Comment by celticninja

In small quantities. As somebody already pointed, your body likes to keep its water inside it, it also doesn't like when stuff carries large quantities of unmixed digestive fluids from one part of your body to another.

They are probably quite harmful if large pieces get eaten in non-small quantities. Or powder in large quantities that are not previously mixed with a liquid. But I don't know of anybody that tested that.

You can also ingest up to one cup of gasoline.