After nearly 14 years of composting all of my family's and visitors' humanure on the same spot about 50 feet from my garden, and using all of the finished compost to grow the food in our single garden, I analyzed my garden soil, my yard soil (for comparison), and my compost, each for fertility and pH, using LaMotte test kits from the local university.1 I also sent samples of my feces to a local hospital lab to be analyzed for indicator parasitic ova or worms.
The humanure compost proved to be adequate in nitrogen (N), and rich in phosphorus (P), and potassium (K), and higher than either the garden or the yard soil in these constituents as well as in various beneficial minerals. The pH of the compost was 7.4 (slightly alkaline), and no lime or wood ashes had been added during the composting process. This is one reason why I don't recommend adding lime (which raises the pH) to a compost pile. A finished compost would ideally have a pH around, or slightly above, 7 (neutral).
The garden soil was slightly lower in nutrients (N, P, K) than the compost, and the pH was also slightly lower at 7.2. I had added lime and wood ashes to my garden soil over the years, which may explain why it was slightly alkaline. The garden soil, however, was still significantly higher in nutrients and pH than the yard soil (pH of 6.2), which remained generally poor.
My stool sample was free of pathogenic ova or parasites. I used my own stool for analysis purposes because I had been exposed to the compost system and the garden soil longer than anyone else in my family by a number of years. I had freely handled the compost, with bare hands, year after year, with no reservations (my garden is mostly hand-worked). I repeated the stool analysis a year later (after 15 years of exposure) again with negative results (no ova or parasites observed). Hundreds of people had used my compost toilet over the years, prior to these tests.
These results indicate that humanure compost is a good soil builder, and that
no intestinal parasites were transmitted from the compost to the compost handler.
This wasn't a laboratory experiment; it was a real life situation conducted
over a period of 15 years. The whole process, for me, has been quite successful.
Adequately aged, thermophilically composted humanure is a pleasant-smelling, hygienic material. It can be freely handled and used as mulch in a food garden. The author's asparagus bed is shown here getting its 17th annual spring mulching.
Another five years have passed since I did those analyses, and over the entire 20 year period, all of the humanure compost my family has produced has been used in our food garden (see color photos following this chapter). We have raised a lot of food with that compost, and a crop of lovely and healthy children with that food.
One person commented that the Ova & Parasite lab analyses I had done at the local hospital were pointless. They didn't prove anything, or so the contention went, because there may not have been any contamination by intestinal parasites in the compost to begin with. If, after fifteen years and literally hundreds of users, no contaminants made their way into my compost, then why do people worry about them so much? Perhaps this proves that the fears are grossly overblown. The point is that my compost has not created any health problems for me or my family, and that's a very important point, one that the fecophobes should take note of.
Source: The Humanure Handbook. Jenkins Publishing,
PO Box 607, Grove City, PA 16127. To order, phone: 1-800-639-4099.