When spices have one ingredient, they’re fine. Blended spices need to be looked at their ingredients.
For example, paprika, where the ingredients are just Paprika, there’s no need to ask.
Zaatar, however, has multiple ingredients and at times can contain wheat flour.
Aaron Abadi 
michael aryeh 
Josh Wachtel
When spices have one ingredient, they’re fine. Blended spices need to be looked at their ingredients.
For example, paprika, where the ingredients are just Paprika, there’s no need to ask.
Zaatar, however, has multiple ingredients and at times can contain wheat flour.