Unfortunately not urban legends, no. Back when my mum&dad lived in Copenhagen, there was a sicko in the local supermarket that would put razor blades in apples :/
Oh, and the maniac that would put pipebombs in sandboxes, disguised as toys... and in phone booths. So, all phone booth doors were removed in the whole of Copenhagen, and stored at some central place. When the bomb manic was finally caught, it turned out that there were different kinds of phone boxes (with incompatible doors...) and that nobody had kept track of which doors were taken from which booths...