Many of the products we encounter daily—from deodorant to pesticides to paint—release molecules that drift through the air. Breathing in enough of the wrong ones can cause serious and potentially long-term health problems. However, it can be hard to estimate exposure because current devices are limited in what they can detect. Today, researchers report development of a new personal air-sampling system that can detect an unprecedented range of these compounds from a special badge or pen attached to someone's shirt or placed in a pocket.