Genetically designed pestkiller might help, but if it were that easy some mosquito groups and malaria would be a thing of the past. Anyway don't some birds eat them ?
Have used them in the past and they do seem to work .. just a bit expensive if you have a large plot and apply them at recommended intervals.
Personally over the winter I have spread loads of seaweed everywhere, lets hope that keeps them at bay.
Hopefully the slug predators like frogs, toads, hedgehogs, badgers, birds etc
will also help to address the balance and keep numbers down.
I have a theory that slugs and snails are mostly driven by smell and can sniff out a plant that has be weakened by transplanting like a blood hound on the trail of a convict.
If a product can be produced that gives off a smell that slugs hate, then thats where the answer might be.
They seemed to sniff out my tomato plants easily, last year. Not put this year's ones out yet. Still seeing the odd frost, and rumours of snow in some of those northern and eastern climes.