I know someone who still has 3 bottles of Derris in his or her shed
Seriously though, I believe the risks to pets and wildlife were very overstated and without foundation in actual evidence. A theory that became fact. However, incorrect use by farmers has been causing pollution of water so there is a basis to ban it.
I've been using Growing Success and Neudorff Sluggo for years - both are ferrous phosphate based and I find them more effective than metaldehyde pellets. A bit more expensive - but used correctly a pack will be more than enough for a year.
I think the blue colour is used in some fertilisers (like Miracle Gro) as a warning. Certainly the pellets contain a bittering agent to stop pets and mammals eating them