Disinfectants and COVID-19

Disinfectants are valuable tools for controlling human pathogens, including SARS-CoV-2 (the virus responsible for COVID-19), but only when used correctly

DISINFECTANTS ARE PESTICIDES

To use any pesticide correctly, read and follow the instructions on the product label exactly. The label is the law!

Safety guidelines for using disinfectants and surface sanitizers:

ALWAYS follow the label directions.

ALWAYS use any personal protective equipment (PPE) specified by the label.

ALWAYS store according to label directions, and keep out of reach of children and pets.

NEVER use a disinfectant or other pesticide product in a manner inconsistent with its labeling.

NEVER exceed label concentration or application rates.

NEVER deliberately inhale, swallow, inject, or apply disinfectants to skin or mucous membranes.

  • Many disinfectant products are highly corrosive.
  • None are safe to go directly in or on people or animals.
  • Use U.S. Food and Drug Administration (FDA)-approved sanitizing wipes for hands, not Environmental Protection Agency (EPA)-registered disinfectant wipes.

NEVER combine bleach with ammonia or any acid (including vinegar). Doing so can release deadly gases.

  • Don’t mix disinfectants.
  • Avoid DIY disinfectants.

NEVER treat fruits and vegetables at home with disinfectants. Doing so could result in poisoning. Wash produce only in clean water.

NEVER use products to control microbial or other pests that have not been registered by the EPA and, in Maine, the Maine Board of Pesticides Control (BPC).

DISREGARDING LABEL DIRECTIONS IS DANGEROUS AND A VIOLATION OF FEDERAL LAW.Graphic depicting the directions for use on an aerosol disinfectant with the text 'read the label'

Disinfectant poisonings and injuries can result in the following:

  • Death
  • Blindness
  • Permanent injury to the lungs and other organs
  • Compromised health that could increase susceptibility to pathogens

Beware of fraudulent pesticide claims related to SARS-CoV-2:

Unregistered disinfectants claiming to protect against the virus are being marketed in the U.S. The efficacy and safety of these products are unsubstantiated and their use and sale is illegal. Even pesticide products exempted from registration by the EPA because they are formulated with minimum risk active ingredients (cinnamon, citric acid, garlic oil, peppermint oil, rosemary, sodium chloride, etc.) cannot claim to control any human pathogen*. If they do, they are illegal to use or sell. Natural ≠ safe.

Only EPA-registered disinfectant products that have met the EPA criteria for use against SARS-CoV-2 can be expected to control the virus on surfaces. The Maine Board of Pesticides Control maintains a PDF list of these products that are legal to use in Maine. It can be found on the BPC homepage.

Because SARS-CoV-2 is a new pathogen and the efficacy testing of antimicrobial pesticides can take years, disinfectants meet the EPA criteria by demonstrating that they control established coronaviruses or established viruses that are more difficult to kill. For this reason, the EPA list of disinfectant products for use against SARS-CoV-2 (List N) names one or more established viruses for each approved product. Users should check this list and follow the label instructions for the product’s designated established virus.

* In Maine, all pesticide products must be registered with the Maine Board of Pesticides Control, including minimum risk (25(b)) products, regardless of their claims.

Factors that affect the safety and effectiveness of disinfectants and surface sanitizers:

Surface type. Most disinfectants work best on hard, nonporous surfaces. The disinfectant must contact the virus to be effective. Rough, porous, and soft surfaces can allow microorganisms to shelter where the product doesn’t easily reach.

  • The labels of some disinfectant products prohibit their use on food contact or other specific surfaces.
  • Many disinfectants must later be rinsed from food contact surfaces and toys with potable water.
  • Many disinfectants will damage some surfaces.

Surface cleanliness. Disinfectants are most effective on clean surfaces. Organic matter shelters pathogens and reduces the activity of some disinfectants.

  • Surfaces may need to be pre-cleaned before disinfection.
  • Organic matter interferes with chlorine products, reacting with chlorine and reducing its concentration.

Contact time. Disinfectants take time to control microorganisms effectively after application. This interval is called contact time and varies by disinfectant and the target pathogen. The treated surface must be wet with the disinfectant during this time. Most approved disinfectants are believed to control SARS-CoV-2 with 10 minutes of contact time. However, some have shorter contact times and a few have longer.

  • EPA’s List N includes the contact time for each product to kill the virus.

Formulation. Generally, ready-to-use products are less hazardous since users aren’t exposed to concentrated product during the mixing stage. They’re also easier to use. Concentrated products must be diluted as directed by the label.

  • Concentrated liquids are often highly corrosive. Corrosive disinfectants can burn the skin and cause irreversible eye damage. Always wear all PPE indicated by the label. Dilute as directed.
  • Aerosols (ready-to-use) are suspensions of fine particles or droplets in air that usually come in a spray can. Make sure to shake well before applying if directed by the label as this mixes the suspension inside. Users should remain especially mindful of inhalation exposure when applying an aerosol.
  • Sprays (ready-to-use) are liquid disinfectants applied as drops through the air. Inhalation exposure is less likely than with smaller aerosol droplets but still a concern. Users should take care that the spray is applied only to the target site and doesn’t stray onto food, people, or prohibited surfaces.
  • Wipes (ready-to-use) are single-use cloths saturated with liquid disinfectant. They are very easy to use and pose little risk of inhalation exposure. However, they are easily confused with sanitizing hand wipes or worse, baby wipes. Disinfectant wipes are for environmental surfaces only, NOT hands or other body parts.

