Sophiem, No, it's not safe. Their feces carry organisms that are harmful to humans.

Cats go to toilet in our gardens and we eat the potatoes. The soil is full of various organisms anyway and most people peel or, at least, scrub root vegetables before eating them. These organisms do not enter the vegetable but would only be present on the outside.

Er thanks to both of you! I am confused now though!

Presumably the potatoes are going to be washed, peeled/scrubbed and cooked at a high temperature. I can't see a problem, not much could survive that treatment.

I thought that people use organic fertilizers because they don't want the chemicals vegetables absorb from the non-organics. There are warnings on the bags of cat litter that "used litter not recomended for garden use"- Tidy Cat.