It’s no secret that microplastics have already infiltrated our lives, and nowhere is this more present than in our own homes. Microplastics — and even tinier nanoplastics — stem from daily tasks like cooking and cleaning. Now, research is pointing to the previously unexplored impact of dishwashing on microplastic pollution.
A new study published in American Chemical Society ES&T Water has revealed that washing plastic containers and utensils in a dishwasher releases plastic particles, which proceed to enter wastewater. Although the study confirmed that the release of microplastics in dishwashers is relatively low compared to other sources of microplastic pollution, it could still impose cumulative consequences on the environment.
Microplastics vs. Nanoplastics
Emerging research on microplastics has demonstrated that they are essentially ubiquitous, existing in many of the products we use. Food preparation and packaging products are a particular area of concern. Studies have identified plastic cutting boards and disposable food-grade nylon bags, for example, as significant sources of microplastics. Even tea and coffee bags release microplastics when immersed in hot water.
While microplastics range from 5 millimeters (the size of a pencil eraser) to 1 nanometer, nanoplastics are smaller than one millionth of a meter (one micrometer). The smaller size of nanoplastics has scientists concerned, as it allows them to be absorbed by cells; one 2022 study found that nanoplastics can cause damage to human liver and lung cells.
Read More: Lasers Could Help Detect Nano- and Microplastics in Bodily Fluids
Microplastics From Dishwashing
With the new study, attention has shifted to dishwashers as another source of microplastic and nanoplastic pollution.
The study found that a single dishwasher cycle with a full load of common plastic items could release about 920,000 microplastic and nanoplastic particles into wastewater. This ultimately adds up to 33 million particles per household per year globally.
Although this number may sound intimidating, this plastic mass only equates to “about 6 milligrams per person per year, or about a quarter of the weight of a grain of rice,” according to a statement on the study.
“Despite the high number of particles released, the total mass released from plastic containers is low and is minor compared to other known sources of plastic pollution,’’ said author Elvis Okoffo, a research fellow at the University of Queensland.
Regardless, microplastics from dishwashers eventually end up in a wastewater treatment plant, which can remove more than 90 percent of microplastics from wastewater. However, the filters here are not perfect, as millions of microplastics can still slip through and adversely affect ecosystems.
Solutions for Household Appliances
Even though dishwashers may not be the biggest concern in terms of microplastic pollution, the fact that millions of households regularly use them amplifies the environmental risks. However, strategies to limit microplastic pollution from dishwashing and other household tasks have been suggested.
Filters fitted on dishwashers to catch microplastics before they enter wastewater could be a possibility in the future. Similar filters already exist for washing machines, another appliance that sheds microplastics — particularly, microfibers from laundry that includes polyester and acrylic material.
“Removing this pollutant before it can enter the environment is better than implementing costly measures after the pollutant has already been released,” said Okoffo in a statement. “Small changes, when multiplied across millions of households, can help reduce the global burden of plastic pollution.’’
Read More: Wood vs. Plastic Cutting Boards: Which One Is Cleaner and Healthier?
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
American Chemical Society ES&T Water. Release of Micro- and Nanosized Particles from Plastic Articles during Mechanical Dishwashing
Environment International. A systematic review of microplastics emissions in kitchens: Understanding the links with diseases in daily life
American Chemical Society. Nanoplastics can disrupt human liver, lung cells’ processes in lab experiments
Springer. Contribution of household dishwashing to microplastic pollution
National Park Service. Reducing Laundry Microfibers
Jack Knudson is an assistant editor at Discover with a strong interest in environmental science and history. Before joining Discover in 2023, he studied journalism at the Scripps College of Communication at Ohio University and previously interned at Recycling Today magazine.
