One household chore is sneakily polluting the environment — study

You can't see most of them, but microplastics have permeated the environment. A major source of the tiny plastic molecules that drift through the oceans, soil, and sky? Your clothes.

According to new research, what you wear, and how you wash your clothing, affects the number of synthetic microfibers you are releasing into the environment.

A massive amount of microfibers from laundry are released into the environment each year, scientists reported Wednesday in the journal PLOS One. Microplastic pollution from washing clothes has not been accounted for in previous research, the study authors say.

In the first global estimate of its kind, the team studied the volume of synthetic microfibers released by washing apparel between the years 1950 and 2016, finding that similar amounts of plastic enter bodies of water and land every year.

As access to wastewater treatment increases across the globe, the authors argue we can expect increasing amounts of microfibers to reach land, especially cropland. Previous research suggests microplastics interfere with basic soil properties, potentially messing with the function of soil ecosystems.

To understand the severity of microplastics from laundry, researchers dug into data on clothing production, use, and washing. They estimated that 5.6 megatons of synthetic fibers from laundry were released between 1950 and 2016. Half of the total amount appeared during the last decade.

Jenna Gavigan, a researcher at the University of California, Santa Barbara, led the new study. The goal was "to create a baseline estimate of microfiber emissions," Gavigan tells Inverse, "so that we can understand the scale of the issue across the globe."

Gavigan and her colleagues argue that it should be a priority for individuals to prevent or reduce microfiber pollution before it enters the sewer system.

Stopping pollution at the source — Solving something as global as plastic pollution will involve changes to more than individual behavior. But anyone who loads a washing machine can do something to curb the amount of plastic that enters the environment.

One actionable step: reduce consumption. You can also use a microfiber trapping bag or lint filter to capture microfibers during the washing process, the study authors say.

"If readers want to reduce their microfiber emissions from apparel they can buy higher quality, low-shed garments and use microfiber trapping technologies such as microfiber filters on washing machines," Gavigan says.

The study didn't account for reused, donated, or recycled clothing. But it's unlikely that including clothes that get thrifted would improve the outlook, the authors write: "Since there are large markets for secondhand clothing, especially in lower-income countries, taking this factor into account would likely increase the stock of in-use apparel and therefore increase emissions."

Up the production chain, it's likely that clothing and fiber production releases microfibers, too. At that level, Gavigan's team suggests designers should consider creating clothes, textiles, and fibers to be less prone to shedding during washing.

Ultimately, the paper calls for stronger steps to reduce plastic pollution that enters the water and soil, noting that in some countries, lint filters on washing machines come standard.

"While more research on the interactions between microfibers and the environment is urgently needed, especially in terrestrial ecosystems, this should not stop us from enacting mitigation measures now," the team writes.

Abstract: Synthetic microfibers are found virtually everywhere in the environment, but emission pathways and quantities are poorly understood. By connecting regionalized global datasets on apparel production, use, and washing with emission and retention rates during washing, wastewater treatment, and sludge management, we estimate that 5.6 Mt of synthetic microfibers were emitted from apparel washing between 1950 and 2016. Half of this amount was emitted during the last decade, with a compound annual growth rate of 12.9%. Waterbodies received 2.9 Mt, while combined emissions to terrestrial environments (1.9 Mt) and landfill (0.6 Mt) were almost as large and are growing. Annual emissions to terrestrial environments (141.9 kt yr-1) and landfill (34.6 kt yr-1) combined are now exceeding those to waterbodies (167.2 kt yr-1). Improving access to wastewater treatment is expected to further shift synthetic microfiber emissions from waterbodies to terrestrial environments. Preventing emissions at the source would therefore be a more effective mitigation measure.