Carbon Footprint of Hand Sanitizer Measured: Hand Sanitizer Emissions Guide

Hand sanitizer is one of the most commonly used disinfectants, particularly in healthcare settings, and the carbon footprint of hand sanitizer has received much attention since the outbreak of the COVID-19 epidemic.

Hand hygiene is vitally important, but how does hand sanitizer measure up against conventional hand washing from an environmental perspective?

This article provides some quick insight into the environmental impact of hand hygiene practices. Continue reading to learn more about how to make sanitization more eco-friendly!

What Is the Carbon Footprint of Hand Sanitizer?

Calculating the carbon footprint of a product is a bit different, and the surest method is conducting a life cycle analysis that takes into account all emissions produced from “cradle-to-grave” (see the EPA’s “Design for the Environment Life-Cycle Assessments”).²¹

A cradle-to-grave analysis must account for three scopes of GHG emissions:

• Scope 1: Direct emissions from fuel combustion by owned facilities or vehicles
• Scope 2: Indirect emissions from purchased electricity
• Scope 3: Indirect emissions, both upstream and downstream, of product manufacture

When examining a specific product, scope 1 and 2 emissions can be calculated by estimating the amount of the company’s overall energy and fuel use allocated to the manufacture of that product (see “Scope 1 and Scope 2 Inventory Guidance”).¹⁶ Scope 3 emissions are more difficult to track, estimate, and report as it requires the company to understand the GHG emissions produced by their material suppliers as well as by the consumers of their products (see “Scope 3 Inventory Guidance”).¹⁷

During the COVID-19 epidemic, the use of hand sanitizer and other disinfectants reached an all-time high, leading researchers to take a closer look at the carbon footprint of hand sanitizer.¹⁹ There are two primary types of hand sanitizers in use today: those that are ethanol-based and those that are isopropyl-based.¹³

The carbon footprint of the finished product includes the emissions produced by manufacturing and transporting the separate ingredients, emissions from manufacturing plastic containers, emissions from employee commute and business travel, emissions and manufacturing waste, transport of finished product, as well as retail, use, and disposal of the product.

The outbreak of the coronavirus in 2019 brought hand hygiene back to the forefront of peoples’ awareness, encouraging researchers to conduct a life cycle analysis of hand sanitizers compared to conventional hand washing routines. A study conducted in Dublin, Ireland, and published in 2022 compared the life cycle of ethanol-based sanitizer, isopropanol-based sanitizer, bar soap hand washing, and liquid soap hand washing, analyzing environmental impact in many different domains.⁶

For the sanitizer, the study included the emissions from the raw materials, mixing, packaging, transportation, evaporation, and waste. For soaps, emissions from the raw materials, saponification, packaging, transportation, 40 seconds of room temperature tap water, every other day hand towel laundering, and plastic, paper, and water waste were included.⁶

Hand sanitizers contributed much higher rates of photochemical ozone formation, while soap and water washing contributed more to freshwater eutrophication. As for climate change, conventional hand washing with liquid soap, followed by bar soap and ethanol-based sanitizer produced the most CO₂e emissions.

For sanitizers, raw materials were the largest contributors to climate change, followed by packaging. The use of tap water and energy for laundry were significant in the carbon footprints of hand washing.

The results were for the entire population of the United Kingdom rather than on a product-by-product basis.⁶

An article published in the British Journal of Anaesthesia in 2023, reports that a single use of hand sanitizer generates approximately 0.9g of CO₂e compared to 9 g CO₂e for a single 20-second hand washing.¹⁴

Reducing the Carbon Footprint of Hand Sanitizer Spray

Because hand hygiene is so important in preventing the spread of illness and disease, reducing the carbon footprint of hand sanitizer and other hand cleansing methods should be a top priority.

When purchasing hand sanitizer:

• Bear in mind that isopropanol (isopropyl)-based sanitizers are less harmful to the environment.
• Look for brands that use natural, biodegradable ingredients, such as aloe vera, rather than glycerin or glycerol.
• Use the product completely before disposing of containers.
• Recycle the dispenser.

When purchasing hand soaps and washing hands with soap and water:

• Ensure that the soap product does not contain palm oil, a major source of deforestation.
• Choose products with natural, biodegradable ingredients.
• Purchase tablets or other refillable options to minimize plastics.
• Turn water on to wet and rinse hands, but do not leave water running while washing.
• Launder hand towels in cold water, using natural, biodegradable detergents.

What Is a Carbon Footprint?

The climate crisis the world is now facing is undeniable, and by now, everyone has heard the term “carbon footprint.” But what is a carbon footprint?

To understand what a carbon footprint is, a bit of information about climate change must first be highlighted. Climate change is a phenomenon that is receiving increased attention in recent years due to the obvious alterations in weather patterns, glacial melting, increased droughts, desertification and so forth (see “Basics of Climate Change”).⁴

These changes are largely the result of human activities, such as deforestation, plastic pollution, industrialization, etc. which release greenhouse gases (GHGs), such as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) into the atmosphere.

