DOI: http://dx.doi.org/10.7554/eLife.00966.001 As air flows into our lungs, the lining of the nasal cavity, the throat and the rest of the respiratory tract prevents microbes, bacteria, dust and other small particles from entering the lungs.
Bioaerosols (microbes, dust and endotoxins) and volatile organic compounds (VOCs) were determined in the working air of a drum composting plant treating source-separated catering waste.
Persistent levels of methane in the atmosphere on Mars could have been a sign that living microbes lurked deep beneath the rock and dust, but the absence of the gas will deflate hopes that they are there to be found.
The particles (and microbes) in these dust clouds then settle into the lungs of children in Florida and on Caribbean islands in which asthma rates have risen some twentyfold in the past several decades.
Does our path to good health lie in breathing microbe-rich dust and regaining the fecal content of our ancestors (while avoiding, of course, the disabling chronic illness that often went along)?
The idea that excessive cleaning has created "sterile" homes is implausible: microbes are rapidly replaced by organisms shed from us, our pets, raw foods and dust.
