Shamelessly stolen from Dr. Isis
Yes, you read the title correctly. As I’ve mentioned before, I’m involved with the Human Microbiome Project, which examines how the microbes that live on and in us affect human health and disease. One of the things we do is look at human gut communities. In most cases, examining the bacteria growing on the side of gastrointestinal tract is…difficult. Think the Mother of All Protological Exams. So we use feces as a proxy of what lives in your gut. And since you were going just flush that stuff anyway, mind if we….
Well, you get the idea. Now you might think that collecting poop is straightforward. You would be wrong. We actually have to be quite rigorous about poop collection. For example, we don’t some stools sitting around at room temperature and in the presence of oxygen, which allows some bacteria to grow while others can’t (many will die in the presence of oxygen).
This becomes even more complicated, since there are 300 people being sampled. Most people don’t poop on command, and following them around with buckets isn’t really practical–not to mention, incredibly creepy. Fortunately, we have detailed instructions for our volunteers.
So here’s how to take an NIH-sanctioned study-acceptable poop:
Raise the toilet seat. Place the stool collection frame on the back of the toilet bowl. All four corners of the collection frame should be supported by the toilet bowl.
Place collection bowl in frame (if you don’t, it kinda defeats the purpose of the whole exercise):
Place toilet seat down (do people really crap without doing this?):
DON’T PEE IN THE BUCKET! (That’s actually in the instructions, although not put as elegantly). Not only will the urine alter the microbial community of your poop, but it’s really gross too. Thankfully, there’s an emergency backup container (poop collection is like the Apollo missions, but without rocketships. And with lots of poop).
Remove and seal tightly! Like so:
Place the container in a Ziploc bag–cuz it’s a bucket of shit:
Now we have to ship it–and we have to keep said poop cool, but not frozen (freezing can lyse cells). Using seven ice packs, completely surround the container with the packs, like so:
Then follow the shipping instructions.
All kidding aside, one of the key things the HMP will have accomplished–although it’s not very sexy science–is developing standard methods. Without this, we simply don’t know to what extent community differences are due to interesting biology versus methodological variability.
For this, and other methods, check out this website (the sample collection manual is available as a pdf here).
Ain’t science cool?