I have no idea and have never had the courage to try one. Most of the ones I see in shops have syrup added to them.
A proper chai tea has a mixture of spices added to black (formosa) tea. Depending on what part of India you are from these can range from one spice - my friend used cardomom, to a blend of 8-10 spices including cinnamin, black pepper, orange peel etc etc.
So I hate to think what is in those syrups.