Green Junction - More Than Just Dust: The Microplastics Inside Our Homes
Indoor dust is described by the American Lung Association as “animal dander (including dead skin cells), dust mite matter and pollen.” It is interesting that the website also states “the American Lung Association has partnered with Swiffer to inform Americans about why they should be aware of dust in their homes.” SwifferTM sweepers are made of “specially coated synthetic fibers” or plastics. Products made up of synthetic fibers are known to release huge amounts of microscopic microplastics or microfibers.
Not surprisingly, a significant portion of indoor dust is plastic-based, in line with the numerous plastic products that are now common indoor items. According to a study of indoor dust published in 2022, 43% of microplastics in indoor dust originate from textile sources, such as carpet, clothes and blankets and are typically fiber-shaped. The other microplastics found in indoor dust are from numerous other plastic-based items, such as food containers, toys, furniture and paints.
Over the past year, I have had students collect dust samples from numerous indoor areas, from their homes to school buildings and labs. Microscope analyses have shown that microfibers were present in every sample. Some samples consisted of mostly microfibers even though they appeared like typical dust.
Plastic products include thousands of chemicals, many known to be toxic. A 2022 journal review article concluded that over 4000 tons of chemical additives from clothing are released into the air each year. An estimated 4.5–6440 micrograms/person of these additives are inhaled annually, the major route of exposure for humans. The other main route of exposure is through ingestion, estimated at 0.1–204 micrograms/person.
Many consumer products are made to be visually appealing, but information on the chemical content is not usually required. California and New York recently banned polyfluoroalkyl substances (PFAS) from apparel. These are used as waterproof and stainproof coatings. The bottom line is that healthy living requires low exposure to manufactured chemicals.