during the first quarter of the year. Specifically, 45,550 calls related to cleaner and disinfectant exposure were made from January through March 2020, compared to 37,822 in 2019, according to the Centers for Disease Control and Prevention.
The uptick in poison control calls has resulted primarily from exposure to bleaches, nonalcohol disinfectants and hand sanitizers, with inhalation representing the main form of exposure.
“Any time there's a change in normal routine, that's when we see increased risk of accidental exposure,” says Daniel E. Brooks, MD, Medical Director of Banner Poison and Drug Information Center in Phoenix.
Given the current environment with millions of Americans staying inside, day after day, it’s especially important to keep an eye on how we’re using these powerful cleaning chemicals.
Do we really need to clean so much? It’s normal to want to clean as much as you can during the pandemic, but do we need to scour our entire home?
Every single surface doesn’t need to be disinfected, notes Elizabeth Scott, PhD, associate dean and professor at the College of Natural, Behavioral and Health Sciences at Simmons University in Boston.
Instead, Scott recommends an approach called “targeted hygiene,” which entails focusing on areas that are most involved in the transmission of disease. In layperson’s terms, that means addressing common-touch surfaces such as:
Counters and tabletops
Bathroom fixtures and toilets
Phones and tablets
And if any other surfaces become visibly dirty, disinfect them, too, just to be safe.
Cleaning vs. disinfecting Before you bring out the disinfectants, the first step is to clean the area in question. Cleaning means using soap and water to remove germs and dirt from surfaces. While taking this step does not kill germs, it can help lower their numbers and the risk of them spreading. Plus, a buildup of dirt can reduce the effectiveness of disinfectants.
Disinfecting comes next and involves using products to kill germs. This process does not necessarily remove grime from surfaces (which makes the first step important), but when you kill germs on a surface after cleaning, you lower the risk of spreading infection even more.
“All told, disinfection implies cleaning followed by the use of a chemical that reduces or eliminates bacteria and viruses,” says Scott. Bleach, ammonia, hydrogen peroxide and 70 percent rubbing alcohol are disinfectants that can be used safely at home, as long as you follow these guidelines:
Do clean areas with soap and water before disinfecting—and rinse after. Depending on the surface you’re disinfecting, it’s often a good idea to rinse with water afterwards. For example, bleach and peroxide can discolor or damage certain types of countertops if the chemicals are left to stand on them. Because bleach can corrode metal, it’s also advisable to use other products on faucets and stainless steel.
Do follow directions on cleaners and disinfectants. Dr. Brooks says these are comprehensive and can help you use products safely and effectively. Unsure of how to handle electronics? Wipes or sprays containing at least 70 percent alcohol can disinfect screens. Just remember to dry your gadgets thoroughly so liquids don’t remain on them.
Don’t use disinfectants in close spaces, like closets. Exposure to cleaning product fumes can contribute to respiratory distress. To prevent this, make sure there is a good amount of ventilation where you’re cleaning. If there isn’t a window that can be opened, consider running a fan to promote air movement.
Do wear rubber gloves. They help protect your skin from harsh chemicals. Wash your hands with soap and water for 20 seconds after you take the gloves off.
Don’t disinfect foods. “Even before COVID-19, people were cleaning food or fruits with stuff like hydrogen peroxide, and all of that is completely unnecessary. There's no science behind it,” Brooks says. “It’s potentially harmful. Cleaning fruits and vegetables and foods with hydrogen peroxide does not promote health.”
That said, if you have a wooden or plastic cutting board that can’t be placed in the dishwasher, you can disinfect it with a solution of 1 tablespoon of unscented chlorine bleach per gallon of water (more on mixing ratios below). Saturate the surface with the solution, let it stand for several minutes, rinse thoroughly with water, then air dry or dab with paper towels.
Don’t use vinegar solutions to disinfect. “There is plenty of evidence that so-called home remedies such as vinegar and water are not effective at disinfecting inanimate surfaces,” Scott says. “Using them can leave people with a false sense of security.” Although some research suggests that vinegar cleans surfaces and helps kill some bacteria, it doesn’t do so as effectively as commercial cleaners.
So, if you’re cleaning things like mirrors, break out the vinegar solution. But, Scott notes, “to safely and effectively disinfect an area such as a food prep surface or a common-touch surface, the recommendation is to use the appropriate dilution of household bleach or other disinfectant such as Lysol, following the label recommendations.”
Don’t mix chemicals. “Combining chemicals poses a risk of unknown synergistic effects,” Brooks says. In other words: “You could actually start a chemical reaction that generates heat or gas, which could lead to eye injury or pulmonary or lung injury.”
Some common chemicals you should never mix include:
Ammonia (often found in glass cleaner and some paints) and bleach
Bleach and any acid (including vinegar; any lime, calcium or rust removal products; glass or toilet or drain cleaners; and dishwashing detergents)
Bleach and rubbing alcohol
Hydrogen peroxide and vinegar
Hydrogen peroxide and bleach
Simply put, don’t mix any cleaning chemicals or disinfectants with anything besides water.
Do dilute concentrated products with water. “The safest way to do it is to add the cleaning agent into water,” Brooks says. Many product labels explain the product-to-water ratio to use, but for a basic bleach disinfecting solution, mix 5 tablespoons (or 1/3 cup) of bleach for each gallon of water, or use 4 teaspoons of bleach per quart of water. Just remember to use your solution within 24 hours. The bleach will fade in strength and can cause certain plastic containers to deteriorate in the meantime.
Do use common sense. “You can prevent injuries and exposures just by using your head,” Brooks says. Needless to say, only use household cleaners and disinfectants on surfaces in your environment, and never eat, drink or inject them. And always keep chemicals away from children.
If you have any questions about the safety, use or handling of any chemicals, don’t take a chance—call Poison Control at 1-800-222-1222 for more information.
Medically reviewed in May 2020.
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