Yes, as we’ll cover, dry cleaning is not environmentally friendly.
To make it clear what we’re talking about here, dry cleaning is considered to be the cleaning of any fabric or item of clothes which uses a solvent other than water to achieve this goal.
This would include detergent, fabric softener, stain removers, etc., but namely, for dry cleaning services, the chemical of concern is perchloroethylene, sometimes referred to as tetrachloroethylene, PERC, or PCE.
It’s a type of manufactured solvent, meaning it is designed to dissolve other substances, in this case, dirt and grease.
In this article, we’ll discuss this and the wider implications of dry cleaning and look at some potential alternatives.
How Does Dry Cleaning Affect the Environment?
PERC is the most common solvent used in traditional dry cleaning.
Although research explains that it’s being phased out of use in most residential dry-cleaning facilities, it is still in use but just to a lesser degree.
Newer washing and drying machines that use less PERC than older models are the only ones allowed in residential buildings.
But traditional dry cleaning stores and commercial properties still use PERC as their primary solvent without these restrictions.
And given that there were more than 21,000 of these properties in the US as of 2019, it remains a controversial issue.
But that’s not all: in terms of the environmental life cycle of this process, there’s also the means of cleaning and what resources are expended.
For instance, resource consumption, pollution, emissions, and finally, the effects of PERC are also considered here.
1. Resource Consumption
As a process, dry cleaning uses less water than laundry washing. As the name implies, in dry cleaning, little to no water is used in the process.
The solvents, such as PERC, do the heavy lifting in combination with the machine during the washing cycle.
Here, the solvent lifts the stains and dirt from the clothing as it is revolved around the drum and then is filtered out along with these materials before being drained completely.
The relative heat for this process is low at around 75 to 80° Fahrenheit (24 to 27 °C) but will increase during the drying process to around 120 to 150°F (49 to 66 °C).
The dryer uses an exhaust pipe to manage this heat and a refrigerated condenser or cooling unit to evaporate any remaining liquids.
For these reasons, the overall process, while low in water expenditure, is relatively high in energy use as compared to normal laundering.
For instance, studies estimate that dry cleaning uses 58.6 kWh per 100 kg of clothing, whereas wet cleaning only uses 20.5 KWh per 100 kg.
And where the water consumption of laundry machines in the US is approximately 144 L per wash cycle, this is considerably different from dry cleaners, which use almost no water.
However, though, this doesn’t account for the effects on the water supply as a whole, which we will discuss below.
2. Water Pollution
After a dry cleaning cycle has been completed, the machine needs to filter out the remaining solvent from the clothes.
And although little water goes in, 660 gallons (roughly 2498 L) of hazardous waste from dry cleaners are expelled each year.
And although there are forms of remediation, such as in-machine filters and technologies, this doesn’t seem to be enough to mitigate the risk of PERC ending up in our water supply.
For instance, according to the above study, PERC has been found to be present in 25% of water supplies in the US.
It’s a highly volatile chemical that transforms from a liquid to a vapor when it’s exposed to the atmosphere.
This allows it to travel through water, air, and soil in many ways, such as:
- through precipitation of PERC-contaminated air into rain
- through poor disposal practices where it goes directly into water supplies
- through chemical spills and leaks into the soil and groundwater.
And according to research, the result can pose serious threats to aquatic life, such as toxicity for invertebrates, fish, and aquatic plants.
But just as crucially, if it’s in our water supplies, humans are also at risk.
It’s a skin irritant and neurotoxicant, meaning it can cause nerve damage, as well as being a cancer-causing agent, and can interfere with liver, kidney, and reproductive health.
3. Air Pollution and Greenhouse Gases
In addition to the highly volatile nature of PERC, giving it power to disperse into the atmosphere, its structure as a hydrocarbon can also contribute to global warming.
Hydrocarbons are products that are derived from petroleum sources and have the status of VOCs (volatile organic compounds).
As the EPA explains, these VOCs can create photochemical smog as they mix with sunlight and other chemicals in the atmosphere.
The smog can have a warming effect by increasing the concentration of pollutants in the atmosphere that can trap heat, like CO2, which results in global warming.
Another effect of this smog is that because it can trap heat near the atmosphere’s surface.
The University Corporation for Atmospheric Research warns it can melt the ice in the Arctic regions, which raises the planet’s surface temperature, again contributing to the rate of global warming.
VOCs also affect air quality both inside and outside the home.
As the American Lung Association highlights, VOCs not only pollute the air outside but can also cause irritation and respiratory issues inside people’s homes.
