Antimicrobials

Antimicrobials are associated with a wide variety of health harms and in many applications may have little or benefit.

What are they?

Antimicrobials are chemicals added to products with the intent to kill or inhibit the growth of microbes, including viruses. They are often marketed as antibacterial, antiviral, or anti-odor. Antimicrobials of concern include halogenated aromatic compounds, nanosilver, and quaternary ammonium compounds (QACs or quats), such as benzalkonium chloride and benzethonium chloride.

Where are they found?

Uses include cleaning and personal care products, clothing and other textiles, building materials, and high touch surfaces. They are also found in some food storage containers, kitchenware, school supplies, exercise mats, and electronics. Learn more about products that may contain antimicrobials.

What are the health concerns?

Antimicrobials may have adverse effects on beneficial microorganisms and other living things. For example, triclosan can disrupt hormone functioning and is associated with developmental and reproductive effects, and allergen sensitivity. Quats are associated with asthma, skin irritation, and adverse respiratory, nervous system, immunological, reproductive and developmental effects. Many antimicrobials are associated with antibiotic resistance.

How are we exposed?

Exposure can occur through inhalation, skin contact, and ingestion of contaminated dust. Babies, who are especially vulnerable to toxics, can be exposed in the womb and later from nursing. Triclosan has been found in three-quarters of the U.S. population and in nearly all breast milk samples tested. Recent research has identified over a dozen quats in human blood.

What are the environmental concerns?

The current high-volume use of antimicrobials is causing widespread contamination of the environment and wildlife. When products containing antimicrobials are washed down the drain the chemicals can be released to aquatic environments. Once in the environment, most are toxic to aquatic organisms and some bioaccumulate in marine food webs. Further, many antimicrobials persist in sludge from wastewater treatment that may later be applied to agricultural soil and landscaping.

Should they be used?

The perceived health benefits of antimicrobials in most consumer products are not supported by research. In fact, overuse of antimicrobials may contribute to increased microbial resistance to antibiotics or disinfectants. Washing hands with soap and water is as effective at preventing the spread of germs.

In September 2016, the FDA stopped the use of triclosan, triclocarban and many other antimicrobials in hand soaps and body washes. However, the substitutes were other antimicrobials of concern such as quats, whose use is increasing.

Both the World Health Organization and Centers for Disease Control and Prevention discourage large scale spraying with disinfectants due to lack of benefit and the potential for harm.

What Can You Do?

Avoid products that are advertised as “antimicrobial”, “antibacterial”, “antiviral” or “anti-odor”. Most alcohol-based hand sanitizers do not contain antimicrobials of concern and should be safer.
Avoid products with triclosan, triclocarban, quats (often ending with –onium chloride) or nanometals listed on the ingredient label.
Select products with the safest ingredients and use them only when necessary.
Tell manufacturers, retailers, and government agencies you want products without antimicrobials.

Resources

Notable Reports

Quaternary Ammonium Compounds: A Chemical Class of Emerging Concern – 2023 – This critical review details how QACs are increasingly marketed and used in home, healthcare, education, and workplace settings despite the availability of safer alternatives and limited evidence of reduced disease transmission.
Quaternary Ammonia Compounds in Disinfectant Products – 2024 – This review calls for ongoing evaluation of QACs’ environmental impacts, particularly in the context of their widespread use and potential to promote antibiotic resistance and disrupt wastewater treatment processes.
Joint Statement on Antimicrobials in Building Products – 2021 – This statement by leading green building organizations, architects, and scientists, responding to COVID-19 generated demand for antimicrobials, warns that building materials with added antimicrobials have no proven health benefit—and may be harmful.
Biomonitoring California Scientific Review of Quaternary Ammonium Compounds – 2021 – Biomonitoring California’s Scientific Guidance Panel voted unanimously to include the entire class of QACs on their priority chemicals list, a first step towards their possible regulation.
The Florence Statement on Triclosan and Triclocarban – 2017 – This consensus statement, signed by over 200 scientists, documents the potential harms and lack of benefit of the antimicrobials triclosan and triclocarban.
Adverse Effects of Nanosilver on Human Health and the Environment – 2019 – This review warns that repeated exposure to even safe doses of nanosilver through consumer products could lead to health harms. It also discusses how nanosilver can enter and disrupt aquatic ecosystems and the food chain.

Fact Sheets

Overuse of antimicrobials in gyms – Gym patrons should use soap and water or Safer Choice certified cleaning products rather than disinfectant sprays or wipes.
Antimicrobials in Consumer Products & Building Materials – The Green Science Policy Institute recommends avoiding the use of chlorinated antimicrobials, quaternary ammonium compounds, and nanometals due to their potential for harm and, in many cases, lack of proven benefit.
When and How to Clean and Disinfect a Facility – The CDC outlines guidance for safely and properly using disinfectants for surfaces in community settings (offices, gyms, businesses, and community centers).
Safe, effective cleaning & disinfection for businesses – San Francisco Environment provides helpful tips for cleaning and disinfection. It also offers a web tool for identifying safest COVID-19 disinfectants.
Disinfectant Overkill Focus on Quats – Women’s Voices for the Earth provides health and policy information about ammonium quaternary compounds, commonly found in household cleaning products.
Triclosan – Biomonitoring California recommends avoiding personal care products that list triclosan on the label, unless there is a medical reason for using them.