As the concentrations of GHGs in the atmosphere increase, they trap heat, producing a warming effect known as “The Greenhouse Effect.”¹⁰

Transportation, industry, and electricity use are the largest contributors to global warming (see the EPA’s “Sources of Greenhouse Gas Emissions”), but commercial and residential are responsible for 13% of U.S. GHGs and agriculture an additional 10%.¹⁸

Thus, every person, company, product, industry, country, and so on contributes to climate change.

The amount of GHGs contributed by a specific source is that source’s carbon footprint (see “Carbon Footprint Factsheet”).⁵

Carbon footprint calculation takes user input data about location, electricity used, fuel consumed, and waste produced, and uses that information to generate an estimate of the individual’s (or company, country, etc.) carbon footprint.

The number generated is represented as carbon dioxide equivalent (CO₂e) emissions, where various GHGs are scaled to CO₂ to give weight to their differential global warming potentials (see the EPA’s “Understanding Global Warming Potentials (GWP)”).²⁰

Carbon footprints for people, companies, and industries are usually calculated on a per annum basis, allowing comparisons from year to year that enable tracking and monitoring which changes produce positive outcomes.

The Importance of Hand Hygiene

It was a Hungarian doctor who first discovered and proclaimed the importance of hand hygiene. It was 1848 when Ignaz Semmelwis realized that maternal deaths were higher on the doctor-run ward where doctors would deliver babies after dissecting cadavers without cleansing their hands.

Although his discovery was not well-received at the time, it paved the way for better hygienic practices in future decades.⁸

Proper hand hygiene prevents the spread of infectious, and sometimes deadly, germs to humans, shared surfaces, and foods. It is extremely important to wash hands before and after preparing food, eating food, caring for the sick, treating a wound, using the restroom, handling pets, handling garbage, and coughing or sneezing.

According to the U.S. Centers for Disease Control and Prevention (CDC), proper handwashing entails wetting the hands with warm or cold water, lathering soap, and scrubbing all parts of the hands and wrists for at least 20 seconds before rinsing.²

Hand Sanitizer vs. Washing Hands for Best Hand Hygiene

When the option is available, should people opt for hand sanitizer vs washing hands? According to the CDC, no they should not.

The CDC reports that while sanitizer is quick-acting and is a great tool when conventional hand washing is not available, hand sanitizer is not as effective as soap and water. Hand sanitizer cannot remove dirt, grease, chemicals, and other substances the way soapy water can.

Hand washing with soap and water is also more effective against specific infectious germs that are known to be prevalent in healthcare and food service settings.¹

How To Make Homemade Hand Sanitizer

There are several reasons why someone might be interested in making homemade hand sanitizer.

Firstly, during the early days of the coronavirus outbreak, the availability of hand sanitizer was limited, and a lot of people set out to make their own products. Secondly, when making any homemade product, there is more control over the quality of ingredients added.

For example, an individual may opt to use organic aloe vera or even homegrown aloe vera.

Thirdly, there is the potential to cut down significantly on plastic waste with homemade products. By buying ingredients in large, recyclable containers and refilling dispensers, small plastics can be reduced.

Follow these very simple steps to make eco-friendly hand sanitizer that is safe and gentle on skin:⁹

1. Purchase 99% isopropyl alcohol (rubbing alcohol), 3% hydrogen peroxide, glycerin, and distilled water.
2. Add 4 cups of isopropyl alcohol to a clean container.
3. Add ¼ cup of hydrogen peroxide.
4. Add 4 teaspoons of glycerin.
5. Add 1 cup of distilled water and mix.

Other recipes replace the hydrogen peroxide, glycerin and water with aloe vera gel and mix 2 parts alcohol with 1 part aloe. Whichever recipe one chooses, it is important that the final product has at least 60% alcohol composition for efficacy.²²

Note, however, that the FDA advises against making hand sanitizer at home, as a homemade product is not guaranteed to be effective and there is also the potential for alcohol burns to the skin.¹⁵

How To Dispose of Hand Sanitizer Properly

To decrease individual, household, and product carbon footprint, it is essential that consumers know how to dispose of hand sanitizer properly. According to the Environmental Protection Agency (EPA), alcohol-based hand sanitizers are considered hazardous waste due to their flammability, and therefore, they must be disposed of through the proper avenues.¹³

A container of hand sanitizer that is completely empty can be recycled for curbside pick-up, but partially empty or unopened bottles should never be dropped in household recycling or trash bins. Instead, these containers should be taken to a local hazardous waste facility for disposal (see EPA’s “How Do I Find Hazardous Waste Management Facilities in my Area?”).^12,13

Hand hygiene is incredibly important, particularly in industries such as healthcare, where inadequate hand hygiene can spread life-threatening germs to individuals who are immunocompromised or otherwise medically vulnerable.

Because hand sanitizers are so instrumental in preventing the spread of infectious germs within these settings (and many others), it is imperative that manufacturers and consumers evaluate available data on their environmental impact.

Manufacturers can use this information to devise more sustainable formulas and packaging to reduce the carbon footprint of hand sanitizer.

Frequently Asked Questions About the Carbon Footprint of Hand Sanitizer