Knowledge
How do negative ions remove pollutants from the air?
Negative ions help freshen and purify the air by causing allergens such as pollen, mold spores, dust, and animal dander floating in the air (which have either a neutral or a positive charge) to be attracted to and stick to each other, forming 'clumps' (because opposite charges attract). These clumps of particles then become heavy enough so that gravity can pull them down to the floor, where they can be vacuumed up, rather than staying in suspension where they can be breathed in and cause allergic reactions.
As a result, they become too heavy to remain floating in the air, and fall harmlessly to the ground, where they cannot find their way into your respiratory tract.
At this point, even if they are inhaled before falling out of the air, these now larger particles are able to be intercepted by the "filters" of the upper respiratory tract, due to their increased size.