Previous Year Question
Due to improper/indiscriminate disposal of old and used computers or their parts, which of the following are released into the environment as e-waste?
Beryllium
Cadmium
Chromium
Heptachlor
Mercury
Lead
Plutonium
Select the correct answer using the code given below:
1, 3, 4, 6 and 7
1, 2, 3, 5 and 6
2, 4, 5 and 7
All of these
Correct Answer: B
Detailed Solution
E-waste includes discarded computers, monitors, circuit boards, batteries, cables and other electronic equipment.
Unsafe dismantling, burning or open dumping of these devices can release toxic substances into the environment.
Beryllium is used in certain electronic connectors, motherboards and spring-like components.
Inhalation of beryllium-containing dust can damage the lungs; therefore, Item 1 is correct.
Cadmium may be found in nickel-cadmium batteries, semiconductors and certain electronic components.
Cadmium can damage the kidneys and bones; therefore, Item 2 is correct.
Chromium is used to protect metal surfaces from corrosion and in certain electronic components.
Hexavalent chromium, in particular, can be toxic and carcinogenic; therefore, Item 3 is correct.
Mercury may be present in switches, relays, certain displays and lighting-related devices.
Mercury is a toxic element that affects the nervous system; therefore, Item 5 is correct.
Lead is found in computer components such as solder, cables and the glass of cathode-ray tubes.
Lead can particularly affect the nervous system and development of children; therefore, Item 6 is correct.
Heptachlor is an organochlorine pesticide and is not a normal component of old computers.
Plutonium is a radioactive element and is not a component of ordinary computer equipment.
Therefore, the correct e-waste-related elements are beryllium, cadmium, chromium, mercury and lead.