Try this test...........

[yogitunes]

The next time you change the filter on your central air (or even window units), spray 1/2 of the filter with furniture polish (lemon pledge or endust), then mark the date when you install this and re-check in 2 weeks and SEE your results....I couldn't believe how much dust was trapped on the "treated" side, and this was on cheap filters, beats paying the high price for the hepa ones, and this doesn't restrict air flow....I was amazed

Try it and see!!!

the lemon pledge adds a nice scent too!