Peanuts.
We have years of data from the space stations.
This is an equipment test flight with four passengers.
Do they analyze bowl movements too?
Stool samples?
Then the broken crapper will spoil all those tests!
The international space station is well inside of the earth’s magnetosphere, which shields the earth and it’s atmosphere, from allot of solar and stellar radiation. That protection diminishes completely for the moon for 75% of it’s orbit (21 out of 28 days) around the earth. Yes, humans will experience greater radiation orbiting around, or on the surface of, the moon than what they experience at the international space station.