Dear All,
Actually, at least for the European area, a several-page table of (permitted ingredient) vs (country) for many common items/industries was presented by FAO about 20yrs ago but rarely seen these days probably due to the lack of maintenance. It was in considerable demand at that time, particularly by the labelling community.
Thks Arya for this fascinating link. It's a noble effort indeed but it sadly failed both the 2 tests i applied to it -
1. Sodium tripolyphosphate (aka STPP) not listed (at least by this name) under S,T or P, probably the most well-known ingredient in the seafood industry

.
2. No mention of vegetable-type allergens in the specific category, eg celery which is equally famous as I hv learnt from this forum. [added, slight correction, it does hv a brilliant article on mustard which I did not know about

, the words revulsive and cataplasm certainly sound frightening and they are an
intended application!]
Regardless, it's still a gold mine of data, just illustrates the nature of the data handling problem. Comprehensive lists of E-products with their allowed tolerances do exist elsewhere of course. Similarly GRAS and Food Codex compilations but none of these attempt to do a country-by-country breakdown AFAIK. Merck Index and others are also frequently in use in the general situation IMEX.
However, I do agree a database of the kind discussed would be of immense value, just need financing from some rich philanthropist, Bill Gates perhaps in exchange for Honorary Fellow of IFSQN.
Rgds / Charles.C