Which analytical techniques are used to detect lead in environmental samples among the options?

Which analytical techniques are used to detect lead in environmental samples among the options?

• A. Flame atomic absorption and graphite furnace atomic absorption
• B. Gas chromatography
• C. Mass spectrometry
• D. Infrared spectroscopy

Answer: (A)

Lead is a metal, so the measurements rely on techniques that quantify metal atoms in a sample. Flame atomic absorption spectroscopy and graphite furnace atomic absorption spectroscopy do exactly this: they atomize the sample and measure how much light lead atoms absorb at a characteristic wavelength. Flame AAS is good for moderate concentrations, while graphite furnace AAS provides higher sensitivity and lower detection limits for trace lead in environmental samples such as water, soil, dust, and air particulates. Gas chromatography is designed to separate volatile organic compounds and requires detectors suited to molecules, not elemental metals, so it isn’t used to quantify lead directly. Mass spectrometry can detect metals as well, especially when coupled with techniques like ICP, but the option listed as mass spectrometry alone isn’t the standard standalone method for lead detection in this context. Infrared spectroscopy measures molecular vibrations and is not suitable for detecting elemental lead. Therefore, the methods actually used to detect lead in environmental samples among the options are the flame and graphite furnace atomic absorption techniques.

Lead is a metal, so the measurements rely on techniques that quantify metal atoms in a sample. Flame atomic absorption spectroscopy and graphite furnace atomic absorption spectroscopy do exactly this: they atomize the sample and measure how much light lead atoms absorb at a characteristic wavelength. Flame AAS is good for moderate concentrations, while graphite furnace AAS provides higher sensitivity and lower detection limits for trace lead in environmental samples such as water, soil, dust, and air particulates. Gas chromatography is designed to separate volatile organic compounds and requires detectors suited to molecules, not elemental metals, so it isn’t used to quantify lead directly. Mass spectrometry can detect metals as well, especially when coupled with techniques like ICP, but the option listed as mass spectrometry alone isn’t the standard standalone method for lead detection in this context. Infrared spectroscopy measures molecular vibrations and is not suitable for detecting elemental lead. Therefore, the methods actually used to detect lead in environmental samples among the options are the flame and graphite furnace atomic absorption techniques.