Hi Karen,
Thanks for your reply - it's really helpful. I guess I was more concerned about contaminating anything we grow with roundworm eggs and giving us humans worms! I trawled the internet and it seems that pig worms can infect humans and it can take up to 7 years for roundworm eggs to die in the soil. However, lots of people seem to use pigs as rotivators, so I'm really confused.... Is the risk so small most people don't worry? Or do people mainly use pigs as rotovators for vegetables not given to humans?
Thanks!