Children who are not able to rinse or spit should not be using toothpaste containing flouride. There are children's toothpaste available at supermarkets without any flouride added. Water flouridation is extremely controversial, as flouride is a known toxin. Dentists will tell you that it prevents tooth decay. Personally, I think this is only true when the flouride is applied topically. But when there is the danger of flouride being ingested (as in a toddler unable to spit out properly and therefore swallowing some of it), then it is not safe and should not be used.