Microfibers from polyester and nylon clothing might be doing more than polluting the planet, a new study claims. They could also inhibit the lung’s ability to repair airway tissue damage caused by Covid-19.
When researchers from Groningen University, the Netherlands Organization for Applied Scientific Research and the Plymouth Marine Laboratory exposed air sac organoids, grown using stem cells, to both nylon and polyester microfibers over two weeks, they found that the inhalable textiles interfered with the “miniature lungs’” ability to grow and develop. Since people are exposed to microfibers on a daily basis, they could present additional risks to those with developing lungs, such as children, the scientists warned.
“A virus damages lung tissue, and if you have to recover from that while your lungs are filled with fibers that impede this recovery, then you have another problem on top of Covid-19,” Barbro Melgert, an associate professor of pharmaceutical immunology at Groningen University and the study’s principal investigator, said in a statement.
The study, Melgert added, builds on research conducted by Fransien van Dijk and his colleagues on the impact of microplastics on lungs, the preliminary results of which were presented at the Plastic Health Summit in 2019. Polyester might be less disruptive to airway function than nylon, he found. While lung immune-system cells, called macrophages, mainly attack nylon microfibers, they leave polyester untouched for the most part.
“If we add nylon microfibers, we see that there is an enormous decrease in the growth of the mini lungs,” he said at the time. “When we add polyester, we see a minimal effect. This effect applies in particular to the development of the respiratory tract.” An average household generates about 20 kilograms of domestic dust a year, six of which consist of microplastics from synthetic clothing, carpets and furniture, he added.
Microplastics, once inhaled, can travel from the lungs of pregnant rats to their fetuses, according to a recent study by Phoebe Stapleton, an assistant professor at the Rutgers University-Ernest Mario School of Pharmacy who has been exposing animals to nanoplastics and then measuring the contents of both maternal and fetal tissues.
Nanoplastics, Stapleton said, were found in the pregnant rat’s lungs and heart and the fetus’s liver, lungs, heart, kidney and brain. “We need to get a better handle on human exposure overall initially,” she said in a statement. “We need to identify the chemicals in these nanoplastics.”
While environmentalists frequently sound the alarm about microplastics entering waterways through the laundering process—a single wash cycle can release 1 million microfibers, according to one report—wearing synthetic garments might slough off even greater quantities, researchers from the Institute for Polymers, Composites and Biomaterials of the National Research Council of Italy found last year.
A gram of polyester fabric might discharge up to 4,000 tiny fibers during a single conventional wash cycle, according to the study, yet that same material could shed a similar amount with just three hours of normal activity. Through the process of extrapolation, a single person could introduce nearly 300 million polyester microfibers per year to the environment by washing their clothes, and more than 900 million to the air by wearing them.
Indeed, research published last year in January by King’s College London scientists concluded that 92 percent of the microplastics abundant in London’s air are “fibrous microplastics” from abraded plastic textiles such as clothing, upholstery and carpets.
“We found some of the highest reported levels of microplastics in atmospheric dust,” Stephanie Wright, UKRI Rutherford Fellow in the School of Population Health & Environmental Sciences at King’s College London and lead author of the study, said at the time. “Fibers were the most abundant for the size range we looked at, mirroring the marine environment.”
One year later, scientists from the conservation nonprofit Ocean Wise would find that synthetic fibers make up approximately 92 percent of microplastic pollution found in near-surface seawater samples from across the Arctic Ocean, demonstrating the pervasiveness of the problem. Roughly 73 percent of those, they added, are polyester fibers consistent in size, shape and type to those shed by clothing and textiles during laundry.
“The striking conclusion here is that we now have strong evidence that homes in Europe and North America are directly polluting the Arctic with fibers from laundry via wastewater discharge,” Peter Ross, lead author of the study, special advisor to ocean conservation nonprofit Ocean Wise and adjunct professor of Earth, Atmospheric and Ocean Sciences at the University of British Columbia, told AFP. “Plastics are all around us, and while it would be grossly unfair to specifically point our finger at textiles as the only source of microplastics to the world’s oceans, we nonetheless see a strong footprint of polyester fibers that are likely to be largely derived from clothing,”