Humanure

2023-01-09

2 minute read

compost

My current waste disposal system is a septic, but it’s never made sense to me to pay someone to come and drain a tank of stuff I could be composting. So, I’ve been investigating whether humanure would be a good system for me.

People have a natural dislike and distrust of using humanure, but I’ve never seen actual reasons to be leery of it besides “it’s poopy”, which I don’t find impressive.

My main concerns:

Pathogens
Toxins
Antibiotic resistant microbes

In general, I’d like to not bring in any inputs like commercial fertilizers. The various critters I’ll be raising on my land should help. But I’m pulling my weight, too, and I have expectations of my visitors and guests to do the same.

Water disposal of waste is a fairly new invention. Dry disposal of waste is still practiced in many places. Despite our modern squeamishness towards it, it’s still a safe practice. The use of humanure for agriculture has been judged safe, with moderate amount of heavy metal content if combined with potash (1) and does improve the fertility of depleted soil.

Of some concern was the possibility of medications passed through urine into the ground. This is bypassed by simply not taking medications, and will be my methodology. Should a visitor come in who is on a serious medication, they will have to pack out their biohazard waste. Just kidding… right?

However, there does seem to be some need for care, as several studies on current practices show signs of fecal borne diseases and parasites being spread by humanure use.(2),(3),(4)

Even so, there’s many case studies of urine diverting dry toilets (composting toilets which mechanically separate urine from fecal matter) which don’t have these associations, so we might consider that the use of night soil in the previous examples were using subpar methods.

One study (5) in Ethiopia gives a great overview on the proper use of these UDDT’s which includes their proper use. The potential for these UDDT’s to contribute to health risks has been investigated, but the researchers were unable to come to a conclusion (6). Another study indicated that confusion over the purpose of handwashing may play a role in the high rate of intestinal parasites over any impact the UDDT could have alone (7).

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