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Comment by senectus1 | Hacker News Reader

>Why such a high prevalence of roundworm and whipworm infections? The scientists speculate that the monks may have picked up the parasites when putting feces to work as a fertilizer, either by emptying their own latrines to manure crops, or by bringing in outside fertilizer contaminated by parasites in human or pig excrement. These hands-on practices were definitely used in Medieval and Roman times, just as they are today in parts of the world where other fertilizer options are scarce.

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Are there effective best-practices to sanitize human waste for manuring? I’ve skimmed the “Humanure Handbook” which suggests a combination of composting (aerobic decomposition) and time (about one year). Are quicker and more energy-intensive options, like charring, equally effective at sanitization without removing plant nutrition?

Best practices are that you really shouldn't. The potential value of human waste as an additive to growing food is (vastly) overwhelmed by the potential for pathogen spread, pharmaceutical pollution, the whole nine yards.

The longest-running project I'm aware of is https://en.wikipedia.org/wiki/Milorganite , which is similar to what you are asking, if you want to go for a deeper dive in the subject.

Thanks! Had never heard of Milorganite. My interest is purely one of curiosity, specifically how waste might be recycled in a Mars or Moon colony. The Chinese regenerative life support project Lunar Palace 1 claims 41% nitrogen recapture from solid waste, using a "bioreactor" i.e. flippable compost bin:

https://en.wikipedia.org/wiki/Yuegong-1

https://pubmed.ncbi.nlm.nih.gov/27912029/

It's unclear from the published results whether the crew ate food grown from this compost, or just measured the output's nitrogen content.

In Sweden "milorganite" like processes are as far as I know fairly common, but there is controversy around heavy metal and antibiotics content.

Municipal sewage is pretty commonly added to green waste compost products, in an industrial facility the temperature can be brought up pretty high quickly so I don't reckon the process is more time consuming than processing any the green waste itself

There are lots of places today in the 3rd world where you shouldn't eat uncooked food (salad).

No need to go to the 3rd world - there are plenty of places where eating raw lettuce is a bad idea. I went to a lecture once that went into detail on the lengths that the USA goes to to ensure our lettuce is safe to eat. The conclusion was that stuck with me was that the first time your lettuce leaves refrigeration is on the drive home, the speaker suggested that you bring a cooler in the trunk of your car to ensure proper cold chain management for leafy green purchases.

You can see some of the considerations in "Commodity Specific Food Safety Guidelines for the Lettuce and Leafy Greens Supply Chain" [1]

[1] https://www.fda.gov/files/food/published/Commodity-Specific-...

Here in India, the leafy greens are eaten very fresh, usually on the day of the harvest.

And, we don't usually buy greens from the supermarket where chikitshadhina even have a chance of maintainance, rather, we prefer to buy from Street side vendors.

What is "chikitshadhina"?

https://translate.google.com/?sl=auto&tl=en&text=cikits%20ad...

I don't understand what he meant though.

Indeed. Directly from the CDC[1]:

> Sometimes, raw fruits and vegetables contain harmful germs that can make you and your family sick, such as Salmonella, E. coli, and Listeria. CDC estimates that germs on fresh produce cause a large percentage of foodborne illnesses in the United States. The safest produce to eat is cooked; the next safest is washed.

How large of a percentage? About 45.9% of US food poisoning in the US is attributed to produce (of which 11.7% fruit-nuts, 34.2% vegetables), vs 47.8% to animals (of which 6.1% seafood, 13.8% dairy, 6.0% eggs, 22.0% meat-poultry)[2].

I suspect there's quite a bit of risk-compensating behavior at work here. We tend to hear a lot more about the dangers of raw meat, eggs and seafood than of raw vegetables, which probably makes people much more wary about them.

[2] https://wwwnc.cdc.gov/eid/article/19/3/11-1866-t1

[1] https://www.cdc.gov/foodsafety/communication/steps-healthy-f...

I work for John Deere. One of my coworkers went to learn about lettuce production in the real world. He was in the field wearing gloves and a hair net for safety, and they were taking heads of lettuce off the plant and putting them directly into the plastic bag it would be sold from in the store. Then he looked up: wild birds were flying all over, and like bird do dropping poop behind. His conclusion: wash your lettuce.

(none of the above speaks for the company of course)

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