Crazy maps reveal colonies of bacteria and chemicals all over the human body
Our largest and most exposed organ — our skin — is covered in and composed of not just human skin cells but also about a trillion bacteria (and even more viruses) along with molecules from chemicals we come into contact with every day.
Researchers just mapped the “chemical topography” of human skin in order to figure out what exactly is living and settling on there and how those skin cells, bacteria, and chemicals interact. We have different types of bacterial communities all over and inside our bodies, and while scientists have previously created maps of the skin microbiome, this was the first map to look at what these bacteria are doing and how they interact with the chemicals we’re exposed to in day-to-day life.
To create these maps, researchers asked a man and a woman (person 1 and person 2, respectively) to skip bathing, shampooing, moisturizing, and using almost all cosmetics for three days (the woman did use deodorant during that time). After three days, they took samples from 400 individual spots on each person’s body so they could run two different types of analyses to see what they found.
It’s important to note that these maps are only representative of two people — there is likely a huge variety of bacterial and chemical diversity among humans. Part of the goal here was to show that these 3D topographical maps could be created, which they did successfully, but they also found all kinds of other interesting things. One intriguing finding? The cosmetic products that touch our skin, like soap and shampoo, seem to leave chemical residue that stays on skin for days, weeks, or longer.