Well that might be due to the fact that not all people have allergies. Therefore they aren't affected by allergens like others. For instance i am affected my many allergens, whereas my elder sister is not affected by allergens at all. As you see i used the word 'allergens' several times. Most of the time the word 'allergens' just doesn't come up in a majority of conversations.

it procted um....... germs and allergens !!!!!!!!!!!! it procted um....... germs and allergens !!!!!!!!!!!!

Common food allergens include nuts, fish, and milk.

Air dusters don't quite remove allergens. They are mostly used to blow away dust and allergens off of a surface, like electronics. The allergens are still in the environment. An air filter would work better.

Alcohol