Did you know that the average house collects a shocking 40 pounds of dust per year? Dust is more than just the thin layer of dirt you see accumulating on your dining room table. Common household dust contains a variety of particles, many of them microscopic, including airborne bacteria that can actually make us sick. Scientists have found one surprising, yet not so unexpected way to kick those bacteria to the curb: expose them to sunshine!
In a 2018 study published in the medical journal Microbiome, researchers at the University of Oregon created eleven identical climate-controlled miniature rooms that resembled real buildings. Each of these miniature structures had walls and windows, just like ordinary buildings would. Researchers then collected dust from real homes with real people and placed the dust samples inside each of the eleven rooms.
To test their theory, they placed one of three specialized window glazes on the tiny windows, each one allowing either visible, ultraviolet (UV), or no light at all to enter. And for the next 90 days, they exposed the miniature structures to sunshine. Some of them were in total darkness, while others received either full-spectrum light or UV light only.
After 90 days, they meticulously collected the dust and sampled the bacteria in it. Not surprisingly, they discovered that the household dust exposed to ordinary daylight contained 50% fewer bacteria when compared to the dust bunnies who had lived in complete darkness for 90 days.
It seems as though great-grandma was right: opening the blinds and letting the sunshine in keeps us healthy and reduces the number of opportunistic bacteria lying around.
So, here’s to appreciating sunshine even more!