Concentration. In general, higher concentrations of disinfectant are more effective, but never exceed the highest concentration prescribed by the label. The proper concentration varies depending on the product, the target pathogen, and sometimes the surface or situation.

  • Use the dilution indicated on the label for the established virus designated on List N.
  • Do not use a higher concentration than directed for the virus. It’s unnecessary, more hazardous, and (if above the maximum concentration allowed by the label) illegal.
  • Do not use a lower concentration than directed for the virus. SARS-CoV-2 may survive a lower concentration than is directed.

Dilution water. For disinfectants that must be diluted, be aware that water hardness and acidity/alkalinity (pH) can affect the activity of some disinfectants. Some antimicrobial product labels set a water hardness limit and give an optimal pH range. Bleach does not lose efficacy diluted with hard water.

Application method. The application method for a given product may vary, depending on the use site, target pathogen, and target surface.

  • Follow the product directions for use site (home, institution, medical facility, etc.).
  • Follow the product directions for the established virus given on List N.
  • Follow the product directions for the target surface.

What’s the difference?

Sanitizers vs. Disinfectants

Regulators and manufacturers often categorize antimicrobials by the type and the degree of control they provide. The pesticide label describes what an antimicrobial product does, and often what it does not do. Public health antimicrobials list the specific pathogens they’ve been proven to kill. Labels describe the surfaces and circumstances on/in which they will be effective and how to apply them for each use. Whether an antimicrobial pesticide acts as a sanitizer, disinfectant, or sterilant may depend on its use. Some act as all three at different concentrations.

  • Sanitizers. These chemicals reduce the number of microorganisms on surfaces, often including food contact surfaces. These are NOT the same as hand sanitizers.
  • Disinfectants. These chemicals kill or mitigate the growth of bacteria, fungi, and some viruses. They may not kill bacterial spores. They shouldn’t be used on food contact surfaces. Most disinfectants require 10 minutes of contact time to kill most microorganisms.
  • Sterilants. These chemicals kill bacteria, viruses, and fungi, including spores. They’re used primarily for sterilizing heat-sensitive medical and laboratory equipment.

Disinfectants and Surface Sanitizers vs. Hand Sanitizers and Other Antiseptics

Although disinfectants, antiseptics, and antibiotics are all antimicrobial agents, they are NOT interchangeable. Disinfectants and environmental surface sanitizers are antimicrobial pesticides. Hand sanitizers are drugs.

  • Antimicrobial pesticides are NEVER used in or on a living person or animal.
  • The EPA, under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), regulates antimicrobial pesticides.
  • Antimicrobial agents used in or on a living person or animal are drugs.
  • The FDA, under the Federal Food Drug and Cosmetic Act (FFDCA), regulates antimicrobial food additives, antibiotics, antiseptics (including hand sanitizer), and other drugs.

Additional Disinfectant Resources:

www.epa.gov/coronavirus

npic.orst.edu/ingred/ptype/amicrob/covid19.html

www.maine.gov/dacf/php/pesticides/index.shtml

The information here was adapted from UMaine Cooperative Extension’s Microbial Pest Control pesticide applicator manual and pesticide safety statements from Cornell Cooperative Extension’s Pesticide Management Education Program. Other sources include materials from the EPA, CDC, FDA, the National Pesticide Information Center, and the Maine Board of Pesticides Control. 

Disclaimer

The information provided on this page is pesticide safety information, not medical advice.

This information is intended for the general public. Licensed applicators, food producers, water treatment operators, healthcare professionals, government employees, etc. may find some exceptions to the guidelines above, if the product label allows.

Pesticide safety information may change over time. The information above is provided for educational purposes only and was published in 2020.

Although pesticides can be an essential tool in pest management, the improper use and disposal of these chemicals present a continuing risk to humans, animals, and the environment. It’s important for applicators to understand that pesticide safety is not only about protecting themselves — it’s also about protecting our domestic and wild animals, the environment, our landscapes, and our communities.

Misuse of pesticides can result in, or contribute to, serious injury, illness, or death. Cooperative Extension does not guarantee the safety or effectiveness of any product or practice. Users of any pesticides, and Extension’s educational materials, do so at their sole risk and assume all risk from using such pesticides and materials, whether they follow recommendations or not. The user bears all responsibility for resulting damages to property, human health, or the environment. Cooperative Extension and the University of Maine System shall not be responsible for any damages including, but not limited to, any and all damage or loss to real or personal property, personal injury or death, resulting from the negligence of cooperative extension, the university, its trustees, faculty, agents, employees or volunteers.

Always follow directions on pesticide labels! Failure to do so violates federal law. Application timing and proper calibration are as important as using the right product.

Cooperative Extension makes no warranty or guarantee of any kind, expressed or implied, concerning the use of any stated products. Trade names are used for identification only; no product endorsement is implied, nor is discrimination intended.

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