Planetary Pros: No, it’s not a joke!
Radiation shielding is all about creating barriers and scientists are investigating ways to create barriers within the space craft that use waste from astronauts such as wee and poo, as well as water, and even food supplies to shield against radiation.
The benefits are that a water supply and food will already be factored into the payload, and there’s no need to take any waste!
Cosmic Cons: Aside from concerns about the smell, trials have shown that these water walls aren’t quite as effective in orbit as they are on the ground, and they aren’t effective at all against cosmic rays – the high-powered radiation that comes from other galaxies.