Bee pollen allergy

Can anyone explain what is bee pollen allergy?
Just there are few foods I would like to buy but it is said "not suitable for people with bee pollen allergy" so I want to check out before I can buy it because I never heard of it.
I am allergic to bee sting but can eat honey. So I am not sure about my three children who got multi-food allergies (egg, milk, peanuts, tree nuts, kiwifruit and fish) as well as one of them got severe grass pollen allergy (swelling and hives - non-rhinitis type)
thanks
Soph