Polychlorinated biphenyls (PCBs) are major environmental pollutants. Which of the following detectors would be most sensitive for GC analysis of PCBs? (24-8) Group of answer choices flame photometric (FPD) electron capture (ECD) flame ionization (FID) thermal conductivity (TCD) nitrogen-phosphorus (NPD)

The detectors that would be most sensitive for GC analysis of PCBs are

- Electron Capture Detectors (ECD)

Explanation:

Polychlorinated biphenyls(PCBs) are oily chemicals that are manufactured(man-made) and used as lubricants in electrical equipments such as transformers. They are grouped as major environmental pollutants because they are characterised as being very stable, as they are resistant to extreme temperature and pressure. Therefore with time the build up in the environment and can cause harmful health effects.

In the environment, it can be found distributed virtually everywhere incl, air water or soil. The PCBs can be analysed in the environment through the use of gas chromatography( GC) with electron capture detector (ECD) as the most sensitive detector. The method was found to be more sensitive as the number of chlorine atoms attached to the biphenyl increases.

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