We tend to think of air pollution as something outside -- smog, ozone, or haze hanging in the air, especially in summer. But the truth is, the air inside homes, offices, and other buildings can be more polluted than the air outside. The air inside your home may be polluted by lead (in house dust), formaldehyde, fire-retardants, radon, even volatile chemicals from fragrances used in conventional cleaners. Some pollutants are tracked into the home. Some arrive via a new mattress or furniture, carpet cleaners, or a coat of paint on the walls.

Keep Your Floors Fresh.
Suck it up. Chemicals and allergens can accumulate in household dust for decades. By using a vacuum with a HEPA filter, you can reduce concentrations of lead in your home. You can also get rid of other toxins, like brominated fire-retardant chemicals (PBDEs), as well as allergens like pollen, pet dander, and dust mites. Using a vacuum cleaner that has strong suction, rotating brushes, and a HEPA filter ensures that dust and dirt won't get blown back out in the exhaust. Don't forget walls, carpet edges, and upholstered furniture where dust accumulates. For best results, vacuum two or more times each week and wash out your filter regularly.
Mop it up. Mopping picks up the dust that vacuuming leaves behind. You can skip the soaps and cleaners and just use plain water to capture any lingering dust or allergens. New microfiber mops (and dust cloths) reportedly capture more dust and dirt than traditional fibers and don't require any cleaning solutions whatsoever.
Keep it out. Put a large floor mat at every door. People track in all sorts of chemicals via the dirt on their shoes. A doormat reduces the amount of dirt, pesticides, and other pollutants from getting into your home. If the mat is big enough, even those who don't wipe their shoes will leave most pollutants on the mat -- not the floors in your home.

Keep a Healthy Level of Humidity. Dust mites and mold love moisture. Keeping humidity around 30%-50% helps keep them and other allergens under control. A dehumidifier (and air conditioner during summer months) helps reduce moisture in indoor air and effectively controls allergens, Lang says. An air conditioner also reduces indoor pollen count -- another plus for allergy-sufferers.
- Use an exhaust fan or crack open a window when cooking, running the dishwasher, or bathing.
- Don't overwater houseplants.
- Vent the clothes dryer to the outside.
- Fix leaky plumbing to prevent moisture-loving mold.
- Empty drip pans in your window air conditioner and dehumidifier.

4. Smell Good Naturally. You may associate that lemony or piney scent with a clean kitchen or clean clothes. But synthetic fragrances in laundry products and air fresheners emit dozens of different chemicals into the air. You won't find their names on the product labels. Conventional laundry detergents, fabric softeners, dryer sheets, and air fresheners in solid, spray, and oil form may all emit such gasses.