How does AAS detect the presence of lead?

Atomic Absorption Spectroscopy (AAS) detects the presence of lead by measuring the amount of light absorbed by lead atoms when they are vaporized and exposed to light. In this technique, a sample is atomized into a gaseous state, often using a flame or graphite furnace, and then a beam of light, which is specific to lead, is directed through the vapor. As the lead atoms absorb this light, the amount of light transmitted through the sample decreases. By measuring this decrease in intensity, the concentration of lead in the sample can be determined.

This method is highly sensitive and can detect very low levels of lead, making it suitable for environmental monitoring as well as testing in various materials. The other methods mentioned, such as direct visual inspection or chemical reactions, do not utilize this specific and precise measurement process, which is fundamental to AAS's ability to quantify lead accurately.