In my last post I mentioned that my coworker Don told me that Vietnam no longer uses human manure. But that got me thinking: what's wrong with human manure? It can't be that different from other animals' poo. I brought this up with Don: do we just not use human manure on principle, because it just seems grosser than cow manure? Does the idea just hit too close to home, kind of like the fact that we eat cow muscle but not cat muscle: the idea of eating cat muscle hits too close to home?
He assured me that human poo does indeed smell worse than other animals' poo.
Skeptical, I looked it up.
Some background: through time and in different areas, human poo has been called "night soil" because it has been collected from homes at night in what are called "honey buckets." Then it is disposed of in various ways. Sometimes it is used as fertilizer.
After doing a bit of research, I wrote this email to Don:
Don-
I read about night soil and honey buckets. Gross and full of
pathogens. But it looks like there is a good process now for making
“humanure,” which, when treated properly, does not stink. It has to heat
and sit for 1-2 years though before it can be used. You can read about the
process here:
http://en.wikipedia.org/wiki/Humanure
Also,
looks like the diet is what makes human manure so much more stinky than other
animals’. Look at what Wikipedia says:
“Manures with a
particularly unpleasant odor (such as human sewage or slurry from intensive pig
farming) is usually knifed (injected) directly into the soil to reduce release
of the odor. Manure from pigs and cattle is usually spread on fields using a
manure spreader. Due to the relatively lower level of proteins in vegetable
matter, herbivore manure has a milder smell than the dung of carnivores or
omnivores – for example, elephant dung is practically odorless. However,
herbivore slurry which has undergone anaerobic fermentation may develop more
unpleasant odors, and this can be a problem in some agricultural
regions.”
So I guess that says something about me, since I am a
vegetarian. :) I have heard it said of someone, “He thinks his poo
doesn’t stink.” Which of course is meant to say that he thinks he is above
everyone else. But maybe his poo really DOESN’T stink, and therefore he IS
above everyone else!
It’s all very interesting to me.
And to think I almost worked from home today! It was worth going because of the above new treasures of knowledge I gained.
Please thankfully note that I have not included a picture with this post, though I was sorely tempted.