Question:
i have read something about musk..but i am wondering then,if every perfume that has musk is dangerous then many perfumes would have stopped from production.......are there any specific brands that they were acused of using dangerous ingredients?

Answer:
think about all the synthetic ingredients in perfumes (even expensive niche perfumes). thousands of compounds, most of which aren't regulated by the FDA (to my knowledge). do the math. even some of the natural ingredients are dangerous when used topically in any robust quantity.
luckily, they are used in very small amounts. and it's probably not much worse than what's in the air we breathe (at least in (sub)urbia). still, i wouldn't take a bath in any of my favorite scents. luckily, i have skin that is very efficient for a scent lover: things last forever on me, yet also project well -- a seeming contradiction. i definitely would be careful about emulating certain BN-ers who claim to spray 50 sprays per application. (though i don't know where the danger threshold would lie. 500 squirts? 5000? they'll all vary considerably anyway...)

Answer:
Lime/Lemon oils are dangerous in high concentrations.
Lavender " ".
Sandalwood " ".
Tea Tree " ".
Basically, anything that is a natural astringent is dangerous in high concentrations. By dangerous I mean that you may experience itching, redness, or swelling. If you try on a cologne and have an adverse reaction, your best bet is to not buy that cologne, though I don't know of a specific list of hyper allergenic fragraces.
- Rich