How China's Pollution Sniffers Work

China's Pollution Sniffers: Author's Note

Senior Writer
HowStuffWorks 2009
Josh Clark, Senior Writer

There has always been one aspect of the pollution sniffers in Guangdong province that I've never been able to get to the bottom of -- why use humans? I wondered about it when I wrote the article, as well as when I created a "Stuff You Should Know" podcast episode on it, and I wonder about it still now. All of the attendant damage that comes with purposefully exposing humans to air pollution -- and not only that, but getting them to take long deep breaths of it as their jobs -- seems at least dangerous if not totally unnecessary. In the fourth section, I chronicled a number of mechanical sensors that could do just as well and actually much better than human pollution detectors. So, why use people?

This was my first article for It was a test article, actually, the one that got me hired, so I have a real affinity for this one. Researching for it also provided my first introduction to the fascinating fact that science doesn't know how we experience the sensation of smell. Getting acquainted with the theories of smell that I talk about in this article also exposed me to how much we have left to learn.


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