Dear Minou2 et al,
A very good question. Actually, except for ever more complex European Common Market labeling laws, to my knowledge most all of the 'rules' of what is allowed and what isn't are dictated by IFRA (International Fragrance Association), which is a self-governing body. Since most (or all) small niche houses are not members of IFRA, our usage (or levels of usage) of IFRA restricted substances is on our own shoulders. For instance, I have no one looking over my compounding ready to penalize me for using a ton of oakmoss or orris root, or whatever else I choose. IFRA studies such things as number of incidents of allergic reaction among the population in general and makes recommendations or rulings on "safe usage levels" as to percentage of the material allowed in the fragrance concentrate (if at all). We non-member niche perfumers try to follow those guidelines, too, as we have no statistics to dispute their findings. Having said that, many perfumers complain that IFRA has grown rabidly cautious in the last ten years or so and runs frightened because their idea is to self-govern to keep the law-makers from stepping in and perhaps exerting even tighter controls.
If I overstep the bounds of IFRA I'm taking a risk that I will run into allergic reactions among my customers. Since I have no statistics to follow, I have no idea how big that risk would be. Having said that, our parents consumed a lot of oakmoss, etc. in fragrances of old, so I suspect the risk is not really that high. In fact, I may come out with a fragrance using real oakmoss, perhaps judiciously mixed 50% with synthetic. This is actually a great advantage that niche perfumers have. We haven't taken an oath to uphold IFRA's rules so have the leeway to reintroduce more of the fragrance notes of yesteryear. One's own conscience as an artisan selling to the public is the only limit-setter, but it's a responsibility I for one take seriously. If you're interested, IFRA has a website. There is some information you can read without being a member. Go to:
http://www.ifraorg.org