A compost toilet is an aerobic environment composed largely of sawdust, human waste and sometimes earth that is decomposed by bacteria and fungi. Properly managed, it's perfectly safe.

https://en.wikipedia.org/wiki/Composting_toilet

You still don't necessarily want to/can't use composted human waste for growing food for human consumption, because many jurisdictions regulate their application in different areas of agriculture.

e.g.:

Virginia: "All materials removed from a composting privy shall be buried," and "compost material shall not be placed in vegetable gardens or on the ground surface.[0]

Rhode Island: "Solids produced by alternative toilets may be buried on site," while, "residuals shall not be applied to food crops.[1]

I'm all for doing it regardless, as it seems more sustainable than traditional sewage treatment!

[0]https://en.wikipedia.org/wiki/Composting_toilet#cite_note-26

[1]https://en.wikipedia.org/wiki/Composting_toilet#cite_note-25

Blood and Waste both carry similar risk and hopefully anyone using a composting toilet are aware of the needs to properly bake off organisms.