Did you know that as babies crawls on the floor, they kick up dirt, bacteria, and other bio-junk, and breathe them. To further study this, Purdue Researchers built a robotic crawling baby. It was used to crawl on carpet samples removed from homes. They found that infants may be inhaling 4 times as much bio-bits as what an adult would walking across the same floor.
As the researchers explain, they:
used state-of-the-art aerosol instrumentation to track the biological particles floating in the air around the infant in real-time, second by second. The instrument uses lasers to cause biological material to fluoresce. Most bacterial cells, fungal spores, and pollen particles are fluorescent, so they can be reliably distinguished from non-biological material in the air
More information is available here.