A new study reveals that people may be exposed to unhealthy levels of airborne pollutants inside their homes, even if the outdoor air quality is good. Researchers at the University of Birmingham used low-cost sensors and innovative techniques over a two-week period to compare particulate matter (PM) in three homes.

Bringing aromas indoors with the help of chemical products -- yes, air fresheners, wax melts, floor cleaners, deodorants and others -- rapidly fills the air with nanoscale particles that are small enough to get deep into your lungs,