As we mentioned, PERC isn’t the only component of dry cleaning, there are also a number of detergents used in the process, such as:
- potassium hydroxide (KOH)
- sodium hydroxide (NaOH)
which are used to remove difficult stains.
And these detergents have been shown in research to present their own issues, such as the formation of acid rain, ecotoxicity, and in particular, eutrophication.
Eutrophication describes the process of algae formation. When there’s an increase of certain nutrients in the environment, some of this leaks into the water.
And when this happens, algae blooms use these nutrients to proliferate and, as they do so, produce large quantities of CO2, reducing the available oxygen for other organisms.
It also lowers the pH levels of the water, increasing acidity, which affects the growth of other aquatic organisms, leading to wide-scale effects across the ecosystem.
The nutrients which cause this damage are actually ammonia, nitrogen, and phosphorus species (aka forms).
But detergents containing components of these compounds, such as those we’ve listed above, can break down in the environment, leading to varying levels of eutrophication and marine toxicity.
Is Dry Cleaning More Eco-Friendly Than Washing?
In short, no – laundry or wet washing isn’t particularly more eco-friendly than dry cleaning.
Both have their own issues, so it would be hard to say which is worse than the other.
As we mentioned, water is one of the worst concerns for laundry washing.
For instance, it’s been estimated in studies that globally, 20 trillion liters of water and 100 TWh of electricity go to laundering each year.
Though PERC is not a component of laundry washing, there are still detergents used that have similar, if not greater, effects than dry cleaning in terms of eutrophication and other marine impacts.
And energy expenditure can be just as taxing when we account for the fact that laundering also requires a separate drying process.
These machines, i.e., tumble dryers, use a considerable amount of energy.
In fact, estimates cite that 5.8% of all residential electricity consumption is from dryers, that’s 66 billion kWh annually.
And, of course, when we’re talking about this kind of energy creation, electricity is often generated from fossil fuels, which leaves a considerable carbon footprint.
The EPA notes that the above electricity expenditure is equivalent to over 28 million metric tons of CO2, or the same as powering seven coal power plants for a year.
Are There Eco-Friendly Alternatives to Dry Cleaning?
There are several alternatives to dry cleaning, each with its own pros and cons to consider:
1. Professional Wet Cleaning Services
Wet cleaning is the same as laundering, except it’s a service provided by a commercial clothes cleaner.
They use specialized computerized equipment to deliver optimum cleaning but without the use of PERC.
Moreover, unlike dry cleaning, where detergents used have to be compatible with the machine itself, wet cleaning services can employ biodegradable detergents, which reduces the risk of damage to marine environments.
And while wet cleaning services do have the same issues we mentioned above, interestingly, energy consumption does appear to be between 19 and 40% lower compared to dry cleaning services, according to research.
This may be due to the choice of machines used, as energy-efficient laundering machines are on the rise, but it’s likely also because the clothing could be air-dried overnight, which reduced the need for tumble dryers.
But as expected, water consumption went up 37% after making the switch from dry to wet cleaning, so the overall environmental result is debatable.
2. Washing Clothes by Hand
If we take machines out of the picture altogether, another option is hand washing.
This is where the washing is carried out manually, and clothing is air-dried accordingly.
This method of cleaning is far less environmentally taxing than wet or dry cleaning.
In fact, studies show on average, water use was lower, and energy expenditure was near 0 for hand washing.
There’s no risk of PERC exposure, but detergent use was variable.
We also have to consider the labor and time required for hand washing, which may not be feasible for everyone.
3. Steam Cleaning
Steam cleaning is not a means of fully washing or laundering clothes but rather extends their use so that they don’t have to be cleaned as often.
Steam cleaning uses pressurized water vapor to sanitize and deodorize clothes at a much quicker rate than dry or wet cleaning.
And this likely means that energy and water use will be considerably lower, but eventually, some form of cleaning would have to be used as soiling accumulates.
However, research does point out that only 7.5% of laundered clothes are actually heavily soiled when washed, so the use of steam cleaning might be able to extend clothing use longer than thought.
Moreover, since it doesn’t require detergents or PERC, there’s less environmental risk.
4. Liquid CO2 Cleaning
This method of cleaning has similar applications to dry cleaning. It’s designed to be used without water, substituting PERC for liquid CO2.
It’s been shown in research to outperform many chemical solvents in cleaning and doesn’t need the same high temperatures to dry clothes as dry or wet cleaning.
Moreover, since CO2 is readily available and doesn’t need to be produced from manufacturing processes, it could be an effective alternative to mitigate most of the environmental and health-related issues of other cleaning methods.
However, the issue is that the technology, whilst available, requires a substantial upfront payment, which might not be viable for many, at least in its present state.