As I hinted at above, under the impending EU REACH regulations, Enamel paints may well disappear forever in Europe. From what I've gleaned about it at work, REACH is a doubly pronged approach to environmental protection, it doesn't just look at the potential environmental damage chemicals may cause, it looks at whether those chemicals even need to be used at all ie, if there is a more environmentaly friendly alternative to a potentially damaging substance, even if more expensive, then the regulations will force you down that route.
Hence, bye-bye enamels, hello acrylics!