Question map
Which one of the following can be used to confirm whether drinking water contains a gamma emitting isotope or not?
Explanation
Correct answer is scintillation counter. Gamma rays are emitted by radioactive nuclides [1]. Radioactive elements can enter water supplies and contaminate drinking water [2]. Scintillation-based detectors (including liquid scintillation and gamma counters using NaI(Tl) crystals) are specifically designed to detect and quantify ionizing emissions by converting gamma interactions into light pulses which are then counted, making them suitable for measuring gamma-emitting isotopes in water samples [3]. A microscope observes material structure and cannot detect invisible ionizing radiation; a lead plate is shielding to reduce exposure rather than a detector; a spectrophotometer measures optical absorbance, not radioactive emissions. Standard laboratory protocols use scintillation counting for water radioactivity assays [3].
Sources
- [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > Radioactivity: > p. 82
- [2] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > v. Radioactive wastesi > p. 79
- [3] https://ehs.psu.edu/sites/ehs/files/lsc_theory_of_operation_part_1.pdf
- [4] https://www.epa.gov/sites/default/files/2015-05/documents/402-b-04-001b-15-final.pdf