Which measurement determines lead content in paint chips?

Which measurement determines lead content in paint chips?

• A. X-ray fluorescence
• B. Atomic Absorption Spectroscopy
• C. Mass spectrometry
• D. Colorimetry

Answer: (B)

Measuring how much lead is in paint chips comes down to turning the solid paint into a solution and then precisely quantifying the metal in that solution. Atomic Absorption Spectroscopy is designed for this kind of measurement. It works by passing light at a wavelength specific to lead through the sample in a flame or graphite furnace. Lead atoms in the solution absorb some of that light, and the amount of light absorbed is directly related to the lead concentration. The more lead present, the more light is absorbed. To use this method, the paint chips are first digested with acids to release the lead from the paint matrix into a liquid. The resulting solution is then analyzed, and the instrument is calibrated with standards so the absorbance can be translated into a concentration. This concentration is then used to determine the lead content of the original chip, typically reported as a mass of lead per mass of paint. Graphite furnace atomic absorption spectroscopy, in particular, offers very high sensitivity and is well-suited for detecting trace levels of lead in paint samples, though flame AAS can also be used depending on the expected concentration. While other methods like X-ray fluorescence can screen for lead in some contexts, AAS provides a quantitative, laboratory-based measurement after digestion, which is why it’s the best choice for determining lead content in paint chips.

Measuring how much lead is in paint chips comes down to turning the solid paint into a solution and then precisely quantifying the metal in that solution. Atomic Absorption Spectroscopy is designed for this kind of measurement. It works by passing light at a wavelength specific to lead through the sample in a flame or graphite furnace. Lead atoms in the solution absorb some of that light, and the amount of light absorbed is directly related to the lead concentration. The more lead present, the more light is absorbed.

To use this method, the paint chips are first digested with acids to release the lead from the paint matrix into a liquid. The resulting solution is then analyzed, and the instrument is calibrated with standards so the absorbance can be translated into a concentration. This concentration is then used to determine the lead content of the original chip, typically reported as a mass of lead per mass of paint.

Graphite furnace atomic absorption spectroscopy, in particular, offers very high sensitivity and is well-suited for detecting trace levels of lead in paint samples, though flame AAS can also be used depending on the expected concentration. While other methods like X-ray fluorescence can screen for lead in some contexts, AAS provides a quantitative, laboratory-based measurement after digestion, which is why it’s the best choice for determining lead content in paint chips.