It is, at least where I am coming from, well-known that raw human feces must not be used for fertilizing soil; However, composted (long enough / on high temperature) would break down the pathogens that are bad for humans.

See more on wikipedia about fertilization using human feces [1] and in general, applications of composting toilets [2].

[1]: https://en.wikipedia.org/wiki/Human_feces#Use_as_fertilizer

[2]: https://en.wikipedia.org/wiki/Composting_toilet#Applications