It's been estimated that the average home collects 40 pounds of dust every year. Where it comes from, what it contains, and the health risks associate with it may be a great reason to say...get get the air ducts in your home cleaned. But let's be clear, this isn't that.
This is lint from your clean clothes. The danger isn't how many allergy-inducing particulates or dust mites it contains. The concern is fire. Hitting the start button on your dryer probably feels like the safest, labor-saving thing you might do during your day. And it should be. And it can be! We'd be happy to help you get it that way.