More than 700,000 microscopic fibers can be dislodged in wastewater during each use of a household washing machine, and much of it can overcome scrubbing and end up in the wild.
A study conducted by the University of Plymouth examined the mass, abundance and size of fibers present in waste effluent after synthetic fabric washes at normal temperatures of 30 and 40 degrees Celsius.
It was found that hundreds of thousands of tiny synthetic particles could be released in each wash, confirming that laundry is an important source of microscopic fibers within the aquatic environment.
The research, published in the Marine Pollution Bulletin, was led by PhD student Imogen Napper in conjunction with Professor Richard Thompson, who is an international expert on microplastics and marine debris having worked in this field for more than 20 years.
"The amount of microplastics in the environment is expected to increase in the coming decades, and there is concern that it could have harmful effects if ingested. But while the release of minute fibers as a result of washing textiles has been Widely suggested as a potential source, there has been little quantitative research on its relevant importance, or on the factors that may influence such discharges, "the authors explain to put their research into context.
For the study, a series of polyester, acrylic and polyester-cotton items were washed at 30 ° C and 40 ° C using various combinations of detergent and softener. Fibers were then extracted from the waste effluent and examined using an electron microscope to determine typical size and any differences in mass and abundance between treatments.
The research found that washing an average 6-kilogram load of laundry could release an estimated 137,951 fibers of cotton-polyester blend fabric, 496,030 fibers of polyester and 728,789 of acrylic. The cotton / polyester blend yielded fewer fibers than the other two types of fabric, regardless of the different treatments, and the addition of bio-detergents or conditioners tended to release more fibers.